AudioCircle

Industry Circles => GR Research => Topic started by: Hobbsmeerkat on 21 Sep 2020, 11:23 pm

Title: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 21 Sep 2020, 11:23 pm
For those following along in the Covid updates thread, Parts Express announced replacement drivers Based on the Neo3/8/10 drivers.
Feel free to catch up here: https://www.audiocircle.com/index.php?topic=169075.40

I just got my driver in today and wanted to compare the new GRS (Great Replacement Speakers) "Neo3" clone side by side with my standard (Non-PDR) BG Neo3.

(https://www.audiocircle.com/image.php?id=214937&size=large)

The first noticable difference is the use of bolts/nuts over rivets.
The position of the face also appears to be more simetrical top to bottom, where the Neo3 has its face shifted about 2mm higher.
The grill holes are also slightly smaller and are again, better centered within the protruding face, but its an issue that may arise more noticeably with waveguides or mounting plates.
The buffer layer between the magnets & diaphragm appears to be thinner on GRS model when compared to the Neo3.

GRS3:
(https://www.audiocircle.com/image.php?id=214941&size=large)
Neo3:
(https://www.audiocircle.com/image.php?id=214942&size=large)

(https://www.audiocircle.com/image.php?id=214938&size=large)
(https://www.audiocircle.com/image.php?id=214939&size=large)

First QC issue I've noticed is that the diagram isnt cleanly attached to or hidden by the frame. There are also a few spots where it sticks out, namely around the terminals, and mounting holes but it's a fairly minor nit-pick.

In the next few days I'll be doing some testing to see how they both perform as both dipole and using with my deep-cup mod.

I know HAL is going to also be doing some testing since they got one also, so hopefully we can use this thread to discuss these drivers more going forward!  :thumb:
Title: Re: GRS-3 vs Neo 3
Post by: Zitoun on 21 Sep 2020, 11:35 pm
Great stuff, thanks for sharing
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 22 Sep 2020, 12:45 am
When I bought my GRS-3 I also got a handful of cheap clips, some low mass banana plugs to make the testing easier, and reduce the risk of damaging the diagram from direct soldering.

So here how I set up the wiring:
(https://www.audiocircle.com/image.php?id=214950&size=large)
Title: Re: GRS-3 vs Neo 3
Post by: Zitoun on 22 Sep 2020, 02:22 am
Do you plan to do the GRS Neo10?, I will be very very interested if that can play in the super 7 league !
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 22 Sep 2020, 02:35 am
Do you plan to do the GRS Neo10?, I will be very very interested if that can play in the super 7 league !

I'm still on the fence about it, cuz its pretty pricey at $130 and I'll need to make a baffle to hold it. Something similar to the Super Mini, but I wanna get thru testing the GRS-3 first.
Title: Re: GRS-3 vs Neo 3
Post by: Zitoun on 22 Sep 2020, 05:17 am
OK I'll follow your thread then, let' see if the Neo3 is good first.
Title: Re: GRS-3 vs Neo 3
Post by: scararabe on 22 Sep 2020, 10:42 am
I look forward to reading your conclusions about differences in listening and measures of these two models !
Title: Re: GRS-3 vs Neo 3
Post by: Creative cut designs on 22 Sep 2020, 09:39 pm
Are these for that new speaker design you drew up?
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 22 Sep 2020, 09:55 pm
Nah, mostly just to see how they stack up to the official Neo 3.
Tho I don't have a PDR model to do a direct comparison, since mine is the original 10-magnet model. I believe HAL says his Neo3 is a PDR, so hopefully he can get a more direct comparison. But i will be doing the yarn mod, to get mine as close as possible.

Plus they're a relatively cheap option right now at 1/4 the price for a new item. Tho their regular price is $99 at 3/4 the cost of a Neo3. Might as well have some fun with them & see how well they hold up.
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 22 Sep 2020, 09:59 pm
Will you be taking any near-field measurements with REW ?  If you do, please post the .MDAT files.

TIA
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 22 Sep 2020, 10:15 pm
I certainly can!  :thumb:
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 23 Sep 2020, 01:10 am
Small update:
I can verify that my GRS-3 works, & there is definitely a difference in tone between them, just based on just messing around with both drivers.
I'm kinda surprised how different they both sound in my test baffle and with/without my cup mod. I can't quite describe the differences yet but you can definitely tell that the Neo3 is more sensitive and more "hollow" or "shouty"? The GRS-3 being a PDR style has better off-angle tone. (Danny's yarn mod not yet installed)

With the deep cup used on both models, there's better & fuller mids, but both definitely lack any bass, as expected.

The GRS-3 also has a wider face & doesn't fit into the stock BG circular mounting plate.
Title: Re: GRS-3 vs Neo 3
Post by: Zitoun on 23 Sep 2020, 03:18 am
Do you think they have different qualities or is there a clear winner already ?
 :popcorn:
Title: Re: GRS-3 vs Neo 3
Post by: Jon L on 23 Sep 2020, 03:38 am

With the deep cup used on both models, there's better & fuller mids, but both definitely lack any bass, as expected.


That's promising to hear.  The world definitely could use a worthy replacement for those Neo planar drivers.
I am especially interested in the new GRS "Slim" 8 inch planar drivers which are much cheaper than the 10".  Long and narrow, seems perfect for an easy open-baffle array :thumb:


(https://live.staticflickr.com/65535/50374154867_9252486a18_b.jpg) (https://flic.kr/p/2jKoHev)GRSslim8 (https://flic.kr/p/2jKoHev) by drjlo2 (https://www.flickr.com/photos/60017347@N03/), on Flickr
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 23 Sep 2020, 04:16 am
My biggest issue, as Danny pointed out, with the "Slim-8" is that it lacks the fabric damper layer that sits between the diaphragm and the magnets. So it's likely going to have ringing issues.
You'll likely be better off with the standard GRS-8/Neo8 clone, even if its response curve isn't as good, and moving to the GRS-3 for 7K Hz & up.

That said, it might make for an interesting DIY portable bluetooth bsetup, with a small down-firing woofer for everything below 600hz...

Tho I'm still confused why the felt stuffing only exists on the back side and not the front on either 8" driver... (I checked and the Neo8 PDR has felt on both the front and back sides)
:scratch:
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 23 Sep 2020, 04:34 am
I am interested in the NEO8S.  Don't know if this version is the NEO8 or NEO8S clone, but it does appear to go lower than the slim version.

(https://i.ibb.co/NyBc8t0/GRS-NEO8.jpg)
Title: Re: GRS-3 vs Neo 3
Post by: Zitoun on 23 Sep 2020, 04:45 am
Let us know the result of the test,
I'd like to see what can be done with the NEO10 clone, if that can be promising to recreate a S7 with a new crossover, I am IN. 8)
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 23 Sep 2020, 02:26 pm
I am interested in the NEO8S.  Don't know if this version is the NEO8 or NEO8S clone, but it does appear to go lower than the slim version.

I'm not 100% sure, but it looks like a weird hybrid of the Neo8S & PDR models. Its has the full 30 drivers like the 8S, but has the felt strips stuffed in the outer row like the Neo8 PDR, tho only in the rear..
You could stuff some thick yarn in the outer, front rows & probably make for a better hybrid.

That said, I cant go broke buying & testing every driver tho to test if it's a viable option.. :P
But if y'all want to help out or send me one for testing that's something we can talk about going forward.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 23 Sep 2020, 06:36 pm
Okay! Testing done!

(Technically not done at 1W, but was done at 1M from baffle to mic)
I ran 4 sweeps in total: 2 as OB, 2 with the back cup mod.
Sweeps were done, on axis, 500-20,000 Hz using REW with 1/24 smoothing.

Here's the test baffle/waveguide, with a dynamat product on the back to reduce resonance of the plastic.

(https://www.audiocircle.com/image.php?id=215036&size=large)
(https://www.audiocircle.com/image.php?id=215037&size=large)

Deep cup results:
(https://www.audiocircle.com/image.php?id=215041&size=large)
Red: Stock Neo3     Orange: GRS-3

OB results:
(https://www.audiocircle.com/image.php?id=215042&size=large)
Green: Stock Neo3       Blue: GRS-3

I'm honestly impressed, they both measure well. And quiet consistently to one another, esp in their OB/dipole config!

