Sda amp change

windstriker
windstriker Posts: 138
in Vintage Speakers
Ok I have to admit i have been fairly happy with my amp(gfa 555) paired with my 2bs and didnt think a amp change would make that big of difference. Boy was i wrong.... Just installed a belles 350a that is on loan. Compared to the gfa the sound is effortless and fuller. Imaging is more defined with singer less hazzy and there is a greater amount of separation with the instruments. Im also getting more of a sense of height a little more depth but not a lot. Very happy atm.
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Comments

  • Schurkey
    Schurkey Posts: 2,104
    Verify DC offset, recap and adjust the bias on those '555s and see what happens. I suspect they'll be more better. There's plenty of aftermarket upgrades for those, also.
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  • JayMX
    JayMX Posts: 446
    If you’re interested in updating your Adcom, check out Chris Hoppe's site. https://hoppesbrain.com/
    He offers some nice upgrade options for the 555's. Great (scary smart) guy, very unassuming if not a little strange in a mad scientist sort of way... I visited his home when I was in Madison WI for work last fall. Legit genius when it comes to all things Adcom. I purchased his “BFA” input board kit for my 555. Turns a Great F’ing Amp into a Better F'ing Amp... :) Dead silent, much greater separation, fantastic highs. Totally worth it. Thinking about doing his soft start kit soon too.
    x1a23q47pv1p.jpeg
    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) (4x 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.
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  • windstriker
    windstriker Posts: 138
    edited February 2020
    Ya I have thought about hoppes brain but almost feels like it wouldnt be the same amp after every thing was done. Ie it wouldnt be a gfa 555

    Did you do the upgrades your self? How difficult where they?
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  • dromunds
    dromunds Posts: 10,023
    Hoppes brain is apparently not taking any new work due to backlogs
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  • windstriker
    windstriker Posts: 138
    Ya Ive seen that message for at least a year. And i just went over the diy instructions. It does not seem to be a simple process. The most complicted electronics thing ive done is the sda upgrade which where pretty simple.
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  • JayMX
    JayMX Posts: 446
    I have a GFA 555 MK1 with the horizontal input board. He does offer kits for older models with vertical input boards. The project isn't really bad, just have to place the down-low components (resistors, diodes, etc...) on the board first then install the taller components. The boards are labeled very clearly so it's just follow the labels, populate and solder away... Once the board is assembled, you just move the existing wiring and RCA's (unless you want to upgrade them) to the new board and mount it up. Follow his testing procedures and biasing instructions and you should be good to go.
    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) (4x 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.
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  • audioluvr
    audioluvr Posts: 5,624
    The Belles is a Very nice sounding amp
    Gustard X26 Pro DAC
    Belles 21A Pre modded with Mundorf Supreme caps
    B&K M200 Sonata monoblocks refreshed and upgraded
    Polk SDA 1C's modded / 1000Va Dreadnaught
    Wireworld Silver Eclipse IC's and speaker cables
    Harman Kardon T65C w/Grado Gold. (Don't laugh. It sounds great!)

    There is about a 5% genetic difference between apes and men …but that difference is the difference between throwing your own poo when you are annoyed …and Einstein, Shakespeare and Miss January. by Dr. Sardonicus
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  • windstriker
    windstriker Posts: 138
    audioluvr wrote: »
    The Belles is a Very nice sounding amp

    Completly agree Im probably going to be able to barrow this one for a while(year or 2). May start saving up a get one of my own.
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  • Polar
    Polar Posts: 80
    windstriker wrote: »
    Ok I have to admit i have been fairly happy with my amp(gfa 555) paired with my 2bs and didnt think a amp change would make that big of difference. Boy was i wrong.... Just installed a belles 350a that is on loan. Compared to the gfa the sound is effortless and fuller. Imaging is more defined with singer less hazzy and there is a greater amount of separation with the instruments. Im also getting more of a sense of height a little more depth but not a lot. Very happy atm.

    Two things come to mind related to this: first, what preamp are you using? The GFA-555 I have was really not happy with a GTP preamp tuner (clear as a bell but ultra-flat stage), but it woke right up with a different preamp. Second, have you changed out the caps? Thirty year old caps can really cause some nasty artifacts ranging from mud to grittiness.

    One other thing I should mention - the GFA-555 design was very simple compared to some others I've seen (good Lord, open up a Carver amp sometime...) but that simplicity meant the soundstage was heavily dependent on the input board. If you have any components on that board that are end-of-life, out of calibration, or whatever, you'll have trouble. There have been a few players in that game, but right now the guy is Hoppes' Brain, as was mentioned earlier. He is a straight-up class act, a guy who is honest and takes his work quality very personally. He's making a living doing this, but he also gets a lot of joy out of it, and thats the right guy for our hobby.

    He is buried in work right now, but he does have boards and complete kits available. It really isn't that difficult to do, and the instructions for how to bias the amp when you're done are in the factory service manual, available on the web.
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  • windstriker
    windstriker Posts: 138
    belles dmc preamp
    The 555 is original parts
    I might one day do a kit but would rather get a pro todo it. Though as I said earlier I may get a bell or maybe some else. Haven't made up my mind but I have time to decide.
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  • Polar
    Polar Posts: 80
    windstriker wrote: »
    belles dmc preamp
    The 555 is original parts
    I might one day do a kit but would rather get a pro todo it. Though as I said earlier I may get a bell or maybe some else. Haven't made up my mind but I have time to decide.

