My monitor/subwoofer system

[JoeyGS]

Hi Al,

I have noticed in your setup that the stereo subs are located at the front wall. Any reason for this? I thought that stereo subs are placed along with the main speakers for time alignment.

Regards
Joey

 

[Al M.]

Hi Al,

I have noticed in your setup that the stereo subs are located at the front wall. Any reason for this? I thought that stereo subs are placed along with the main speakers for time alignment.

Regards
Joey

Hi Joey,

honestly, I have never understood the alleged time alignment issue, and I find it overrated. Why? I have excellent rhythm and timing, in fact I would say this is one of the highlights of my system's performance. I have also never noticed any problem compared to other systems I've heard, with or without subwoofers.

If I were to put the subs close to the speakers I would have to take them off their platforms, ASC SubTraps, in order for them not to interfere with the imaging. Now that would really be a problem. I haven't tried it with these subs, but my previous REL sub sounded horrible directly on the wood floor, with bad colorations and, well, unacceptable loss of rhythm and timing. I have no reason to assume that the story would be any different wirh the JL Audio subs.

Except maybe directly on a concrete floor, I would never run a sub without an isolating platform (perhaps a lower platform would take care of the subs from interfering with the soundfield from the main speakers, yet I don't know if any would be as good as the ASC subtrap). I have also found that the corner tube traps are crucial to flawless rhythm & timing. In my estimation, both the acoustic devices mentioned must be far more important than 'time alignment'.

Al

 

[MadFloyd]

I also feel the subs should be closer to the main speakers and that time alignment is extremely important but I understand Al's dilemma.

Sounds like a good topic for a separate thread.

 

[PeterA]

Hi Joey,

honestly, I have never understood the alleged time alignment issue, and I find it overrated. Why? I have excellent rhythm and timing, in fact I would say this is one of the highlights of my system's performance. I have also never noticed any problem compared to other systems I've heard, with or without subwoofers.

If I were to put the subs close to the speakers I would have to take them off their platforms, ASC SubTraps, in order for them not to interfere with the imaging. Now that would really be a problem. I haven't tried it with these subs, but my previous REL sub sounded horrible directly on the wood floor, with bad colorations and, well, unacceptable loss of rhythm and timing. I have no reason to assume that the story would be any different wirh the JL Audio subs.

Except maybe directly on a concrete floor, I would never run a sub without an isolating platform (perhaps a lower platform would take care of the subs from interfering with the soundfield from the main speakers, yet I don't know if any would be as good as the ASC subtrap). I have also found that the corner tube traps are crucial to flawless rhythm & timing. In my estimation, both the acoustic devices mentioned must be far more important than 'time alignment'.

Al

Al, was not your REL sub down firing and the new JL Audio subs front firing? I imagine the conditions and reaction to the ASC SubTrap would be quite different, but I don't know. Have you experimented with moving the subs around the room a bit or even placing the new subs on the floor?

 

[Al M.]

I also feel the subs should be closer to the main speakers and that time alignment is extremely important but I understand Al's dilemma.

Sounds like a good topic for a separate thread.

Ian, I take your repeated positive comments about bass and rhythm in my system as another indicator that time alignment cannot be that important.

If I am not mistaken, the JL Audio manual makes no special mention of proximity to main speakers and time alignment in its set-up instructions, where the subs are often drawn as being close to walls.

 

[JoeyGS]

HI Al,

Thanks for your reply.

I just asked because I have not tried using subs against the front wall as I presumed that the bass would be delayed in timing since I place my main speakers at 1/3 of the length of the room referenced from the front wall.

Another thing, what would be the difference in behaviour of your subs (in its current position) if it were placed nearer down the floor (also providing isolation) as compared to when it is raised as per your current setup?

regards
Joey

 

[Al M.]

Al, was not your REL sub down firing and the new JL Audio subs front firing? I imagine the conditions and reaction to the ASC SubTrap would be quite different, but I don't know. Have you experimented with moving the subs around the room a bit or even placing the new subs on the floor?

Peter, you are right about the different firing modes. But the drivers of the JL Audio subs would be close to the wood floor if the subs were directly standing on it, and undoubtedly would excite it greatly. Front firing REL subs might be a bit different since the drivers are at a distance from the floor. Yet even with the current set-up the floor is noticeably vibrating on some music, thus any proximity of a sub to it is likely problematic.

I have moved the subs out from the wall by one foot, with little difference to the sound.

 

[Al M.]

HI Al,

Thanks for your reply.

