Solid State Preamp Reviews

Bryston BP-173 line preamplifier Associated Equipment

Sidebar 2: Associated Equipment

Analog Sources: Linn Sondek LP12 turntable with Lingo power supply, Linn Ittok tonearm, Spectral MC cartridge; Day-Sequerra 25th Anniversary FM Reference, McIntosh Laboratory MR-78, Sony XDR-F2HD FM/AM tuners.
Digital Sources: Bryston BCD-1 CD player & BDP-3 media player (IAD soundboard) & BDA-3 DAC; Oppo digital BPD-103 universal BD player; Lenovo P50 ThinkPad computer running Windows 10 Pro (64-bit), Bryston Windows USB driver, JRiver Media Center 23, Roon Core V.1.4 (build 300).
Preamplification: Sutherland Engineering KC Vibe phono stage & Vibe head amplifier; Bryston BP-26, Mark Levinson ML-7 (with optional phono boards),
Power Amplifiers: Constellation Audio Inspiration Stereo 1.0, Mark Levinson No.534.
Loudspeakers: Revel Ultima Salon2.
Cables: Digital: Wireworld Starlight coaxial. Interconnect: Bryston (balanced), Mark Levinson Silver, Pure Silver Cable (balanced), Red Rose Silver One, Totem Acoustic Sinew (single-ended). Speaker: Coincident Speaker Technology CST 1, Pure Silver Cable R50 (biwire double ribbon), QED X-Tube 400, Ultralink Excelsior 6N OFJC. AC: manufacturers' own.
Accessories: JL Audio CR-1 electronic crossover; Apple iPhone 6 with Studio Six iTestMic & Audio Analyzer App, v.10.7.11; Apple iPad;Torus Power RM 20 power conditioner; Salamander Designs Synergy System Twin-width S40 Rack.
Listening Room: 13' L by 11.5' W by 8' H with flat ceiling, sparsely furnished with IKEA area rug & overstuffed chair; 6' by 2.5' by 7' alcove in rear wall filled with desk and books; windows in front wall covered with closed blinds; rear of room opens to upstairs hall through 7' by 4' doorway.—Larry Greenhill

COMPANY INFO
Bryston Limited
677 Neal Driv
Peterborough, Ontario K9J 6X7
Canada
(705) 742-5325
www.bryston.com
ARTICLE CONTENTS

COMMENTS
Ortofan's picture
Submitted by Ortofan on May 24, 2018 - 5:00pm

... "superbly well engineered" and "it is difficult to see how a preamplifier could perform any better on the test bench", is it sufficient to derive the full benefit of 24-bit hi-res recordings?
A noise and distortion level of 0.001%/-100dB is barely equivalent to 16-bit resolution. Even the -120dB level only equates to about 20-bit resolution. The LSB for 24-bit encoding is on the order of a level of 0.00001%/-140dB. Does any preamp come close(r) to achieving this level of performance?

dalethorn's picture
Submitted by dalethorn on May 25, 2018 - 5:05am

Mind-boggling. So whatever the preamp is capable of with the best-case 1 khz test tone, you run a typical 24-bit recording through it and try to hear the preamp's contribution to the sound? No argument here, just trying to imagine how all that breaks down in the real world.

Gnib's picture
Submitted by Gnib on November 28, 2018 - 11:36am

I`m very curious about this follow-up on the DAC and phono modules.

dalethorn's picture
Submitted by dalethorn on November 28, 2018 - 12:52pm

"Cubed models employ an array of 12 active devices for the first 6dB of gain. Developed by the late Dr. Ioan Alexandru Salomie, this array acts as "a super-linear" input buffer to filter out audio- and radio-frequency noise, particularly anomalies that originate in the power line, reducing the overall noise and distortion to less than 0.001%."

Well, I thought Ortofan's questions were simple enough, but the array (no pun intended) of issues aren't going to make things easy. Ignoring any photo stages (can I?), the "array of 12 active devices" acting on the "power line anomalies" is interesting. I'd prefer to filter my power elsewhere, but who knows? Maybe these guys have tricks that their competitors don't.

allhifi's picture
Submitted by allhifi on December 23, 2018 - 6:21am

Cubed's IBG (Input Buffer/Gain) circuit may be advantageous in main amplifier stages but may not be particularly suitable for preamp's 'Input' stage.

Bryston's 'Cubed' series amplifier's clearly have an articulation/ resolution capability previous series lacked.

Interestingly, the "SST" series was a MAJOR improvement over ST series, but by many accounts, the SST2 was a step back?
Apparently, changes were made to the 'Input Stage' in the SST2 -not well received by many accounts. Yet it "measured" better to Bryston ! Go figure.
Come (near) full-circle, the new "3" series employs a circuit that, interestingly, has Bryston talking 'audiophile' language previously dismissed as superfluous, imaginary -not relevant/important -or "measurable" Go figure.

I suspect IBG-circuit doesn't correlate well in line-stage applications.
While many line-stage (preamp) designer's appear to be employing lower-and-lower gain 3,6, 9 db., Bryston continues with 12-18 db.? designs.

Stick with the 3B/4B3 (Cubed) amps; quite an accomplishment for Bryston.

peter jasz

allhifi's picture
Submitted by allhifi on December 23, 2018 - 5:52am

dalehorn: I suspect you are referring to Bryston's noise level/vs./source resolution ?

If so, the "breakdown" in the real-world is obvious via listening evaluations.

pj

dalethorn's picture
Submitted by dalethorn on December 23, 2018 - 8:04am

Interesting - In any case, these proprietary techniques don't reveal enough to do much besides just listening for any anomalies. If I were engineering these things, I'd like to explore ways to both shape and filter noise (if that makes sense), to try to make it less apparent psychoacoustically. How that would look from a whole-system perspective I have no idea.

allhifi's picture
Submitted by allhifi on December 23, 2018 - 9:43am

Indeed, what you say makes complete sense (re: noise attenuation)

It's unclear why makers don't consider using 'Balanced' power/ transformers in their designs -or AC Re-generation, as noted in ML's No.52 preamp.

The Balanced (Symmetrical) AC power supply I'm using (Blue Circle MR-800/1200) offers up excellent 'performance' with any/all components connected/powered. (I use on for 'sources', the other for amplification)

I have recently acquired an Exact Power SP-15 -sitting idle currently.
The SP-15 has a single, substantial 1.8-2KVa that may prove beneficial for main amplification -eventually to replace the 1200 watt Blue Circle.

The improvements in (particular lower/mid frequency) resolution is dramatic, and most welcome -when compared to wall AC power.

Yet, at busy AC-usage times of the day, one can easily hear the polluted line's impact upon SQ; a lumpy, slow sound. It happens regularly.

I suspect an AC Re-generator (PS Audio P-3) would work extremely well in low-power applications, particularly 'digital' gear where SQ improvements are incredible.

pj

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