AudioCircle

Industry Circles => GR Research => Topic started by: la80vette on 24 Aug 2021, 02:28 pm

Title: LGK 2.0
Post by: la80vette on 24 Aug 2021, 02:28 pm
When are these drivers expected to arrive?
Title: Re: LGK 2.0
Post by: Hobbsmeerkat on 24 Aug 2021, 04:04 pm
They're in production now. We're hoping to have them by October.
Title: Re: LGK 2.0
Post by: la80vette on 24 Aug 2021, 04:35 pm
Thank you. My LGK kit order is already placed.
Title: Re: LGK 2.0
Post by: Oscillate on 24 Aug 2021, 09:53 pm
"We're hoping to have them by October"


...GR Research Wedgies 2.0  :)
Title: Re: LGK 2.0
Post by: Skilly on 9 Nov 2021, 02:30 am
And Another 2 months pass by.
Title: Re: LGK 2.0
Post by: Hobbsmeerkat on 9 Nov 2021, 02:18 pm
They're on the water. And shipping delays are brutal.
Had that not been the issue, we would likely have had them by now
Title: Re: LGK 2.0
Post by: mlundy57 on 9 Nov 2021, 06:31 pm
Shipping delays are no joke. They affect everything. In our senior nutrition programs we can't get the foam cups we use to serve soups ans stews. Then when we can get the cups, we can't get lids.

To make it worse, if your shipment happens to be on a ship that has a problem, like the Evergiven, the delays are even longer. Multiply these delays by every time a prototype is sent back for additional work and the development cycle is stretched out even more. With the Neo3 driver it took around two years to get a driver developed that met Danny's requirements and product delivered. That was when everything was happening in normal time frames. It's no wonder development of the 2.0 drivers as well as others like the Neo10 are taking so long.

All we can do is be patient with everybody. Eventually we'll get there.
Title: Re: LGK 2.0
Post by: Danny Richie on 12 Nov 2021, 01:53 pm
They arrive in the port of NY in a few days. How long it takes to get unloaded and sent to us is another story. Shipping issues right now are the worst!
Title: Re: LGK 2.0
Post by: dknywinnie on 14 Nov 2021, 06:28 pm
What are the differences between LGK 1.0 and LGK 2.0?
Title: Re: LGK 2.0
Post by: tortoiseman2542 on 14 Nov 2021, 06:48 pm
They arrive in the port of NY in a few days. How long it takes to get unloaded and sent to us is another story. Shipping issues right now are the worst!

I do IT project work for the second largest logistics company in the world. There is so much stuff sitting it’s crazy. Severe container availability shortages lead to product sitting. Driver shortages lead to product sitting that is here. It’s crazy.

Robert
Title: Re: LGK 2.0
Post by: Skilly on 16 Nov 2021, 12:46 am
For those who are not familiar with the LGK 1.0. Here is a link to a nice review Ron at New Record Day did some time ago.
https://youtu.be/Efku5oMo0nY

The LGK 1.0 is gone and not to be replicated. Instead, years ago, Danny decided to Replace the LGK 1.0 with the LGK 2.0. Danny set new performance parameters and  specifications. The supplier (Peerless of India) of the single driver speaker has had difficulty meetings those requirements and further had production issues to return the finished product to GR Research. The rumor is that a limited number of the drivers were delivered and that there are proto-type "LGK 2.0" Units in the hands of a few persons. We believe that the box plans for the LGK 1.0 are not the best match for this driver. We do not know what design will be recommended. The speaker is ideal for near-field listening. These would compete with the desktop minis, in theory. That's about all I have read about it thus far.

Title: Re: LGK 2.0
Post by: Hobbsmeerkat on 16 Nov 2021, 01:22 am
They will need smaller cabinets than the original LGK1.0 did, but they also have a much better response, especially on the top, end where the originals were a little choppy.
The trick will be getting the volume and port tuned just right.

I created a design that looked like jet engine and it measured quite well, but it needs some design changes, but it also took forever to 3D print.. so I'm going to look into something a simpler to design/print. lol

Plus they look like miniature NQ woofers with a tiny copper phase plug.
(https://www.audiocircle.com/image.php?id=230032)
Title: Re: LGK 2.0
Post by: Cheytak.408 on 16 Nov 2021, 07:52 am
They will need smaller cabinets than the original LGK1.0 did, but they also have a much better response, especially on the top, end where the originals were a little choppy.
The trick will be getting the volume and port tuned just right.

I created a design that looked like jet engine and it measured quite well, but it needs some design changes, but it also took forever to 3D print.. so I'm going to look into something a simpler to design/print. lol

Plus they look like miniature NQ woofers with a tiny copper phase plug.
(https://www.audiocircle.com/image.php?id=230032)
Awesome.  Sign me up for 8!  I'm all in on these.
Title: Re: LGK 2.0
Post by: mlundy57 on 16 Nov 2021, 02:19 pm
They will need smaller cabinets than the original LGK1.0 did, but they also have a much better response, especially on the top, end where the originals were a little choppy.
The trick will be getting the volume and port tuned just right.