I just asked because I have not tried using subs against the front wall as I presumed that the bass would be delayed in timing since I place my main speakers at 1/3 of the length of the room referenced from the front wall.

Another thing, what would be the difference in behaviour of your subs (in its current position) if it were placed nearer down the floor (also providing isolation) as compared to when it is raised as per your current setup?

regards
Joey

You're welcome, Joey. As for your new question, I have addressed it in my latest post prior to this one (we cross-posted).

 

[JoeyGS]

Yes .... I now realize why you had to raise the subs. Thanks

 

[heebrog]

Hi Guys,

I came across this interesting article about subwoofer setup during my research that speaks about this issue of time alignment which I think you may find interesting.

It is actually from the JL audio "help center"

https://jlaudio.zendesk.com/hc/en-us/articles/205061040-Adding-a-Home-Audio-Subwoofer

Placing the subs against the back wall will help reinforce the bass so you may not need to turn up the volume as much.
With stereo subs this is less of an issue because of increased output but I think anything that stretches the amps/drivers least is probably best.
As for time alignment, the article states that due to delays in processing etc. the subs really need to be placed closer to the listener than the main speakers unless an electronic xover is used.
There are of course issues with transparency when running the mains through an electronic xover no matter how good it is (IC cables/Power cords etc. etc.)
What you may gain by having the main speakers doing less bass might be taken away by more electronic hash in the mids/highs passing through a high pass xover.
I think monitor type speakers may benefit the most as the midrange/midbass driver is often "asked" to do a low bass and well as the critical midrange.

Geoff

I also feel the subs should be closer to the main speakers and that time alignment is extremely important but I understand Al's dilemma.

Sounds like a good topic for a separate thread.

 

[Al M.]

Very interesting article indeed and thanks for your useful summary of it, Geoff. I am wondering why JL Audio hardly mentions any of this in their subwoofer manual. They do say there:

"We recommend that you begin by placing your Fathom v2 in the front of the room, near the front left or right speaker."

So far so good, but as far as I can tell that is the only thing they say or rather, allude to, about time alignment (and their diagrams in the manual for multiple subs contradict this). Yet then they continue:

"Placing it directly in the front corner of the room will produce the maximum number of peaks and the minimum number of dips in the frequency response. This can be advantageous because the Fathom v2's D.A.R.O. system can correct the resulting peaks very effectively, whereas dips in the response cannot be corrected via equalization. Dips in response can only be minimized via careful subwoofer and listener placement."

So what if the speakers are not directly at the front wall?

In any case, the article makes an overall convincing and spirited argument (in some cases a somewhat too spirited and pretty dogmatic one, I would say). Yet while the argument seems sound, this is not what I hear in my system. Sure, my bass is not perfect. For example, depending on the recording, the system does not portray the foundational low strings of an orchestra as well as some very high quality full range speakers -- but it's no slouch either in that department. Yet on a lot of other music the bass is great.

Contradictions with the audible result in my system:

1. The article says that without proper time alignment the image of a cello loses focus. Yet in my system the image of a cello is well defined, and I have witnesses for that. There is nothing diffuse about my soundstage, be it from instruments that have little bass, or instruments that are bass heavy.
2. My system can portray some of the most accurate and well-timed bass that I have heard. I do not seem to be the only one with that opinion. For example, on the first page of this thread, Alan, who is a drummer himself, raves about diverse drum tracks that he heard (Rihm Tutuguri, last mvmt., with heavy bass drums, and Art Blakey, Freedom Rider; about the latter he says this is the best he's ever heard it). Others have raved about these tracks on my system too. And people have also commented positively on the timing on rock and jazz tracks, which include bass guitar or stand-up bass.

So where does this leave me? Perhaps, despite all of that, I haven't yet heard what the system really is capable of in bass performance. I can move the subs in front of the speakers, but then I may get all kinds of problems from reflections (timbre, soundstage), since they will still be raised by the ASC SubTraps. I may try it anyway since the speakers are toed in quite dramatically, which should ameliorate reflections. Interestingly, the article mentions the benefits of elevated vertical placement of the subwoofer, up to quite high, and also the refers to the subwoofer stand by Acoustic Sciences (the ASC SubTrap).

 

[Al M.]

As for time alignment, the article states that due to delays in processing etc. the subs really need to be placed closer to the listener than the main speakers unless an electronic xover is used.
There are of course issues with transparency when running the mains through an electronic xover no matter how good it is (IC cables/Power cords etc. etc.)
What you may gain by having the main speakers doing less bass might be taken away by more electronic hash in the mids/highs passing through a high pass xover.
I think monitor type speakers may benefit the most as the midrange/midbass driver is often "asked" to do a low bass and well as the critical midrange.