    So, the borrowed Belles amp sounds better with the Belles preamp than the Adcom does.... :neutral:

    My store sold Hafler as well as NAD and Nakamichi amps. I bought Hafler on the advice of one of our salesmen, against the advice of another who preferred NAD. I used that DH220 for about 6 years. It sounded clean but not exceptional. I bought a GFA-555 after that, and I found that the Hafler sounded dead compared to it. I sold the Hafler.

    Years later, I picked up a Hafler SE240 as part of a deal. Same story: it sounds like a wet bucket of mud compared to almost anything else in my arsenal here. Yet some people tell me they prefer the Hafler sound. Maybe those people are using preamps and speakers that work better with Hafler amps? Maybe my ears just don't like the Hafler design approach?

    People debate combinations all the time, and I've had at least one "professional" insist that amplifiers do not - CAN NOT - change the sound, but anyone who's been around this hobby for a while can say otherwise from experience. Adding to that is the thought that perhaps a particular designer, engineer, or manufacturer might design their components so that they play nice with everyone but work best with their own gear.
    Now combine that with "expired" caps and perhaps some needed adjustments, and you have at least one potential reason that GFA-555 doesn't sound as good as the Belles. Or... perhaps your ears just appreciate the Belles sound more?
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  • Polar
    Polar Posts: 80
    I might add that even though I don't appreciate Hafler amps, I will cheer for their preamps, particularly the SE100/IRIS and the lowly DH100. Much better soundstage than anything I've heard at several times the price.

    Or is that my ears, again?
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  • audioluvr
    audioluvr Posts: 5,624
    Or maybe the Belles is just hands down better designed, built and sounding than the Adcom. As for Hafler stuff I've only heard the DH500 and XL600 both of which had their merits but things like a kettle drum sounded like hitting the back of your sofa with a wet sock. The Belles is WAY better than any of the Haflers I've heard.
    Gustard X26 Pro DAC
    Belles 21A Pre modded with Mundorf Supreme caps
    B&K M200 Sonata monoblocks refreshed and upgraded
    Polk SDA 1C's modded / 1000Va Dreadnaught
    Wireworld Silver Eclipse IC's and speaker cables
    Harman Kardon T65C w/Grado Gold. (Don't laugh. It sounds great!)

    There is about a 5% genetic difference between apes and men …but that difference is the difference between throwing your own poo when you are annoyed …and Einstein, Shakespeare and Miss January. by Dr. Sardonicus
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  • Polar
    Polar Posts: 80
    edited March 2020
    Everything I have in my house sounds way better than any Hafler amp I've heard - or owned. That includes every car amplifier I've owned.

    What does that mean, "hands down"? I've heard/read people using that term for years and its never made sense to me.
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  • Polar
    Polar Posts: 80
    audioluvr wrote: »
    Or maybe the Belles is just hands down better designed, built and sounding than the Adcom.

    I hope so. Its more than a few days newer than the GFA-555...
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  • audioluvr
    audioluvr Posts: 5,624
    Hands down: adverb
    English Language Learners Definition of hands down:
    informal
    : without much effort : very easily
    : without any doubt
    Gustard X26 Pro DAC
    Belles 21A Pre modded with Mundorf Supreme caps
    B&K M200 Sonata monoblocks refreshed and upgraded
    Polk SDA 1C's modded / 1000Va Dreadnaught
    Wireworld Silver Eclipse IC's and speaker cables
    Harman Kardon T65C w/Grado Gold. (Don't laugh. It sounds great!)

    There is about a 5% genetic difference between apes and men …but that difference is the difference between throwing your own poo when you are annoyed …and Einstein, Shakespeare and Miss January. by Dr. Sardonicus
    · Share on FacebookShare on Twitter
  • BlueBirdMusic
    BlueBirdMusic Posts: 2,335
    .... and .....

    The phrase hands down comes from horse racing, as explained by The Phrase Finder: Jockeys need to keep a tight rein in order to encourage their horse to run. Anyone who is so far ahead that he can afford to slacken off and still win he can drop his hands and loosen the reins - hence winning 'hands down'.
    "Sometimes you have to look to the past to understand where you are going in the future"

    Anger is just anger. It isn’t good. It isn’t bad. It just is. What you do with it is what matters.
    You can use it to build or to destroy. You just have to make the choice.     Jim Butcher




    Harry / Marietta GA
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  • Polar
    Polar Posts: 80
    Very interesting. I had also heard another explanation once that it related to debate Q&A. A view is presented, and people are asked to raise their hands if they have a rebuttal. "Hands down" is like saying "my view is superior, no rebuttal will apply, so hands down".
    In any case, I think its sort of a lazy buzzphrase.

    Thanks for the info, gentlemen.
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  • windstriker
    windstriker Posts: 138
    I do have a Cary pre that I am narrowing with the belles amp. When I put that in the system I will compare the two amps again
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  • sansuibutch
    sansuibutch Posts: 198
    I have tried countless combinations of amps and preamps. The latest and greatest combo yet for me is a recapped nad 1020 and a parrasound HCA-2200II.
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