Tho I would say that the Neo3 does fare better in the deep cup tests, but for OB the GRS-3 doesn't appear to be a bad option, and can easily get you down to 900HZ

In the sweep, there are other minor sweeps near the end, where I would say that the Neo3 does sound clearer imo, but the difference is pretty minor, and for the price is a pretty nice way to go.
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 23 Sep 2020, 07:13 pm
How do the waterfall decays compare ?  Does the GRS have more ringing ?
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 23 Sep 2020, 07:36 pm
I wish I could get the same waterfalls as clio does, but they all still look really good. I'm not 100% sure why there's the extension in the upper ranges... I'm guessing that's from the other sweeps within the test?

Scale: 20dB-80dB

Neo3 OB:
(https://www.audiocircle.com/image.php?id=215043&size=large)

GRS3 OB:
(https://www.audiocircle.com/image.php?id=215044&size=large)

Neo3 Deep Cup:
(https://www.audiocircle.com/image.php?id=215045&size=large)

GRS3 Deep Cup:
(https://www.audiocircle.com/image.php?id=215046&size=large)
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 23 Sep 2020, 11:19 pm
I've installed Danny's yarn mod into my Neo3, so I'll be testing that later tonight once one of my house mates is no longer asleep.
I'm genuinely curious how it will affect the results, since its mostly intended for better off-axis results.

I have most of Saturday off, which I'll use for more testing, likely near-field (~1 inch past the wave guide) & off axis, along with some different combinations of the taller plastic rods on both drivers.
I may also rerun todays current test results outdoors to help remove any in-room reflections.
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 23 Sep 2020, 11:33 pm
I've installed Danny's yarn mod into my Neo3, so I'll be testing that later tonight once one of my house mates is no longer asleep.
I'm genuinely curious how it will affect the results, since its mostly intended for better off-axis results.

I have most of Saturday off, which I'll use for more testing, likely near-field (~1 inch past the wave guide) & off axis, along with some different combinations of the taller plastic rods on both drivers.
I may also rerun todays current test results outdoors to help remove any in-room reflections.

Thanks for doing this.  I am curious what is causing the ringing on both above 10KHz. 

When you measured it OB, did you have the wave-guide on it or just remove the cup off the back ?  I would assume the latter.

Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 24 Sep 2020, 12:58 am
Thanks for doing this.  I am curious what is causing the ringing on both above 10KHz. 

When you measured it OB, did you have the wave-guide on it or just remove the cup off the back ?  I would assume the latter.

The ringing is due the settings I had the gated window open too long. Here's the adjusted graphs, that also have the smoothing set to 1/12 to make it easier to read.

Neo3 OB:
(https://www.audiocircle.com/image.php?id=215059&size=large)

GRS3 OB:
(https://www.audiocircle.com/image.php?id=215060&size=large)

NEO3 Cup:
(https://www.audiocircle.com/image.php?id=215061&size=large)

GRS3 Cup:
(https://www.audiocircle.com/image.php?id=215062&size=large)

And yes, the waveguide was used for all tests, with only the cup removed for the OB tests.
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 24 Sep 2020, 01:38 am
The ringing is due the settings I had the gated window open too long. Here's the adjusted graphs, that also have the smoothing set to 1/12 to make it easier to read.

Neo3 OB:
GRS3 OB:

NEO3 Cup:
GRS3 Cup:

And yes, the waveguide was used for all tests, with only the cup removed for the OB tests.

Thanks for the update.  Those look much better and the deltas are few.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 24 Sep 2020, 02:12 am
Here's a Google Drive link for the REW .mdat file for those that wan't to look thru the files & maybe find more information than im aware of.  :thumb:

https://drive.google.com/file/d/1rZebamqfdhMaPuRtqK4aTUkQ5tq4haUh/view?usp=drivesdk
Title: Re: GRS-3 vs Neo 3
Post by: scararabe on 24 Sep 2020, 06:57 am
I downloaded the file mdat, and the GRS3 distortion from 1.2 to 2 kHz appears 10 times higher that of NEO3 in OB use ...
If my analysis is correct it is a great disappointment.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 24 Sep 2020, 12:56 pm
Yeah that 1.2-2K peak seems to persist in all tests, tho to be honest I'm not really sure how to read the graph beyond "lower is better" ?
I wouldn't call it 10x, but it might explain why mids sounded different between each model.

Here's the graphs for Total Harmonic Distortion for anyone interested:

Neo3 Cup:
(https://www.audiocircle.com/image.php?id=215064&size=large)

GRS 3 Cup:
(https://www.audiocircle.com/image.php?id=215066&size=large)


Neo3 OB:
(https://www.audiocircle.com/image.php?id=215065&size=large)

GRS3 OB:
(https://www.audiocircle.com/image.php?id=215067&size=large)
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 24 Sep 2020, 03:01 pm
If you change the scale from dB to Percent, you can see the distortion at

1.8kHz ranges from [0.2% to almost 2%, @ 10X] and at
570Hz ranges from [0.13% to 4.3%, @ 30X].

Distortion appears highest for OB/without the deep cup for both the Neo3 and the GRS clone at the lowest frequencies.

The hump at 1.8kHz is the GRS clone with or without the cup.

(https://i.ibb.co/2sYKQ31/Distortion-in-Percent.jpg)
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 24 Sep 2020, 03:30 pm
Ahh okay,
I wonder what causes that distortion at those points? esp when the response actually looks pretty good for the GRS3 in the OB setup..
Title: Re: GRS-3 vs Neo 3
Post by: Danny Richie on 24 Sep 2020, 09:48 pm
It is hard to get any meaningful distortion measurements outside of an anichoic chamber. The room noise is too high and it is hard to create a great enough differential to see the real data.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 24 Sep 2020, 10:39 pm
It is hard to get any meaningful distortion measurements outside of an anichoic chamber. The room noise is too high and it is hard to create a great enough differential to see the real data.

A fair point, to be sure.

I ordered a proper mic stand and extension cord, so i can hopefully get some cleaner results on Saturday assuming it arrives early enough or it may have to wait till Wednesday since i do have work late on Saturday night  then all day Sunday. But I should at least be able to get comparable results with the modified neo3 in the next day.
Title: Re: GRS-3 vs Neo 3
Post by: Zitoun on 25 Sep 2020, 12:35 am
How about the sound, did you try to run some listening session to have some qualitative measures, regarding tonality, soundstage, resolution etc ?

Does it worth trying Neo 10 ?
Title: Re: GRS-3 vs Neo 3
Post by: Danny Richie on 25 Sep 2020, 12:45 am
A fair point, to be sure.

I ordered a proper mic stand and extension cord, so i can hopefully get some cleaner results on Saturday assuming it arrives early enough or it may have to wait till Wednesday since i do have work late on Saturday night  then all day Sunday. But I should at least be able to get comparable results with the modified neo3 in the next day.

Try pulling the trigger on a measurement with the driver not plugged in so that all you get is room noise and see what that looks like.   :D
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 25 Sep 2020, 01:09 am
How about the sound, did you try to run some listening session to have some qualitative measures, regarding tonality, soundstage, resolution etc ?

Does it worth trying Neo 10 ?

I don't have a setup that allows me to do any of that. Plus i don't want to risk damaging the driver by playing a full range signal into it. But I did listen to parts of a podcat thru both drivers. And both sound nice overall, and tbh the Neo3 sounds clearer, & in the upper range, if not a little shouty in the waveguide, but a little lacking in the mids? The GRS-3 has warmer mids, but a little less detail in the top end.

They both sound pretty similar with the back cup mod installed with solid mids and highs, any bass below 700hz droping off a cliff. They both sound pretty good in my opinion tho, but I also don't have a trained ear to pick out the flaws and properly describe them.

I'm still considering it. But the GRS3 measures pretty well overall, despite the issues with the THD, plus it's not a bad idea to dig a little deeper into the GRS-10 model, since it's the one most people are interested in.