Geoff

I have thought about the JL Audio CR-1 crossover. Yes, for a monitor system like mine the relief of strain on the mid-woofer might be a considerable advantage, especially on orchestral music. Yet in the past I have tried to avoid crossovers as much as possible, and the only reason I took the REL plunge in 2000 was that this was one of the first subs at the time not running a crossover from the mains, but simply running in parallel to them. As you suggest, an extra crossover may introduce loss of transparency and impurities in the signal, and I also think, it has the danger of making the main speakers lose some vividness -- the very last thing I want from my system. That happened with my previous Ensemble Reference monitors when they were coupled, via crossover, to the matching Ensemble Profundo subwoofer stands (that was back in the early 90s, I trust that the CR-1 crossover is better). In the context, there is a reason the Reference 3A speakers have no internal crossover.

I would have to test a CR-1 crossover very carefully. If a gain in orchestral music and even more slam on drums (due to better time alignment) was offset by even the slightest loss of nuance in high resolution performance and vividness on string quartets, it would be a no for me. I find string quartet performance extremely important, and I never thought the performance that I hear now, after the latest acoustic adjustments, was even possible from a system. Frankly, I am over the moon. Every system has its compromises, but a loss here would be unacceptable for me. I'd rather keep compromising on other aspects of system performance and not include the crossover.

 

[heebrog]

I agree. I also run crossover-less and don’t think the potential gains outweigh the negatives.

 

[Al M.]

Hi Al,

I have noticed in your setup that the stereo subs are located at the front wall. Any reason for this? I thought that stereo subs are placed along with the main speakers for time alignment.

Regards
Joey

Hi Guys,

I came across this interesting article about subwoofer setup during my research that speaks about this issue of time alignment which I think you may find interesting.

It is actually from the JL audio "help center"

https://jlaudio.zendesk.com/hc/en-us/articles/205061040-Adding-a-Home-Audio-Subwoofer

[...]

As for time alignment, the article states that due to delays in processing etc. the subs really need to be placed closer to the listener than the main speakers unless an electronic xover is used.

A few days ago two audiophiles visited who hadn't heard the system yet. While they did not like everything equally, they were very impressed with the Rihm piece for six percussionists and choir, and the clear and precise impact of the large bass drums which was physically felt. They also liked the 1979 live recording in Cuba of the Trio of Doom (jazz rock supergroup consisting of John McLaughlin, Jaco Pastorius and Tony Williams). They loved the rhythmic drive of the system on this recording, and also in general. Given the above discussion about time alignment and positioning of subwoofers, I asked them both specifically if they heard ANY lag of the bass, and the answer from both was "no" (one of them added, with perhaps the exception of one or two instances, but that still makes it a general no). As I thought it would be; I still can't hear any lag either.

I plan to still try the experiment with changing subwoofer positioning at some point, but it is not the highest priority. Because of the weight (100 lbs.) and size of the subs it needs two people.

 

[Al M.]

My review, and ensuing discussion:

Review: Reference 3A Reflector monitors

 

[Al M.]

Lately, and particularly the last few days, even though overall I still found the sound exciting and involving, I again heard a 'grating' hardness on peaks that I had not quite heard before the last three months, after the rug change. I thought maybe it's changing acoustics due to weather changes, and I already had ordered last week from ASC new ceiling diffusers which surely should help. But something just didn't sound right. Then I remembered to do something that I hadn't done in almost two years, but had been too lazy to do. I also thought perhaps it's less necessary because the equipment is rather new.

It was treatment with Deoxit Gold G5. So last Saturday I shut the system down and did the treatment (the Yggdrasil DAC was down for only 10 min. and did not cool down much, so it may have recovered just a day later faster than the usual 2 days from cold). I couldn't believe the amount of gray filth that came off those connections, even from 'new' equipment. I also treated the pins of the driver tubes of the amp. One day later I put it all back together, and voila, much cleaner sound. Lots of the grating hard 'sandpaper' sound on peaks is gone, and it sounds so much cleaner; those peaks sound more resolved too. Some say that if something sounds too loud compared to what you read on the SPL meter, it's a sign that it's distorted (I agree to a point, it can also have other reasons). After the cleaning some peaks sound a bit softer in volume at the same SPL reading, so perhaps a sign of less distortion. The sound seems just more effortless too.

