Anyone HEARD the qol 'signal completion' device?

03-30-12: Psag
My question is directed to those who claim to have some idea what the QOL is doing: Is it something that could be done during the recording and mastering process? If so, then it would seem to qualify as a distortion device; i.e., something that changes what was originally intended.

03-31-12: Larryakay
It is neither a distortion device nor a processor. It's "revealer" of information that has been stuck inside all signals. That information is natural and part of every live sound we hear. It's the distortion BY OMISSION in all other equipment that is the problem qol solves.

I suppose it depends on how you define 'distortion.' If 'distortion' is any alteration to the musical information of the RECORDING, then QOL certainly seems like it introduces distortion, though it may very well be pleasing distortion.

If 'distortion' is any alteration to the musical information of the EVENT the recording represents, then an argument can be made that QOL does not introduce distortion, but rather corrects it, the rationale being something like... Although QOL "distorts" the signal, the signal itself is a distortion. QOL alters the musical information of the RECORDING so that it more closely resembles the musical information of the EVENT. In other words, QOL distorts distortion, making it sound less, uhm, distorted. Whether or not distortion that corrects distortion should itself be considered distortion is a philosophical question I will leave the reader to ponder at his leisure.

In all seriousness, the idea of correcting distortion with distortion is, IMO, perfectly valid, at least as an abstraction. A good analogy would be the anamorphic film format, in which the image distortion on the film negative introduced by the camera lens during capture is "corrected" by the image distortion of the projector lens during playback. Without the anamorphic lens on the projector, you wouldn't want to watch the movie. QOL is like the projector lens, at least according to the manufacturer. I haven't heard it. Which brings me to...

Larry - I've read the information on your website, and on 2/27 I posted some comments on this thread in which I said that QOL seemed a little like Trifield, though of course Trifield is 3 channel and typically implemented digitally, whereas QOL is 2 channel and implemented analog. What QOL and Trifield seem to have in common is (1) the manipulation of the perception of width, by deriving the difference between the L/R channels and amplifying it, and (2) the manipulation of the perception of depth, by adding some kind of frequency specific phase delay. Of course my comments about the methods by which QOL manipulates the perception of width and depth are purely speculative.

I understand that QOL may involve some proprietary technologies, but I'd be very interested to hear anything you are willing to share about HOW it manipulates the perception of width and depth. If you are reluctant to share the specifics of implementation, perhaps you would be willing to share the generalities of design, beyond the metaphors already discussed.

Bryon

P.S. Whether QOL's soundstage manipulation should be considered a form of 'processing' is, I submit, a philosophical question with the same chance of being answered as the question of whether distortion that corrects distortion is itself distortion.

I’ve just read through this thread with considerable interest. I have not heard the QOL, but from what I can tell from this thread and from the information on the BSG website, QOL is designed to accomplish something very similar to Trifield, the signal processing developed by Geoffrey Barton and Michael Gerzon.

Although Trifield involves three channels rather than two, both Trifield and QOL manipulate the perception of the soundstage in two fundamentally similar ways...

1. WIDTH. The manipulation of “Width” expands the soundstage on the x axis. Trifield manipulates the perception of Width by calculating the sum and the difference of the L and R inputs, then amplifying one or the other. You can see a schematic of a typical Trifield circuit here. The Width parameter in the Trifield circuit is similar to the Mid/Side parameter described in the article that Onhwy61 mentioned, which says…

The M/S approach essentially considers it as being comprised of central and side elements. The Mid signal is the mono sum of both left and right, and basically describes those elements present in both channels. The Side signal is the difference between the two channels, and describes those elements that contribute to the stereo width… It follows from this that the balance between the Mid and Side signals determines stereo width.

Even though Trifield involves a third channel, the same basic principle determines the perception of Width.

2. DEPTH. The manipulation of “Depth” expands the soundstage on the z axis. Trifield manipulates the perception of “Depth” by adding group delay to one or more channels. Again, Trifield employs three channels whereas QOL employs two, but a similar principle seems to be involved.

Together, the manipulation of Width and Depth can create a very spacious soundstage, far more spacious than the speakers and the room would seem to permit. I know this from personal experience, as I have listened to Trifield extensively on my Meridian G68. In fact, I’ve been listening almost exclusively to Trifield for the past few months.

