have seen nelson pass adcoms, special?

scottyboy76
scottyboy76 Posts: 2,905
edited April 2011 in Electronics
Who is this guy, what did he do for certain adcoms, and should i look for it when considering buying an amp.

I have just seen a 555 nelson pass design on cl for 325, fine shape according to seller.

Any thoughts?
humpty dumpty was pushed
Post edited by scottyboy76 on
· Share on FacebookShare on Twitter

Comments

  • cokewithvanilla
    cokewithvanilla Posts: 1,777
    edited April 2011
    http://www.passlabs.com/

    he designed some of their amps... he's supposed to be a good designer. However, just because he designed it, doesn't mean he didn't have to cut 50 corners due to cost.

    I'm sure others will chime in with direct comparisons.
    · Share on FacebookShare on Twitter
  • leroyjr1
    leroyjr1 Posts: 8,785
    edited April 2011
    The Adcom 5802 is Adcom's best amp and it's a good performer.
    · Share on FacebookShare on Twitter
  • FTGV
    FTGV Posts: 3,649
    edited April 2011
    who is this guy?
    Mr.Pass is one of the preeminent amplifier designers of the last 30yrs.
    · Share on FacebookShare on Twitter
  • Tony M
    Tony M Posts: 11,285
    edited April 2011
    Nakamichi Stasis amplification designer to.:wink:

    I had one and it did sound like an Adcom GFA-555 come to think of it.
    Most people just listen to music and watch movies. I EXPERIENCE them.
    · Share on FacebookShare on Twitter
  • FTGV
    FTGV Posts: 3,649
    edited April 2011
    tony millard wrote: »
    Nakamichi Stasis amplification designer to.:wink:

    Stasis was originally his brainchild for Thresold,he just let the generous folk at Nak pay him a user licence.
    · Share on FacebookShare on Twitter
  • cnh
    cnh Posts: 13,284
    edited April 2011
    What the guys said above. As for the GFA-555, GFA-545 ORIGINALS, they are widely considered the 'best' of those series as Adcom introduced 'noise' into Pass's design in later models...although no deal breaker.

    And the GFA-5802 was, as Leroy points out, the most prodigious of the lot!

    H9 knows all this history in great detail. Do a search on Adcom for heiney9's posts, and you'll get ALL the info you need.

    As for the price. Try to get down to 300 or less if you can. Those Adcom originals were little giant killers when they first hit the market...cost cutting or not.


    cnh
    Currently orbiting Bowie's Blackstar.!

    Polk Lsi-7s, Def Tech 8" sub, HK 3490, HK HD 990 (CDP/DAC), AKG Q701s
    [sig. changed on a monthly basis as I rotate in and out of my stash]
    · Share on FacebookShare on Twitter
  • Toolfan66
    Toolfan66 Posts: 17,453
    edited April 2011
    GFA-5802 is a beast!!!
    · Share on FacebookShare on Twitter
  • erniejade
    erniejade Posts: 6,321
    edited April 2011
    So what makes the 5802 sound that much over the 555? Just wondering. I might be looking for a new amp. I just change amps a lot. I have a 555 so besides 100 more watts, whats the sound difference? Was the 5802 part of the leaky cap series?
    Klipsch The Nines, Audioquest Thunderbird Interconnect, Innuos Zen MK3 W4S recovery, Revolution Audio Labs USB & Ethernet, Border Patrol SE-I, Audioquest Niagara 5000 & Thunder, Cullen Crossover II PC's.
    · Share on FacebookShare on Twitter
  • FTGV
    FTGV Posts: 3,649
    edited April 2011
    erniejade wrote: »
    So what makes the 5802 sound that much over the 555?
    I can't speak to the sonic differences between the two but there are some important technical differences that would explain them.First the 5802 uses Mosfets as the output devices vs Bipolar transistors in the 555.The power supply designs differ in that the 5802 actually has two seaparte supplies,one dedicated strictly to the input stage and a very large one with substantial filter capacitance for the output section.The 555 uses a single supply with less total capacitance than in the 5802.I believe the input stage would be somewhat different amongst other important circuit differences, ie.the 5802 being biased higher so as to have a larger percentage of it's output being in Class A.
    · Share on FacebookShare on Twitter
  • FTGV
    FTGV Posts: 3,649
    edited April 2011
    erniejade wrote: »
    Was the 5802 part of the leaky cap series?
    IIRC that was only a problem with certain 565's and/or 585s.
    · Share on FacebookShare on Twitter
  • erniejade
    erniejade Posts: 6,321
    edited April 2011
    Thanks so sonicaly i would think warmer and more natural with the mosfets