Try pulling the trigger on a measurement with the driver not plugged in so that all you get is room noise and see what that looks like.   :D

Sure, I think i can do that.. esp since everyone else is still asleep..  :lol:
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 25 Sep 2020, 01:38 am
Okay here's the measurements for the room I tested in, same rough position, but without the driver.

Room SPL:
(https://www.audiocircle.com/image.php?id=215096&size=large)

Room THD:
(https://www.audiocircle.com/image.php?id=215097&size=large)
Title: Re: GRS-3 vs Neo 3
Post by: Danny Richie on 25 Sep 2020, 01:46 am
Your room must be a lot quieter than most. That's really good. But you are also cutting it at 500Hz. Below that is usually where a lot shows up.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 25 Sep 2020, 02:13 am
Maybe? But It might be just depend on what devices are running? But I was cutting if off at 500 to prevent risk of damage to the drivers.

Here's 3 tests:
(https://www.audiocircle.com/image.php?id=215100&size=xlarge)
Magenta: with AC unit running outside about 10 ft away
Red: With upstairs unit defrosting
Green: No AC running, the room is near silent.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 25 Sep 2020, 02:46 pm
I ordered the GRS-10, should be here by Wednesday next week. :thumb:
I'll need to design and 3D print a test baffle for it over the next few days.
Title: Re: GRS-3 vs Neo 3
Post by: Captainhemo on 25 Sep 2020, 06:17 pm
Rich is currently  doing  some  tests with the GRS Neo 3 and Neo 10 in one of our tested/proven  Super Mini / Monolith baffles.   There is a bit of  size difference in the Neo3's but it sounds like they   do drop in.  The   screw positions are different on 2 of the Neo 10   mounting  screws.

Sure he'll be posting  some results  at  some point

jay
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 25 Sep 2020, 06:54 pm
Rich is currently  doing  some  tests with the GRS Neo 3 and Neo 10 in one of our tested/proven  Super Mini / Monolith baffles.   There is a bit of  size difference in the Neo3's but it sounds like they   do drop in.  The   screw positions are different on 2 of the Neo 10   mounting  screws.

Sure he'll be posting  some results  at  some point

jay

Oh! That's good to know! Im definitely interested to see his results.

I definitely noticed the fitment issues with the GRS-3, esp since it doesn't quite fit I the BG circular plate, and the screw heads are also taller than the rivets on the BG models. Plus having the face better centered on the GRS model means it sits offset to one sid of the waveguide, or needs to be inserted upside down.
I still need to check how it fits within the NX-Studio baffle tho.

I may end up just returning the drivers after my testing, unless someone else decides they wants it. Or if i find an interesting use for them instead. :thumb:
Title: Re: GRS-3 vs Neo 3
Post by: HAL on 25 Sep 2020, 08:00 pm
Have to wait for a no rain day to take the baffles outside to measure with CLIO Pocket setup.

Here are the GRS-3" and GRS-10" planars mounted in Jay's open baffles for trials.  You can see the top two screws in the 10" planar are not installed as the mounting holes are in different places than the BG NEO10.  No big deal, just have to predrill new ones.  The gaskets can be used for either front of rear mounting which is nice.  The 10" one has extra precut holes for rear mounting.

(https://www.audiocircle.com/image.php?id=215124)

(https://www.audiocircle.com/image.php?id=215125)

Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 25 Sep 2020, 08:12 pm
Thanks for Sharing, HAL, I'm excited to see your results! :thumb:

They fit in the Super-Mini baffle quite nicely, even if two of the mounting holes are a little off. It's an easy fix at least!
Title: Re: GRS-3 vs Neo 3
Post by: Captainhemo on 25 Sep 2020, 09:17 pm
If you  guys are  frilling new holes inthe   recess for the GRS drivers,  use the existing holes as a depth gauge and mark your bit.... there is not a  ton of room there before you 'd pop through into the  waveguide onthe frontside.

If these prove to be worthwhile,   I can add the extra  2  scerew holes to future cuts of the  Super Mini,  Super 7, and Super  LS (Line Force) cabinets

jay

jay
Title: Re: GRS-3 vs Neo 3
Post by: HAL on 25 Sep 2020, 11:14 pm
Jay,
Will do. 

Rich
Title: Re: GRS-3 vs Neo 3
Post by: Zitoun on 26 Sep 2020, 08:02 am
Waiting for the GRS 10 result, very interesting.

Will a super7 configuration (4xGRS10 +1xGRS3) affect the results by the way?

Based on result, can the drop of the  baffle can be addressed by Danny's magic crossover ?

Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 26 Sep 2020, 06:54 pm
Okay, I installed Danny's yarn mod to my Neo3 and ran the tests again both in OB & Deep-Cup setups, using same test setup and positioning as last time. (Check the previous pages for GRS & stock Neo3 comparison)

Modded OB:
(https://www.audiocircle.com/image.php?id=215143&size=large)

Modded Cup:
(https://www.audiocircle.com/image.php?id=215144&size=large)

Modded OB:
(https://www.audiocircle.com/image.php?id=215145&size=large)

Modded Cup:
(https://www.audiocircle.com/image.php?id=215146&size=large)

Modded OB THD:
(https://www.audiocircle.com/image.php?id=215147&size=large)

Modded Cup THD:
(https://www.audiocircle.com/image.php?id=215148&size=large)

The yarn mod does a better job than I expected!

Here's a few comparison charts:

(https://www.audiocircle.com/image.php?id=215150&size=large)
Blue: Stock Neo3 OB
Teal: Mod Neo3 OB

(https://www.audiocircle.com/image.php?id=215154&size=large)
Green: Stock Neo3 +cup
Purple: Mod Neo3 + cup

(https://www.audiocircle.com/image.php?id=215151&size=large)
Yellow: GRS3 OB
Teal: Neo3 Mod OB

OB THD:
(https://www.audiocircle.com/image.php?id=215152&size=large)
Blue: Stock Neo3
Teal: Mod Neo3

Cup THD:
(https://www.audiocircle.com/image.php?id=215153&size=large)
Green: Stock Neo3
Purple: Mod Neo3
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 27 Sep 2020, 10:16 pm
The string mod appears to have knocked down the distortion peaks. 

Will you be doing the same yarn mod test to the GRS NEO3 clone ?

TIA
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 27 Sep 2020, 11:04 pm
The string mod appears to have knocked down the distortion peaks. 

Will you be doing the same yarn mod test to the GRS NEO3 clone ?

TIA

No, cuz it already has thick felt strips where the yarn goes..
The GRS-3 is a PDR clone, while Danny's mod only works with standard BG & GR Neo3 models.
I imagine removing the felt would likely destroy the dampening layer in the process, making distortion much worse.

But it is interesting how the felt drops distortion on the high end, but spikes it below 800Hz. And while the cup mod does help reduce those distortion peaks, compared to OB, its also below the range where most Neo3s will be playing, so kind of inconsequential.
Title: Re: GRS-3 vs Neo 3
Post by: Captainhemo on 29 Sep 2020, 06:20 pm
I bet the  mod  helped the   horizontal off-axis  response as well.

For a refresh... here is the   GR Neo3 with  wool/yarn and  BG Neo 10  in   one of our Super Mini/Monolith  cabinets with  Danny's  2nd order   network
(http://gr-research.com/pics/Second%20order%20crossover%20response.jpg)
Will be interesting to see what  you  get  with the  GRS drivers  Rich


jay
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 29 Sep 2020, 07:47 pm
I'll be getting my GRS-10" this afternoon, but I still need to create a baffle for testing it. May just keep it simple with cardboard, but I may also get some mdf & a jigsawand to learn to use my tools a little better on something less important.
Title: Re: GRS-3 vs Neo 3
Post by: HAL on 29 Sep 2020, 07:54 pm
With the way the weather is going, probably will be later this week before making measurements with CLIO Pocket.

At least the latest 2.11 version is now installed and calibrated for use.

Title: Re: GRS-3 vs Neo 3
Post by: studiotech on 29 Sep 2020, 08:10 pm
GRS drivers arrived today.  Getting a set of Radian as well.  Will do full comparison of original BG, RADIAN and GRS and start new thread once complete. 

