From: apogosso@tpg.com.au   
      
   "patrick-turner"  wrote in message   
   news:0bad46cc-e336-417e-ac98-.....   
      
   But your statement "Definitely such insulator will give a "wooden" sound --   
   shallow, flaccid, limp bass." - is utter rubbish because the bass quality of   
   the reformed Jadis is nothing short of spectacular, and sounds like a good   
   50W amp.   
      
      
      
   ***   
   I was only kidding and teasing. Sorry if you took offence.   
      
   Probably wood is OK if you do not drive +500V screws near some sensitive   
   grid circuits screws... But I would not use timber. Teflon is very costly,   
   of course, so I use polysterene sheets or even pieces of kitchen plastic   
   cutting boards, but they are not high temperature material. Only low power   
   circuits can be laid out on them.   
   ***   
      
      
      
   Real audiophools with determinations always use teflon -- no absorbtion, no   
   leakage, easily machined, cut, drilled.   
      
   Audiophules with determination like to believe they know best by using   
   teflon that almost nobody else uses because of cost and difficulty in its   
   use and the inability to use glue to fix it. Audiopules are notoriously   
   pig-ignorant, knowing almost zero about real world electronic or metal   
   engineering or about electronic properties of material and how they affect   
   distortions and noise and sound. What they DO KNOW is mostly a jumble of   
   bullshit notions not based on any known facts, but based on "what others   
   have said" on the Net, and on slaes BS and on what Stereophile authors have   
   poked down their necks. They then profess to be able to tell if any special   
   capacitor brand has been used or special wore of special any fukken thing.   
   Fact is, when I have yested their perceptive abilities, they rarely can pick   
   whether I have used Wima caps or Auricaps, teflon or polyester, or any   
   difference between either solid state amps I have made, or tube amps. Turns   
   out the audio enthusiasts who are not complete raving loonies like whatever   
   I make.   
      
   You can dril blind holes and drive screws and pins into them. Will not   
   carbonise, burn or change properties when overheated during soldering or   
   when a component is burning.   
      
   I understand all that, and would love to used 10mm x 10mm bars of teflon to   
   make up circuit terminal strips. Its fiendishly expensive stuff. Probably,   
   like so many modern plastics, its production causes an environmental   
   nightmare somewhere.   
   The amps I build rarely ever need to be worked on later because anything to   
   be done by anyone other than myself would make things worse, because nobody   
   understands his own product better than me.   
   So, having wired up the Jadis with a few hardwood plywood boards and   
   hardwood terminal strips using brass plated steel cupboard hinge screws for   
   terminals, its more than likely they'll never ever be changed. If someone   
   were to acquire what I have done and replace terrible horrid wood with   
   teflon, they'd be telling a whopping lie if they insisted it sounded better.   
   One could say music should sound organically wondrous, and be supported on   
   natural substances where possible, including wood, and iron, copper, silicon   
   because all are natural, ie, found on our planet, without much monstering   
   and adulteration by industry. Wood Knot Teflon sound clinical, dry, souless,   
   empty,and unacceptable? Bloody audiopule arguments can be reversed back onto   
   the stupid bastards. Fact is Jadis SE300W amps were a bloody horror story,   
   and now at least just TWO samples sound wonderful. The Jadis site says they   
   are discontinued, and I guess, and I am only guessing, maybe all samples of   
   that model had OPTs without any air gap, plus the whole pile of other   
   circuit mistakes and design mistakes which made +1,000 dB more worsening of   
   sound than any timber board for CCS transistor and protection board, and   
   test terminals for monitoring Iadc and Iac of each 300B without needing to   
   move it.   
      
   Also I noticed that balancing of the filaments of 300Bs with 33R series   
   resistors is unnecessary. With the DC filament supply, one end of the   
   filament is ALWAYS 5V higher or lower, no matter where the self-bias circuit   
   is connected.   
      
   There is few mV of hum across the cathodes. Its negligible. But when I made   
   amps with 845, guess what, even with cathode Vdc and few mV of hum, a   
   fraction of a mV got into output so balancing is GOOD PRACTICE even though   
   you say its BS.   
      
   Thus the last 5V of the grid voltage swing is underused, because grid   
   current from the more negative end of the cathode will prevent full emission   
   on the more positive end.   
      
   In theory, you are correct, in practice, its BS. The difference in emission   
   along the cathode is utterly negligible and unimportant to operation. Would   
   you care to quantify your argument? Jadis had used a regulated 5Vdc for 300B   
   and hum was less than a mV, but they had two balancing 47r resistors.   
   Trouble weas they used just one 5Vdc supply common to both 300B - big   
   mistake when tubes are not matched, and running too hot anyway. The very   
   slight amount of unbypassed resistance in my TWO reformed Rk+Ck circuits =   
   38 ohms, and the very slight amount of local current FB does SFA good, bad,   
   or otherwise except stop the two parallel cathode bypass caps ever being   
   over currented with AC from low Z of 300B cathode. Not likely in fact.   
      
   Similraly, this 5V skew smears the tube cut-off -- one end might be cut-off   
   while the other is conducting.   
      
   This is a hi-fi use of class A 300B and they never go anywhere near cut off.   
   Your argument does not hold water.   
      
   Besides the cathode is wearing unevenly, one end always bearing more   
   emission current, but this should not be a tube life limiting factor.   
      
   And it just does not matter!   
      
   So this balancing is just a sterotypical thinking.   
      
   The balancing was a necessity where AC was routinely used in many amps for   
   heating. Usually a hum nulling pot was used, and even in PP amps the nulling   
   is never perfect and in a pair of Sun amps with 2A3 I repaired 10 years ago   
   the AC heating and pot were retained, and I gave a pair of headphones the   
   owner could use for nulling. That worked, and noise only seldom appeared at   
   speakers. My 55W SE55 with 845 had less than 0.25mV of total noise at   
   output. I know all about how to build amps with low noise, and I'll do it my   
   way, and not yours.   
      
   The four 33R resistors can be safely removed.   
      
   Indeed, but they are staying put.   
      
   Now, depending on whether the self-bias circuit is connected to a positive   
   or a negative end of the filament, one would have less or more fixed bias   
   mixed respectively.   
      
   The Reformed Jadis now have individual R&C cathode biasing. Audio Note makes   
      
   [continued in next message]   
      
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    * Origin: you cannot sedate... all the things you hate (1:229/2)