Leading Edge/Percussive Bass: Subwoofer Setup: Reference Tracks etc.

Testy Troll

Well-Known Member
Dec 29, 2015
76
42
123
REF 1: The true torture test for me Dave Brubeck: Take Five - Time Out from 2:00-4:15. The attack of the bass and the drums through this section of the piece should be both lightening fast and separate. This is very very easy to get wrong. There are minute timing differences between the drums and the upright bass. Many main speakers don't do this well at all and almost all subs/mains setups make it worse.

If everything is right, the interplay between the drummer, Joe Morello and the Bassist, Eugene Wright is breathtaking. Huge Attack and momentous bass and drums!!
I had never noticed this since my system has always rendered it well.
The bass and drums are separate and one does not cover up the other.
Guess I pass......

I can see that an unbalanced system would have problems with this passage.
 

musicfirst1

VIP/Donor
Mar 8, 2015
504
309
395
Canada
www.musicfirstdistribution.ca
I had never noticed this since my system has always rendered it well.
The bass and drums are separate and one does not cover up the other.
Guess I pass......

I can see that an unbalanced system would have problems with this passage.
Congrats!! This passage continues to improve with the calibre of the bottom octave. I use it for the bass and Natalie Merchant Live-The Gulf of Araby for the tweeter. If your system does both of these well, move to the front of the class...;-)
 

audiobomber

Well-Known Member
Oct 13, 2020
243
226
115
Sudbury ON, Canada
This is an interesting read, about separating stringed bass from kick drum in a mix. Surprising how high they adjust the "attack" frequency range. This is not subwoofer territory.
 
  • Like
Reactions: Daverich4

Testy Troll

Well-Known Member
Dec 29, 2015
76
42
123
This is an interesting read, about separating stringed bass from kick drum in a mix. Surprising how high they adjust the "attack" frequency range. This is not subwoofer territory.

That was an interesting tidbit....
 

stehno

Well-Known Member
Jul 5, 2014
1,585
456
405
Salem, OR
So over the last three years, I've spent hundreds of hours trying to tune the bass response of my System. I originally started out with a pair of Rockport Cygnus and slowly added two, then four, then finally six Rel Gibraltar G1s (connected with high level inputs but no variable phase adjustments). The speakers and the subs (and the listening chairs) travelled virtually every square inch of the first 1/3 of my 13.5'x 25' listening room, every recommended subwoofer configuration, from even with the listening chairs all the way to the front wall of the listening room, in both room nulls and peaks; 2x3 stacked and 6 swarmed at the points of highest reinforcement ala the 'bass crawl about' where one puts one, (then eventually two then three subs stacked) at the center listening position and finds the dips and peaks in the listening area.
Congratulations, Kerry, on your reported advancements as you point out it's no easy feat.

These are my findings YMMV!!!:

Distributed bass arrays, at least on my Rel Gibraltars, where 6 subs are on the floor at the points of highest bass reinforcement (AKA Swarms I believe), while being the most effective way of energizing the room and extending the frequency response of the system, unless they are perfectly DSP'd (not recommended IMO) and adjusted precisely for phase (timing) response at the listening chair, do so at the expense of attack, speed and definition of percussive components on some recordings.
Not surprised in the least if this is true. Can't help but wonder what others with stacks are really hearing vs what they claim to be hearing. The complexities of a single subwoofer seem overwhelming enough and I can't imagine the potential compounding of complexities dealing with stacks of subs.

Here are my closing thoughts

The most valuable thing to spend on one's system is time.
Absolutely. This should be every enthusiast's number 1 tenet as this is an excellent way to simultaneously improve one's listening skills while realizing system improvements.

There are a million wrong ways to set up subs, and only one right way, which is probably why subs get such a bad rap.
I think I understand what you're saying. But based on my limited bass tuning experiences (whether subs or just full-range mains), I would put it another way. Maybe something like the following,

On a bass scale of 1 - 10, there exists a seemingly infinite ways to achieve an inferior mediocre me-too unmusical type of bass that ranges anywhere within say the 1 - 7.5 range of the bass scale. There is then a threshold at say 7.5 on the bass scale where the undeniable magical or superior bass switches / clicks on or leaps into action. Since thresholds are not a rest area but are intended to be crossed over, beyond the threshold there exists a seemingly significantly less than infinite ways to continue bass improvement between say 7.5 and 10 on the bass scale. IOW, crossing the threshold is really just the beginning rather than the end toward achieving truly superior bass. And no I'm not saying my bass is a 10 as I'm aware of seveval changes that should still improve bass somewhat significantly.

