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About georgehifi

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  • Birthday May 14

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    Manly nsw
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  1. georgehifi

    Measurements on stock vs a modded oppo105

    Yeah, in a bad way, everything is far worse for the modded one. Cheers George
  2. Every ESL owner/fiddler needs one of these Sensitive Research Electrostatic Volt Meters if they can find one still working. Measuring ESL's B+ without one is impossible. Cheers George
  3. georgehifi

    Current of Amp

    So we can safely go back to this statement above, and say that if you heard no altering of the frequency response difference, that your solid state amp has the same output impedance (damping factor) as the vsi has which is a pretty lousy 4DF or 2ohms output impedance, and this I have never seen with a solid state amp, even one with no global NFB, unless it had 2ohm emitter resistors with no GNFB and who would do that I have no idea. Cheers George
  4. georgehifi

    Current of Amp

    I can say nearly 100% all of these speakers looking around the web at their impedance graphs, would make AR vsi75 with a DF of only 4, give a frequency response from 20hz to 20khz that would look like a tone control, such as the "grey trace" in the graph below. The others 4 coloured traces are pure steady state resistance loads which speakers are not. Cheers George
  5. georgehifi

    Current of Amp

    It's about the same, this is from Audio Research on the VSI75 at 8ohms "Damping Factor approximately 4". This means it's output impedance is around 2ohms, this is not a good figure to get great tight low powerfull bass with. Most good solid states should sound better in the bass. If this amp sounded as good in the bass as a good solid state, then the only way it could have happened is if the speakers as I said before were dead flat 8ohm impedance from 20hz to 20khz Which speakers are these you have?? Cheers George
  6. georgehifi

    Current of Amp

    All I can say to that is your solid state amp must have a very high (for SS) output impedance (low damping factor) if it isn't flatter than the AR with a normal speaker load. Unless that speaker load you a/b'd them with had a benign very flat impedance curve from 20hz to 20khz . Because here is the frequency response of the AR VSI60 (same circuitry as the 70) into the easy simulated Kantor speaker load (Grey Trace) If a solid state amp can't better this, then it must be ?????'able Cheers George
  7. georgehifi

    2 power amps from single pre out

    Just to add for advantages of vertical passive bi-amping, the mids and highs will also benefit as the channel that doing them will not be comming out of Class-A bias so early, as it's not looking at the bass loading and going into Class-B. So the just the mids and highs should also stay sweeter for the louder climaxes/dynamics. As well as the bass benefiting from more power supply head room from the other channel. So it's a win all round Serg @husq2100 Cheers George
  8. georgehifi

    2 power amps from single pre out

    That's all he wants, as he said he got the extra Nad here probably cheap, and wants the best with what he has. And all he has to do is get the 2 x 2 way rca splitter for $10 and he has better sound than one will give, especially in the bass drive department because he'll have far better power supply reserves to call on.. Cheers George
  9. georgehifi

    2 power amps from single pre out

    Jeez Dave the guys got two cheap amps and he wants to do something with them with what he has, that easy and cheap and going to give better sound, he doesn't want to reinvent the wheel. Cheers George
  10. georgehifi

    2 power amps from single pre out

    If he does then Dave's statement "It offers no significant benefit at all." has something, if anything it's worse than just having a single stereo amp, having 2 x bridged ones. Cheers George
  11. georgehifi

    FS: Luxman MB -3045 Monoblock

    Yum, these were great with my quad 57's. I had the similar MB88 earlier ones with big horseshoe shaped chrome side handles. Although it marked Luxman on the output transformers, they were actually the famed Tango's made for Lux by Tango, and yours seem similar, maybe they are too. Lovey amps GLWTS Cheers George
  12. georgehifi

    2 power amps from single pre out

    Yeah agree, but I don't think he meant bridged rather bi-amped. Beside bridging an amp is not such a good thing, the only plus it has is more watts. Distortion, damping factor, stability, and low impedance drive ability all take a hit for the worse when an amp is bridged. Cheers george
  13. georgehifi

    2 power amps from single pre out

    Just go the way you were as you first stated, I got the gist of what you were doing. With your identical amps just use one amp per speaker in what they call vertical passive bi-amping. One amp per speaker, one channel for mid/highs the other for bass. The drive both the amps with the rca spliter I linked you to with your M51. And you will get a better sound than just using one amp, as the powersupply of both will be cruising. Nice and simple as you say KISS. No more money spent or extra complexity. Then down the track if you feel you want to improve again, yes bypass the internal xover (not a 5min job) of the speakers and buy an active two or tree way x-over and start the big job of dialling everything in (this can take weeks to get right depending how anal you are) I am and I did. Cheers George
  14. georgehifi

    2 power amps from single pre out

    Dave you can never have a big enough power supply, why do you think the ME amps are so good in the bass, beside other things, a massive transformers and big uf count, Same goes for Krell ect. And the NAD C275BEE is a far cry from an ME power supply, so why not make life easier for it in the bass where most grunt is needed by making only supply one channel. Cheers George
  15. georgehifi

    Current of Amp

    We all know tubes soft clip, but when they do in the bass they sound rubbish. No matter what you try to say, a tube is never ever going to give the current drive that a good solid state can, the above graphs prove it. They act like a tone controls into speakers, and start to sag at the first signs of low impedance dips, giving them a frequency response that is far from flat. The AR Ref 150se you cited from it's 4ohm tap can at .2%thd give 70w into an 8ohm speaker, but if that speaker dips to 4ohms which many do in the bass it only gives a pathetic 9watts at .2%thd, more and the thd starts rising rapidly. Cheer George