Bi-amping SDA SRS

n8thesk8
n8thesk8 Posts: 13
edited February 2013 in Vintage Speakers
Good morning everyone, I have a pair of SDA SRS's I would like to bi-amp. I have a Adcom GFA-565 SE for the bottom end. I have several amps to choose for the highs. What I have to choose from is, Yamaha M-45, M-60, and M-70. A Sansui B 2102. Adcom GFA 545 ii. Heath AA 2500 and an Adcom GFA 1. The last time I bi-amped I used the Yamaha M-45 and M-60. It was ok for low volume but that was it. No mods to the speakers. Thanks for and input.
N8
When the music's over...turn out the light.
Post edited by n8thesk8 on

Comments

  • Schurkey
    Schurkey Posts: 2,101
    edited February 2013
    How do you plan to get the treble volume matched to the bass volume?

    First Guess: You'll have much better sound quality by NOT bi-amping, put the time, money, effort, and enthusiasm into freshening the crossovers and the various other recommended mods.
  • n8thesk8
    n8thesk8 Posts: 13
    edited February 2013
    I use the GFA-565 SE right now. Its 300 wpc at 4 ohms. I'm not sure I understand your question matching treble volume to the bass.
    When the music's over...turn out the light.
  • Schurkey
    Schurkey Posts: 2,101
    edited February 2013
    Vertical bi-amping: One amp drives the bass. One amp drives the treble. Unlikely that both amps have the same gain. Therefore, you're going to have to manually match the treble volume to the bass volume. How are you going to do that?

    Thus my suggestion to concentrate on improving the speakers vs. adding additional amplifiers.
  • OldmanSRS
    OldmanSRS Posts: 419
    edited February 2013
    IMO, bi-amping gets you little to nothing. No advantage and it makes things more complex with gain matching etc.

    Been there with dual Carver amps.
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  • motorstereo
    motorstereo Posts: 2,133
    edited February 2013
    You could match the bass and treble by using the gain knobs on the amps. But I agree with the others after trying out vertical bi-amping for myself. There's very little if anything to be gained here. Buy one really nice amp and you'll soon forget all about bi-amping.
  • txcoastal1
    txcoastal1 Posts: 13,287
    edited February 2013
    You could match the bass and treble by using the gain knobs on the amps.

    Nope....
    adcom-gfa-565se.jpg
    No gain knobs
    2-channel: Modwright KWI-200 Integrated, Dynaudio C1-II Signatures
    Desktop rig: LSi7, Polk 110sub, Dayens Ampino amp, W4S DAC/pre, Sonos, JRiver
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  • F1nut
    F1nut Posts: 50,557
    edited February 2013
    Very few amps come with gain controls.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • n8thesk8
    n8thesk8 Posts: 13
    edited February 2013
    I guess I'll try at least one just to say I did.
    When the music's over...turn out the light.
  • F1nut
    F1nut Posts: 50,557
    edited February 2013
    Don't bother, it will never sound right with mis-matched amps.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • nhhiep
    nhhiep Posts: 877
    edited February 2013
    that is a mess. how about sell most of the unused amps and buy another Adcom GFA-565 SE?
    or just sell everything and buy an emotiva amp
  • F1nut
    F1nut Posts: 50,557
    edited February 2013
    or just sell everything and buy a high quality amp

    Fixed it for ya.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • motorstereo
    motorstereo Posts: 2,133
    edited February 2013
    I was thinking the yammys he mentioned have gain controls if he wanted to go that route. The adcoms don't even have speaker relays let alone gain controls.
  • Dawgfish
    Dawgfish Posts: 2,554
    edited February 2013
    I would normally agree with the others on this and say buy one good quality amp, or two of the same amps to biamp. However if you already have a bunch of amps lying around, and you have two pairs of matching ICs and speaker cables, give it a try just to see for yourself. You never know, it may workout. Of the combos you mentioned above I would try the Adcom 565 on the lows and the 545 on the highs because they would most likely sound the most alike and have similiar gain characteristics.

    The reason I'm telling you to give it a try is because I decided to do just that on my SRS 2s and I was surprised with the results. I was running my SRS 2s with a Rogue Magnum 88 and I bought a Primaluna Prolugue 4 to use on another system. Just for grins and giggles I decided to try the Primaluna on the highs and the Rogue on the lows. It sounds awesome! To my ears the balance between the lows and highs is perfect and it sounds great. I was really expecting it to sound like a mis-matched mess, but instead it sounds perfect to my ears. Needless to say, I'm keeping it this way and I'm not moving the PL to the other system. I lucked out in that the gain characteristics between the two amps is very similiar. YMMV, but I say if you have the equipment, give it a try for yourself and see what you think. You'll never really know until you try.
  • n8thesk8
    n8thesk8 Posts: 13
    edited February 2013
    I think I'll take F1nut's advice for now and just leave it. It does sound good. I don't have the funds for another amp and I don't want to sell any of my other amps.
    When the music's over...turn out the light.
  • n8thesk8
    n8thesk8 Posts: 13
    edited February 2013
    Well I had some time before work so I hooked my M 60 up to the highs and wow I never thought it would have made such a difference. Makes low volume listening much better.
    N8
    When the music's over...turn out the light.
  • EndersShadow
    EndersShadow Posts: 17,590
    edited February 2013
    F1nut wrote: »
    Very few amps come with gain controls.

    While true there are a bunch out there that are not too hard to find, almost all used like Carvers x series amps (AV-705x, 505x, 404x), and B&K has a bunch (including the one FS in the flea market currently).
    "....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963)
  • Schurkey
    Schurkey Posts: 2,101
    edited February 2013
    or just sell everything and buy a high quality amp
    F1nut wrote: »
    Fixed it for ya.
    Thank you.

    Emotiva = Chinese bottom-feeder. NOBODY goes to China to improve quality. Companies source from China and other Communist countries to improve profit margins.
  • nhhiep
    nhhiep Posts: 877
    edited February 2013
    Schurkey wrote: »
    Thank you.

    Emotiva = Chinese bottom-feeder. NOBODY goes to China to improve quality. Companies source from China and other Communist countries to improve profit margins.

    want to guess where they make LsiM? Iphone, and most things that you're using now?
  • Schurkey
    Schurkey Posts: 2,101
    edited February 2013
    nhhiep wrote: »
    want to guess where they make LsiM? Iphone, and most things that you're using now?
    Exactly right. Improved (obscene) profit margins on all of the above.

    Buying Chinese when there's still American, North American, or Free World alternatives is both very silly, and very harmful.

    The Chinese and the Communist Collaborators in this country have already destroyed enormous swaths of (North) American Industry, and put the American economy on a downward spiral. Don't encourage them to destroy even more.
  • nhhiep
    nhhiep Posts: 877
    edited February 2013
    so, why are we still buy Polk speakers? My pt is it's all about QC, regardless where it's made. Everywhere I read, Emotiva is the best bang for buck. Same with Polk. But here we're supporting Polk, yet say Emotiva is junk?