Meridian’s implementation of Trifield allows the user to set the values of Width and Depth, so he can tailor the soundstage to his particular room and taste. For my own taste, a small amount Width and Depth manipulation yields the best results.

The BSG website doesn’t reveal a lot of design details, except in a very abstract way. In his interview with RH, QOL's inventor Barry Stephen Goldfarb says this...

Essentially the idea was to get out of a single signal both the in-phase information and the out-of-phase information… I began to try to figure out a way of tricking the signal so that part of it would play and another part might be cancelled. I then tried layering different frequency paths. Let’s say I took a limited frequency band up to, say, 3kHz. I’d let that play. Then I would take another band-limited signal from 3kHz to 6kHz and put it in the opposite phase. Now they’re playing together. They’re not interfering because the two are not really playing the same frequency simultaneously, If you keep doing that with other frequency bands, it’s like weaving frequencies. A group of frequencies will be in-phase to a limited bandwidth; another group of a different bandwidth will be out-of-phase; and I would add these layers until the entire audio bandwidth from 20Hz to 20kHz was covered. That technique produces a whole audio signal… We call it in our patent “Phase Layering.”

The band-limited manipulation of phase is also found in Meridian's Trifield. Meridian's implementation of Trifield is digital, whereas QOL is analog, but again a similar principle seems to be involved.

None of these comments are intended to diminish the value of QOL. My own personal experiences with Trifield have led me to conclude that soundstage manipulation, when executed well, can yield very pleasing results. Judging from the owners who have contributed to this thread, it sounds like QOL’s execution is excellent.

I agree with the observation that the desirability of soundstage manipulation is, to a significant extent, recording specific. It is for that reason that, IMO, a little goes a long way.

Bryon

04-01-12: Pipedream
Not for anything but why does this matter ? Whatever it is doing or not doing is moot to me...
Just do not see the need to now how it does what it does. Really guys without a home demo all is moot. How can we put down something not heard in ones system ?

My post was motivated by nothing more than curiosity. I am not putting QOL down. If you read my comments on this thread on 2/27, you will see that I own a Meridian preamp that, like QOL, can manipulate the soundstage. As I mentioned in those comments, I enjoy the effect. So although I haven't heard QOL, I am favorably disposed to the idea. That puts me in the camp of likely supporters, not detractors.

As for my motives for asking, I happen to be an audiophile who enjoys knowing how things work, within the limits of my technical competence. For you, knowing how something works may be "moot," to use your word. I would invite you to consider that what is moot to you may be of interest to others.

Also, it's strange to me that you would challenge a person who asks a manufacturer who has already elected to participate in a conversation to talk about his product in a substantive way. Even if my comments were intended to be challenging - which they were not - it is perfectly within the limits of civil discourse to ask a manufacturer for the principles of his design and even the details of his implementation. The manufacturer is free to share as much or as little as he likes. Several well regarded manufacturers are very willing to share, and do so regularly, like Ralph Karsten of Atma-Sphere, Bobby Palkovic of Merlin, Steve Nugent of Empirical Audio, and Duke LeJeune of AudioKinesis. And since I'm already stating the obvious, let me also say...

Audiogon is a place for the free exchange of ideas and information. That's what I asked Larry for. Ideas and information.

Bryon

Thank you, Pipedream, for you post. I am in agreement with you that sound quality and listener enjoyment are far more important considerations than principles of design or details of implementation. My interest in design and implementation is a result both of my desire to increase listener enjoyment and my interest in technology, both audio technology and technology more generally. That seems to be a fairly common motivation among A'gon participants.

Having said that, I will acknowledge that, in spite of the wide range of reasons why people post about various products, they can be grouped into two broad types: those who habitually post about products they like and those who habitually post about products they don't like. The first group is usually looking for ideas and information. The second group is usually looking for trouble.

IMO.

Bryon

A couple years ago, when I made the transition from lurking to participating, I had no idea how rewarding it would be. It's been great fun to share my experiences and hear about other people's experiences. I've learned a great deal from other participants, and I've met some very kind people along the way.

So welcome to Audiogon!

Bryon