Thoughts on Neutralaudio X-Drei, wrt BSG QOL


Hi A'goners. This unit promises to improve the listening experience by some unexplained method in the analog domain, ie no dsp manipulation, original signal remains pure.
I have only seen one review (positive) on 6Moons, and no other references on the web.
It seems to be in the same category as the BSG QOL, which has had busy feedback here, with most listeners posting positive improvements.
Any opinions on the X-Drei, and esp. how it may compare with the QOL.
Both aren't chump change costing between $3500-$4000
spiritofmusic
Almarg, I would be interested in your opinion of the QOL's oscilloscope data as provided on the BSG website.

Others have speculated that it's a middle/side phase processor similar to devices used in mastering process.
The lack of detailed technical information on what these devices are doing makes saying anything about them very speculative, at least without hearing them (preferably on multiple systems). But fwiw:
02-15-12: Spiritofmusic
Since they work on different facets of the signal, what is your hunch as to how they might work in series ie one after the other between pre and pow? And if you feel this might be positive which sequence would you choose?
I suspect that each would have its effects independently of the other, and regardless of whether or not the other is present. Along the lines of my earlier comment, based on the available information I suspect that the effects of the X-Drei would be more system dependent than the effects of the QOL.

If both devices were present, my instinct would be to put the X-Drei first in the chain. Putting it somewhat simplistically, I envision the X-Drei as "cleaning up" the signal, and the QOL as adding something to the signal. So it would seem to make sense for the QOL to operate on as "clean" a signal as possible.
02-15-12: Onhwy61
I would be interested in your opinion of the QOL's oscilloscope data as provided on the BSG website.
I agree with your comment in the current QOL thread, which essentially says that the device is definitely introducing a significant stereo component onto the mono signal. As you may realize, the oscilloscope display is what is known as a Lissajous pattern, with one channel (left or right) driving horizontal deflection and the other channel driving vertical deflection. The QOL device clearly causes the two channels to become significantly different. Not enough information is presented to be able to say much more than that.

Regards,
-- Al
Thank you, Al. The X-DREI appears to be subtractive, whereas the QOL may be additive. As a result, I think it may process the signal less than the QOL which on another thread is possibly revealed to be a mid-side processor.
I think that if anomalies such as square waves in the ultra HF range are smoothed to correct sine waves this may reduce unnecessary load on the power amp/speakers and improve 'intelligibility'.
As a result I am tending towards the X-DREI since 2 units in series may be overkill.
So, the X-DREI merits so little discussion (your comments, Al, notwithstanding) as compared to the BSGT QOL which has had a TON of comments.
I'm a little confused as to how 2 units which claim to have such a fundamental improvement to sound quality and sit in the audio chain in the same place ie between pre and pow can have such varying interest levels from A'goners.
Both are obtuse in explaining their effects, and both have had limited reviews (X-DREI in 6moons, QOL in TAS), but X-DREI experience amongst listeners seems to be much rarer than the QOL.
A'goners, please post thoughts or this thread will go the way of the Dodo!
Marc
Blumlein laid out a lot of the fundamentals of stereo recording decades ago. He seems pretty spot-on; the closer one adheres to the basic principles, it seems, the better the sound.

I guess I still have to be convinced about the QOL.

With regards to the X-DREI, some equipment will benefit and others will not. I suspect this will have a more dramatic effect on solid state amplifiers, as RF switching is a bane of such amps, and something that could limit that might be really helpful if the amp has that sort of bandwidth to begin with. Tubes don't have switching issues so I suspect the X-DREI will have less effect on them, but its just a guess, the proof would be to give it a listen.