Servo.... the future in bass in servo.... closed loop.... no need for stinkin' eq or digital stuff... just a nice low pass filter with a good servo controlled woofer.
@limono Put your speakers where they sound good... don't put them where they "look good" and then try to fix it with the 'software'. (1)
Aim for just enough good bass..... don't aim for lots of sloppy bass. Ideally, you should not HEAR the bass, it should all sound like music... coherent from across the entire audio spectrum. (2)
That old "fix it with the software' doesn't work. Trust me... I've been doing soft/firmware for 45 years... it just doesn't work. Get the hardware done right first!
(1) Well, in your small space, you might have to compromise... but it sounds to me like your problem is the location of your speakers, even if you put a mid-woofer to ease the transition between the mains and woofers... you still have them in the wrong place. Maybe smaller woofers, moved a little away from the side walls might help?
(2) I dial the volume for the woofers differently for the DAC and the LPs. Either way, I turn it up until I "hear" the bass, then I back it down a little bit so the whole thing sounds like a single speaker. The effect is really good... deep bass but with great dynamics and soundstage. The drum kit and bass guitar stay in place. The contrabasses stay nicely to the right and the timpani floats over the hall.
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Servo & closed loop bass is an old technology - it never took off. Cause a) we are not sensitive to THD at low frequencies and b) the ROOM does the worst to low frequencies. Servo doesn't hepl a bit here.
So you need your stinkin DSP to do your last perfections AFTER doing the hardware right (= positioning and amount of subwoofers, good crossover).
In this case the woofer hardware is good (ScanSpeak in closed cabinet) but not proper hardware installation (positioning) and bad software implementation (wild filtering, no phase adjustment) 🤓
Pfft... my Linn LP12 is also "old" technology... but it beats, hand down, Red Book digital. Only 24/96 comes close to it.
Servos didn't take off because they are "EXPENSIVE".... it is expensive to fix things in the hardware and to put the speakers in the right place to begin with. All you need is a nice low pass filter, and perhaps a high pass filter if you want to put the main speakers through it ( I don't, I run the main speakers full range ).
I also don't need phase adjustments as I run the woofers just below the main speakers and I manually position them to present a time aligned front face.
A lot of DSP is just "fixing it in the software"... just people being lazy.
Most of the market for "subwoofers" is the HT crowd and they like to feel the BOOM... BOOM... BOOM.... they tend to be cheap too... they want a 15 inch driver in a big box for 800 bucks, tops, and they want to see/feel the money they just spent in action!
Although for HT, positioning the drivers for best sound is more problematic as there is the multichannel soundstage to be aware of, so in most rooms it becomes a conflict between the best acoustic room location for a speaker and the best soundstaging location for the soundfield. I can see where in such locations, being as it may that the sound source is digital to being with, DSP usage is very useful. Note though, the if you plan the room to begin with, you won't need much, if any, processing to satisfy room loading and soundstaging.
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Do you really comprehend what’s going on in the room and what multi-sub approach can bring you? From what you write it doesn’t seem so.
Hmm... we rebuilt the house to the studs, added more space, added lots of dedicated AC homeruns.. calculated the acoustics of the rooms while doing the design, then found the best places for the speakers and couches, oh.. and we used double layered drywall with acoustic drywall and/or plywood (for quake shear wall strength - which helps a lot with controlling bass energy too )...
Also, my main 2ch rig uses TWO Entec woofers... my den's HT uses two PSB Gold-i ( described by PSB as a minimonitor on top of a subwoofer ).. that makes it TWO subwoofers..
I defeated all audio processing in our Emotiva pre/pro. The main 2ch and HT rigs are off by ~7" the center line... Maggies are four feet from the wall, no need for stinking woofers... Audio Notes and Entecs are on the same plane... heck I've ended up using the Entecs as the base for the ANs... perfect height.
We have very smooth audio response in the den and living room. You can walk around and not hear any unevenness of bass response at all. Heck with the Maggies, the dining room, room adjacent to living room, the sound of the 2ch system is outstanding as well. No booms! No suck outs!
