Threshold Amplifier - Overview and Schematic Collection of all Models

A friend of me will start a collection of all exist Threshold models - at least of all exist power amplifiers.
This brings me to the idea, to start this thread with an information collection with a listing of (first only all me known) models and miscelaneous parts/PCB's.

please help me to complete this list - there are probably missing a few models, especially the universal PCB names of various modules and special/custom made parts used in various amp models (eg front-end, VU-Meter PCB).Thank you therefore.
In the next time I will also redrawn those circuit diagrams, where the original schematic documents are difficult to read.

Most listed models I have found about
Threshold-Audio.com

First Series:
800A 200 Watt/Channel STASIS Stereo Power Amplifier (1975-77)
800S ???? unknown
400A 100 Watt/Channel STASIS Stereo Power Amplifier (1976-79)
4000 200 Watt/Channel STASIS Stereo Power Amplifier (1977-79, successor 400A)
800A Schematic
Threshold 800A and 800S
Threshold 800A Help!
http://www.diyaudio.com/forums/pass...els-mospec-2n5876-2n5878-mj21193-mj21194.html
Threshold 800A assistance
400A or Stasis 3?
Threshold 400 a
Threshold 400 A
Buying a 400A
http://www.diyaudio.com/forums/pass-labs/131030-would-work-400a.html
Threshold 400A HELP !!
Threshold 4000
Threshold! (4000 vs 800A)
Threshold (4000 400A CAS1)
Elettronica audio - (a cura di Piercarlo Boletti): QUAD 405 - 2 - Seconda parte (800A - high resolution schema, scroll down)
http://www.diyaudio.com/forums/pass-labs/55055-threshold-400a-parts-substitution-mods.html
Threshold 400A Power supply help
AudiogoN Reviews: Threshold 400a Amplifier (photo)

Cascode Amplifier (CAS) Series (Emitter Cascode Follower as Power Buffer)
CAS-1 75 Watt/Channel STASIS Stereo Power Amplifier (1979-81)
CAS-2 125 Watt/Channel STASIS Stereo Power Amplifier (1979-81)
THRESHOLD CAS-2 poweramp.
Threshold CAS 1
Threshold (4000 400A CAS1)

Stasis-Series:
STASIS-1 200 Watt STASIS MonoBlock Power Amplifier (1979-81)
STASIS-2 200 Watt/Channel STASIS Stereo Power Amplifier (1979-81)
STASIS-3 125 Watt/Channel STASIS Stereo Power Amplifier (1979-81)
SA-1 160 Watt STASIS MonoBlock Power Amplifier (1984-88)
SA-2 100 Watt STASIS MonoBlock Power Amplifier (1984-88)
SA-3 50 Watt/Channel STASIS Stereo Power Amplifier (1984-88)
S/150 (two series) 75 Watt/Channel STASIS Stereo Power Amplifier (1982-84)
S/200 (two series) 100 Watt/Channel STASIS Stereo Power Amplifier (1984-86)
S/300 (two series) 150 Watt/Channel STASIS Stereo Power Amplifier (1983-88)
S/500 (two series) 250 Watt/Channel STASIS Stereo Power Amplifier (1983-88)
S/1000 (two series) 500 Watt STASIS MonoBlock Power Amplifier (1984-88)
SA/3.9e 60 Watt/Channel STASIS Stereo Power Amplifier (1990-94)
SA/4e 100 Watt/Channel STASIS Stereo Power Amplifier (1989-95)
SA/6e 125 Watt STASIS MonoBlock Power Amplifier (1990-94)
SA/10e 175 Watt STASIS MonoBlock Power Amplifier (1990-94)
SA/12e 250 Watt STASIS MonoBlock Power Amplifier (1989-95)
stasis 2 and 3 schematics
http://www.diyaudio.com/forums/pass-labs/64795-stasis-2-problem.html
http://www.diyaudio.com/forums/pass-labs/92677-stasis-one-meter.html
Threshold Stasis 2.
Threshold Stasis 2.
threshold stasis 2
Threshold Stasis Model 3
http://www.diyaudio.com/forums/pass-labs/92618-another-threshold-stasis-2-rebuild.html
http://www.diyaudio.com/forums/pass-labs/34288-threshold-stasis-3-too.html
Stasis 3 Power Transistors
http://www.diyaudio.com/forums/pass-labs/112339-threshold-s-200-a.html
http://www.diyaudio.com/forums/pass-labs/158093-threshold-sa-sa-e-series-monoblocks.html
Stereophile: Threshold SA-1 monoblock power amplifier (SA-1)
Schematic and help with Threshold SA/4 (post #34: Instruction for bias adjust)

