Author Topic: Reference Lab Quality SAS Audio Labs 11A Line Preamplifier  (Read 2485 times)

Offline steve

  • Audiologist
  • *
  • Posts: 1238
Reference Lab Quality SAS Audio Labs 11A Line Preamplifier
« on: August 08, 2020, 08:04:27 PM »
The last used SAS Audio Labs Reference 11A that was for sale was some
5 years ago, in Europe. 

The 11A was the reference preamplifier by both Bound for Sound editor/publisher Martin DeWulf and by BFS reviewer Dr. Richard Weiner. (No magazine advertisements accepted.)

The only preamplifier on the planet that has an adjustment to compensate for different amplifier input impedances (Z) on the fly, which affects the frequency response.

Six power supply filter stages. Specialized filtering to prevent any input contamination from AC, power cords, transformers etc.

Only the highest quality parts were utilized, such as Vampire all copper jacks, Military Grade non-inductive resistors, 6N pure copper wire, gold plated tube sockets etc. Parts tolerances were less than 0.5% and between channels.

Mute section to prevent thumps with both power on and off

Series vacuum tube regulation

An AC polarity switch (mute will function when flipped, ~45 seconds)

The 11A under went 6 years of specialized, proprietary listening tests for perfect, natural, total accuracy of your music.

The owner's personal reviews.

"Dr. Rich Weiner: "The SAS 10A/11A is the most musically truthful preamp I'm aware of, and I will expand that statement by listing some of the line stages I've had in my otherwise very stable system: Herron VTSP-1, VAC CPA III, VAC Standard LE, Audio Research 3A, ARC 8, ARC 10, Mark Levinson ML-1, Levinson ML-7, Levinson ML-10A, Original Aronov PS-100 and Musical Concepts modification, Nagra PL-P, Beveridge RM-1, Rappaport, Placette Passive - there are more, but you get the point. Until I got the 10A/11A, I struggled to make the other components live up to their potential."
(Rich owns upgraded $15,000 300B monoblock amplifiers.)

"Graham: "I took the B11A into a shop in Auckland. I know the owner fairly well, and we agree that Shindo make some wonderful pieces of kit. (I wasn't looking for a change!) Almost immediately we started listening, he said "That's really fast!" We also agreed that the B11A was much clearer, making the Shindo sound slow, muddy, and coloured." 

"Bob: "Hey guys. . .if anyone's interested, I'm selling my Tram 2 preamp since my SAS B11A is so awesome...." (Tram 2 uses 45, 2A3s)



Specifications are given for those interested in such.

Notice the FR specification is not simply +/-0,1db from 20-20khz. This equates to tonal variations in the poor range of -54db.
Clearly perceived.

Frequency Response 20hz:                  < -0,015db, 25k load. (16db tighter than 0,1db spec)
Frequency Response 20khz:                 < -0,0015db at 20khz, 100pf load (36db tighter than 0,1db spec)
                                        
Gain:                                                  20db
Total Harmonic Distortion at 2 vrms:      0.015%, Approximately -78db or less (Min 18db less than with any 6SN7 or variant)
Channel Separation at 10khz:                90db typical
Signal Polarity:                                     Inverts
Input Impedance:                                 25k ohms
Output Impedance:                               1.9K (1900) ohms
Min. Amplifier Input Impedance:             25k ohms (20k ohms but with slight loss of bass)
Volume Controls:                                  2
Tape Loops, HT bypass:                         Optional
Line Inputs:                                           3 Basic Version (5 Standard version)
Preamp. Outputs:                                   2

Line Cord Length:                                  6 feet standard
Power Consumption:                              28 watts
Power Requirements:                             120/240 Volts AC, 50/60hz (set for 120 volts, 0,25 amp slo-blo)
Dimensions:                                          19" front
                                                            4" high (with stock feet)
                                                            14 1/4" deep (counting knobs and jacks)

Condition good, gold knobs are little dingy from hands.