    Thanks for the reply!
    Klipsch The Nines, Audioquest Thunderbird Interconnect, Innuos Zen MK3 W4S recovery, Revolution Audio Labs USB & Ethernet, Border Patrol SE-I, Audioquest Niagara 5000 & Thunder, Cullen Crossover II PC's.
    · Share on FacebookShare on Twitter
  • cstmar01
    cstmar01 Posts: 4,424
    edited April 2011
    No the 5802 was not affected by the leaky caps at all. The 5802 is a very good amp with lots of grunt. It was/still is a very good amp for the money and you should be able to pick them up used between 650-900 on the gon.
    · Share on FacebookShare on Twitter
  • heiney9
    heiney9 Posts: 25,248
    edited April 2011
    erniejade wrote: »
    So what makes the 5802 sound that much over the 555? Just wondering. I might be looking for a new amp. I just change amps a lot. I have a 555 so besides 100 more watts, whats the sound difference? Was the 5802 part of the leaky cap series?

    Better built, more involvement with Nelson Pass.........overall a better design, with better parts and about 3X the retail price. The 5802 is much sweeter sounding the 555. It has more authority is all around much more refined than the 555.

    To the OP, do a search, I've covered this subject exhaustively with all kinds of links, etc. No way am I recapping it again.

    The 5802 has no leaky cap issue. The 565's and 585's had that issue with some caps that were supplied from an outside manufacturer.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Puritan Audio PSM136 Pwr Condtioner & Classic PC's | Legend L600 | BlueSound Node3 - Tubes add soul!
    · Share on FacebookShare on Twitter
  • heiney9
    heiney9 Posts: 25,248
    edited April 2011
    cokewithvanilla wrote: »
    http://www.passlabs.com/

    he designed some of their amps... he's supposed to be a good designer. However, just because he designed it, doesn't mean he didn't have to cut 50 corners due to cost.

    I'm sure others will chime in with direct comparisons.

    The original 555 was a good amp and they didn't mess with Nelson's original too much.........later version's were altered quite a bit comparatively .(555 MKII, 5800).

    FTR, the "he" you are referring to was NOT Nelson cutting corners, it was the final design engineers and bean counters at Adcom. He (being Nelson) had nothing to do with Adcom. All Nelson did was send them a few prototypes which Adcom then tweaked in certain area's to be cost effective. The original 5xx series were excellent for their day and still are very good amps. I'm sure some are getting long in the tooth because of age so keep that in mind.

    I posted a link awhile ago. Here it is.

    http://www.linearaudio.nl/interviews/np.pdf
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Puritan Audio PSM136 Pwr Condtioner & Classic PC's | Legend L600 | BlueSound Node3 - Tubes add soul!
    · Share on FacebookShare on Twitter
  • heiney9
    heiney9 Posts: 25,248
    edited April 2011
    tony millard wrote: »
    Nakamichi Stasis amplification designer to.:wink:

    I had one and it did sound like an Adcom GFA-555 come to think of it.

    Really, I've heard both extensively and to my ears they sound quite different. They are completely different designs. Nakamichi paid to license the Stasis circuit from Threshold when Nelson was one of the owners.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Puritan Audio PSM136 Pwr Condtioner & Classic PC's | Legend L600 | BlueSound Node3 - Tubes add soul!
    · Share on FacebookShare on Twitter
  • leftwinger57
    leftwinger57 Posts: 2,917
    edited April 2011
    Besides the obvious rack mounting face plate are there any difference to the one I own which is the industral style that I call it or the more refined ribbed front of the mkII.
    And again I must plug Audio Classics for a pristine example of a hevy duty hard working
    power amp that seems never to get even warm for $300 w/ shipping included......LW
    2chl- Adcom GFA- 555-Onkyo P-3150v pre/amp- JVC-QL-A200 tt- Denon 1940 ci cdp- Adcom GFS-6 -Modded '87 SDA 2Bs - Dynamat Ext.- BH-5- X-Overs VR-3, RDO-194 tweeters, Larry's Rings, Speakon/Neutrik I/C- Cherry stain tops Advent Maestros,Ohm model E

