I've been playing around with a Rolls SX45 as low pass filter into Parasound ZAmp and two Dayton Audio SUB-1000L subwoofers.
This supports the sound of the main small speakers in my small system. It sounds surprisingly good and fast. Not hugely deep, but doesn't matter, mostly I want to add some reinforcement for the small speakers.
So, now it got me... I got these little, shallow boxes standing... and they're pretty cheap. I thought about getting four or six more and building two stacks of four up front, of perhaps put two stacks of two in front and two more -phase delayed, out of phase, in the back.... sort of creating what Trinnov calls waveforming.
https://www.trinnov.com/en/subwoofer-guidelines/
WAF is not important as this is my home office and I got a door...
Getting the woofers is easy, I got the crossover and the amps... so all I will need is the delay unit.
Well.... WAF might be a factor... when she walks in and sees those woofers eight feet up on the back wall... etc...
Any ideas... have you tried this?
This supports the sound of the main small speakers in my small system. It sounds surprisingly good and fast. Not hugely deep, but doesn't matter, mostly I want to add some reinforcement for the small speakers.
So, now it got me... I got these little, shallow boxes standing... and they're pretty cheap. I thought about getting four or six more and building two stacks of four up front, of perhaps put two stacks of two in front and two more -phase delayed, out of phase, in the back.... sort of creating what Trinnov calls waveforming.
https://www.trinnov.com/en/subwoofer-guidelines/
WAF is not important as this is my home office and I got a door...
Getting the woofers is easy, I got the crossover and the amps... so all I will need is the delay unit.
Well.... WAF might be a factor... when she walks in and sees those woofers eight feet up on the back wall... etc...
Any ideas... have you tried this?
That is awesome.... let me get my wife and tell her I'm gonna build a wall full of holes...
;-)
;-)
The idea of using many small drivers in lieu of fewer larger drivers is not new
https://www.pjbworld.com/cms/products-cabinets/
Phil Jones is the guy who started Acoustic Energy... all about small aluminum woofers...
Now, that video.... so he still needed to finish screwing those drivers on the baffle... and I might have reinforced the baffle a little bit differently, but it's an amazing idea when you think about it.
I'm now looking at the back of my office, which is all closets... hmm... I could build a cabinet with a bunch of little woofers that sits INSIDE the closet. So, when want to use it, all I got to do is slide the door. Hmm... now I gots me thinking. I could do this with minor WAF. Just gotta think how to shuffle things inside the closet.
I just need to figure out what equipment I'll need to do the delay...
https://www.pjbworld.com/cms/products-cabinets/
Phil Jones is the guy who started Acoustic Energy... all about small aluminum woofers...
Now, that video.... so he still needed to finish screwing those drivers on the baffle... and I might have reinforced the baffle a little bit differently, but it's an amazing idea when you think about it.
I'm now looking at the back of my office, which is all closets... hmm... I could build a cabinet with a bunch of little woofers that sits INSIDE the closet. So, when want to use it, all I got to do is slide the door. Hmm... now I gots me thinking. I could do this with minor WAF. Just gotta think how to shuffle things inside the closet.
I just need to figure out what equipment I'll need to do the delay...
Hiya, Tony!
I've seen this thing about active absorption, looks like the same thing... https://en.wikipedia.org/wiki/Double_bass_array
I think it sounds like a neato idea! No bass reverberance in room? But hard to have drivers / space set up for it.
I use Max / MSP for random audio processing. https://cycling74.com/downloads You can download and play with it for free, you gotta pay to be able to save stuff.
If you make one I wanna hear it...
- A
I've seen this thing about active absorption, looks like the same thing... https://en.wikipedia.org/wiki/Double_bass_array
I think it sounds like a neato idea! No bass reverberance in room? But hard to have drivers / space set up for it.
I use Max / MSP for random audio processing. https://cycling74.com/downloads You can download and play with it for free, you gotta pay to be able to save stuff.
If you make one I wanna hear it...
- A
Yep, "waveforming" is the same idea as the double bass array... taken a bit further. People are getting away with clean, low bass in smallish square rooms that normally would sound like ^$^@*...
