BSG qøl Signal Completion Stage Specifications

Sidebar 1: Specifications

Description: Remote-controlled, solid-state signal processor with four analog inputs (duplicated on balanced XLR jacks and unbalanced RCA jacks). Analog outputs: 2 pairs balanced on XLRs, 2 pairs unbalanced on RCAs. Frequency response: 10Hz–50kHz, ±0.25dB. THD+noise: <0.001% (6V balanced input at 1kHz, 20Hz–20kHz). Maximum input levels: 10V balanced, 5V single-ended. Maximum output levels: 10V balanced, 5V single-ended. Input impedances: 20k ohms balanced, 10k ohms single-ended. Output impedances: 50 ohms balanced, 10 ohms single-ended. Signal/noise: >106dB, 20Hz–20kHz. Common-mode rejection ratio: >84dB. Rated power consumption: 15W (3W in idle).
Dimensions: 17" (432mm) W by 3.3" (84mm) H by 13" (330mm) D. Weight: 22 lbs (10kg).
Serial number of unit reviewed: TI21200175.
Price: $3995. Approximate number of dealers: 21; also sold direct.
Manufacturer: BSG Technologies, 3007 Washington Boulevard, Suite 225, Marina del Rey, CA 90292. Tel: (310) 827-2748. Web:

BSG Technologies
3007 Washington Boulevard, Suite 225
Marina del Rey, CA 90292
(310) 827-2748

guitarist8's picture

This certainly seems like an interesting product. However, reading through this review it reminded me of the BBE Sonic Maximizer that I have used in many live sound applications. Any experience with this, much cheaper, piece of gear in a hi-fi environment?

cgh's picture

I heard this device at RMAF11.  I could clearly hear the dB gain and a widening of the stage during the A/B session they gave us.  The people representing the company indicated they really were not into audio -  my inference was that audio was some derivative use.  As someone with a background in research level physics my BS detector normally goes off in these situations, especially when I start hearing unsubstantiated magic beanisms like "quantum" or "tunneling" or or some other high voltage torture that results in the sound being different .... I only remember them talking vaguely about phase.  My BS detector didn't go off.  They seemed genuine, excited about their product - almost giddy - curious about audiophiles, and not really too  aware of the technical details.  I was curious.  

Segue to the latest issue and I got the answer to my question.  This product, regardless of price point, will not be for everyone, especially purists (aspiring?).  But it is nice to have some transparency.  All too often some product is introduced that changes the sound; but is it for the better?  Or do people just get excited when they can hear a change and the marketing sets the stage for its reception being perceived as an improvement?  So thanks to Mr Atkinson and BSG for the transparent and well-written article.

(Edit: p.s. I have a funny picture from their room I saved that is two 'scopes comparing a signal with the device on and off.  Makes sense in retrospect :-)

OneMic's picture

I just had to comment that this is one of the best reviews I have read and frankly I am really glad to see a review of this caliber on Stereophile.   This type of educated and informing review is what myself and many of your readers have been waiting for on these type of "tweak" or enhancement products.  

JA you did a standup job cutting through the manufacture's frankly B.S. copy of "not being an effects box but digging deeper into the recording and uncovering hidden and secret information through our proprietary processing technology".   You explained in relatively understandable terms that this is precisely an effects box with a singular well known effect.  

While being an effect box is not a bad thing, I am just glad that someone at Stereophile is finally calling a spade a spade and not just ignorantly regurgitating the manufacture's fraudulent marketing speak. 

JA, I anxiously look forward to more of these kinds of articules as they do a great job of shining a light of truth on the dank and dirty world of tweaks. 

pwf2739's picture

I am not an engineer nor a designer of reference level audiophile components. I am one who very much wants to hear the reproduced music as lifelike, detailed, natural, involving and as close to live music as possible. Towards that end I have devoted a substantial sum of money to achieve what to me sounds engaging and makes me enjoy the music. 

I frankly don't really understand much of what was written in the article. I mostly skimmed through the reprint of the patent application. I certainly don't have a great sense of what a Blumlein Shuffler is, what it does, or how it may be applicable in today's high end components. I'll leave that for those far more learned than I am. 

However, I have owned a BSG qol Signal Completion Stage for eight months now. I have had professional musicians, recording engineers, audiophiles and friends in to hear my system. In each and every case, the most discussion centered around the qol unit. And each and every person who has heard it, including wives of friends were amazed at the difference it makes. 

When my friends inquired about the qol unit, we did not discuss a Blumlein Shuffler or a patent application. I simply told them that it brings much of the recorded sound to the front that may be ordinarily hidden or obscured. I told them that it made the music sound so much better. Everyone was astounded at the difference it made. Simply put, it makes the music sound more lifelike. Not in the way a graphic equalizer on a mid-fi surround sound receiver does but actually more lifelike. Your hear so much more music with qol. The proof is in the bypass button on the remote- you can actually hear what you are missing without qol. 

I don't really care if my system costs $200,000, $2,000,000 or $2.00. I can tell you that any high end system I build will have a qol Signal Completion Stage as part of the components. 

Patents, Blumlein Shufflers, equalization, this, that- all are fine discussions. For me, I'll take the music. Because qol works. 

neogeo's picture

Next time, please don't make it so obious that your comment was paid for by BSG :)

russtafarian's picture


Your article inspired me to try this out for myself.  After reading your description of the Blumlein Shuffler, I tracked down a free mid-side VST plug-in ( ), installed it in Jriver (music playback software for the PC) and played around with mid-side levels.  I found that a small increase in side level (between 0.8 and 1.2 with this plug-in) did help the soundstage bloom on many recordings.  Too much level and it sounded too phasy and exagerated.  But when set to a tasteful level, it really works!

I heard the BSG unit in a friend's system a few months ago and really liked what it did.  He listens almost exclusively to vinyl so an analog solution like the BSG is ideal for him.  For those of us who have computer audio setups, we have an alternate path to get to the same place.  Thanks for cracking this nut for us.

prerich45's picture

You are correct!!!! You do hear more instruments when cautiously applied! Biggest thing, it  was FREE!!!!  Listening to it in J River now! 

Et Quelle's picture

indecisionIs the variation on already known techs enough to justify the cost.Is it any better choosing effects on a receiver. Buy it if your wealthy, looks cool?