Greg
(https://www.audiocircle.com/image.php?id=215299)
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 29 Sep 2020, 08:25 pm
With the way the weather is going, probably will be later this week before making measurements with CLIO Pocket.

At least the latest 2.11 version is now installed and calibrated for use.

Wish I could afford a Clio Pocket, but its a little outta my price range, but I have purchased a cable and mic stand for my future tests, so at least its a step in the right direction. :P
(Using a Dayton Audio iMM-6 calibrate mic, intended for phones/tablets but it works pretty well)

But yeah, weather here likely isn't gunna be usable til Thursday at the soonest, but that Will give me tomorrow to figure out how I want to make the test baffle.

GRS drivers arrived today.  Getting a set of Radian as well.  Will do full comparison of original BG, RADIAN and GRS and start new thread once complete. 

Greg
(https://www.audiocircle.com/image.php?id=215299)

Nice! I'm definitely interested to see your results, esp for the GRS-8 & GRS-Slim8. :thumb:
Tho I'm disappointed to see the slim model still doesn't have the dampening layer like the other models. But I do wonder if using the yarn mod In the front will help since felt strips already exist in the back??
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 29 Sep 2020, 11:13 pm
Got my GRS-10" driver!
I'm surprised how hefty this is, it's really solidly built.

I do want to say tho, that there is actually the full 56 magnets (28 per side) within the driver, not the 42 listed in the Parts Express page.

Heres some pics I took:
(https://www.audiocircle.com/image.php?id=215301&size=large)

(https://www.audiocircle.com/image.php?id=215302&size=large)

(https://www.audiocircle.com/image.php?id=215303&size=xlarge)

You can see in the 2nd pic that there's a strip of rubber that hanging off, and that seems to be their attempt at covering the edges of the diaphragm that came loose, but considering how well built this is, as a whole, the edges are a nitpick on both of these models.

I'm definitely interested in seeing how it measures tho, cuz thats where it matters, I do wish I had a Neo-10 for a proper side-by-side comparison, but I'm definitely interested in what Danny has in the works with his own model.
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 30 Sep 2020, 12:57 am
GRS drivers arrived today.  Getting a set of Radian as well.  Will do full comparison of original BG, RADIAN and GRS and start new thread once complete. 

Greg
(https://www.audiocircle.com/image.php?id=215299)

Very cool.  Glad to see someone testing the NEO8 clones against the original BGs. 

UPS just delayed mine another day so they should be here on Thursday.
Title: Re: GRS-3 vs Neo 3
Post by: studiotech on 30 Sep 2020, 02:15 am
Just a word of caution for everyone testing these out.  DO NOT solder to the tabs.  It's very easy to overheat and damage the diaphragm.  Use crimp on terminals on the end of your wires.

Greg
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Sep 2020, 02:22 am
I'm using these for that reason, I do wish they were copper, but copper is also quite soft.
But for testing it makes the process a whole heck of a lot easier without the risk.

(https://www.audiocircle.com/image.php?id=215305&size=large)

Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Sep 2020, 04:44 am
I know it's late, but I connected my GRS 10  to my Sprout 100 just to listen, and, man its effeceint. Definitely lack much bass, but the 1000-10K range sound really fast & clean.. but there's definitely a focus on the upper part of that register with female vocals and cymbals.

(https://www.audiocircle.com/image.php?id=215308&size=large)

I really want to make a baffle for this asap to do some real resting..
Tho i kinda like HALs option of building a pair of Super Mini's with them, tho I'd have to sell them once they're assembled.
Title: Re: GRS-3 vs Neo 3
Post by: tate roth on 30 Sep 2020, 02:33 pm
These look really interesting, thanks for putting forward the effort to see if these GRS drivers are worth working with!  This is an AWESOME group.
Title: Re: GRS-3 vs Neo 3
Post by: Captainhemo on 30 Sep 2020, 02:52 pm
GRS drivers arrived today.  Getting a set of Radian as well.  Will do full comparison of original BG, RADIAN and GRS and start new thread once complete. 

Greg
(https://www.audiocircle.com/image.php?id=215299)

Greg , 
Which Radian's do you have  coming  ?

jay
Title: Re: GRS-3 vs Neo 3
Post by: studiotech on 30 Sep 2020, 03:01 pm
Jay, I'm ordering the LM8K.  Might as well test an variations of the 8.  I'm not personally interested in the smaller models as I'll continue to use Raal for top end.   
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Sep 2020, 05:18 pm
Some bad news..  :duh:

It was a nice cool overcast day, so I did my testing outside, but noticed the tests weren't as clean as thry should be & slowly getting worse, when I looked at my GRS driver, I think the heat from the sun softened the diagram or the foil adhesive too much, shifting the traces away from the center...
It's leading to a lot of heavy distortion. Along with a loss in the upper mid range from 4K-10K.

Before:
(https://www.audiocircle.com/image.php?id=214941&size=large)

After:
(https://www.audiocircle.com/image.php?id=215313&size=large)

So if you plan to do testing outside, keep it in the shade!  :nono:
Even my Neo3 shows signs of the same problem, tho because it had far less testing its not nearly as bad of shape..

On the better hand, I did get some interesting results from using the plastic rods. Having 3 tall rods (as seen in 2nd pic) causes a MASSIVE hole in the response around 8K hz, it's caused by the outer two rods. However, the inner rod actually allows for a small 3-5db rise in the 18-20K Hz range, without the drop at 8K.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Sep 2020, 05:34 pm
Hoo boy it's MUCH WORSE than I thought...

I opended up the GRS-3 to find this:
(https://www.audiocircle.com/image.php?id=215317&size=xlarge)

The diaphragm is absolutely SHREDDED. :o
I'm guessing the heat & higher output absolutely destroyed the driver... Bummer.

I'm guessing the Neo3 is going to look the same, but to a lesser extent.. *sigh* lol
Title: Re: GRS-3 vs Neo 3
Post by: AKLegal on 30 Sep 2020, 05:59 pm
Yikes!  How long were they in the sun? 
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Sep 2020, 06:04 pm
I'd say roughly hour & 15 minutes or so judging by the time stamps of the tests I ran.
Title: Re: GRS-3 vs Neo 3
Post by: Danny Richie on 30 Sep 2020, 06:43 pm
I'd say roughly hour & 15 minutes or so judging by the time stamps of the tests I ran.

And that is why we use Kapton film on ours instead of Kaladax.
Title: Re: GRS-3 vs Neo 3
Post by: HAL on 30 Sep 2020, 07:11 pm
It looks more like power got them as there looks like 3 burn places in the voice coil metalization, if I see the picture correctly.

Here are the GRS 3" and 10" planars in the Super Mini Baffles with CLIO Pocket using the latest 2.11 version software and the Log Sweep test.  The measurements are each on the center axis point of the drivers. 

Had limited measurements outdoors due to wind, power tools and traffic around the area.  Not able to do the original GR and BG drivers in the other baffle.

I am keeping the drive power to the planars down in level to not do the same as I had that happen to a BG NEO3-PDR once. 

(https://www.audiocircle.com/image.php?id=215325)
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Sep 2020, 08:26 pm
I'd imagine it was probably a fair bit of both, but if i need another standard Neo 3 it'll be one of Danny's.

In the meantime, I've already ordered another GRS-3 that should arrive Saturday, so i can do more testing with the rods since ive found that there are some visible results worth checking out.
But I'll keep the testing limited to indoors and around 60dB like my previous tests, but it was nice to see the cleaner waterfall and graphs from testing in an open space while they lasted.. :P
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 30 Sep 2020, 10:20 pm
I'd imagine it was probably a fair bit of both, but if i need another standard Neo 3 it'll be one of Danny's. ...

Couple of thoughts.

Could the rods be acting as insulators, preventing heat dissipation/cooling ???

If you used glue, could it have acted as a solvent weakening membrane ???



Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Sep 2020, 10:27 pm
I finally got a chance to do a little more digging thru the results and you can see in the distortion graph where the diaphram failed..

