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24.4.150.31
...February issue #220.
It takes me a while these days to get through them.
But I thought Harley's review of BSG Technologies QOL "Signal Completion Stage" was one of the more interesting and amazing things I've read in an audio publication in some time.
The interview with QOL inventor, Barry Stephen Goldfarb, was equally fascinating.
His thought process, experiments and the way he looked at live vs reproduced sound to came up with this is a must read for every audiophile who has wondered about the differences.
The review made me want to go out and audition this unit, even though new equipment hasn't interested me in over 10 years.
Suprised no one has mentioned it.
Maybe no one reads TAS anymore...
Follow Ups:
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There is a crack in everything, that's how the light gets in.
—Leonard Cohen
...you are to be commended for your obviously hard work, time and thoroughness, not often seen in mainstream audio equipment reviews today.
Kudos.
I said empty.
There is a crack in everything, that's how the light gets in.
—Leonard Cohen
There is a thread over at diyAudio discussing the technical aspects of the QOL technology, based on reading BSG's patent applications. At first glance, the technology appears to be a narrow variation on long established inter-aural crosstalk cancellation approaches, such as Carver's old Sonic Holography, or Pollk's SDA loudspeakers.http://www.diyaudio.com/forums/analog-line-level/206970-bsg-technologies-qol-signal-completion-stage.html
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Ken Newton
Edits: 02/21/12 02/21/12
Amazing, if true (haven't had time to read the patent). As you point out, crosstalk cancellation has been around forever -- and the field has developed far beyond this primitive approach, with recursive crosstalk cancellation algorithms (not to mention that the software is free).
"ere is a thread over at diyAudio discussing the technical aspects of the QOL technology, based on reading BSG's patent applications. At first glance, the technology appears to be a narrow variation on long established inter-aural crosstalk cancellation approaches, such as Carver's old Sonic Holography, or Pollk's SDA loudspeakers."
I didn't read that thread, but I did skim the patent and would agree with the general conclusion. I also read Bob Katz' patent for K-Stereo and that seems to have much more substance. (Plus the K-Stereo product actually works, IME.)
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
I heard this demoed in s system last week.
There are a couple issues we noted:
1) when comparing using QOL in bypass mode with it engaged, the QOL is about ~2db louder engaged than with bypass making comparisons different.
2) The bypass mode is anything but transparent. You might like the QOL engaged when compared to the bypass mode but I (and others) preferred it completely out of the system since the bypass mode almost sounds like it uses a hi-pass filter.
3) the sound with QOL engaged did sound fuller and soundstage width increased. Conversely, center imaging almost disappeared. The guy demoing the QOL said that he had to toe-in his speakers a bit to compensate for the change in center imaging.
We only spent about 20 minutes playing around with it. IMHO, it does change the sound and in some ways (soundstage width, mid range fullness) it sounded better but in other ways it did not.
We had it hooked up to a scope and could see that it was changing phase from the bypass mode.
"1) when comparing using QOL in bypass mode with it engaged, the QOL is about ~2db louder engaged than with bypass making comparisons different."
If that is really true, then the designers are incompetent and/or the company are a bunch of crooks.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
The ~2db difference I noted a while back was confirmed by R. Harley in the letters section of TAS this month (he found a 1.8db difference).
You always seem to have a problem with my veracity? An entire room of ~15 people could clearly hear the volume difference that was also revealed by the Sencor scope we were using at the time. The scope, known as " Mr Tell it all" was hooked up to help identify clipping with a DIY Electrostatic speaker setup and some Dave Berning amps but we left it on for the QOL audition. We could see phase changes as well as as volume differences.
No problem with your veracity. I made my statement conditional because I don't think it right to make negative statements about products that aren't based on my first hand knowledge, which could come from hands-on experience with a product or reading the company's marketing literature. In this case, I had neither, just material posted on AA.
A product that has a bypass switch that is not level matched is deceptive. The whole point of a bypass switch is to enable A - B comparisons and these are impossible unless levels are matched. This is basic to competent audio production techniques, which depend on making correct decisions. Of course it could be that the product was somehow out of adjustment. But if I were a snake oil salesman I would engineer my products to boost the gain so that everyone could hear the magical "effect". This kind of hocus pocus is one of the things that discredits much of audio, particularly the high end "industry".
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
In defense of the QOL, the volume difference was easily to hear so it was not deceptive. If the manufacturer was trying to be sneaky they might have designed in a more subtle volume difference ( say .5db difference).
I do agree that the remote controlled "bypass" button was not terribly useful, due to the lousy sound in bypass mode as well as the volume descripency.
Nt
but it seems fairly obvious to me that we're talking about synthesis here -- that is, that they're adding something artificial. What other way is there to think about it? What's lost is detailed and system-dependent. You can't add it back unless you know what it is.
Jim
Surround and ambiance re-creation is a reasonably mature tech, around for over 40 years. Harley starts out dissing everything that has been done so far in history in digital surround to praise this novel magic box, the usual synoptic critic's stunt to make the product look like something revolutionary rather than evolutionary.
Probably just a studio item that the inventor could flog as a high price consumer item.
Low cost surround sound receivers are a "trickle down" boon for those willing to spend a bit of time to set them up. Just because Harley has never heard one set up correctly or gone to the trouble to set one up correctly does not mean that somebody just discovered the right way to do it.
