Probably insufficient B+.
B+ MUST be equal or greater, than suspected anode voltage + half of required anode voltage swing + 20..30V headroom for CCS.
B+ MUST be equal or greater, than suspected anode voltage + half of required anode voltage swing + 20..30V headroom for CCS.
I don't understand how here https://www.mvaudiolabs.com/tubes/tube-data-library/4p1l/ can reach
Ia-35mA, Ia-600mA, -9.3V BIAS, 165Va?
While I wait the OPT for headphones just curious how it works as preamp.
N.B. to have 35mA Ia 620mA -9.3V Bias Va 185V
What's the anode voltage swing or how can calculate or measure?
N.B. to have 35mA Ia 620mA -9.3V Bias Va 185V
What's the anode voltage swing or how can calculate or measure?
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If you want to use CCS loaded tube as preamp output swing for example 6 Vpp -3V peek- (little over 2V RMS), the required B+:
Ua+Vp+20V (for CCS)
185V+3V+20V= 208V
For a little headroom use 220V as B+.
Ua+Vp+20V (for CCS)
185V+3V+20V= 208V
For a little headroom use 220V as B+.
Bela with Va 185V & CCS 41mA doesn't sounds good, music stutters and flaps. With Va 165V & CCS 23mA sounds without stutters and flaps. Now I will try Va 130V 9mA & let you know.
Va 130V CCS 9mA doesn't sound good the music flaps but no stutters surely need more B+ or more CCS or both.
It's very fun & time consuming and you have to be patient to find the sweet spot for the best sound quality.
Hmmm...
ATRA0211 at about -3dB 35Hz...10kHz?
In the middle of this page:
https://www.jogis-roehrenbude.de/Leserbriefe/Frank-Kneifel-PCL805-Amp/Kapitel 1.htm
ATRA0211 at about -3dB 35Hz...10kHz?
In the middle of this page:
https://www.jogis-roehrenbude.de/Leserbriefe/Frank-Kneifel-PCL805-Amp/Kapitel 1.htm
I'm very old and surely don't listen high frequency.
Price for 2 Toroidy TTG-EL84SE shipping incl. 222,34 EUR and are too big for my chassis. The price for the 2 ATRA0211shipping incl. 100€00!
Price for 2 Toroidy TTG-EL84SE shipping incl. 222,34 EUR and are too big for my chassis. The price for the 2 ATRA0211shipping incl. 100€00!
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Sound is good, driver is 801A. Very good relation quality price, a lot better than Edcor.
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