(https://www.audiocircle.com/image.php?id=215332&size=large)
Yellow: Good     Green: Failed

That said, heres how it reacts with the faceplate rods:
(https://www.audiocircle.com/image.php?id=215333&size=large)
Teal: Stock
Magenta: Outer rods only
Purple: Center rod only

Reminder: The tweeter was long ruined at this point, so once the replacement arrives, ill be re-testing the different rods to see if the differences percist/change.

Couple of thoughts.

Could the rods be acting as insulators, preventing heat dissipation/cooling ???

If you used glue, could it have acted as a solvent weakening membrane ???

They failed before I ever put the rods on. I actually only noticed the issue once I put the rods on. Even on a cloudy day with a light breeze, it was too much heat for the kaladex to handle under the stress of the movement.

I didnt use glue, I used thermal transfer tape intended for small heatsinks on small electronics.
Title: GRS PT6825-8 8" Planar Mid/Tweeter 8 Ohm
Post by: emailtim on 3 Oct 2020, 07:01 pm
If this should be moved to another thread, please let me know.

I received two of the GRS NEO8 "wide" drivers and have placed them in two 20" tall x 8" wide x 3/4" thick MDF baffle with a 16" side wing (Danny, I watched your latest video =).  Drivers are mounted in the back with the rectangular hole and the vertical edges of the baffle rounded with a quarter-round bit.

I specifically asked Parts-Express why the website description stated low distortion above 500Hz while the frequency chart showed the NEO8's going lower than 500Hz.  They avoided the question in their response.

"...  With the ability to provide low distortion output from 500-20,000 Hz ..."

The following plot is an in-room THD response of both drivers.  You can see they have rising distortion under 500Hz ([1.5% - 2%] up from 0.5%), thus the blurb on their website appears to be accurate.

(https://i.ibb.co/wJbQqPn/GRS-NEO8-wide-Distortion.jpg)
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 3 Oct 2020, 07:59 pm
I would say I'm surprised by the differences in THD, but the distortion is still lower in percentage than that between my now dead Neo 3 & GRS-3. Esp in the 1.2K-2K range. However, if that same distortion hump doesnt appear on my 2nd driver it might all be down to simple manufacturing tolerances...  :scratch:

But it is interesting that both GRS-3 & GRS-8 show increasing distrortion below full extent of their bottom end.. I'm guessing it has to do with the distance the diaphram is able to travel before hitting the damper layers/magnets?
I'm curious how the GRS-10 acts in that regard. I imagine it'll play down lower but will start hitting distortion issues around 300Hz?

I'm also really curious about the jagged pattern above 2.5K...
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 3 Oct 2020, 09:16 pm
"... I'm also really curious about the jagged pattern above 2.5K...   

The jagged pattern on the right is a product of using the option "Use Harmonic Freq as Reference" option.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 3 Oct 2020, 09:35 pm
"... I'm also really curious about the jagged pattern above 2.5K...   

The jagged pattern on the right is a product of using the option "Use Harmonic Freq as Reference" option.

Gotcha
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 4 Oct 2020, 02:25 pm
Finally got a chance to test my new GRS-3 with 3 different rod sizes.
Small round-overs, Medium and tall "waveguides"

(https://www.audiocircle.com/image.php?id=215444&size=large)

Rather than post 1000 charts again I'll just be sharing the MDAT file for y'all to look thru. Each measurement is labeled in the notes section, with the last measurement being stock measurement.

MDAT:
https://drive.google.com/file/d/1EHCbDWIFV7KVVfvPiBZ49gwto_B2_DBd/view?usp=drivesdk

SPL
(https://www.audiocircle.com/image.php?id=215445&size=large)

THD
(https://www.audiocircle.com/image.php?id=215446&size=large)

It maybe the due to the differences in testing, but the SPL graph isnt as good as the previous sample, and measures more similarly to the damaged model? That said, the THD graphs are a lot more consistent, esp above 1K Hz.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 9 Oct 2020, 07:40 pm
Been busy lately and its only gunna get busier next week since my job is currently understaffed thanks to people in quarantine or Vacation, so I'll probably be out of pocket for the next several days.

That said, I designed & am currently printing a "super-mini" clone front baffle for testing the GRS-10 (not able to include a mount for the GRS-3/Neo3 tho. Should be finished early tomorrow morning and ready for gluing/assembly, and I'll do my testing once the opportunity arrises, but i can't make any promises it'll be any time in the immediate future. Esp since I've also got my housemates schedules to contend with, on top of working everyday until Thursday when I leave for Dallas, TX.
Title: Re: GRS-3 vs Neo 3
Post by: Broncosaurs on 9 Oct 2020, 08:49 pm
Don't take too long, we are waiting... :popcorn:
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 10 Oct 2020, 02:52 pm
Print finished just as soon as i got home for my lunch break!
Its not perfect, but here's the rough test fit before i permanently epoxy the two halves together! :thumb:

(https://www.audiocircle.com/image.php?id=215655&size=large)

(https://www.audiocircle.com/image.php?id=215656&size=large)

Bonus is i can use tape/cardboard to create a faux side wing to match the original design. :D

Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 11 Oct 2020, 11:57 am
Here are some quick & dirty graphs i made this morning:

SPL:
(https://www.audiocircle.com/image.php?id=215675&size=large)

THD:
(https://www.audiocircle.com/image.php?id=215689&size=large)


Waterfall:
(https://www.audiocircle.com/image.php?id=215690&size=large)

Ill post better ones after i get off work, cuz i know the waterfall & THD only show to ~500Hz

Okay! Graphs are updated! The distortion below 400Hz doesnt look good, but it also seems to be related to the fall or rise in SPL. Namely the dips at 300&400Hz and then down to 100Hz.
The next chance I get to run some tests, I want to attempt with addition of a side wing to see if it helps smooth out the response and helps extend the bass & reduce the distortion in those regions as well.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 11 Oct 2020, 11:37 pm
Some more random testing since i had a little time before dinner:
Wing is 11" & near field test is 3" from center of driver.

SPL:
(https://www.audiocircle.com/image.php?id=215696&size=large)
Green: Near+wing    Yellow: 1M no wing     Magenta: 1M with 11" wing

THD:
(https://www.audiocircle.com/image.php?id=215697&size=large)
Green: Near+Wing    Yellow: 1M
Title: Re: GRS-3 vs Neo 3
Post by: HAL on 16 Oct 2020, 12:07 am
Well after 3 days of trying to measure outside with CLIO Pocket version 2.11, here is the best frequency response of the GRS 10" Planar I was able to measure.   The planar is mounted in the stock Super Mini Baffle with the measurement mic at 50" from the center of the planar. 

The baffle would need mods to mount the GRS planar for a better fit.  The GRS 10" planar is slightly larger than the BG NEO10.

The time gate used was ~6mS and no reflections were in that time.   The external noise and wind were a big problem with the pressure mic for the log sweep measurement, even though the time window is wide for a quasi-anechoic style measurement.

(https://www.audiocircle.com/image.php?id=215846)


Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 16 Oct 2020, 12:33 am
Well after 3 days of trying to measure outside with CLIO Pocket version 2.11, here is the best frequency response of the GRS 10" Planar I was able to measure.   The planar is mounted in the stock Super Mini Baffle with the measurement mic at 50" from the center of the planar. 

The baffle would need mods to mount the GRS planar for a better fit.  The GRS 10" planar is slightly larger than the BG NEO10.

The time gate used was ~6mS and no reflections were in that time.   The external noise and wind were a big problem with the pressure mic for the log sweep measurement, even though the time window is wide for a quasi-anechoic style measurement.

(https://www.audiocircle.com/image.php?id=215846)


I managed to do some outside tests, but im currently in Dallas, TX, away from my laptop, but your results are pretty similar to mine tho i think I saw a steeper rolloff on the bottom end since i dont have a proper winged baffle to work with.