Obviously, I do know a bit about this stuff. Been doing this since, oh... hmm... lemme see, my first stereo back in 75. First equalizer, with calibrated mike, white/ping noise generators and frequency display, in '84. First HT system with room/time correction in '92...
Now, do you want to repeat what you said?
BTW, would you like to describe what have you done to your house to set up your 2ch rig? Your HT? To make sure the audio systems and the rooms match each other well?
Huh?
Also, my main 2ch rig uses TWO Entec woofers... my den's HT uses two PSB Gold-i ( described by PSB as a minimonitor on top of a subwoofer ).. that makes it TWO subwoofers..
I defeated all audio processing in our Emotiva pre/pro. The main 2ch and HT rigs are off by ~7" the center line... Maggies are four feet from the wall, no need for stinking woofers... Audio Notes and Entecs are on the same plane... heck I've ended up using the Entecs as the base for the ANs... perfect height.
We have very smooth audio response in the den and living room. You can walk around and not hear any unevenness of bass response at all. Heck with the Maggies, the dining room, room adjacent to living room, the sound of the 2ch system is outstanding as well. No booms! No suck outs!
Obviously, I do know a bit about this stuff. Been doing this since, oh... hmm... lemme see, my first stereo back in 75. First equalizer, with calibrated mike, white/ping noise generators and frequency display, in '84. First HT system with room/time correction in '92...
Now, do you want to repeat what you said?
BTW, would you like to describe what have you done to your house to set up your 2ch rig? Your HT? To make sure the audio systems and the rooms match each other well?
Huh?
Btw - I built a non environment room for my listening room. (Ceiling, side walls and rear wall full range absorbtion, rest reflective). With speakers and monitor integrated in the front wall. Low frequency drivers build a (sloppy) single bass array (there is a post to find) and in the back is 50-100cm absorption. (moveable absorber walls).
That's probably not the room you want as living room 🙂 but you really can hear (and mix/master) the music with very little influence. And compare speakers, drivers and measure them.
The home cinema corner from the other pictures is just for fun - serious listening happens in the serious room.
That's probably not the room you want as living room 🙂 but you really can hear (and mix/master) the music with very little influence. And compare speakers, drivers and measure them.
The home cinema corner from the other pictures is just for fun - serious listening happens in the serious room.
I won't repeat it 😊 but you seem to try to convince people that EQ'ing in time and level as per DSP in a multi-sub arrangement isn't necessary. But you don't deny it is an if not the most efficient way to get an even bass response (and a good one) in a normal room, do you?
Near field listening is a whole different ball of wax. Priorities really change. Imaging and driver integration are most important. That's why smaller boxes, with tightly coupled drivers, and accurate mid bass, mid range and treble are so important. You really HEAR the speaker, not the room. (*)
In our home offices, I set up a pair of Acoustic Energy AE1s with a Nuforce DDA 100/120 to drive Tidal off the USB.
The speakers are on a shelf, right above the monitor, on their sides with the tweeters inboard, in a four foot equilateral triangle. In such a set up, I'm not too worried about deep bass, I'm just listening to the imaging, which is outstanding.
(*) I've been thinking of moving my desk away from the wall, so I get three feet from the speakers to the back wall.... that would allow me to get a set of mini Maggies.... hmm....
What is a normal room?
One that has good acoustics or one that has bad acoustics?
As always, a simple, inexpensive system will sound better in a good sounding room than a complex, expensive system in a bad sounding room.
Equalization in a good sounding room might work fine.... but, this is DIYAudio... where simple circuits rule... keep it simple, fix the room and enjoy the sound.
A normal room in this case is any room that shows modest to severe modal behavior, leading to about +/-10dB level changes over limited low frequency ranges at various if not most positions in room, when driven with one or two monopole sources. This applies for just about all domestic rooms.
But you know that, with your experience. You also know these room modes are pretty persistent and not easily if not hardly damped with passive solutions. Even anechoic test rooms (you know, the ones with foam wedges >1m) suffer from them. Passive bass traps only offer a limited solution. Optimizing source positions only works for a limited listening area. Which all of course is just fine. But we better not deny that ‘modern’ solutions like DBA and multi sub do better in all normal rooms.