I have been using surround sound to great effect for decades since the original Advent SoundSpace control, and don't need another expensive "brainstorm" to make it work.
...surround re-created with a two channel recording, beginning with my quadraphonic Kenwood receiver in 1974.
We don't know how good and convincing it is until we actually spend some time listening to it.
In all fairness, this isn't the same as what's been done before. He's flipping phase in different frequency ranges. As far as I know, it's a completely novel technique.
..
And I get a kick out of them and so appreciate the link!
How many of us didn't try the speaker at the back of the room wired across the hots? Or didn't take a listen to the Polk? speakers with the build in anti-phase mid-range. Or don't like at least some elements of the sound of bipolar speakers whether in or out of phase at the back? Ohm or MBL speakers can work well in some environments.
The killer is that each scheme usually helps when mapping some signals to some rooms (for some listeners in some locations some of the time?) but can make other one's worse. Typically they create excitement in us jaded listeners at first but that fades over time as we discover that the game is at best marginally worth the candle and don't bother setting it back up when we move or modify our systems.
Although my current listening area doesn't really support it, I'd suppose that a damped room and surround sound has the best chance of being a worthwhile complex approach. I've enjoyed this hobby for over a half-century and these schemes are always hailed as breakthroughs but seldom are around more than five years.
"Maybe no one reads TAS anymore..."
I don't. Sadly I can't since I don't want to subscribe and can no longer buy interesting issues at the now defunct Borders. First chains eat our local stores, then each other leaving us with a populace whose deepest thoughts can be expressed in 140 characters!
Regards, Rick
> > The killer is that each scheme usually helps when mapping some signals to some rooms (for some listeners in some locations some of the time?) but can make other one's worse. Typically they create excitement in us jaded listeners at first but that fades over time as we discover that the game is at best marginally worth the candle and don't bother setting it back up when we move or modify our systems. < <
I would never entertain the thought of introducing such a device in my system since it would negate the advantages I was trying to achieve based on the gear I chose.
BTW, any comparison with HDCD, or any "true" added resolution based devices - is ludicrous.
tb1
I tried that David Hafler 4 channel nonsense which kept me from throwing money away on a 4channel receiver and that shitty Who album!
...it's artificial ambience.
But stereo is artificial to begin with.
So if this product makes stereo recordings sound more like live, what's the problem?
Did you think the same about HDCD encoded recordings?
"Did you think the same about HDCD encoded recordings?"
That it is artificial ambience? That it didn't catch on?
As far as I know it was a compression/expansion scheme controlled by diddling the LSB. Unfortunately I can't comment on it's effectiveness, because while I have a few encoded CD's, I've never heard them decoded. But they sound pretty good anyway...
In that same vein, patches for early CD's, I think it was a mistake to have the preemphasis optional. Probably not a big thing now but in the early days of iffy resolution and dither the highs would have been better able to compete with those of tape and records to go along with their better bass.
Regards, Rick
...does it make the CDs sound more like live music.
If so, who cares how it works, except that the method is fascinating.
> then each other leaving us with a populace whose deepest thoughts
> can be expressed in 140 characters!
A 140 character limit is just as well for some people.
> Typically they create excitement in us jaded listeners at first
> but that fades over time
Sometimes financial constraints make life simpler. I just watch most of these breakthroughs come and go.
Bill
Don't worry, you fellers haven't missed much. There's nothing wrong with being content.
:-)
Edits: 02/11/12
It's worth reading the interview to see what he's doing, which does seem to be novel -- inverting the phase of various frequency ranges. The purist in me says ouch, and I don't have time now to read the patent now so I'm still not sure of the details. But there is research that shows that low interaural correlation in reverberation has a positive correlation with subjective sound quality both in the home and in concert halls. I've long wonder too whether the out-of-phase backwave of dipoles didn't help melt the room walls in part because the combing of the reflection occurs at the "wrong" frequencies, and the brain uses combing to help assess the size of an acoustical space. Could it be that the flips in phase confuse the psychoacoustical mechanism that tells us that we're listening in a small room? Not only is some of the delayed sound out of phase, but it's confused in phase, which would make it doubly hard for the brain to make sense of the combing cues.
.....and that thing sounded like a hammered dog turd....
Oz
Don't worry about avoiding temptation. As you grow older, it will avoid you.
- Winston Churchill
I owned one it sounded a bit hard on the old ears. My dealer University Audio Madison excepted a return and exchange.
Also very skeptical but we'll see. Scrambling the phase will likely have an obvious impact on the soundstage - but whether this is what you want long-term or just a passing fling remans to be seen. Unless it's a clear breakthrough might be best to wait for this $3,000 monster inserted into the analog chain to become a toggle switch on the computer screen.
This $900 software plugin definitely worked when I tried it during a free download period.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Did it work good enough to buy?
My conclusion was that it worked well on recordings that lacked ambiance, including one that I was transferring from analog to digital. I didn't buy it because the price was steep and most recordings don't need this processing. In this application I spent a lot of time fiddling with the settings before I got what I was hoping for. This is OK when remastering a recording for repeated playbacks by many others, but not something one would want to fiddle with every time one puts on an album.
If the price had been a few hundred bucks I probably would have sprung for it.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
And there was a thread back in October about it as well.
QOL
I am highly suspect that consistently scrambling the phase of all sources equally can *restore natural phase relationships*.
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