The only way to get a curve like the product pdf is bt having the mic ~4" from the driver rather than 1M
Title: Re: GRS-3 vs Neo 3
Post by: HAL on 16 Oct 2020, 12:42 am
Yes, but that does not tell you the effect of the baffle on the drivers frequency response in a room   Why you need to also do far field (quasi-anechoic) style measurements. 
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 16 Oct 2020, 01:32 am
Yes, but that does not tell you the effect of the baffle on the drivers frequency response is a room   Why you need to also do far field (quasi-anechoic) style measurements. 

For sure, I mostly only did the near field test as a last pass, (both indoors & out) I definitely need go construct a proper wing for my test baffle as well probably just using cheap plywood.

And I probably might also make some adjustments to my model and print a new baffle that better fits the GRS-10. Both the face & mounting areas for a cleaner fitment overall. I didnt leave enough tolerance in my design, so its fitment a little sloppy.

But its a fun learning process nonetheless! :thumb:
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 16 Oct 2020, 01:42 am
...

And I probably might also make some adjustments to my model and print a new baffle that better fits the GRS-10.

...

FWIW, how long does it take to 3D print one of your typical baffles ?  I have never used a 3D printer before.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 16 Oct 2020, 01:50 am
FWIW, how long does it take to 3D print one of your typical baffles ?  I have never used a 3D printer before.

The baffle I printed for the GRS-3 took about 22 hrs, and the wave guide took another 8-10hrs i believe.

The two halves for the GRS-10 took about 18 hours total but it also has a low infill rate g was printed a bit faster & thicker layer height than the standard. had I gone for standard quality, it would have taken about 28-30 hours.
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 17 Oct 2020, 03:44 am
The baffle I printed for the GRS-3 took about 22 hrs, and the wave guide took another 8-10hrs i believe.

The two halves for the GRS-10 took about 18 hours total but it also has a low infill rate g was printed a bit faster & thicker layer height than the standard. had I gone for standard quality, it would have taken about 28-30 hours.

Thanks for the info.  It takes a while.
Title: Re: GRS-3 vs Neo 3
Post by: emailtim on 17 Oct 2020, 03:54 am
FWIW, here is an in-room response of the GRS NEO8 "wide" flush mounted and center offset on a 12" flat baffle with a high pass XO.  The plots are with (blue) and without (green) High/Low Shelves.

With the wing version, I get 2 bumps in the middle and 1 on each end.

With the flat baffle, 1 of the bumps in the middle goes away on its own and loses some low end.

With 4 High/Low Shelves (no PEQs), I get +/- 1dB (blue) on the flat baffle.

THD looks better on the GRS NEO10 plots posted above than what I see with the NEO8.

(https://i.ibb.co/nkk5jXB/Flat-Baffle-with-and-without-High-Low-Shelves.jpg)
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Oct 2020, 02:15 am
Printed an update to the waveguide to better fit the drivers' faceplate to the back of the waveguide, & change its shape a little. Also took some time to sand the corners/edges.
Hopefully I can get some time to test it soon for direct comparisons to the previous waveguide. :thumb:
(Maybe my NX studio waveguide as well)

(https://www.audiocircle.com/image.php?id=216360&size=large)
Title: Re: GRS-3 vs Neo 3
Post by: studiotech on 30 Oct 2020, 05:21 am
My measurement results now posted over at diy audio exotic and planar forum. 

https://www.diyaudio.com/forums/planars-and-exotics/360339-planar-drivers-express-10.html
Greg
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Oct 2020, 03:03 pm
My measurement results now posted over at diy audio exotic and planar forum. 

https://www.diyaudio.com/forums/planars-and-exotics/360339-planar-drivers-express-10.html
Greg

That thread is a pretty good read! Thanks for sharing!

And I see someone shared my blunder of killing my original GRS3 outdoors to boot  :lol:
I'm just happy I didn't kill my GRS 10 while testing outside, tho i think waiting until the sun went down was to my benefit, cuz anything matte-black is going to absorb a lot of heat, even on a cloudy day. :P
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 30 Oct 2020, 06:43 pm
Lucky me, I managed to get the house to myself for my lunch break, so I ran som quick tests with 3 different waveguides.

(https://www.audiocircle.com/image.php?id=216369&size=xlarge)
Purple: New guide    Orange: Old guide    Blue: NX guide

I think the biggest issue will the Studio waveguide is that there is a ~3mm gap from the faceplate to the start of the waveguide. My Neo3 is closer to a 1mm gap. There would need to be some design changes in order to fit the GRS model. Shouldn't be an issue for Dannys model that is closer to the design of the BG models.

Otherwise both new and old wave guides are pretty similar with a moderately more even response, except for the steeper dip at 9-10K Hz

Despite how well they all appear to play down to 600Hz there's a ton of distortion below 800-900Hz. Overall, tho the distortion was rather consistent across the board, never passing 2% except for the old waveguide that showed a peak around 8-9K around 2.5%. with the others being closer to1.5% in the same range. (Didnt have time to grab a good screenshot)

I still need to make a faceplate similar to the BG model used in the old N1, N2 & N3 and similar models that fits all Neo3s as the tolerances for ghe BG model are far too tight to fit the GRS-30, much like the NX waveguide, leaving a ~3mm gap between the faceplate and driver..
Title: Re: GRS-3 vs Neo 3
Post by: DA on 31 Oct 2020, 01:23 am
What's the point of the waveguides in the Neo10/3 combination? I know the waveguide increases output level and controls directivity.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 31 Oct 2020, 02:00 am
What's the point of the waveguides in the Neo10/3 combination? I know the waveguide increases output level and controls directivity.

Waveguides also increase the lowest playable octaves of the tweeter, allowing them to blend more smoothly, and transition to a faster, lighter driver sooner than if it was flush mounted.
Title: Re: GRS-3 vs Neo 3
Post by: DA on 31 Oct 2020, 02:10 am
Yep, forgot the 3rd benefit. Thanks
But not sure what the lower crossover does for the Neo10. Matching directivity of the mid and tweeter and gaining efficiency I get.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 31 Oct 2020, 03:46 am
Here's the THD graph for the 3 waveguides.

(https://www.audiocircle.com/image.php?id=216394&size=xlarge)
Purple: New     Orange: Old      Blue: NX-Studio
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 31 Oct 2020, 01:09 pm
A fun little tidbit for today:
Watching Paul McGowans latest video, & it looks like PS Audio is developing their own Neo-3 & Neo-10 clones now too. The neo 3 has a shallow back cup with the PS Audio logo.

(https://www.audiocircle.com/image.php?id=216401&size=large)
Title: Re: GRS-3 vs Neo 3
Post by: DA on 31 Oct 2020, 05:00 pm
Wonder if they're all made in the same factory?  :wink:
Title: Re: GRS-3 vs Neo 3
Post by: Early B. on 31 Oct 2020, 05:56 pm
A fun little tidbit for today:
Watching Paul McGowans latest video, & it looks like PS Audio is developing their own Neo-3 & Neo-10 clones now too. The neo 3 has a shallow back cup with the PS Audio logo.

Interesting. It seems that the price-to-sound ratio is so high that manufacturers and the DIY community will likely flock to design speakers with them. Imagine a $750 monitor with Neo3's & 10's.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 31 Oct 2020, 07:00 pm
Interesting. It seems that the price-to-sound ratio is so high that manufacturers and the DIY community will likely flock to design speakers with them. Imagine a $750 monitor with Neo3's & 10's.

It's definitely a well designed tweeter & performs quite well and can reach down pretty low often in the 1k range, esp with a wave guide.

That said, a neo3+10 setup does exist, tho due to availability issues of the Neo10, it's definitely expensive.. and even with the GRS10, wich is 1/3 the cost but doesn't seem to play all that low. Even with a winged baffle.. it measures down to 150-200Hz in near field, but loses its impact below 400-500hz. So it would work great for a 3-way but not too well on its own in an OB setting.
Title: Re: GRS-3 vs Neo 3
Post by: Early B. on 31 Oct 2020, 08:08 pm
It's definitely a well designed tweeter & performs quite well and can reach down pretty low often in the 1k range, esp with a wave guide.

That said, a neo3+10 setup does exist, tho due to availability issues of the Neo10, it's definitely expensive.. and even with the GRS10, wich is 1/3 the cost but doesn't seem to play all that low. Even with a winged baffle.. it measures down to 150-200Hz in near field, but loses its impact below 400-500hz. So it would work great for a 3-way but not too well on its own in an OB setting.