You have to try a lot of subs to realize you don't need a lot of subs.

At a minimum, you need two subs, they must be sealed enclosure, as port totally defeat what were trying to do here; and ideally the driver(s) should be bigger than the largest driver of the main speakers.

I have heard dozens if not hundreds of sub setups located behind the main speakers, only three of which passed the REF1 'Time Out' test, REGARDLESS OF COST. None of the setups with subs in the corner or along the front wall can do what these cuts can do.
I dunno about the surety of these things. IME, there's too much black magic involved to be dogmatic about what works and what doesn't. Not so much with full-range speakers but certainly with subwoofers.

TO MY EAR, SUBS MUST BE PLACED so the acoustic centers of the subs are in line with the Acoustic Centers of the main speakers, if they are a little ways back, and variable phase adjustments are possible, they might work, but I'm not sure. I know there are schools of thought that subs are not directional (below 100 hz or so), one only needs one to fill in the bottom etc. These do not concur with my findings despite my subs low pass filter currently set to between 24-30Hz (my preference is drifting towards 30 Hz) and the Bayz Courantes running full range (anechoic spec -3db at 27 Hz).
Have you tried setting the subs' x-overs around the 50 - 60Hz range? If not, you might be in for a little surprise. Mid-bass has a range around 40Hz on average. The implication being that there's plenty of mid-bass higher than 40Hz. IOW, a lower x-over point limits the subs to reproducing only the lower region of a mid-bass note rather than the entire bass note which IME also potentially impacts soundstage (more ambient info). I'd have to check but I think my sub's x-over is dialed in around 55-60Hz to ensure more of an entire mid-bass note is at at sub as well as mains.

I think there were literally dozens of times I was ready to sell the subs over the last three years.

However, now that I have found MY best sub locations, I'll never live without subs. Two for sure.

The extra 5-10 Hz is absolutely critical, even if your mains go down to 20hz. The easiest things to hear are, believe it or not increased soundstage width, depth and general ambience, finally followed by the extension to approximately 18Hz..

For my room, The additional two pairs of REL subs (from 2 to 6) provide only 1-3 hz extension with dramatically more complicated setup issues. My extra two pairs are now for sale.

....
As my bass has continuted to improve since crossing over the threshold, I'm more convinced than ever there exists but two great performance secrets in high-end audio and achieving a superior / musical / magical bass is one of them. When acheived, it literally seems to change most every sonic charactertistic about the playback presentation. Perhaps the best way I could put it is - the difference between mediocre and musical bass is perhaps not much different than listening to a well-engineered MP3 recording vs a well-engineered SACD recording. For me, it's easily been that dramatic. Especially when taking into consideation levels of increased enjoyment with most every recording.

Nevertheless, I'm surprised at the seemingly lack of useful information available toward the subject of superior bass even by the so-called experts. Achieving a superior or musical bass seems about as common as all the planets being perfectly aligned as I've yet to hear such bass in another's system. Yet, I'm aware of a few who seemingly achieved it. But even that's based on their words alone in forums rather than actually listening to their playback systems. Who knows what anybody is really hearing?

Because the potential impact is so great bass has been one of my favorite subjects and I wish there was an in-depth thread on improving bass with some real experts leading the way. Starting with putting all the cookies on the lower shelf so at least this kid could get at 'em because flying in the dark is vastly overrated.
 
Last edited:

musicfirst1

VIP/Donor
Mar 8, 2015
504
309
395
Canada
www.musicfirstdistribution.ca
I'm more convinced than ever there exists but two great performance secrets in high-end audio and achieving a superior / musical / magical bass is one of them. When achieved, it literally seems to change most every sonic charactertistic about the playback presentation.
Wow John, put a mark on the wall brother, for once we agree!;)

And yes, I tried setting the low pass filter on the subs up to 90hz in steps, but I perceived 'muddiness' perhaps caused by a doubling of the frequencies between the subs and the main speakers running full range (-3db@27Hz) into the 90 hz setpoint of the low pass filter on the subs.