 

[MadFloyd]

I visited Al on Tuesday to listen to his system. On the Saturday before he used deoxit.

I first wanted to listen to some tracks on CD that I brought with me. These were older recordings (e.g. Nat King Cole, Midnight Blues by Kenny Burrell, Beethoven cello sonatos with Pierre Fournier).

I immediately identified some graininess in the treble (or so I thought) . The strings on Nat King Cole sounded nice and open but much more 'vintage' than what I heard at home. The system seemed seemed to exasperate vocal sibilance. Otherwise the body seemed very good and the bass was punchy and articulate.

The Fournier cell sounded tizzy and the piano sounded like an old recording with what I refer to as 'tube tinkle' on the higher notes (not sure if you know what I mean but you've probably all heard it - imagine the high frequencies bounding around inside a tiny glass enclosure...). We didn't listen to this one very long because frankly there was no reason to. It wasn't that enjoyable.

The Kenny Burrell sounded excellent. This is a Blue Note recording that has thick punchy bass that will just ruin the playback performance on the wrong system and even in the best of systems will just be tolerable. There is some percussion, guitar (obviously) and sax. The guitar is very well recorded. It's electric and the amp sounds wonderful and it came through exquisitely on Al's system. Lots of body, incredible micro-detail (I could hear his left hand fingers lifting off the strings as he prepared to move to another part of the neck) and the dynamics were superb. The sax also sounded great.

The sound was so well balanced that we could clearly hear high hats that sounded like the proper blend of metal & brass and there was good depth to the recording.

I don't recall the exact order of what we heard - and it doesn't matter, but we listened to Anat Cohen's Happy Song CD. This was revelatory. It's a tentet so there is LOTS going on. From Anat's clarinet to various brass instruments (including barritone sax, flugelhorn, trombone), accordion, cello. The music varies from Ellington/Armstrong type jazz to Brazilian and it is so well recorded that it really did a good job of making you feel that you were watching the band live. Every instrument had remarkable tone and presence and nothing sounded the least bit compressed or digital. I know I have played this CD - at least casually but had no idea what delights were here. Unless you really don't like happy jazz played by excellent musicians, I would venture to say that this is a must own recording. It certainly is for Al (again, in my opinion).

We spent a long time listening to string quartets. I've always felt Al's system did a great job here, albeit with a few flaws. The pros are strong presence, holographic imaging and lots of midrange detail. The flaws being that the timbre was never quite correct - it was on the dark side and emphasized the bowing (e..g scratching) over string vibration (e..g the 'singing'). This time, however, everything seemed spot on. There was no muddiness in the bass, the midrange was glorious, the higher frequencies were present and not fatiguing and of course the imaging was doing its usual thing.

What was also interesting was how much Al's system revealed the differences between recordings (we listened to Shostakovich's 8th quartet by different artists).

I normally play vinyl. But I'm slowly appreciating string quartets more and more and for me to sit down and just LISTEN (e.g. not reading stuff on my iPad at the same time) I need the tone, detail and instrument separation to be very strong. There is so much more well recorded string quartet music available on digital vs vinyl so having a good sounding digital rig is a nice bonus although still not my high priority.

It just might be a bit higher of a priority now after hearing Al's system and not hearing anything remotely 'digital' about it (other than the pure black background and lack of surface noise).

Kudos and curses, Al.

 

[Al M.]

Thank you, Ian, for your report. I am glad you enjoyed the system!

Yes, the piano on the Beethoven cello sonatas with Fournier sounded as you very aptly described, not enjoyable. The piano on the more modern Beethoven Diabelli with Brendel that we played was much better. The second track in Nat King Cole had much more vocal sibilance than the first one, so this may have been a function of this particular recording/mastering. The bass on the Kenny Burrell is indeed overpowering; it helped that I could adjust with simply turning my subs down, and then it sounded quite fine, and punchy as you say. Turning down the subs also helped on the indeed excellent sounding Anat Cohen band of ten musicians. I am getting that CD and the Kenny Burrell from Amazon today. I was as smitten with the guitar sound on the Burrell as you were. Great to hear all this new music, thanks for introducing me to it!

 

[ack]

Al, congrats. Can you post the CD?

 

[Al M.]

Thanks, Tasos.

Anat Cohen Tentet:

https://www.amazon.com/gp/product/B075J3569Q/

Kenny Burrell:

https://www.amazon.com/gp/product/B00000I41G/