I was thinking of putting some of the drivers in the closet behind the listening chair... in my office. You saw that. They'd be three feet behind my head but if all they do is low end frequencies I should not hear them ( no location clues with bass, huh? ).
Wiring will be easy since I got the Outlaw wireless bridge.
Would I need a PC in the loop to run cycling74.com stuff?
Yep, I'll keep you in the loop.
HEY... I just realized... I walked to the living room to look...
These are the passive "subwoofers" I was thinking about..
At a 130 bucks a pop (note they got four drivers in there) I doubt you could build them any cheaper... and they are shallow, so the fit in a nice stack against a wall.
I also got the Entecs in "storage" behind the living room couch, under the sofa table. The only issue is that they would be different from the front woofers. But.... and my wife won't see those, she's already used to them... getting power to them will be trivial and with the Outlaw I can get the signal back there.
Although, the office, being smaller, might gain more, the living room is already nice sounding.
The other room is the HT in the den. I could put the Entecs along the back wall. The main speakers already have plenty of bass and waveforming is getting traction in HT with their BOOM BOOM bass...
I was thinking of putting some of the drivers in the closet behind the listening chair... in my office. You saw that. They'd be three feet behind my head but if all they do is low end frequencies I should not hear them ( no location clues with bass, huh? ).
Wiring will be easy since I got the Outlaw wireless bridge.
Would I need a PC in the loop to run cycling74.com stuff?
Yep, I'll keep you in the loop.
HEY... I just realized... I walked to the living room to look...
These are the passive "subwoofers" I was thinking about..
At a 130 bucks a pop (note they got four drivers in there) I doubt you could build them any cheaper... and they are shallow, so the fit in a nice stack against a wall.
I also got the Entecs in "storage" behind the living room couch, under the sofa table. The only issue is that they would be different from the front woofers. But.... and my wife won't see those, she's already used to them... getting power to them will be trivial and with the Outlaw I can get the signal back there.
Although, the office, being smaller, might gain more, the living room is already nice sounding.
The other room is the HT in the den. I could put the Entecs along the back wall. The main speakers already have plenty of bass and waveforming is getting traction in HT with their BOOM BOOM bass...
Last edited:
I think Trinnov is taking it further with some type of their own processor.
Not quite sure, that's why I asked.
Looking into the HT guys, some of them are literally building a lot of woofers into the walls of their customized, dedicated theater rooms and they use Trinnov processing, all tied into their surround sound decoders.
https://www.avsforum.com/threads/tr...ll-users-with-latest-software-update.3306646/
For a simple 2 channel system, all I'd be looking for is smoothing the bass, not extending it deeper. In a small room like my office (12x13) it could make a huge difference, it the living room and den likely not as much -both rooms about 14x20.
I created this thread... let's see if those guys respond:
https://www.avsforum.com/threads/waveforming-for-two-channel-audio-what-kind-of-processor.3325537/
Not quite sure, that's why I asked.
Looking into the HT guys, some of them are literally building a lot of woofers into the walls of their customized, dedicated theater rooms and they use Trinnov processing, all tied into their surround sound decoders.
https://www.avsforum.com/threads/tr...ll-users-with-latest-software-update.3306646/
For a simple 2 channel system, all I'd be looking for is smoothing the bass, not extending it deeper. In a small room like my office (12x13) it could make a huge difference, it the living room and den likely not as much -both rooms about 14x20.
I created this thread... let's see if those guys respond:
https://www.avsforum.com/threads/waveforming-for-two-channel-audio-what-kind-of-processor.3325537/
Last edited:
To clarify, the double bass array in a theoretically ideal room doesn't need anything else, no extra processing to perform properly. The DBA is no different to a regular multi-sub arrangement except that it has been geometrically simplified. Standard multi-subs are two way (they emit and absorb) and produce results as good as you like.
I understand that.
In that mode, all we need is to send the signals from the front woofers to the back woofers, run those out of phase and delay the signal.
The trick is getting the delay right.
That's the part.
The Trinnov system is a bit more complicated, it has a processor that computes delays based upon the size of the room, location of the woofers, etc... I think it comes with a calibrated mike, etc.... I think it's overkill for a 2ch system but you never know.