But there were positive attributes as well, that kind of makes me want to experiment with a true outboard crossover at 70-90hz,
 

stehno

Well-Known Member
Jul 5, 2014
1,585
456
405
Salem, OR
Wow John, put a mark on the wall brother, for once we agree!;)
Let's not jump to conclusions just yet. Lemme' check my notes as I may have mistyped them. :)
 

audiobomber

Well-Known Member
Oct 13, 2020
243
226
115
Sudbury ON, Canada
This piece on Devialet’s SAM is worth a read when you’re discussing bass optimisation

Interesting idea, but severely limited. SAM only partially corrects the loudspeakers, does nothing to to address room anomalies, is not intended for subwoofer correction, and needs a Devialet amp.

Dirac software is interesting, inexpensive, does phase (timing) and FR correction, crossovers, accommodates full-range corrections and multiple subs. I may have just talked myself into trying a miniDSP SHD Studio.
 
Last edited:
  • Like
Reactions: Mark Seaton

Blackmorec

Well-Known Member
Feb 1, 2019
747
1,271
213
Interesting idea, but severely limited. SAM only partially corrects the loudspeakers, does nothing to to address room anomalies, is not intended for subwoofer correction, and needs a Devialet amp.

Dirac software is interesting, inexpensive, does phase (timing) and FR correction, crossovers, accommodates full-range corrections and multiple subs. I may have just talked myself into trying a miniDSP SHD Studio.
That’s a strangely defensive reply.
 

RBFC

WBF Founding Member
Apr 20, 2010
5,158
46
1,225
Albuquerque, NM
www.fightingconcepts.com
I've always mentioned BIS-232 Kroumata Percussion Ensemble, Track 4 "Hierophonie". Big transient energy on drum strikes at various locations around the huge soundstage. Since the recording is not extremely "dense" with instrumentation, the clarity of each percussion instrument is enhanced.

I also have experimented with subwoofer phase (JL F113s) and agree on the smearing that results from improper setup. Seeing a stack of single subs make me wonder about how proper phase integration can be accomplished.....

Lee
 

musicfirst1

VIP/Donor
Mar 8, 2015
504
309
395
Canada
www.musicfirstdistribution.ca
I've always mentioned BIS-232 Kroumata Percussion Ensemble, Track 4 "Hierophonie". Big transient energy on drum strikes at various locations around the huge soundstage. Since the recording is not extremely "dense" with instrumentation, the clarity of each percussion instrument is enhanced.

I also have experimented with subwoofer phase (JL F113s) and agree on the smearing that results from improper setup. Seeing a stack of single subs make me wonder about how proper phase integration can be accomplished.....

Lee
While I agree it is very difficult to integrate subs without variable phase/timing control. It is possible, and no more difficult with 1,2, or 2 stacks of 3 high subs. It all boils down to 'location, location, location. My six pack of Rels were no more difficult to integrate with my Rockport Cygnus than a 'stereo' pair. Problems did arise however, when more than two subs interfered with the omni radiation of the Bayz Courantes mid/tweeter.
 

oldmustang

Well-Known Member
Dec 1, 2012
1,057
3,124
1,445
While I agree it is very difficult to integrate subs without variable phase/timing control. It is possible, and no more difficult with 1,2, or 2 stacks of 3 high subs. It all boils down to 'location, location, location. My six pack of Rels were no more difficult to integrate with my Rockport Cygnus than a 'stereo' pair. Problems did arise however, when more than two subs interfered with the omni radiation of the Bayz Courantes mid/tweeter.
My experience as well. I've found no additional difficulty integrating my 2-high stacks of SVS SB16 Ultras compared to the first pair of Ultras. I don't have an omnidirectional pair of main speakers to contend with, though my Sonus Faber Aidas do have rear-mounted drivers. However, my stacks are clear of the main rear radiation pattern.

Steve Z
 

musicfirst1

VIP/Donor
Mar 8, 2015
504
309
395
Canada
www.musicfirstdistribution.ca
Yes Steve, I agree completely. And in case I didn't make it clear, the 2x3 high Rels with the Cygnus shared almost exactly the same footprint as the first pair.
 