Oh, I see. I saw HAL earlier in this thread with a set of these as OB monitors and assumed it could be get down to 150-200 Hz cleanly and allow a pair of OB subs to take over from there. Thanks for clarifying.
Title: Re: GRS-3 vs Neo 3
Post by: DA on 31 Oct 2020, 08:44 pm
It's definitely a well designed tweeter & performs quite well and can reach down pretty low often in the 1k range, esp with a wave guide.

That said, a neo3+10 setup does exist, tho due to availability issues of the Neo10, it's definitely expensive.. and even with the GRS10, wich is 1/3 the cost but doesn't seem to play all that low. Even with a winged baffle.. it measures down to 150-200Hz in near field, but loses its impact below 400-500hz. So it would work great for a 3-way but not too well on its own in an OB setting.

I'm not sure where you are getting that the GRS 10" doesn't go as low as the Neo10. Studiotech has measurements over at diyaudio.com (I think he linked to it earlier in this thread) directly comparing them and the GRS looks very close in response.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 31 Oct 2020, 08:48 pm
I mean, it might be able too? But from my own results im not seeing anything that says it can get much lower than 300hz. But there may be details/info I'm missing in my measurements that would lead me to believe they can.

But even looking back at the official BG Neo 10 graph, it's sensitivity is pretty low in the 200-500Hz, and maybe thats what im missing? Esp if it's able to be used reliably with the Neo 3 in the past..
Title: Re: GRS-3 vs Neo 3
Post by: DA on 31 Oct 2020, 09:43 pm
I'm certainly no expert on the Neo10 but just based on the comparison measurements that Studiotech did, I think the GRS can play down to 200 Hz with about 90db efficiency without a wavequide just like the Neo10. It has a rising response starting around 500Hz just like the Neo10 but with a larger peak at around 9kHz to deal with. I believe he did measurements with no baffle so maybe that could impact each differently when loaded by one.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 31 Oct 2020, 10:45 pm
Managed to snag a deal on a pair of older, used Neo3 PDR tweeters for $75 on ebay. They're some kinda ugly "chrome" models, that used the older bodyframe before the more recent 6-rivet design.

(https://www.audiocircle.com/image.php?id=216424&size=large)

I'm curious to test them since they're different aesthetically, but more similar to the GRS-3 where it counts. Hopefully their age/condition won't be too much of a factor in their results, cuz i do know that older models are known for failing prematurely.
Title: Re: GRS-3 vs Neo 3
Post by: DA on 1 Nov 2020, 12:38 am
Nice score, considered those myself but have a pair waiting already to another design I'm contemplating.  :thumb:
Title: Re: GRS-3 vs Neo 3
Post by: HAL on 1 Nov 2020, 01:56 am
Just to clarify my measurement, the GRS 10" planar does go down to 200Hz at 9dB down in the Super Mini baffle.  It does not have the same response in the baffle as the BG NEO10.  That is why I stated the existing open baffles and XO would need to change from the stock drivers.  If you are doing it passively, then it would need to be 6dB down at 200Hz to crossover to the servo subs, which is what the BG NEO10 does.

If you use a dspMusik XO as I do, it can be EQ'd to work. 
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 1 Nov 2020, 02:15 am
Just to clarify my measurement, the GRS 10" planar does go down to 200Hz at 9dB down in the Super Mini baffle.  It does not have the same response in the baffle as the BG NEO10.  That is why I stated the existing open baffles and XO would need to change from the stock drivers.  If you are doing it passively, then it would need to be 6dB down at 200Hz to crossover to the servo subs, which is what the BG NEO10 does.

If you use a dspMusik XO as I do, it can be EQ'd to work.

Okay so I'm not entirely wrong then. Cuz I did some more testing the other day, with a bigger wing & some spare norez to better simulate a Super mini baffle, and I could still only get down to about 300-ish Hz fairly reliably. Near-field, it can easily hit 150-200Hz, but it falls off pretty hard beyond a foot or so.

Tho i am curious how the GRS10 will handle a sealed enclosure... And how it will change the overall response. But i do want to test it without a baffle/pseudo waveguide, as well a few other ideas ive had in my head lately.
Title: Re: GRS-3 vs Neo 3
Post by: HAL on 1 Nov 2020, 03:21 am
Then something is different, as my 50" on axis measurement shows results to 200Hz at -9dB, so not dropping like a rock.  It is 3dB lower than a BG NEO10, but not unusable at 200Hz as the Super Mini was designed.  An array of GRS 10" might get to 150Hz at -6dB down with this type of baffle.  Simple EQ can bring one GRS 10" response up to match at 200Hz.   

The 12" OB servo subs will work well up to 200Hz, and I use mine that way with my DSP XO version of the Super Mini's with the BG NEO10 and GR-NEO3.  The GRS 10" would need changes to work that way in this type of baffle.   

How it sounds is the question doing the changes.
Title: Re: GRS-3 vs Neo 3
Post by: DA on 1 Nov 2020, 01:52 pm
Just to clarify my measurement, the GRS 10" planar does go down to 200Hz at 9dB down in the Super Mini baffle.  It does not have the same response in the baffle as the BG NEO10.  That is why I stated the existing open baffles and XO would need to change from the stock drivers.  If you are doing it passively, then it would need to be 6dB down at 200Hz to crossover to the servo subs, which is what the BG NEO10 does.

If you use a dspMusik XO as I do, it can be EQ'd to work.

When you say 9db down, are you talking from about 100db where its efficiency is from around 1.5-6k before it stats to peak? So could it achieve 90db down to 200Hz if the rest if the response was tilted to match it?
Title: Re: GRS-3 vs Neo 3
Post by: HAL on 1 Nov 2020, 03:40 pm
I used the average around my 1.2KHz measurement for this driver and then look at LF rolloff in this baffle.  If the measurement shown for the GRS 10" in the specs is about 90dB at 1.2KHz at 1 meter, then it should be about 81dB@2.83v/1m at 200Hz in this baffle.

The hump in the response from specs at about 200Hz looks like a panel resonance from the response in the impedance plot also shown.  I do not see it farfield in the measurements of this baffle.   As Hobbsmeerkat has shown he sees it in nearfield measurements.  Since no baffle type is stated for the GRS measurement, it is hard to tell, but the data looks scaled from nearfield measurements.  You need to measure it in the baffle design to see what really happens.

Lifting the response with EQ 9dB near a resonance is not a good thing to do. 
Title: Re: GRS-3 vs Neo 3
Post by: DA on 1 Nov 2020, 04:12 pm
I used the average around my 1.2KHz measurement for this driver and then look at LF rolloff in this baffle.  If the measurement shown for the GRS 10" in the specs is about 90dB at 1.2KHz at 1 meter, then it should be about 81dB@2.83v/1m at 200Hz in this baffle.

The hump in the response from specs at about 200Hz looks like a panel resonance from the response in the impedance plot also shown.  I do not see it farfield in the measurements of this baffle.   As Hobbsmeerkat has shown he sees it in nearfield measurements.  Since no baffle type is stated for the GRS measurement, it is hard to tell, but the data looks scaled from nearfield measurements.  You need to measure it in the baffle design to see what really happens.

Lifting the response with EQ 9dB near a resonance is not a good thing to do.

No baffle was used for those measurements but it shows the Neo10 with the same measurement setup.
I wasn't talking about raising the lower frequency to match the upper, more the opposite. Bottom line is I'll have to do as you suggest and just buy a couple and measure in a baffle. Thanks

Don
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 5 Nov 2020, 04:57 pm
Got my Chrome Neo3 PDR tweeters yesterday!
They're actually kinda pretty once you wipe off the finger prints and smudges... lol

(https://www.audiocircle.com/image.php?id=216607&size=large)

(https://www.audiocircle.com/image.php?id=216608&size=large)

I also did some A-B testing with each chromed Neo 3 to see how they measure.

