I change R1 to set the current before 1Ω for 0.5Ω to reach the 1A setting, measurement check was 0.582V across 0.5Ω = 1.164A enough for the 5687 heaters, I set the filaments voltage to 6.1V to starve.
Now time to listening before an LT1084 IC voltage regulator.
Now time to listening before an LT1084 IC voltage regulator.
All set to go then 
(Don't forget to check the heater line with the scope for noise. Lytic cap direct on the heater pins can help if picking noise).
(Don't forget to check the heater line with the scope for noise. Lytic cap direct on the heater pins can help if picking noise).
Listening session with success, very very quiet, no noise, low level micro information now can listen without difficulty also no signs of compression when the music reach high sound pressure, sound more like the reality more near timbre / tone of instruments.
The Valve Itch has cathode lifting voltage divider provision for the upper stage tubes also that you must apply. When not forgetting this, you can use it.
Improved the sound a lot in mine headphone amp 5687 triode OPT loaded 15K600 Edcor with measured output impedance 196Ω Sennheiser HD600.
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I'm really impressed with your work, mine friend Jordi aka JOIMONF diyaudio member here (done lately your Salas DCG3 preamp (line & headphone) told me UltraBib better than BiB and for me the BiB it's superb.
Changed 10.000uF for two 4.700uF BG in parallel used with 3 pins IC regulator previously WOW!!!!
Can go to 2.200uF for C101-301 in place of 1.000uF?
Can go to 2.200uF for C101-301 in place of 1.000uF?
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From 220uF to 1000uF has been tested on C101-301. Because its the Vref filter capacitor it cuts more noise closer and closer to zero Hz with more value. Going bigger and bigger value effects are: Diminishing noise filtering returns, lengthening slow start time to reach Vout, killing semis around it easier with bigger discharge in case of a mishap.
That's perfect, I have some BG 220uF, thank you.
I measured the trimmer: 495Ω for 6.1Vout so I'm looking for a fixed value resistor like Shinkoh or similar.
Any other position where increase the SQ changing to a better component?
I measured the trimmer: 495Ω for 6.1Vout so I'm looking for a fixed value resistor like Shinkoh or similar.
Any other position where increase the SQ changing to a better component?
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