And I still need to get my hands on a delay gizmo. So, I'm just interested on what kind of gizmos exist.
And naturally, my room(s) are not theoretically ideal... so the delays might have to be different.
One more thing... will this require mono bass or can I get away by sending the left and right bass signals along to their corresponding rear woofers?
In my home office, I run the low pass at 65 Hz with a 12 db/oct slope. Speakers are run full bandwidth, but they are small speakers...
In that mode, all we need is to send the signals from the front woofers to the back woofers, run those out of phase and delay the signal.
The trick is getting the delay right.
That's the part.
The Trinnov system is a bit more complicated, it has a processor that computes delays based upon the size of the room, location of the woofers, etc... I think it comes with a calibrated mike, etc.... I think it's overkill for a 2ch system but you never know.
And I still need to get my hands on a delay gizmo. So, I'm just interested on what kind of gizmos exist.
And naturally, my room(s) are not theoretically ideal... so the delays might have to be different.
One more thing... will this require mono bass or can I get away by sending the left and right bass signals along to their corresponding rear woofers?
In my home office, I run the low pass at 65 Hz with a 12 db/oct slope. Speakers are run full bandwidth, but they are small speakers...
Last edited:
Not so much the delays necessarily, but the spatial interaction. It delves into the standard multi-sub procedure to manage specific spatial anomalies with the help of an additional sub.
Standard multi-subs are overlapped with the mains, not crossed. DBA isn't in theory but it could be optionally.
The array may not operate as an array if the subs aren't in unison. IMO, stereo bass isn't as much of a problem as is often thought.
Ideally a small box.... looking for something reasonable for experimentation. Two channel delay.
I figure if I run a low pass at 65Hz, or lower, the bass is gonna be mono anyhow, huh?
The "subwoofers" I'm using have a fairly high crossover as default, so that's why I got the two way crossover and run the "sub"woofers with it.
I figure if I run a low pass at 65Hz, or lower, the bass is gonna be mono anyhow, huh?
The "subwoofers" I'm using have a fairly high crossover as default, so that's why I got the two way crossover and run the "sub"woofers with it.
Yes, but I'd wait to learn where schroeder kicks in, room modes are worth addressing. Most of our localising ability resides above 700Hz in any case.
This might work. But it still too pricey and it does too much. I just want a plain two channel delay...
https://www.sweetwater.com/store/detail/DEQ2496--behringer-ultracurve-pro-deq2496?mrkgadid=3251364500&mrkgcl=28&mrkgen=mpla&mrkgbflag=0&mrkgcat=studio&recording&acctid=21700000001645388&dskeywordid=92700046997883722&lid=92700046997883722&ds_s_kwgid=58700005286965274&ds_s_inventory_feed_id=97700000007215323&ds_a_cid=405527921&ds_a_caid=9238738029&ds_a_agid=100560911664&ds_a_lid=pla-924127079967&dsproductgroupid=4581458795425260&product_id=DEQ2496&prodctry=US&prodlang=EN&channel=Online&storeid=&device=c&network=o&matchtype=e&adpos=largenumber&locationid=&creative=&targetid=pla-4581458795425260&campaignid=283268301&awsearchcpc=1&msclkid=f4f1ffdfb82e126c76aa97f44b5e2d55&utm_source=bing&utm_medium=cpc&utm_campaign=aaShopping - Core - Studio & Recording&utm_term=4581458795425260&utm_content=Studio & Recording - Signal Processing & 500 Series&gclid=f4f1ffdfb82e126c76aa97f44b5e2d55&gclsrc=3p.ds&gad_source=7
Someone at AVS forum confirmed that the Trinnov set up is overkill.. that all I need is something like the miniDSP to do dealy, but when I look at the miniDSP page I don't see a digital delay gizmo... in one easy to use box.
