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Old 19th February 2009, 10:50 PM   #1051
Salas is offline Salas  Greece
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Those caps I will shortly try for interstage coupling. May be cool.
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Old 19th February 2009, 11:46 PM   #1052
Salas is offline Salas  Greece
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Default Valve itch

I am also thinking of ideas about a new valve phono to make. Trying to do better than the Bench one, bcs the Simplistic NJFET overachieved it. So I made a preliminary design based on 2 mu followers in cascade like in phono dude. I have E283CC and 6CG7 which are low noise, better 12AX7 with funny pin out, and noval 6SN7. This one can do 44dB, good for down to 2mV high MC. Must share low valves and high valves between channels, with the high valves heaters lifted at 100V. It can do 38dB if first valve is 6SL7 and the first stage 47k must be substituted for 33k. No problem with real MM or X10 step up. Nice full octal variant if second valve will be 6SN7. There is a good stash of flavors with many people. I guess that I will try it at a point. No definitive plans yet.
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Old 19th February 2009, 11:47 PM   #1053
Salas is offline Salas  Greece
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And its HV shunt reg psu mate off course. Not fare to compare without.
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Old 19th February 2009, 11:54 PM   #1054
RCruz is offline RCruz  Switzerland
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I like the valve setup...
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Old 19th February 2009, 11:59 PM   #1055
Salas is offline Salas  Greece
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I have a 15720pF Ruskie like yours in a Simplistic Riaa and I will add 330pF tomorrow, so to measure before and after for you... I generally want it nearer to 16n or a little over than lower, bcs it can pick up HF especially with some bright carts.
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Old 20th February 2009, 12:06 AM   #1056
Salas is offline Salas  Greece
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And if with a normal or low MC there are simple ideas for step up without much compromise and low cost. Maybe better than many mediocre step up transformers. That was made by Frank and posted here in 2003.
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Old 20th February 2009, 12:08 AM   #1057
Salas is offline Salas  Greece
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And this one is from original pacific. Its pre pre part.
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Old 20th February 2009, 12:22 AM   #1058
Salas is offline Salas  Greece
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Homeless...
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Old 20th February 2009, 12:27 AM   #1059
massimo is offline massimo  Italy
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Quote:
Originally posted by salas
And this one is from original pacific. Its pre pre part.
Hi Salas!
I have an original La Maison de L'Audiophile schematics (1990) which is slightly different:
R9 = 2 kohms
No R11 for Jfet with Idss=2 mA (reccomended) but a 47ohms resistors may be added if you find only Jfet with Idss > 2mA
No R10
C5 = 1uF
Jfet was 1/2 2SK240GR


As far as tubes are concernd, I won't use an 12AX7 (not even a rare version) as I consider its sound not the very best.
Why not try other hi mu tubes such as ECC8010 or the much less expensive EC86? Or even a triode connected D3a.
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Old 20th February 2009, 12:30 AM   #1060
Salas is offline Salas  Greece
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If I will ever need one, I will make sure to simulate it with BL Idss. Thanks for the data. 6SL7 you like?
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