Threshold's New-Owner Series:
T 50 50 Watt/Channel Stereo Power Amplifier (1994-98)
T 100 60 Watt/Channel Stereo Power Amplifier (1994-98)
T 200 100 Watt/Channel Stereo Power Amplifier (1994-98)
T 400 150 Watt/Channel Stereo Power Amplifier (1994-98)
T 800 and T 800D 200 Watt/Channel Stereo Power Amplifier (1996-98)
TA-300 150 Watt/Channel Stereo Power Amplifier (1993)
S/160 80 Watt/Channel STASIS Stereo Power Amplifier (1992-94)
S/250 125 Watt/Channel STASIS Stereo Power Amplifier (1992-94)
S/350e 150 Watt/Channel STASIS Stereo Power Amplifier (1990-94)
S/450e 200 Watt/Channel STASIS Stereo Power Amplifier (1990-94)
S/550e 250 Watt/Channel STASIS Stereo Power Amplifier (1990-94)
S/1600 750 Watt STASIS MonoBlock Power Amplifier (1989-1994)
Threshold SA/2 SA/3 Soderburg site?
http://www.diyaudio.com/forums/pass-labs/144136-biasproblems-threshold-sa-1-a.html
http://www.diyaudio.com/forums/pass-labs/146232-schematics-threshold-series-i-ii.html
http://www.diyaudio.com/forums/pass-labs/142576-threshold-s-1000-series-ii.html
http://www.diyaudio.com/forums/pass-labs/140152-help-schematic-threshold-s-1000-series-ii.html
http://www.diyaudio.com/forums/pass-labs/136361-threshold-sa-50-a.html#post1953481
diyAudio

Unknown models:
500 ???
500/II ???
Threshold 500II
maybe SA-500 and Stasis 500 MK-II ??

not mentioned power amplifier models
about Threshold-Audio.com
but mentioned about http://www.audiopathways.com/Threshold.htm
preamp Stasis R 3.0 and 5.0
integrated Amp: Dragon V
5ch Power Amp: S-3500-E
Stereo Power Amp: Stasis 7.0 - Stasis 8.0 - S-5000-E
MonoBlock S-7000-E

Upgrade Kits:
???? ........................please let me know more, whether there are such kits or not.

PCBs and special parts for various models:

various protection unit's: PCB part No 254-6000
Front end modules (FE-89, FE90), Universal FEB, Universal Error Correction PCB
Universal LED Driver PCB for VU Light Band Displays (multi element bar graph array) e. g.
Electronics-Lab.com Blog VU meter
PCB for VU Light Band LED Display (multi element bar graph array)
VU Light Band VFD (Vakuum Fluoreszenz)-PCB
Analogue VU Moving Coil Panel Peak Indicator Meter
....................please let me know all the existing things - I have only found that from the attachement

Stereo Line + RIAA Preamplifier
NS-10 Stereo Preamplifier (1977-79)
http://www.diyaudio.com/forums/pass-labs/26003-threshold-ns-10-m1-info-wanted.html
http://www.diyaudio.com/forums/pass-labs/76557-threshold-ns10-lineamp-pcb-21.html?postid=1634684
SL-10 Stereo Preamplifier (1979-81)
Threshold sl-10?
threshold sl10
http://www.diyaudio.com/forums/pass-labs/151645-threshold-sl-10-a.html#post1937332
FET-1 (two series) Stereo Preamplifier (1981-85)
Threshold FET1
FET-2 (two series) Stereo Preamplifier (1981-85)
FET-9 Stereo Preamplifier with Phone Stage (1986-89)
FET-10Pc Stereo Phone Gain Stage (1986-89)
FET-10HL Stereo High Level Preamplifier (1986-89)
FET-9e Stereo Preamplifier with Phone Stage (1990-94)
FET-10Pe Stereo Phone Gain Stage (1990-98)
FET-10He Stereo High Level Preamplifier (1990-94)
http://www.diyaudio.com/forums/pass-labs/113706-threshold-fet-10-he-service-manual.html
Threshold Fet 10/hl Opinion ?
Threshold fet ten/pc schematics
T 2 Remote Control Stereo Preamplifier (1994-98)
T 3/T 3i Remote Control Stereo Preamplifier (1994-98)

crossover/DAC
PCX (-X10) Stereo Electronic Crossover (1987-89)
DAC1e Digital to Analog Convertor (1992-96)
DAC2 Digital to Analog Convertor (1995-98)

various URL's concerning Threshold devices:
Threshold Lovers - Threshold - Product line history
archiveamps
Stammtisch für HiFi- und Musik-Freunde | PASS LABS | Threshold
By Threshold history site not mentioned models: e.g. Stasis R-3.0 - Stasis R-5.0 - T Zero
Threshold Audo from AudioPathic
 

