SDA SRS 2 + GFA 555 = WOW!!

Finally found a bigger amp at a reasonable price for the SDA's. Holy ****!! That is all... :o:o:):)
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Current Collection: Monitor 4a (Peerless), Monitor 5B (Peerless), Modified Monitor 7b (Peerless), RTA15TL (SL3000), SDA CRS+ (194’s), SDA SRS 2.3TL, R100's, R200’s, R300 🤩
Pairs that have passed through: Monitor 4b (Peerless), Monitor 5a (Peerless), Monitor 5b (SL1000), Monitor 5b (SL2000) (3x pair), Monitor 7b (Peerless), Modified Monitor 7c’s (194’s), Monitor 10a (Peerless), Monitor 10b (5x pair), RTA8, RTA8TL, RTA 11T, RTA12c (194's), SDA CRS, SDA 2 (2x pair), SDA 2a, SDA 2b, SDA 1b, SDA 1c, SDA SRS 2 (2x pair), SDA SRS 3.1TL (198’s) (2x pair)...and more to come, it’s a sickness.

Comments

  • FestYboy
    FestYboy Posts: 3,861
    Amazing what a little current will do... ;)
  • JayMX
    JayMX Posts: 434
    I’m considering it a Father’s Day present to myself! :D
    Current Collection: Monitor 4a (Peerless), Monitor 5B (Peerless), Modified Monitor 7b (Peerless), RTA15TL (SL3000), SDA CRS+ (194’s), SDA SRS 2.3TL, R100's, R200’s, R300 🤩
    Pairs that have passed through: Monitor 4b (Peerless), Monitor 5a (Peerless), Monitor 5b (SL1000), Monitor 5b (SL2000) (3x pair), Monitor 7b (Peerless), Modified Monitor 7c’s (194’s), Monitor 10a (Peerless), Monitor 10b (5x pair), RTA8, RTA8TL, RTA 11T, RTA12c (194's), SDA CRS, SDA 2 (2x pair), SDA 2a, SDA 2b, SDA 1b, SDA 1c, SDA SRS 2 (2x pair), SDA SRS 3.1TL (198’s) (2x pair)...and more to come, it’s a sickness.
  • JayMX
    JayMX Posts: 434
    I always thought the soundstage was impressive before, but it’s just amazing now. Channel separation is very impressive! Dead silent when it’s idling. Also, even at low levels there is a “meatyness” that I never experienced before. I am really amazed by this old gal! Love it!
    Current Collection: Monitor 4a (Peerless), Monitor 5B (Peerless), Modified Monitor 7b (Peerless), RTA15TL (SL3000), SDA CRS+ (194’s), SDA SRS 2.3TL, R100's, R200’s, R300 🤩
    Pairs that have passed through: Monitor 4b (Peerless), Monitor 5a (Peerless), Monitor 5b (SL1000), Monitor 5b (SL2000) (3x pair), Monitor 7b (Peerless), Modified Monitor 7c’s (194’s), Monitor 10a (Peerless), Monitor 10b (5x pair), RTA8, RTA8TL, RTA 11T, RTA12c (194's), SDA CRS, SDA 2 (2x pair), SDA 2a, SDA 2b, SDA 1b, SDA 1c, SDA SRS 2 (2x pair), SDA SRS 3.1TL (198’s) (2x pair)...and more to come, it’s a sickness.
  • Tony M
    Tony M Posts: 11,009
    So you got a Clean Adcom GFA-555 original Nelson Pass AMP? :oB)
    Most people just listen to music and watch movies. I EXPERIENCE them.
  • txcoastal1
    txcoastal1 Posts: 13,124
    Tony M wrote: »
    So you got a Clean Adcom GFA-555 original Nelson Pass AMP? :oB)

    :) John Curl
    2-channel: Modwright KWI-200 Integrated, Dynaudio C1-II Signatures
    Desktop rig: LSi7, Polk 110sub, Dayens Ampino amp, W4S DAC/pre, Sonos, JRiver
    Gear on standby: Melody 101 tube pre, Unison Research Simply Italy Integrated
    Gone to new homes: (Matt Polk's)Threshold Stasis SA12e monoblocks, Pass XA30.5 amp, Usher MD2 speakers, Dynaudio C4 platinum speakers, Modwright LS100 (voltz), Simaudio 780D DAC

    erat interfectorem cesar et **** dictatorem dicere a
  • motorstereo
    motorstereo Posts: 2,042
    txcoastal1 wrote: »
    Tony M wrote: »
    So you got a Clean Adcom GFA-555 original Nelson Pass AMP? :oB)

    :) John Curl

    You sure about that?

    Old 16th August 2002, 11:06 PM #2
    Nelson Pass is offline Nelson Pass United States
    The one and only
    Adcom 555II - Nelson Pass ?
    I designed the 555. I believe the Mk II added a couple
    of what were considered improvements, and it seemed
    to me that it included triple darlington outputs instead
    of 2 follower. I might have the schematic around, but
    all told it was a simple bipolar design with a current
    sourced input diff pair followed by a common-emitter
    gain device that was also current sourced. This drove
    the followers.

    It was typical of all the 5XXX amps that I did the first one
    and then they improved it until it had too many parts,
    and then I would design the next in the series

    Americo Borza sent me an old 555 in the hopes that I
    would update it, and it still sits here, a perfect candidate
    since so many of them were built.

    Personally, I would score a few of these and run them till
    they die and then update them. If you wait long enough,
    an update will be issued.
  • ZLTFUL
    ZLTFUL Posts: 5,640
    John Curl worked with Parasound while Nelson Pass worked with Adcom.
    "Some people find it easier to be conceited rather than correct."

    "Unwad those panties and have a good time man. We're all here to help each other, no matter how it might appear." DSkip
  • Tony M
    Tony M Posts: 11,009
    It amazes me that there are so many amp designs still being made.

    Why don't people just copy Nelson Pass's designs or other great designs of the past and present to get maximum performance? Is there copyright laws in effect for 30 years?
    Most people just listen to music and watch movies. I EXPERIENCE them.