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About congo5

  • Rank
    Limited Edition Bronze Participant

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  • Headphones
    Stax Sprit, stax sr-44, sr-80, SR-3 New. Fostex T50RPv2, Sennhieser HD535,Logitech G930 and many worse than these!
  • Headphone Amps
    BH,GG,Carbon,CFBHV,KGSSHV, KGST, MEGATRON,SRXPlus,current feedback & currentsourceamp2,KRELL clone, SINGLEPOWER Squarewave, FirstWatt F5
  • Sources
    creative X-fi titainum Turtle Beach DSS

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  1. KGSSHV Carbon Build Thread

    The problem with mounting the 10m90s for CCS 580v bias is that there is a lot of voltage on that metal tab I have not measured it but it has to be well over 600v the heatsink is 6/32 mount hole most times the transistor hole is too small for any PPS washer I have to fit they will crack if you force it and the PPS washers require a M3 or 4/40, so no 6/32 screw good news is there is not a lot of heat here as its putting out ~1.5ma so I have used a nylon 6/32 with 2mm oxide pad and thermal grease Peek would be better have also reamed out transistor hole before mounting to fit washers and 4/40 SS screw with nut through heat sink hole this is all covered in one of the older threads but they are large 600v when let loose is exciting and yes I have had flaming boards this is what I get away with YMMV
  2. KGSSHV Carbon Build Thread

    In the Blueman2 picture above it looks to me like a metal screw in the 10m90 for the headphone bias CCS And if so, do they make PPS washers that are white? It looks good but for that one concern thanks
  3. goldenreference low voltage power supply

    what zeners? no see um
  4. KG Balanced Dynahi build discussion thread

    The THAT340 is a sub for jfets, because they are hard to find and costly I changed mine because offset would move 100mv over the range of pot. in hindsight might be just wiring, or solvable with a couple resistors to ground. that pot /bjt input interaction could also cause noise sounds very good both ways
  5. The Multi Amp aka Dynalo Mk2

    What bias are you running? I turned mine down by stacking another resistor IIRC and have sinks glued to the top of transistors There is lots of copper on Kerry's board but a limited amount of surface area to dissipate heat. mine runs cooler in the case if I turn it on its side so air can rise vertically along the board surface. But yes ..............in a tiny case it runs hot. (from notes on ssdynalo mini) 255R bias +1.8k =223R avg .280mv/20R=14ma .28W
  6. KG Balanced Dynahi build discussion thread

    well then my Jfets are exactly backwards for K170 J74 but those are K246 J103 so OK (if it matters) they did work fine here but not so in Dynahi, used K170 J74 the silk is marked so Emitter – (E) >> Source – (S) Base – (B) >> Gate – (G) Collector – (C) >> Drain – (D)
  7. KG Balanced Dynahi build discussion thread

    I saved that pic but can't find it here is my SSDynalo with jfets N channel on top P channel on bottom
  8. current feedback electrostatic amp

    Looks to me like these could sub for input transistors. PBHV2160ZX And PBHV3160ZX data sheet is very much same except for lower collector and emitter capacitance Yes/No?
  9. current feedback electrostatic amp

    no its complete, SE in or BAL
  10. current feedback electrostatic amp

    at bottom center of each side are two holes for a solder loop or I plan to use spade connectors that is where Kevin put them and I copied his work Another benefit for the different caps are that they are shorter. So the board assembly is smaller
  11. current feedback electrostatic amp

    Yes I consider artistic ground planes "Fancy" This amp seems to have very good noise rejection as I can't hear anything. but why not have a ground plane...... This is what I will make next, when the parts come in Think this is better then my last, with ground plane, lower ESR and a bit smaller.
  12. and now for something completely different part 3

    File names are CFP2 which stands for Current Feedback Amp so sometimes referred to as CFA CFP2 is SE CFP3 is balanced and Large I have built dmt ver1.05, emt ver1.06, and had boards made and built fmt ver 1.07 which are 3.7" x 4" they all work gmt Ver1.09 is the newest from memory there were small changes only between them what part of schematic does not match? its been a while but will try to help
  13. current feedback electrostatic amp

    Here is what I drew up, no fancy ground plane like yours.......yet and why did I double the caps? dumbo turbo?
  14. current feedback electrostatic amp

    Absolutely agree with everything above! I often look up and admire my Dynahi, Dynalo and Kerry's mini as I plug into the CFA2
  15. current feedback electrostatic amp

    Thank You MLA It seems way better than expected, different but very very good.