But you know that, with your experience. You also know these room modes are pretty persistent and not easily if not hardly damped with passive solutions. Even anechoic test rooms (you know, the ones with foam wedges >1m) suffer from them. Passive bass traps only offer a limited solution. Optimizing source positions only works for a limited listening area. Which all of course is just fine. But we better not deny that ‘modern’ solutions like DBA and multi sub do better in all normal rooms.
You keep changing the subject and modifying your premise.
Now a "normal" room is a bad sounding room. I guess my rooms are Ab Normal.
And then you use words such as "applies for just about all domestic rooms" which simply negates your argument. What is "just about all"? How do you measure that? 10%, 50%, 90%?
The truth is simple, work on the room: select a room that has reasonable acoustics, select an audio system that can work in that room (1) and move from there. Add acoustic traps and treatments as a last resort.
Matching the audio system to the room's capabilities should be your first and foremost concern if you want good sound (even frequency response, soundstaging, detail..).
If your room sounds bad in the bass.. then adding -willy nilly- one (or more) subwoofers is a recipe for disaster. Even with equalization you are going to end up with a very spotty, uneven frequency response. If you put one (or several) woofers around the room (2) you are going to destroy the integration between the main speakers mid bass and the subwoofers.. time alignment will be destroyed. If you use digital filters... well, you have just digitized what should be a nice and simple audio system. You've added a host of other problems.
You see, it's not just a matter of frequency, it's also a matter of timing. And phase alignment won't work when you woofers and speakers are all over the place.
Ideally, figure out what your room can do, then if you want (sub)woofers, put them under, or right next, to your main speakers. That will give you the best integration and the best sound. this will work because the best place for the subwoofers should be the same place that is best for your main L/R speakers.
This will work with ALL rooms.
It has always worked for me! Make sure the main speakers are in the best place, smoothest, best imaging, etc... then put the optional woofers next/under them and watch them both sing, in perfect time alignment.
The only time you might break that rule is:
(1) If you are using a real subwoofer and your main speakers go deep... as in using full range L/R speakers in an HT with a separate LFE channel. If the subwoofer is driving a very narrow range of low frequencies, then you are only using it for butt shaking special effects and will rarely interfere with the sound staging of the L/R speakers - arguably, in an HT, all speakers should be wide horizontal dispertion monopoles.
(2) If you use planars, dipoles or bipoles, You might have to place the woofer a couple of feet from the main speakers.
BTW, years ago, playing with two pairs of Acoustic Energy AE1s and Entec woofers, I tried stacking the monitors, tweeters in the middle, d'Appolito style, on top of the woofer. I was able to rotate the speakers to achieve direct d'Appolito configuration, bipole or dipole... it worked fantastic. The bass was in direct alignment with the front firing drivers and I could move the whole stack back and forth from the back wall to integrate the sound.
You can do this when you have worked on the room and have matched the system to the room!
And you can do this in ALL rooms.
(1) Don't put a huge system in a small room.... don't try for 20Hz in a small room with low resonant modes..
(2) Do notice that I call for using two (sub)woofers. One per speaker side. But not to smooth out the bass, since the the L/R speakers should already be in the best spots, but to extend the bass response evenly from both channels -if you main speakers require it and the room can support it.
Now a "normal" room is a bad sounding room. I guess my rooms are Ab Normal.
And then you use words such as "applies for just about all domestic rooms" which simply negates your argument. What is "just about all"? How do you measure that? 10%, 50%, 90%?
The truth is simple, work on the room: select a room that has reasonable acoustics, select an audio system that can work in that room (1) and move from there. Add acoustic traps and treatments as a last resort.
Matching the audio system to the room's capabilities should be your first and foremost concern if you want good sound (even frequency response, soundstaging, detail..).
If your room sounds bad in the bass.. then adding -willy nilly- one (or more) subwoofers is a recipe for disaster. Even with equalization you are going to end up with a very spotty, uneven frequency response. If you put one (or several) woofers around the room (2) you are going to destroy the integration between the main speakers mid bass and the subwoofers.. time alignment will be destroyed. If you use digital filters... well, you have just digitized what should be a nice and simple audio system. You've added a host of other problems.
