Thanks for your valuable contribution. I do think a 3 speaker open baffle is something to look at.
When you live outside of the city in half open spaces.....maybe. But this will be in a closed building in the city center.
Or if you are a bus driver..... 😂
Is a center speaker supposed to just sum left and right? Or just play the shared L+R minus the signal unique to L or R?
But if you go there you would also want to subtract all or part of the signal that comes out of the center channel from the left and the right speakers..... Are there ready solutions for this?
Yeah see links on my previous post, it's called "stereo matrix". Any AV receiver likely has something built in. Any flexible DSP should be able to do it, like ADAU series chips that you can configure using SigmaStudio. I assume any computer based solution would work, like CamillaDSP. Some ~expensive pro audio DSP could do it.
See this thread for example, it might have some hints how to do it:
https://www.diyaudio.com/community/...-equations-for-3-speaker-stereo-matrix.222881
edit. yeah https://www.diyaudio.com/community/...r-3-speaker-stereo-matrix.222881/post-3573325
Here is how to do it passively using just two amplifier channels:
http://elias.altervista.org/html/SingleSpeakerStereo.html
Just read the page carefully! Do not use class-D amps for this! The page is for single speaker stereo, but same stereo matrix ought to work fine for what you've planned, three speaker stereo. The single speaker stereo concept works nicely as well, at least in small format and small room.
See this thread for example, it might have some hints how to do it:
https://www.diyaudio.com/community/...-equations-for-3-speaker-stereo-matrix.222881
edit. yeah https://www.diyaudio.com/community/...r-3-speaker-stereo-matrix.222881/post-3573325
Here is how to do it passively using just two amplifier channels:
http://elias.altervista.org/html/SingleSpeakerStereo.html
Just read the page carefully! Do not use class-D amps for this! The page is for single speaker stereo, but same stereo matrix ought to work fine for what you've planned, three speaker stereo. The single speaker stereo concept works nicely as well, at least in small format and small room.
Last edited:
If you want a more modern sound than the old Altec, the big JBL Cinema systems like the 4722 are also very good sounding and look impressive. Especially if you combine them with the massive 4642A subs that JBL sells with it. This is a home setup picture from the internet. These are build to fill big spaces with good sound, not only a sweetspot and they do work.
Making this your system will attrackt people, as JBL is still a big name and the look appeals to many. But most listening bars lean on old designs like from Tannoy and Kiplish, that are not neutral or low distortion, but live on hype... If i would do it, would use JBL cinema rig like this, but adapted to the space i have. Or if i do it diy (not so easy, name brand of system is also a customer attracking facrtor and they will sound a lot better than any Tannoy or Kiplishhorn will.
The old Altec Lansing VOTT is also a good id, but it has a certain oldskool sound that does not fit everyone and i would not call it hifi. It's good sounding lofi (hifi from the prehistory), not hifi in a modern sense of the word. But in Japan (where listening bars started) it's still that kind of old systems or variations of it that rule listening bars. Older JBL systems are also popular, Bust Western Electric or Altec Lansing are magical names there.
Making this your system will attrackt people, as JBL is still a big name and the look appeals to many. But most listening bars lean on old designs like from Tannoy and Kiplish, that are not neutral or low distortion, but live on hype... If i would do it, would use JBL cinema rig like this, but adapted to the space i have. Or if i do it diy (not so easy, name brand of system is also a customer attracking facrtor and they will sound a lot better than any Tannoy or Kiplishhorn will.
The old Altec Lansing VOTT is also a good id, but it has a certain oldskool sound that does not fit everyone and i would not call it hifi. It's good sounding lofi (hifi from the prehistory), not hifi in a modern sense of the word. But in Japan (where listening bars started) it's still that kind of old systems or variations of it that rule listening bars. Older JBL systems are also popular, Bust Western Electric or Altec Lansing are magical names there.
Does this only apply to VOTTs in their original form or also when the cabinets have been braced and damped, and the crossovers redone or replaced by an active setup? I would not even contemplate to use a VOTT without modernisation.
Fascinating stuff, lots of learning ahead.
My preliminary idea now is:
Long room with 3 open baffle speakers in the center creating two listening areas in one room with one system.
Use some kind of analog or digital 2 to 3 channel matrixing to create a fixed in stead of phantom center image.
Use room dimensions that spread out room modes over different frequencies. Possibly angle the walls and ceiling a little to avoid parallel surfaces.
Use building materials that aren't too reverberant but don't overdo it and create a dead room.
Raise the floor level at the ends of the room so for guests further away from the speakers the high frequency direct sound isn't blocked by other guests in the front.
That does look the part indeed. Very nice.
One of the reasons I am looking at open baffles though is the fact that it halves the problem of catering to many people in a large space. Imagine having a room of 12x7meter with 50 people in it. Open baffle would be like placing a mirror wall right behind the speakers and now you have a 24x7meter room with 100 people without any extra complication.
I guess you could go bipole and place two sets of JBLs back to back in the middle of the room.....but then you need two complete systems in stead of just one.