I created a design that looked like jet engine and it measured quite well, but it needs some design changes, but it also took forever to 3D print.. so I'm going to look into something a simpler to design/print. lol

Plus they look like miniature NQ woofers with a tiny copper phase plug.
(https://www.audiocircle.com/image.php?id=230032)

If the performance of the new drivers exceed the original that’s really going to be something. I had thr originals at the Lone Star Audio Fest three different years and everybody who heard them had to pick their jaw up off the floor.
Title: Re: LGK 2.0
Post by: mlundy57 on 16 Nov 2021, 03:07 pm
They will need smaller cabinets than the original LGK1.0 did, but they also have a much better response, especially on the top, end where the originals were a little choppy.
The trick will be getting the volume and port tuned just right.

I created a design that looked like jet engine and it measured quite well, but it needs some design changes, but it also took forever to 3D print.. so I'm going to look into something a simpler to design/print. lol

Plus they look like miniature NQ woofers with a tiny copper phase plug.
(https://www.audiocircle.com/image.php?id=230032)

Couldn’t the current cabinets be made shorter to get the proper internal volume? Or if you want to keep the height for tweeter position, add a solid brace to reduce the internal volume?
Title: Re: LGK 2.0
Post by: Hobbsmeerkat on 16 Nov 2021, 03:56 pm
Couldn’t the current cabinets be made shorter to get the proper internal volume? Or if you want to keep the height for tweeter position, add a solid brace to reduce the internal volume?

I'm sure there are things that could be done to adjust the original cabinets volume as they only require 0.11 cubic feet of airspace, but they also need smaller ports that are 1" diameter and 3" deep.
Title: Re: LGK 2.0
Post by: Skilly on 16 Nov 2021, 04:34 pm
That is so small you may have a tough time getting your crossover parts in alongside the port. The crossover has maybe two, or three parts tops, I would think. .11 Cubic feet of space? It will be the size of the old Bose Accoustimass pods?  I wonder if the port has to be rear firing? Perhaps a down firing port might be interesting?
Title: Re: LGK 2.0
Post by: Skilly on 16 Nov 2021, 04:57 pm
I am confident that smarter minds than mine are working on this but, unless I am doing this wrong, that means about 4.5 X 4.5 x 10 inches, after calculating the space for bracing. And the old box was 4.5 X 7 X 12 inches. Since Horizontal off axis can be an issue it seems like a stand would be required for it on a desk top. If great depth is needed one would have to reduce the height. So maybe 4.5 X 6.5 X 7 inches?
Title: Re: LGK 2.0
Post by: Hobbsmeerkat on 16 Nov 2021, 07:25 pm
Internal volume is 4x6.25x7.5 with 1/2 inch MDF for the walls.
And we do intend on including a stand built into the cabinet that will raise it up by another 5 inches or so.

We plan to have the port down firing within the stand section
Title: Re: LGK 2.0
Post by: Danny Richie on 17 Nov 2021, 12:11 am
Here is the measured on axis response in one of our test boxes and with the step loss correction circuit.

(https://www.audiocircle.com/image.php?id=232324)

And the spectral decay.

(https://www.audiocircle.com/image.php?id=232323)
Title: Re: LGK 2.0
Post by: hawkeyejw on 17 Nov 2021, 12:28 am
So you’re saying I need to find a thinly veiled excuse to buy and build some of these.
Title: Re: LGK 2.0
Post by: Hobbsmeerkat on 17 Nov 2021, 12:29 am
Here is the measured on axis response in one of our test boxes and with the step loss correction circuit.

(https://www.audiocircle.com/image.php?id=232324)

And the spectral decay.

(https://www.audiocircle.com/image.php?id=232323)
So you’re saying I need to find a thinly veiled excuse to buy and build some of these.
I'm already planning on building a pair myself.  8)
Title: Re: LGK 2.0
Post by: Skilly on 17 Nov 2021, 05:13 am
Very Nice! I am getting stoked  for this now.
https://www.reactiongifs.com/wp-content/uploads/2012/05/excited3.gif
Title: Re: LGK 2.0
Post by: subsonic1050 on 17 Nov 2021, 07:24 am
I'm ordering a pair the day they become available!
Title: Re: LGK 2.0
Post by: Chewbacca on 17 Nov 2021, 04:40 pm
Going to make a small system for upstairs... No doubt, these will be the speakers! Looking into the Musical Paradise MP-303 to drive them. Looks like a nice little unit for the price!
Title: Re: LGK 2.0
Post by: Hobbsmeerkat on 4 Dec 2021, 02:00 am
I 3D printed a test cabinet based on the parameters of the drivers.

