Title says it all. This will be a build in progress.
It absolutelly should have a completely perfect and uniform dispersion, very low thd, very, very low imd through the whole range. It will be built in a wall, left and right to the tv. I expect the left channel to be about 6db max reinforced through the whole range, should be an easy fix.
This means that every single possible reflection should be spectrally as close to the front wave as possible.
The left and right notch in the wall will be filled with drywall, spaker goes inside.
This kind of directivity is what I believe I can pull off with this.
We'll see.
Every GRS sub will have a 100W rms ljm mx50se ab class amp. All other drivers will be driven by 30w rms D class amps, each driver it's own amp.
Subs will be naturally full vibration and even order distortion cancelling.
It absolutelly should have a completely perfect and uniform dispersion, very low thd, very, very low imd through the whole range. It will be built in a wall, left and right to the tv. I expect the left channel to be about 6db max reinforced through the whole range, should be an easy fix.
This means that every single possible reflection should be spectrally as close to the front wave as possible.
The left and right notch in the wall will be filled with drywall, spaker goes inside.
This kind of directivity is what I believe I can pull off with this.
We'll see.
Every GRS sub will have a 100W rms ljm mx50se ab class amp. All other drivers will be driven by 30w rms D class amps, each driver it's own amp.
Subs will be naturally full vibration and even order distortion cancelling.
I know. I've built 2 4-way full range dipole systems. lx521 and my own design.
These will be flat/flush installed in the wall itself. There is no back wave to speak of. With full 2pi radiation these should do, it's equivalent to 4pi radiation of a standing speaker. And so they should behave as omni's in the room. No dipole action here at all.
These will be flat/flush installed in the wall itself. There is no back wave to speak of. With full 2pi radiation these should do, it's equivalent to 4pi radiation of a standing speaker. And so they should behave as omni's in the room. No dipole action here at all.
I see. So essentially you are making in the wall speakers. Picture of your speaker is confusing.
But in the wall speakers ratiating half the space to the room are not omni.
But in the wall speakers ratiating half the space to the room are not omni.
Yes, hence the quote marks, "omni".
I would suspect that such a half space radiation coming from walls is pretty much the same or better than a true omni.
Thanks!
I would suspect that such a half space radiation coming from walls is pretty much the same or better than a true omni.
Thanks!
Like a Omni close to the wall, with sound absorbing foam on the wall to reduce reflections? Perhaps a tweeter "lens" like that used on the Band and Olufsen Beolab 9 would be worth trying.
Something like that, only the sponge is perfect absorber in this case, and the speaker itself is a true omni 20-20k, both in vertical and horizontal planes. I've thought about these lenses, diffusors, redirectors, I can't see how that works reliably enough. Interesting ideas for sure though.
Sorry about the long delay, I got a son, and we're all hectic right now. My wife almost died during labour but all is well now.
It's all built, I'm currently working on a 12 channel amp for it, time permitting 🙂
The tv is 185cm long diagonally to give you some idea of the space (wide angle lens distortion and so)
It's all built, I'm currently working on a 12 channel amp for it, time permitting 🙂
The tv is 185cm long diagonally to give you some idea of the space (wide angle lens distortion and so)
It's finally done. I'll just paste an imgur album link here, it's a hassle to embed everything manually.
I've eq-ed the sub bass and did some more tests.
This is the horisontal directivity plot. I'll do vertical later but it won't be very different. There isn't any data for 90+ cause there isn't 90+, it's a wall.
This is the final EQed listening postition FR, all over the sofa - see following.
Decay, listening position, upper line is the worst offender, still 40 db below.
Excess GD for speaker.
Excess GD subs. Small resonance at 55 hz.
Subs. Small 55 hz resonance.
Low mid box.
High mid box. Tweeters are perfect, but that's pointless.
Subs distortion, 80db. Can't do proper ground plane so no proper complex pulses testing I'm afraid.
Listning position spectrum after EQ.
Listening positions (all around the sofa) before EQ.
Some other room positions.
All spots on sofa, after EQ.
With some other room spots.
Cross to the low mid woofer.
This is the horisontal directivity plot. I'll do vertical later but it won't be very different. There isn't any data for 90+ cause there isn't 90+, it's a wall.
This is the final EQed listening postition FR, all over the sofa - see following.
Decay, listening position, upper line is the worst offender, still 40 db below.
Excess GD for speaker.
Excess GD subs. Small resonance at 55 hz.
Subs. Small 55 hz resonance.
Low mid box.
High mid box. Tweeters are perfect, but that's pointless.
Subs distortion, 80db. Can't do proper ground plane so no proper complex pulses testing I'm afraid.
Listning position spectrum after EQ.
Listening positions (all around the sofa) before EQ.
Some other room positions.
All spots on sofa, after EQ.
With some other room spots.
Cross to the low mid woofer.