Contact me vis PM or stevesammet at omnilec.com

Cheers

steve

« Last Edit: August 11, 2020, 10:02:56 PM by steve »
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
SAS Test Phono Stage
Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
SAS 25 W Ref Triode/UL Monoblocks
2 way Floor Standing Test Speakers

Offline Nick B

  • Audio Neurotic
  • *****
  • Posts: 4093
Re: SAS Audio Labs 11A Line Preamplifier
« Reply #1 on: August 08, 2020, 08:54:22 PM »
It’s the first one I’ve seen for sale, Steve. Have maybe seen 1 or 2 of the 10As. Good luck on the sale.
Nick
Orchard Starkrimson Ultra amp
Supratek Chardonnay preamp
JMR Voce Grande speakers
Border Patrol SEi dac
Holo Red streamer
Hapa Aero digital coax
WyWires Silver cables
TWL Digital American II p cord
Audio Envy p cords
Roon, Tidal, Qobuz
PI Audio UberBUSS

Offline steve

  • Audiologist
  • *
  • Posts: 1238
Re: SAS Audio Labs 11A Line Preamplifier
« Reply #2 on: August 09, 2020, 06:31:34 PM »
It’s the first one I’ve seen for sale, Steve. Have maybe seen 1 or 2 of the 10As. Good luck on the sale.
Nick

Thanks. I also cannot remember when the last used 11A was sold. I made an adjustment in my above post by adding
some customer/BFS reviews. 

By the way, did you notice the FR and Distortion specifications in my spec section? The fr is not simply +/-0,1db 20-20khz,
which is an absolutely worthless spec. The distortion is about a tenth less than other vacuum tube preamplifiers. The sonic difference is perceptible.

When it is gone, one won't see it again.

Cheers and great week Nick.

steve
« Last Edit: August 09, 2020, 06:59:02 PM by steve »
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
SAS Test Phono Stage
Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
SAS 25 W Ref Triode/UL Monoblocks
2 way Floor Standing Test Speakers

Offline steve

  • Audiologist
  • *
  • Posts: 1238
Re: Reference Lab Quality SAS Audio Labs 11A Line Preamplifier
« Reply #3 on: August 27, 2020, 10:41:52 AM »
Mrs. DeWulf just contacted me and has decided not to sell the 11A as it is the best of the preamplifiers
Marty kept on hand to compare against in his reviews.

Cheers

steve
« Last Edit: August 27, 2020, 10:48:05 AM by steve »
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
SAS Test Phono Stage
Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
SAS 25 W Ref Triode/UL Monoblocks
2 way Floor Standing Test Speakers

Offline Nick B

  • Audio Neurotic
  • *****
  • Posts: 4093
Re: Reference Lab Quality SAS Audio Labs 11A Line Preamplifier
« Reply #4 on: August 27, 2020, 11:41:16 AM »
Well, Steve, it is staying in a good home. It was so nice meeting Marty at a CES years ago as I was such a long time subscriber to his newsletter.

Good luck with the remaining sales.

Nick
Orchard Starkrimson Ultra amp
Supratek Chardonnay preamp
JMR Voce Grande speakers
Border Patrol SEi dac
Holo Red streamer
Hapa Aero digital coax
WyWires Silver cables
TWL Digital American II p cord
Audio Envy p cords
Roon, Tidal, Qobuz
PI Audio UberBUSS

Offline steve

  • Audiologist
  • *
  • Posts: 1238
Re: Reference Lab Quality SAS Audio Labs 11A Line Preamplifier
« Reply #5 on: August 31, 2020, 11:00:35 PM »
Thanks Nick. I know what you mean. Marty was a nice guy who loved audio to the tenth degree. He loved to tinker and repair
components when he had a chance. He will be sorely missed.

Here is a new list from Mrs. DeWulf, with prices.
« Last Edit: August 31, 2020, 11:03:56 PM by steve »
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
SAS Test Phono Stage
Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
SAS 25 W Ref Triode/UL Monoblocks
2 way Floor Standing Test Speakers