SPL:
(https://www.audiocircle.com/image.php?id=216609&size=large)

THD:
(https://www.audiocircle.com/image.php?id=216610&size=large)
Yeahh.. One of these are definitely blown out, it sounds horrendous... at least I got one working model thats somewhat similar to the GRS 3.. :P
it doesn't appear to be torn/shredded like my Neo 3 or original GRS3 tho, so possibly a tensioning issue with the disaphram?

SPL:
(https://www.audiocircle.com/image.php?id=216611&size=large)
THD:
(https://www.audiocircle.com/image.php?id=216612&size=large)
Purple: Neo3 PDR      Green: GRS3

The GRS3 is about 5dB more effecient (not shown here), has a better response top-end except for the dip around 10K, & the THD is cleaner below 1500Hz.
Title: Re: GRS-3 vs Neo 3
Post by: DA on 5 Nov 2020, 10:34 pm
Well that stinks. They are pretty cool looking though.

Don
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 7 Nov 2020, 06:59 pm
Well that stinks. They are pretty cool looking though.

Don

They're still pretty cool even if they're not usable, but i didnt expect too much out of them considering their age.

I worked on a design for a faceplate that mimics the stock BG faceplate. As well as a fun design that covers the outer two rows, narrowing the width of the waveguide to see if that can remove the 10dB drop around 10K Hz.

(https://www.audiocircle.com/image.php?id=216668&size=large)

I also printed out the faceplate, hopefully i can test it tomorrow, and print the narrow waveguide tonight.

(https://www.audiocircle.com/image.php?id=216669&size=large)

Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 6 May 2021, 12:58 am
Danny did some quick testing today with the GRS-10 clone in the Super Mini baffle.
He said it was a workable alternative, it just needs a notch filter to bring down a hump around 600-700Hz by a couple dB, but seems to measure better than in my own testing.

I believe some wanted to use them to make a LineForce since they're fairly priced & BG Neo10s haven't been available, especially lately, and they should work pretty well once the changes to the crossover are made.  :thumb:

I'll update once Danny has a chance to email the measurements.
Title: Re: GRS-3 vs Neo 3
Post by: DA on 6 May 2021, 12:11 pm
Thats great to hear. Would like to try out the Super Mini with the GRS drivers. Thanks
Title: Re: GRS-3 vs Neo 3
Post by: david45 on 6 May 2021, 03:38 pm
Danny did some quick testing today with the GRS-10 clone in the Super Mini baffle.
He said it was a workable alternative, it just needs a notch filter to bring down a hump around 600-700Hz by a couple dB, but seems to measure better than in my own testing.

I believe some wanted to use them to make a LineForce since they're fairly priced & BG Neo10s haven't been available, especially lately, and they should work pretty well once the changes to the crossover are made.  :thumb:

I'll update once Danny has a chance to email the measurements.

Thank you for posting this. Can’t wait to hear more from Danny   :)
Title: Re: GRS-3 vs Neo 3
Post by: SoCalWJS on 6 May 2021, 04:04 pm
Danny did some quick testing today with the GRS-10 clone in the Super Mini baffle.
He said it was a workable alternative, it just needs a notch filter to bring down a hump around 600-700Hz by a couple dB, but seems to measure better than in my own testing.

I believe some wanted to use them to make a LineForce since they're fairly priced & BG Neo10s haven't been available, especially lately, and they should work pretty well once the changes to the crossover are made.  :thumb:

I'll update once Danny has a chance to email the measurements.
Good News!

I hope they work out. Brings a whole bunch of speaker designs back as options.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 8 May 2021, 12:31 am
Got the graphs from Danny, as well as the Neo10 graphs.

So for reference, here's the original Neo10 on-axis response in the super mini frame:
(https://www.audiocircle.com/image.php?id=224312&size=large)

Here's the GRS 10:
(https://www.audiocircle.com/image.php?id=224313&size=large)

Despite its rising response peaking at 110dB, It seems to be a little more effecient and can play a little lower than the original BG10.

Here's the response of each with only an inductor in the circuit:

BG Neo10:
(https://www.audiocircle.com/image.php?id=224314)

GRS10:
(https://www.audiocircle.com/image.php?id=224315)

The hump at 700Hz needs to be brought down with a notch filter, vs the BG model that only has a 2nd order filter, but it definitely is a workable alternative!  :thumb:

Here's the original Super-mini response including the GR Neo3, both using a 2nd order filter.
(https://www.audiocircle.com/image.php?id=224316)

Here's the GRS10 using the same 2nd order filter, without a neo3/GRS3 to match it.
(https://www.audiocircle.com/image.php?id=224317)

Didn't get a chance to include a notch filter in the results, but its still good to hear it should actually be a pretty good alternative for those looking to build a SuperMini/ Lineforce, without hunting down the BG units!

Cheers! :thumb:
Title: Re: GRS-3 vs Neo 3
Post by: DA on 8 May 2021, 12:32 pm
Thanks for sharing this data. Good to know the GRS 10" can cover down lower than first thought with a little crossover work to get a flat response. Looking forward to trying it out.
Title: Re: GRS-3 vs Neo 3
Post by: david45 on 9 May 2021, 12:38 am
+1
Thank you for sharing this data  :D
Title: Re: GRS-3 vs Neo 3
Post by: wolp on 1 Jul 2021, 03:50 am
In the case that some people have actually bought and tried the GRS-3 or PT2522-4, can anyone confirm that they sound as good as they measure?
I'm thinking of using them in an OB design, but i'm happy to shell out for the GR Neo 3 and the much higher cost if the difference is worth it. John
Title: Re: GRS-3 vs Neo 3
Post by: virtue on 14 Jan 2022, 05:12 am
The BG8 (equiv) units have a natural roll-off under 500hz.  How does high power at low frequencies affect these things?  Is it essential to high-pass filter them?
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 14 Jan 2022, 05:40 am
The BG8 (equiv) units have a natural roll-off under 500hz. How does high power at low frequencies affect these things?  Is it essential to high-pass filter them?

I certainly would. Pushing bass frequencies, especially at higher volumes for extended periods is likely to cause them to burn up, as planar and ribbons tend to distort pretty badly as excursion requirements increase.

For -3dB point of 500Hz, I would look at a cap value of 40uF to act as a high pass filter. Then cross it over to a woofer somewhere below that point.
Title: Re: GRS-3 vs Neo 3
Post by: mkane on 15 Jan 2022, 07:57 pm
Danny did some quick testing today with the GRS-10 clone in the Super Mini baffle.
He said it was a workable alternative, it just needs a notch filter to bring down a hump around 600-700Hz by a couple dB, but seems to measure better than in my own testing.

I believe some wanted to use them to make a LineForce since they're fairly priced & BG Neo10s haven't been available, especially lately, and they should work pretty well once the changes to the crossover are made.  :thumb:

I'll update once Danny has a chance to email the measurements.

Reading this thread makes me believe I can possibly put my Super Seven top hats to use temporarily at least. I've been Jonzsen to listen to these.

Edit: read the entire thread and HAL says the 10's won't fit the baffle cutouts. It would be a real hack job if I tried to enlarge the cut-outs.
Title: Re: GRS-3 vs Neo 3
Post by: SpielbergAudio on 10 Feb 2022, 11:38 pm
This is fascinating, would be interesting to see these compared to the HiVi RT-1, and the Infinity Emit .
Title: Re: GRS-3 vs Neo 3
Post by: SpielbergAudio on 10 Feb 2022, 11:42 pm
GRS-10, GRS-8 vs Infinity Emim vs Dayton AMT-4 Pro, vs LFT-10
Title: Re: GRS-3 vs Neo 3
Post by: durwood on 5 Apr 2024, 05:27 am
Is this project still alive or is it dead? I am finally trying to put some drivers to use I have collected years ago with grand ambitions. I picked up some faceplates and now have started experimenting, just missing the back cups and was hoping to 3D print some.
Title: Re: GRS-3 vs Neo 3
Post by: Hobbsmeerkat on 5 Apr 2024, 07:00 pm
The GRS10s weren't as viable as we had hoped.

If you just need back cups, I believe I can still print some for you no problem as I still have the files necessary to print them