You see, it's not just a matter of frequency, it's also a matter of timing. And phase alignment won't work when you woofers and speakers are all over the place.
Ideally, figure out what your room can do, then if you want (sub)woofers, put them under, or right next, to your main speakers. That will give you the best integration and the best sound. this will work because the best place for the subwoofers should be the same place that is best for your main L/R speakers.
This will work with ALL rooms.
It has always worked for me! Make sure the main speakers are in the best place, smoothest, best imaging, etc... then put the optional woofers next/under them and watch them both sing, in perfect time alignment.
The only time you might break that rule is:
(1) If you are using a real subwoofer and your main speakers go deep... as in using full range L/R speakers in an HT with a separate LFE channel. If the subwoofer is driving a very narrow range of low frequencies, then you are only using it for butt shaking special effects and will rarely interfere with the sound staging of the L/R speakers - arguably, in an HT, all speakers should be wide horizontal dispertion monopoles.
(2) If you use planars, dipoles or bipoles, You might have to place the woofer a couple of feet from the main speakers.
BTW, years ago, playing with two pairs of Acoustic Energy AE1s and Entec woofers, I tried stacking the monitors, tweeters in the middle, d'Appolito style, on top of the woofer. I was able to rotate the speakers to achieve direct d'Appolito configuration, bipole or dipole... it worked fantastic. The bass was in direct alignment with the front firing drivers and I could move the whole stack back and forth from the back wall to integrate the sound.
You can do this when you have worked on the room and have matched the system to the room!
And you can do this in ALL rooms.
(1) Don't put a huge system in a small room.... don't try for 20Hz in a small room with low resonant modes..
(2) Do notice that I call for using two (sub)woofers. One per speaker side. But not to smooth out the bass, since the the L/R speakers should already be in the best spots, but to extend the bass response evenly from both channels -if you main speakers require it and the room can support it.
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Many roads lead to Rome😄
I agree that aiming for deep bass towards 20hz have been the downfall for many trying to get a good sweet sounding system.
My dad insisted I bought the 15 inch speakers instead of 12s I had planned. He was tired of driving me around every time I gradually upgraded. They sounded awfull in my small room. I think there was a 10 inch in the same lineup, that would have been great.
Cheers!
I agree that aiming for deep bass towards 20hz have been the downfall for many trying to get a good sweet sounding system.
My dad insisted I bought the 15 inch speakers instead of 12s I had planned. He was tired of driving me around every time I gradually upgraded. They sounded awfull in my small room. I think there was a 10 inch in the same lineup, that would have been great.
Cheers!
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Based on this implies you were using too high an XO point and/or slope order and/or box alignment and/or wrong driver specs with the 15", so not too large a driver issue per se. 
They were Cerwin Vega AT-100 speakers. Not diy. Yeah and it was 35 years ago. I was newbie hifi geek.
Cheers!
Cheers!
Ah! My exposure to CV box speakers are from the '70s and frankly thought they all were horrible, but designed/built some horns with their prosound (original 'Loud is Beautiful if Its Clean!') woofers that for the times could pound your eyeballs flat!
Aaah.... I fondly remember my friend renting a beach house for the summer at Seabeck, WA. 'Twas 1979, maybe 1978..., I think. I have a somewhat, ahem!, cloudy recollection of the times.
His back door faced West.. the beach and the Olympic Mountains. No neighbors for a long ways.
He had a Pioneer 929 ( I think it was ), a nice turntable, tons of records, a fridge full of cold beer and a pair of BIG Cerwin Vegas.
We'd get together after work ( sunlight up there is past 10PM ) BBQ, drink beer and crank ZZ Top.
They WAS LOUD!!!
I been bad, I been good
Tacoma, Bremerton, Pouslbo
I ain't asking for much
I said, Tony, take me downtown
I'm just looking for some P*T
The judges don't know when Red's in town
He keeps well hidden underground
Everybody's acting lazy
Falling out and hangin' 'round
My woman said, "Hey Pedro
You're actin' crazy like a clown"
Nobody feels like working
Panama Red is back in town
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