I like these though:
Last edited:
The woofers don't go low enough and the tweeter not high enough to modern standards. For the rest they fit, but to have a real modern sound they need a supertweeter and a subwoofer (support on the extremes of the frequency response) because at that time it was not really an issue to go that far. If you look at the published measurments you see that the bass response is more likje 50Hz or higher F3, and the top end start to fade fast above 10kHz with an 288 compression driver of that time. This is a measurment of Joseph Crowe of a 288 in a multicell horn like typically on a Altec VOTT system:
But even with this limitations, they do sound wonderfull good, still today. It's like a hi end lofi sound...
Is placing speakers back to back in the middle of the room ever the right thing to do? MEHs tend to be placed high up, firing diagonally down, so they reach everyone. One in each of the four corners of the room, firing towards the audience should work well.
This sounds like 90% of the wine bar, whiskey bar, cocktail bar, jazz bar, and tasting room establishments I go to. That said, you’re dedicating a disproportionately large amount of your budget to audio if audio is not your shtick.
If music isn’t your focus, you could save a lot of money by not building a concert hall with a bar and instead renovate something and install some nice JBL 70v speakers throughout. If you’re not a “listening bar”, no one will really care how good the music sounds so long as it’s not terrible. Gorgeous wait staff will bring in more customers than beryllium tweeters.
That said, if audio really is your focus despite what you say, embrace it. Build your concert hall with a bar and a stage. Book live events/bands and play good music the rest of the time. Rent it out as an event center for weddings, etc.
Berrillium tweeters and so are absolutly not needed, not even in a listening bar. You're better of with speaker that can have a wide dispertion in a controlled way, and horns are better at that than dome tweeters (even in a waveguide). It's not necesairly about volume, but about a wide zone of a decent sound you need, with as little beaming as possible.
That is why i think those old Kiplish and Altec (and in lesser degree old JBL) systems are so popular, they were made for bigger spaces (theaters), not as hifi system. And they work better in big spaces.
You don't need those old systems, but you need to have the same good even spread of sound. That's why i recommended the JBL Cinema system. It's not the most hifi (in the sense of neutral) at all (but it sounds very good), but it works very well in big spaces to spread the sound even. It's certainly not the only option, but it's much better than an OB or a more common modern small woofer floorstander system for this purpose. There are a lot of diy systems tha work similar, from the Calpamos design to the Econowave systems and so on if you want to go diy.
That is why i think those old Kiplish and Altec (and in lesser degree old JBL) systems are so popular, they were made for bigger spaces (theaters), not as hifi system. And they work better in big spaces.
You don't need those old systems, but you need to have the same good even spread of sound. That's why i recommended the JBL Cinema system. It's not the most hifi (in the sense of neutral) at all (but it sounds very good), but it works very well in big spaces to spread the sound even. It's certainly not the only option, but it's much better than an OB or a more common modern small woofer floorstander system for this purpose. There are a lot of diy systems tha work similar, from the Calpamos design to the Econowave systems and so on if you want to go diy.
In Thailand building costs aren't so high. And I prefer doing it that way for so many reasons. You can design for proper workflow, cool room, customer toilets, separate supplier entrance etc.... So while I am at it I might as well spend a few percent extra to make it properly sound insulated to the outside and acoustically optimized inside.
And even if customers don't care I do! But in business it is wrong to think "they don't care". That may by and large be a correct statement. 98% of guests may not care much. But the 2% that do become regulars and evangelists. My city has half a million people so if I reach all of the 2% I have 10.000 regulars...... Multiples of what I could handle. Thinking audiophile sound is pearls for the swines is very short term thinking. But it is a modern way of thinking that doesn't make the world a better place.
UPDATE:
I have a system figured out and started cutting wood.
The envisioned room will be 8x24x3 meter. There will be 5x straight open baffle line arrays in the center of the room creating two 8x12m listening spaces.
Each line array has 6x15" woofers, 18x4.7" vintage alnico fr drivers and a ESS heil AMT 1 tweeter.
The digital source will go in to a miniDSP flex 8 which will handle crossovers, eq and room correction. The MiniDSP will feed 3x Schiit Syn surround pre amps that have analog circuitry to create 5.1 surround from a stereo RCA input signal and have controls to effect how the signals are routed and can switch between stereo and 5.1 on the fly.
So when it is not busy and there is enough sweet spot space available for customers I can run 2 speaker stereo. When it gets busier I can switch to using 5 speakers.
I have a system figured out and started cutting wood.
The envisioned room will be 8x24x3 meter. There will be 5x straight open baffle line arrays in the center of the room creating two 8x12m listening spaces.
Each line array has 6x15" woofers, 18x4.7" vintage alnico fr drivers and a ESS heil AMT 1 tweeter.
The digital source will go in to a miniDSP flex 8 which will handle crossovers, eq and room correction. The MiniDSP will feed 3x Schiit Syn surround pre amps that have analog circuitry to create 5.1 surround from a stereo RCA input signal and have controls to effect how the signals are routed and can switch between stereo and 5.1 on the fly.
So when it is not busy and there is enough sweet spot space available for customers I can run 2 speaker stereo. When it gets busier I can switch to using 5 speakers.