  • Like
Reactions: oldmustang

marty

Well-Known Member
Apr 20, 2010
3,025
4,173
2,520
United States
TO MY EAR, SUBS MUST BE PLACED so the acoustic centers of the subs are in line with the Acoustic Centers of the main speakers, if they are a little ways back, and variable phase adjustments are possible, they might work, but I'm not sure. I know there are schools of thought that subs are not directional (below 100 hz or so), one only needs one to fill in the bottom etc. These do not concur with my findings despite my subs low pass filter currently set to between 24-30Hz (my preference is drifting towards 30 Hz)

I'm in large agreement with the OP, and am sympathetic to the trials and tribulations you have endured, having toiled in this space for years. A few minor comments if I may:

1) I'm not sure if it is the acoustic centers of the main and sub cabinets that must be aligned, or whether it is the voice coils of the main woofer and sub drivers that should be aligned. There are no rules here, and trial and error with some flexibility of placement is probably the best approach regardless of the presumed starting point.

2) Low frequencies (down to a point) are very directional. Anyone who has been to a symphonic concert knows this. The conventional wisdom that subs are non-directional is simply misguided in my opinion. (BTW, the use of swarms does not invalidate this. Swarms may offer a very compelling advantage in neutralizing large resonant peaks in a listening environment, but does not nullify the fact that low frequencies from natural instruments are quite directional.)

3) The use of a subwoofer phase adjustment has its place, but can NEVER overcome the error in time alignment inherent in placement when subs are located behind the mains. No less an expert than Barry Ober from JL Audio agrees with this but states that although time alignment may not be perfect, judicious set-up using a phase adjustment can still be quite beneficial and sonically pleasing. However, Barry's typical approach is to set the sub crossover point in the 60-80 Hz range whereas I am aligned with the OP that a setting <30 Hz works best for me - especially if the full range speaker (In my case Wilson Alexandrias) has adequate low end to begin with and all you are looking for is supplementation at the lowest frequencies (<~28 HZ).

4) The best low frequency test track is...wait for it...pink noise! If you don't get a good and relatively smooth frequency response with track 3 here, don't even bother with the battle cruiser tracks.

5) I have my own list of reference bass tracks and there are many of them. But when all is said in done, whenever I think I've got it right, I always do a check and balance by playing a great basso human voice such as Issac Freeman of the Fairfield Four. (Low E and C are 40Hz and 31Hz respectively, which some great bassos can hit). Nothing and I mean nothing, can tell you if your bass set-up is wrong, more than playing a well-recorded low human voice. The reason is fairly obvious. We all think we know what a tympani, upright bass, kick drum and 32Hz organ pedal etc. sounds like, but not like we know what an unamplified human voice sounds like. If a well-recorded deep baritone or basso human voice doesn't sound natural, it tells me I have more subwoofer set-up work to do.. In this context, "natural" sounding as it pertains to human voice is, to use the common analogy, like pornogrphy- you know it when you hear it.
 
Last edited:

marty

Well-Known Member
Apr 20, 2010
3,025
4,173
2,520
United States
I was PM'd and asked to reprint this which I wrote some time ago. Not sure you will find it useful, but it's free (and you know what they say about free advice)...... So with that in mind:

Subwoofer set-up and prep guide Part 1:

I hope these notes are useful. They are not a substitute for an acoustician, but I learned a lot by doing this exercise with my Alexandrias over the past year.

https://amcoustics.com/tools/amroc?l=30&w=22&h=14&ft=true&r60=0.6

If you plug in your room dimensions and look at the “bolt-area” graph, you will see an “x” out of the ideal range which is lightened from the surround. If your room is outside of that range, it means you have a set of room frequency resonances that are very unevenly distributed, and therefore difficult to correct. You can see exactly where your room resonances are as function of frequency right above the bolt area graph.

Before you begin your speaker set-up, here are the things you really need to get to make this exercise as painless as possible.

1) Granite Audio Ultimate Low-Bass test CD

http://www.graniteaudio.com/phono/page4.html

The only CD I know that let’s you identify room resonances from 20-110Hz by playing each frequency. If you want to understand your room and where the problems are, this is indispensable.

2) Get a roll of blue painter tape to mark-out speaker position.

3) Leica Disto D2

https://www.amazon.com/Leica-DISTO-...57&sr=8-1-spons&keywords=leica+disto+d2&psc=1

This marvel is a heck of a lot easier than a tape measure. Put a line of blue tape down the middle of your room to your chair. Sit in your chair, bend over and put the Leica on the line and aim it at the bottom of your speaker to record distance. This is a reference point only to make sure each speaker is the same distance from your meter. Accurate down to 1/16th inch. To get an accurate ear-speaker distance, hold it up to your ear and aim it to the cabinet somewhere near the top woofer (i.e. approx. ear height)

4) Get a Spectrum analyzer for your iphone or ipad

5) super sliders https://www.amazon.com/Furniture-Sl...&keywords=super+sliders&qid=1607990629&sr=8-9
Way easier than putting on wheels to move your speakers

6) You will need a pink noise track on a CD.

