300b operating specs / reliability...

Discussion in 'Hi-Fi and General Audio' started by blakeaudio, Mar 2, 2005.

  1. blakeaudio

    blakeaudio

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    seems like there is ample plate dissipation in this puppy! i think this looks like a winner!
     
    blakeaudio, Mar 4, 2005
    #21
  2. blakeaudio

    alexs2

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    As long as the filament and grid voltages etc,plus pinouts are identical,then you should have no problems,and they are very robustly specc'd for 300Bs,albeit clones if you like rather than full replicas.
     
    alexs2, Mar 4, 2005
    #22
  3. blakeaudio

    blakeaudio

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    the amp:
    the tube:
    it seems the tube exceeds the requirement of the amp in every way. is it a problem if the amp provides a lower plate current and filament voltage? i thought (though i am certainly no expert...) that these were maximum rating and that the tubes would be better off seeing lower volages / currents? :confused:
     
    blakeaudio, Mar 4, 2005
    #23
  4. blakeaudio

    blakeaudio

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    blakeaudio, Mar 4, 2005
    #24
  5. blakeaudio

    alexs2

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    In general,it shouldn't be a problem,as long as there is sufficient to drive the tube adequately,and it may well be worth emailing VAC with your intentions regarding the tubes,to see what their advice is before buying what will obviously be a fairly expensive set of tubes.
     
    alexs2, Mar 4, 2005
    #25
  6. blakeaudio

    Chris Jennings

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    Quick note.

    The KR tubes mentioned take one and a half times the standard 300B filament current, make sure that the amp is capable of providing this.


    Chris
     
    Chris Jennings, Mar 5, 2005
    #26
  7. blakeaudio

    3DSonics away working hard on "it"

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    Hi,

    The VAC Amp's run their 300B's SERIOUSLY HARD. Lifespan is rather short. RUn like in the VAC even a WE 300B is only a 2,000 Hour Valve. I would suggest you avoid the VAC Amp's simply for that. You will not note much reduced SPL if you use an Amp that limits itself to only around 18 - 20W from a pair of 300B's but the lifespanm goes up no end, plus certain rather good sounding valves can be used (the TJ Mesh Anode 300B is NOT usable in the VAC). Also, the VAC uses the worst sounding PP Amp circuit (Williamson) and the worst sounding driver/input valve (6SN7) of the commonly found types.

    If you get an "open chassis" Amp you can always add a glass hood silimar to WAVAC to make it safe for kittens, puppies and rugrats.

    Even better, build your own and build it into a big 19" Case. You can build a stunning sounding Amp (consider a DRD with C3g driver and 300B plus type valve for > 15W SE) for a lot less than the VAC costs and just hide the plain 19" cases away.... ;-)

    Ciao T
     
    3DSonics, Mar 8, 2005
    #27
  8. blakeaudio

    blakeaudio

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    well, bonuses were announced yesterday and the unit that i was after was sold .... yesterday. NOT to me i hasten to add. so this is all a bit academic at the moment. the new price is very high, so i think i will be waiting a while before another used example comes up. i'm not willing to take that first owner depreciation....
     
    blakeaudio, Mar 8, 2005
    #28
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