New GR Neo 3 tweeters are here.

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corndog71

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Re: New GR Neo 3 tweeters are here.
« Reply #80 on: 12 Oct 2017, 01:30 pm »
Does it have to be open baffle?  Just thinking back inside the box.

Danny Richie

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Re: New GR Neo 3 tweeters are here.
« Reply #81 on: 12 Oct 2017, 03:34 pm »
Does it have to be open baffle?  Just thinking back inside the box.

No, you can put the tweeters in their own little air space and use them in sealed or ported designs.

corndog71

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Re: New GR Neo 3 tweeters are here.
« Reply #82 on: 12 Oct 2017, 07:09 pm »
So the question you answered was these speakers can't be recreated with an MDF cabinet.  I guess what I'm asking is could a similar speaker be done but with a solid back cabinet. 


Danny Richie

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Re: New GR Neo 3 tweeters are here.
« Reply #83 on: 12 Oct 2017, 07:46 pm »


There is just not enough material there to CNC it out of MDF. The frame would become so weak that it would almost snap under its own weight.

Danny Richie

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Re: New GR Neo 3 tweeters are here.
« Reply #84 on: 12 Oct 2017, 07:51 pm »
A similar speaker could be built with a sealed back, but it would still really need a baffle made from Aluminum or something just as strong.

*Scotty*

Re: New GR Neo 3 tweeters are here.
« Reply #85 on: 12 Oct 2017, 08:03 pm »
I wonder if Corian or clone of similar material could be used. If the depth of the thinest portions between the panels was increased maybe there would be enough strength to stay in one piece. Also a series of aerodynamic D shaped supports could be glued across the back like the rungs of a ladder to increase the strength of the panel.
Scotty

Keithh

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Re: New GR Neo 3 tweeters are here.
« Reply #86 on: 12 Oct 2017, 08:12 pm »
Don't know if they still make it, but Appleply used to make a plywood that looks like
Baltic Birch but was much heavier and stiff as a steel plate. Picking up a 3/4" sheet of it
had to be as heavy as 2 sheets of 3/4" MDF. It was the nicest plywood I have ever
worked with.

It was an expensive special order product and the buyer at work said it could be made in any
thickness up to 3". But I have not seen any in years so it might be another great product CARB
regulations killed off.

Oscillate

Re: New GR Neo 3 tweeters are here.
« Reply #87 on: 12 Oct 2017, 09:35 pm »
"...but it would still really need a baffle made from Aluminum or something just as strong."

I understand. What I was thinking was a 1/8" thick front baffle made of aluminum or steel
plate. The remainder of the thickness of the baffle could be of MDF or wood that the metal
plate was fastened onto.

I think a lot of us 'hobbyists' could easily work with 1/8" thick metal plate without special tools.

...come to think of it, you could also sandwich MDF or wood between two metal plates?

Danny Richie

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Re: New GR Neo 3 tweeters are here.
« Reply #88 on: 12 Oct 2017, 10:38 pm »
Yeah you might be able to figure out ways to sandwich materials, but the real cost is the CNC milling. While the Aluminum is not cheap, it's worth it.

Ric Schultz

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Re: New GR Neo 3 tweeters are here.
« Reply #89 on: 13 Oct 2017, 12:08 am »
Again, I will say you do not need aluminum to make a great line source speaker with Neo 10s and 3s.  Look at this thread again:
http://www.audiocircle.com/index.php?topic=142235.0

He is using two 3/4 inch pieces of 13 ply birch plywood and a piece of 3/4 inch highly refined particle board with green glue in between all layers.  This is very rigid....is it as rigid as much thinner aluminium?  who knows.  His speaker can be made to look much better with veneering and just a small layer of felt around the front drivers....it would look very good.  You could also round and flare or sculpt the top or bases, etc, etc.  It can look as good as your imagination allows.  He did not care what they looked like (has his own basement) and therefore spent no time on looks.  You can also flare out the backs of the baffle where the drivers are to give the drivers more air to breath and more dispersion....still, I would put felt in those flares to smooth the response and, of course, felt on the wing.