I did find this...
https://www.adorama.com/hrad340.htm...&utm_source=rflaid915373&utm_medium=affiliate
https://www.sweetwater.com/store/detail/DEQ2496--behringer-ultracurve-pro-deq2496?mrkgadid=3251364500&mrkgcl=28&mrkgen=mpla&mrkgbflag=0&mrkgcat=studio&recording&acctid=21700000001645388&dskeywordid=92700046997883722&lid=92700046997883722&ds_s_kwgid=58700005286965274&ds_s_inventory_feed_id=97700000007215323&ds_a_cid=405527921&ds_a_caid=9238738029&ds_a_agid=100560911664&ds_a_lid=pla-924127079967&dsproductgroupid=4581458795425260&product_id=DEQ2496&prodctry=US&prodlang=EN&channel=Online&storeid=&device=c&network=o&matchtype=e&adpos=largenumber&locationid=&creative=&targetid=pla-4581458795425260&campaignid=283268301&awsearchcpc=1&msclkid=f4f1ffdfb82e126c76aa97f44b5e2d55&utm_source=bing&utm_medium=cpc&utm_campaign=aaShopping - Core - Studio & Recording&utm_term=4581458795425260&utm_content=Studio & Recording - Signal Processing & 500 Series&gclid=f4f1ffdfb82e126c76aa97f44b5e2d55&gclsrc=3p.ds&gad_source=7
Someone at AVS forum confirmed that the Trinnov set up is overkill.. that all I need is something like the miniDSP to do dealy, but when I look at the miniDSP page I don't see a digital delay gizmo... in one easy to use box.
I did find this...
https://www.adorama.com/hrad340.htm...&utm_source=rflaid915373&utm_medium=affiliate
Last edited:
Well, the rear array is the absorption set, right? So theoretically the bass wave front washes over you, and then meets the negative rear wave and poofs out of existence, and the room doesn't keep it around to build up.
Ya. I thought you were PC based in the office, but perhaps not.
I think the multi-sub thing is just to distribute drive and even out modes? And the DBA thing is specifically to make a planar wave front that is emitted in the front and absorbed in the rear? Have I got it wrong?
I think multi-subs are all about just evening out modal performance, so the more sources the better. But the DBA thing is aiming for a plane wave, so I think you'd want to keep the DBA output / absorption scheme pristine and not include other sources.
Sounds like a job for mini-dsp or the dayton equiv (a good deal for 8 outs, I think). I'd want more than the 2 ch out, I'd want to hi pass the main signal and keep the latency of the box constant across the system (cause you'll add delay for the subs, but the DSP box will have latency of it's own. How much? IDK!).
For a smaller room, all that stuff will start higher, but also the distance between bass drivers will be smaller, so the frequency to which the bass array output approximates a plane wave will be higher... Tony, look at the equations on the DBA wiki page and do the math based on your room / (potential) array dimensions.
It's a neato idea, if I've understood it correctly. We could do acoustic measurements to help dial in delay, trying to minimize level at the back wall. It would be fun.
I was about to post that link, not that I use it myself but it appears to be what Tony is looking for.
Correct.
However they achieve the same goals (they technically do the same thing). After all, a Rubik's cube weighs the same whether it's mixed up or solved 😉
OK.... I'll look at those little boxes. Let me see how it maps out. I could start with just a second pair of woofers.
Adam has seen my house so he knows the rooms I'm talking about. The office has two systems, the one in front of me is PC based, the other one now has a WiiM Ultra driving the DAC over USB so I can run the PC or Android or Chromebook.
I need to think, I have like five projects, just finishing the Ultra, gotta finish the op amp rolling in the P3, then I do want to build the F5m.. And I will have to unclutter the office too. And I got a job... ratz.
You guys want a Sony Super Beta (SL100HF) with the matching Laser Disc... all with shuttle wheels and editing controller? The suckers are BIG. I like Lagunitas IPA.
I wonder, for waverforming.... does the back of the room need to be closed?
Adam has seen my house so he knows the rooms I'm talking about. The office has two systems, the one in front of me is PC based, the other one now has a WiiM Ultra driving the DAC over USB so I can run the PC or Android or Chromebook.
I need to think, I have like five projects, just finishing the Ultra, gotta finish the op amp rolling in the P3, then I do want to build the F5m.. And I will have to unclutter the office too. And I got a job... ratz.
You guys want a Sony Super Beta (SL100HF) with the matching Laser Disc... all with shuttle wheels and editing controller? The suckers are BIG. I like Lagunitas IPA.
I wonder, for waverforming.... does the back of the room need to be closed?