    H/T- Toshiba au40" flat- Yamaha RX- V665 avr- YSD-11 Dock- I-Pod- Klipsch #400HD Speaker set-

    Bdrm- Nikko 6065 receiver- JBL -G-200s--Pioneer 305 headphones--Sony CE375-5 disc
    · Share on FacebookShare on Twitter
  • heiney9
    heiney9 Posts: 25,248
    edited April 2011
    MK 1 and MK 2 had ribbed fronts. Yours most likely is an early 555. The very early production 555's had a smooth front plate like the GFA 1 and GFA 2. Perhaps they were using up left over chassis. I believe they made an "industrial" version of the 555 early on......but I have no idea if there are internal differences or just the rack mount capability.

    Ribbed front plates were used on MK1 and MK2 models so you can't say the ribbed fronts were only MK2 amps.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Puritan Audio PSM136 Pwr Condtioner & Classic PC's | Legend L600 | BlueSound Node3 - Tubes add soul!
    · Share on FacebookShare on Twitter
  • erniejade
    erniejade Posts: 6,321
    edited April 2011
    Thanks H9

    I saw this thread and saw it was mentioned so I figured i would ask. I am just thinking of my next amp when i up one of the sunfires up. I was thinking of either the 5802 or a parasound 3500 . I have not decided on anything yet.
    Klipsch The Nines, Audioquest Thunderbird Interconnect, Innuos Zen MK3 W4S recovery, Revolution Audio Labs USB & Ethernet, Border Patrol SE-I, Audioquest Niagara 5000 & Thunder, Cullen Crossover II PC's.
    · Share on FacebookShare on Twitter
  • [Deleted User]
    [Deleted User] Posts: 1,225
    edited April 2011
    heiney9 wrote: »
    The 5802 has no leaky cap issue. The 565's and 585's had that issue with some caps that were supplied from an outside manufacturer.

    H9

    Were the Adcom 535 amps prone to the leaky caps as well or was that just the larger amps ? I just bought a 535 and was wondering are there any other known issues with them ? :cool:
    · Share on FacebookShare on Twitter
  • heiney9
    heiney9 Posts: 25,248
    edited April 2011
    nap wrote: »
    Were the Adcom 535 amps prone to the leaky caps as well or was that just the larger amps ? I just bought a 535 and was wondering are there any other known issues with them ? :cool:

    Nope, and I'm not trying to be flippant but I'll say it one more and hopefully last time.

    ONLY some 585's and 565's mono blocks

    It probably could use a recap if it's an original 535.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Puritan Audio PSM136 Pwr Condtioner & Classic PC's | Legend L600 | BlueSound Node3 - Tubes add soul!
    · Share on FacebookShare on Twitter
  • [Deleted User]
    [Deleted User] Posts: 1,225
    edited April 2011
    heiney9 wrote: »
    Nope, and I'm not trying to be flippant but I'll say it one more and hopefully last time.

    ONLY some 585's and 565's mono blocks

    It probably could use a recap if it's an original 535.

    H9

    Okay thanks, was only wondering. :cool:
    · Share on FacebookShare on Twitter
  • heiney9
    heiney9 Posts: 25,248
    edited April 2011
    nap wrote: »
    Okay thanks, was only wondering. :cool:

    No problem Tony, better to be sure than always wondering. :smile:

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass Pass Labs XA25 | EE Avant Pre | EE Mini Max Supreme DAC | MIT Shotgun S1 | Puritan Audio PSM136 Pwr Condtioner & Classic PC's | Legend L600 | BlueSound Node3 - Tubes add soul!
    · Share on FacebookShare on Twitter