Attachments

  • ZZZ-Threshold univ. gain modul.pdf
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  • ZZZ-Threshold E-Line Output Stage.pdf
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  • ZZZ-Threshold univ. FEB.pdf
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  • ZZZ-Thresholdpeakdisplay.pdf
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  • ZZZ-Threshold_fe89.jpg
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  • ZZZ-Threshold universal peak display.pdf
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Attachments

  • Threshold 800A 1975.pdf
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  • Threshold 800A front left.jpg
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  • Threshold 800A front right.jpg
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  • Threshold 800A rear left.jpg
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  • Threshold 800A power meter.jpg
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  • Threshold 800A no adv. about PCB version.jpg
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  • Threshold 800A rear.jpg
    Threshold 800A rear.jpg
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  • Threshold 800A rear+front.jpg
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Attachments

  • Threshold 400A -1.jpg
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  • Threshold 400A high res..JPG
    Threshold 400A high res..JPG
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  • Threshold 400A no adv. about PCB version.pdf
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  • Threshold 400A PC-400A 11-77 14B-5400.pdf
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  • Threshold 400A-800A-4000 adjust3.pdf
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  • Threshold 400A-800A-4000 adjust2.pdf
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  • Threshold 400A-800A-4000 adjust1.pdf
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  • Threshold 400A-800A-4000 adjust4.pdf
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  • Threshold 400A-800A-4000 adjust5.pdf
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  • Threshold 400A-800A-4000-CAS1-3-stasis 1-3 adjust6.pdf
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Attachments

  • Threshold 4000 top view.jpg
    Threshold 4000 top view.jpg
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  • Threshold 4000 front+top.jpg
    Threshold 4000 front+top.jpg
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  • Threshold 4000 and 400A PCB NO 053-0308.pdf
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  • Threshold 4000 VU Meter LED.jpg
    Threshold 4000 VU Meter LED.jpg
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  • Threshold 4000.jpg
    Threshold 4000.jpg
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  • Threshold 4000powersupply2.pdf
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  • Threshold 4000powersupply.pdf
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Mooved Schematic Archive from www_passlabs_com

This website was several time updated in the last ten years.

Where are presently to find follow archive sites:
Index of /np
Index of /np
Index of /np
time overview:
Internet Archive Wayback Machine

Thank you for your advices.

In the attachement the pdf file from previous post "Threshold 4000 and 400A PCB NO 053-0308.pdf" as tif-download and follow new pdf create - a bit better resolution
 

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  • Ganzseitiger Faxausdruck.pdf
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Threshold CAS Series - various schemas and pics

Threshold "CAS" series - various schemas and pics

CAS1 (CAS-1): schematics here:
http://www.diyaudio.com/forums/pass-labs/152646-threshold-cas-1-a.html (post #10)
http://www.diyaudio.com/forums/pass-labs/160310-threshold-cas-2-poweramp.html (post #4 and #6)
CAS2 (CAS-2): no schematics I have found, also not from the LED VU-Peak Level meter therefore.
AudiogoN Forums: Review: Threshold CAS-2 Amplifier

I don't find complete detailled schematics about the CAS2 (CAS-2) online. Who can post that?
 

Attachments

  • Threshold CAS2 front.pdf
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  • Threshold CAS2 open.pdf
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  • Threshold CAS2 open-II.pdf
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  • Threshold CAS 2 front rear.jpg
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  • Threshold CAS 2 front.jpg
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  • Threshold CAS 2 front-II.jpg
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  • CAS2 The Audio Journal Aug.1980-3.pdf
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  • CAS2 The Audio Journal Aug.1980-2.pdf
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  • CAS2 The Audio Journal Aug.1980-1.pdf
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E-Series Operations Manual (1 of 4)...
 

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