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   Home » Melquiades Amplifier » Full range Melquiades implementation (82 posts, 5 pages)
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03-28-2015 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 10,156
Joined on 05-28-2004
Post #: 76
Post ID: 21610
Reply to: 21608
I can’t say anything about YO-186
fiogf49gjkf0d
I can’t say anything about YO-186. It looks like it is fine and the bias voltage or plate current did not move since I started to use it. I do not know how YO-186 edges however, it might be possible that she loose the cathode emission while holding the plate current.  Subjectively the sound is fine and since the tube is being used at a very conservative operation point I doubt that it somewhere at alarming cathode exhaustion. I wish I was able to test it with objective tester but I never was successful with DHT. I have a very interesting tube tested that might do it, the Royce Rolls of the tubes testers – the Russian L3, but I need to spend a good few days to become comfortable with it…

"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
03-28-2015 Post does not mapped to Knowledge Tree
decoud
United Kingdom
Posts 247
Joined on 03-01-2008
Post #: 77
Post ID: 21611
Reply to: 21607
Component drift
fiogf49gjkf0d
Thanks, Romy. What about drift in the driver bias, etc?
I suppose the liveliest component, in terms of dramatic breakdown, is the electrolytics. I have been thinking of changing to film, but in that size they are hard to find at reasonable prices.
03-28-2015 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 10,156
Joined on 05-28-2004
Post #: 78
Post ID: 21612
Reply to: 21611
Sure, why not.
fiogf49gjkf0d
 decoud wrote:
Thanks, Romy. What about drift in the driver bias, etc?
I suppose the liveliest component, in terms of dramatic breakdown, is the electrolytics. I have been thinking of changing to film, but in that size they are hard to find at reasonable prices.

I do not have any drift in the driver bias, it is dead stable in any Milq I tried. The electrolytic after the gas tubes is a very finicky subject. What I learned what I experimented with it that this last cap to ground after the gas tube does impact sound very dramatic. The selection of 10uF was not an accident but a result of many trials. A 2-3uF up or down did make difference in making sound more relaxed vs. to be more stringent.  I do not remember if I tried film, most likely I did and I did have large film caps. I however do not remember the result of film application. It might be worse to try different types of film not or to try to bypass the electrolytic with good film. I am saying it despite that I am not a huge fan of electrolytic bypass but of somebody want to experiment with it then the opportunity is there.
 

"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
03-29-2015 Post does not mapped to Knowledge Tree
decoud
United Kingdom
Posts 247
Joined on 03-01-2008
Post #: 79
Post ID: 21613
Reply to: 21612
Power supply caps
fiogf49gjkf0d
I have film in that position; I actually meant the 1000uf+ caps in the power supply. Hard to get those in film.... 
03-31-2018 Post does not mapped to Knowledge Tree
decoud
United Kingdom
Posts 247
Joined on 03-01-2008
Post #: 80
Post ID: 24773
Reply to: 21613
Snubber
Apologies for the primitive question, but has anyone optimised a snubber for Romy's full range circuit? My implementation does not have one, and I am for some reason now starting to get ringing on start-up of one channel.
03-31-2018 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 10,156
Joined on 05-28-2004
Post #: 81
Post ID: 24774
Reply to: 24773
This is normal
A ringing during warming up he is a typical behavior when a driver tube begin to age up. Replace it. 

"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
03-31-2018 Post does not mapped to Knowledge Tree
decoud
United Kingdom
Posts 247
Joined on 03-01-2008
Post #: 82
Post ID: 24775
Reply to: 24774
Solved
Many thanks, Romy: all is now well.
Page 4 of 4 (82 items) Select Pages:  « 1 2 3 4
   Target    Threads for related reading   Most recent post in related threads   Forum  Replies   Views   Started 
  »  New  Melquiades For Dummies™ - step by step...  Amp still open...  Melquiades Amplifier  Forum     28  213256  08-29-2007
  »  New  Building Melquiades: Chronicle of full-range..  VR2 issue leading to jump in current on 6C33 tube...  Melquiades Amplifier  Forum     44  432628  06-09-2006
  »  New  Building Melquiades: questions and answers...  PeaceMAT XS™...  Melquiades Amplifier  Forum     96  564230  10-09-2007
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