I have no doubt that these speakers sound better than the big ones Danny made with the aluminum baffles because the xover parts and wire and connectors (none) are way more transparent than what Danny uses.  Maybe an aluminum baffle would give you 5 percent better sound?  Certainly the better xover parts, wire and no connectors would give you 20% better sound.

My friend Miguel, who owns the aluminum speaker that Danny had built for him, is ordering better xover parts and wire now and I am sure he will be thrilled with the difference.  The original idea for that line source speaker came from me.  I sold Miguel on the idea and made him a super modded Behringer xover to tri-amp the speakers with.  Miguel decided he wanted an aluminum baffle and tried to find someone to make it for him.  Since he as buying the servo woofs and amps from Danny he called him and they talked and that is when Danny decided to help Miguel with his "dream speaker" and then Danny could then bring out a new model of Serenity speaker based on this proto.  The next speaker up from the "super 7" that Danny had imagined was an over $100,000 monster made from carbon fiber and had a ton of drivers.....see this thread: 
http://www.audiocircle.com/index.php?topic=110891.0

Bottom line is you can make a seriously great (and great looking) line source using Neo drivers using 16 ply birch and highly refined particle board mit green glue.  Even the one shown with 4 Neo 10s is 96 db efficient and kicks butt.  About $3700 for the Neo 10s and 3s for a stereo pair (4 Neo 10s and 12 Neo 3s per side)....add woofs and amps (three servo 12s per side) and xover and wood and felt and veneer and xover parts and wire and you are looking at about $7000 total with everything.  Not cheap but oh my....what sound you would have.  My home made speakers use one Neo 10 and one Neo 3 per side and with great xover parts, felting, wire and no connectors (all on open baffle) it sounds really, really great.  I have no speaker envy.

ebag4

Re: New GR Neo 3 tweeters are here.
« Reply #90 on: 13 Oct 2017, 12:20 am »
I have contacted Protech Composites, I am thinking about using carbon fiber panels sandwiching a plywood middle.  Very early, no pricing yet.  It would make sense to price out the aluminum and CNC work to determine what that costs as a reference. 

Concerns for me using something other than aluminum where the drivers are screwed to the baffle are the tight tolerances and the possibility of other materials breaking out where the screws are very close to the interior edge, especially on the small braces between the drivers.

The drivers cost is known, Danny, can you give us an estimate of what the crossover costs would be?

Best,
Ed

Danny Richie

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Re: New GR Neo 3 tweeters are here.
« Reply #91 on: 13 Oct 2017, 02:20 pm »
Ric, While your sandwiched wood frame does hold the drivers it also added surface reflections due to the necessary added width. The added dept also effects the drivers response. And it takes a little more than just throwing more expense into the crossover area to achieve the best sound. More importantly than that is for the crossover to be properly designed. And for these drivers, and used in this way, a first order crossover is simply not adequate for the job. Also a lack of a side wing will cause a peak in the response in the lower range. The side wing shifts it into the range where the Neo 10's are rolling off and extends their response. You might want to keep experimenting with that.

And I wouldn't be so quick to judge how something sounds until you've heard it.

Also, that model was already on the drawing board before I was contacted by Miguel. And I don't recall consulting you on the design. It was actually a variation of an in-wall version that was offered by BG. I even talked with them about doing an open baffle version a couple of years before this project started. So really Igor Levitski (the designer of the drivers) came up with and designed the first speaker to use these drivers in this way.  And my friends Igor and Pablo (owner of Dia-ichi and manufacturer of the drivers) came here to hear what I designed.  So you could say that you know a guy that is friends with the guy that designed these drivers and this speaker configuration.

orientalexpress

Re: New GR Neo 3 tweeters are here.
« Reply #92 on: 13 Oct 2017, 02:53 pm »
'How much does a pair aluminum  Frame cost?if we're have enough order for a group buy that be awesome  :thumb:
I'm in

Danny Richie

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Re: New GR Neo 3 tweeters are here.
« Reply #93 on: 13 Oct 2017, 03:44 pm »
'How much does a pair aluminum  Frame cost?if we're have enough order for a group buy that be awesome  :thumb:
I'm in

That's a good idea. I need to find a new supplier for them and I have a local company that I have worked with in the past that did a great job with CNC Aluminum milling. Let me see what I can do.