(https://www.audiocircle.com/image.php?id=233218&size=xlarge)

(Its ugly cuz the print failed halfway through and I had to print the top half and epoxy it onto the good bottom half. Then i was too slow getting the bottom expoxied on, so I just used some spare filament and the side of my soldering iron to fill in the gap at the bottom.)

Having it front-ported actually allowed us to raise the sensitivity to 85db. But it was a little too shallow, so it was tuned to 86Hz instead of 80.

We're going to make some changes to its shape and port But it should be much faster to cut and assemble than the several days it took to print this one.

Currently the crossover will be mounted to the back panel.
The slotted port also likes some extra space to reflect off of and gives a smoother response in the vocal region.

I previously tested a "jet engine" style cabinet and it reduced the parts quantity by half, removing the need for one of the notch filters.

(https://www.audiocircle.com/image.php?id=233216&size=large)

It measured really well, but had its own issues too though and isn't going to be practical for most people to build.. still pretty  cool though!
Title: Re: LGK 2.0
Post by: mkrawcz on 4 Dec 2021, 02:10 am
You have my attention. I’ve wanted these speakers for 2 years now.
Title: Re: LGK 2.0
Post by: Skilly on 4 Dec 2021, 05:41 am
That first one, beside the esthetics, Looks much larger than the cubic measures that were discussed. That looks more like 4.5 X10 X 7 with a front facing port. Since it will be on a stand-like structure, it could have a down firing port? I am wondering what the material you used for the 3D printer? You must have used a ton of it to make the walls thick?

Thanks for sharing them. I kind of enjoy the work-in-progress shots.
Title: Re: LGK 2.0
Post by: nlitworld on 4 Dec 2021, 06:01 am
That jet engine design looks rad! Completely over the top and impractical for most people to build, but a painted up set of those would be a super cool one of a kind speaker.  :popcorn: You guys should keep pushing the envelope. I triple-dog dare you.
Title: Re: LGK 2.0
Post by: Hobbsmeerkat on 4 Dec 2021, 07:04 am
That first one, beside the esthetics, Looks much larger than the cubic measures that were discussed. That looks more like 4.5 X10 X 7 with a front facing port. Since it will be on a stand-like structure, it could have a down firing port? I am wondering what the material you used for the 3D printer? You must have used a ton of it to make the walls thick?

Thanks for sharing them. I kind of enjoy the work-in-progress shots.

The 4" x6.25" x 7.5" is the internal volume. So add an extra inch in each direction and you've got the external size. The walls are 1/2 inch thick.

The updated version will be 4.5" x5.75" x7.5" internally, and the port will need to be about 4" deep instead of the 2" in the current version.

I use PLA. Until this project I normally use 1KG spools. But im currently using a 3KG spool from Polymaker.

A down-firing port was the initial plan, but the front-mounted port allows for a small bump in overall effeciency
We may make both versions to see which one performs better.

I used 50% infill on the base and lower half, the upper half and top are 40% infill there's probably 1.6kg of filament in this version.

There's a bit of ringing going on at one frequency but I think it's likely just the cabinet resonances/reflections that dont exist in the original test cabinet.

That jet engine design looks rad! Completely over the top and impractical for most people to build, but a painted up set of those would be a super cool one of a kind speaker.  :popcorn: You guys should keep pushing the envelope. I triple-dog dare you.

Maybe sometime in the near future I can work on it a little more and use bondo to smooth it over some more.
But it's not in the cards at the moment.  :wink:
Title: Re: LGK 2.0
Post by: Hobbsmeerkat on 4 Dec 2021, 07:53 pm
Heres a comparison of the original LGK cabinet vs the most recent prototype. Its about half an inch wider, half an inch shallower and 2 inches shorter.

The next test cabinet will be another half inch wider and more shallow.

(https://www.audiocircle.com/image.php?id=233271&size=xlarge)

Here's the original stand i printed for it, its about 1-2 inches too tall, but it still looks pretty good tbh!

(https://www.audiocircle.com/image.php?id=233273&size=xlarge)
Title: Re: LGK 2.0
Post by: wgraft5 on 4 Dec 2021, 08:01 pm
That's really cool Hobbs  :thumb:
Title: Re: LGK 2.0
Post by: hawkeyejw on 5 Dec 2021, 01:15 am
Oh wow thanks for telling us the dimensions, that really helps put it in context. That first photo I was thinking the 1.0s were 4” taller at least, I forgot how small those drivers are!
Title: Re: LGK 2.0
Post by: mzbrahce on 6 Dec 2021, 03:42 pm
Would these work in a line source?  I'm thinking Skinny 12....
Title: Re: LGK 2.0
Post by: Danny Richie on 6 Dec 2021, 05:02 pm
Would these work in a line source?  I'm thinking Skinny 12....

They can be used in an array.