I use track 3 of this disc. It works very well.

If you’re ready to begin, the best place to start is with the main speaker placement. First, turn your subwoofers off completely. We won’t even talk about subs for quite a while. The placement of the Main speakers is the key to good sound in your room. Once you get that down, the subs are another project, but a much easier one if the mains are well placed

To be continued....
 
Last edited:
  • Like
Reactions: christoph

marty

Well-Known Member
Apr 20, 2010
3,025
4,173
2,520
United States
Sub set-up prep: Part 2

Where exactly to do place the main speakers?
A extremely useful guide as a place to start is here

http://www.cardas.com/room_setup_rectangular_room.php

I found the distance to the side walls was spot on with his recommendation. As far as distance to the back wall, I played around a bit and when you have everything on sliders, it’s really easy and a one man job.

What you need to do is just play around until you get a pink noise response at the listening position that is reasonable smooth and looks like this using the Onyx Analyzer program above

1607991505001.png


This is going to take some work. Using the Cardas starting point as a reference, the first thing you will do is calculate the distance of the listening position based on the width of the speaker. (For Wilson Alexandrias, a reasonable starting point is to place them using the recommended “ideal” Wilson triangle ratio of 1.1-1.25.. For other speakers, trial and error is probably the best way to get there, but it can take some work!.Whether you prefer to be inside the ideal equilateral triangle (often called near-field or quasi near-field) or outside the triangle is strictly personal preference and is very much speaker/room/listener preference. I've heard great systems that run the gamut as far as the triangle set-up paradigm is concerned.

Don’t worry about getting it “perfect” until you get your low frequencies to look as smooth as the graph above. There SHOULD be a small gradual peak at around 60-80Hz as this mimics the famous B&K microphone curve I have talked about for years. You are not looking for a flat frequency response here!! But what you want to do is place the speakers so you avoid large (10-20dB) peaks and valleys. THAT is the key. If you can do this, chances are you are in good shape moving forward. Once you’ve gotten this far, its fairly easy to identify individual resonances with the Granite test CD.

Then, you can go back to the amroc site, put the cursor over the exact frequency that causes the resonance, and go to the “Room 3D” graph to see exactly where the room is pressurized so you know exactly where it might be helpful to put in a ASC tube traps or other resonance reduction devices. I wish someone would have shown me this years ago. I would have me saved tons of time doing trial and error room correction.

If all goes well, it should only take you about a month to get it right. (I’m serious). It took me a year to do this but I had to stumble through this the hard way and get educated first. If someone told me what I just told you, I could have done it in a month. (The Wilsons are the hardest speakers I’ve ever set up due to their exasperating demands for exact listening height which is highly listener dependent.). Finally, when you’ve done that, you can really work on fine-tuning the sub set-up. But believe me, setting up subs without doing this work first is a complete waste of time. Changing cable and PCs at this point honestly is a fool’s errand. Plenty of time for that down the road. You really need to get the fundamentals right first. No cable or cord is going to fix a 20dB peak or trough. Just like you can’t take out a cataract and get 20/20 vision if you have a 20/100 retina, the same is true here. I used that line with an ophthalmology buddy who understood what I meant immediately!)

For the subs, I do think that getting the cabinets or voice coils in the same plane is critical, especially if you’re not using dsp. From here on out, the best way to finalize position is to listen to one channel at time with material that is not overly complex. Simple recording of piano (left hand), acoustic bass, isolated kick drum, and of course, human voice will offer a lot to make these adjustments doable. Once you think you’ve got it, hopefully you’ll find that placing both subs similarly for both channels will give you great results.
 
  • Like
Reactions: RBFC and christoph

musicfirst1

VIP/Donor
Mar 8, 2015
504
309
395
Canada
www.musicfirstdistribution.ca
Marty

I have some Fairfield Four, but the recording bites. Can you recommend something specifically by them?
 

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu

Steve Williams
Site Founder | Site Owner | Administrator
Ron Resnick
Site Co-Owner | Administrator
Julian (The Fixer)
Website Build | Marketing Managersing