Keithh

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Re: New GR Neo 3 tweeters are here.
« Reply #94 on: 13 Oct 2017, 04:08 pm »
Is there any reason that frame needs to be made by CNC?

CNC is the way to go if there big demand, but they also could be milled manually, cast, welded or glued up with adhesives.
Adhesives could be a great DIY way as the precut strips and pieces of aluminum would be fairly inexpensive.

Ric Schultz

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Re: New GR Neo 3 tweeters are here.
« Reply #95 on: 13 Oct 2017, 07:39 pm »
Ric, While your sandwiched wood frame does hold the drivers it also added surface reflections due to the necessary added width. The added dept also effects the drivers response. And it takes a little more than just throwing more expense into the crossover area to achieve the best sound. More importantly than that is for the crossover to be properly designed. And for these drivers, and used in this way, a first order crossover is simply not adequate for the job. Also a lack of a side wing will cause a peak in the response in the lower range. The side wing shifts it into the range where the Neo 10's are rolling off and extends their response. You might want to keep experimenting with that.

And I wouldn't be so quick to judge how something sounds until you've heard it.

Also, that model was already on the drawing board before I was contacted by Miguel. And I don't recall consulting you on the design. It was actually a variation of an in-wall version that was offered by BG. I even talked with them about doing an open baffle version a couple of years before this project started. So really Igor Levitski (the designer of the drivers) came up with and designed the first speaker to use these drivers in this way.  And my friends Igor and Pablo (owner of Dia-ichi and manufacturer of the drivers) came here to hear what I designed.  So you could say that you know a guy that is friends with the guy that designed these drivers and this speaker configuration.

Using felt on the front gets rid of surface reflections and the xover I designed for Harold's speaker was not 6db per octave....it is 12db per octave.  And his speaker has a wing on it.  Where did you get the information that it does not have a wing and that it is 6db per octave?  The thread clearly shows the wing and the 12 db per octave xover.  My own speaker using one Neo 10 does not have a wing.....but it is flat to 300hz and works perfectly with two of your M165X woofers per side.  My xover between the Neo 10 and Neo 3 is also 12 db per octave.

studley

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Line force questions
« Reply #96 on: 14 Oct 2017, 09:59 am »
Danny
What's their sensitivity and what does the impedance curve look like?

Also, how far off the floor does the bottom edge of the lowest Neo 10 driver need to be?  Just thinking about floor bounce and overall height.

Danny Richie

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Re: Line force questions
« Reply #97 on: 14 Oct 2017, 06:04 pm »
Danny
What's their sensitivity and what does the impedance curve look like?

Also, how far off the floor does the bottom edge of the lowest Neo 10 driver need to be?  Just thinking about floor bounce and overall height.

Sensitivity was 97db.

It is a pretty flat impedance with a minimal drop of 3.9 ohms.



And I think I had the first Neo 10 starting about 8" off the floor. It could a little higher though. In the range that they cover the floor distance won't have a lot of effect.

studley

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Re: Line force questions
« Reply #98 on: 14 Oct 2017, 06:12 pm »
Sensitivity was 97db.

It is a pretty flat impedance with a minimal drop of 3.9 ohms.



And I think I had the first Neo 10 starting about 8" off the floor. It could a little higher though. In the range that they cover the floor distance won't have a lot of effect.

Nice easy load

Skeeboingen

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Re: New GR Neo 3 tweeters are here.
« Reply #99 on: 17 Oct 2017, 11:07 pm »
Is there any reason that frame needs to be made by CNC?

CNC is the way to go if there big demand, but they also could be milled manually, cast, welded or glued up with adhesives.
Adhesives could be a great DIY way as the precut strips and pieces of aluminum would be fairly inexpensive.

I wondered this as well.  Hardware stores like Home Depot and Lowes sell angled and flat pieces of aluminum that could be screwed and glued together.  Why wouldn't this work?

~S