Thanks hego, wasn't a mod, was my mistake.
That's the reason of less gain in the left channel.
Cheers
Felipe
That's the reason of less gain in the left channel.
Cheers
Felipe
As Hego said that explains the weird results you had before. Now that its solved how is gain matching going? Easier?
Tweaking the one I already have, now is going on with E283CC & 7N7 with 6SN7 socket adaptors for loctal sockets. Sound quality is very good.
7N7 are running to circa 6mA, could I push up to 9mA? if yes what resistors have I to change?
You have E283CC in Siemens only or other also like Mullard Philips Valvo?
They are running "by the book" as marked on the V1.2 schematic. But if you are curious for more mA I will have to check later for values because I don't have my design notes in this computer.
For sure. All tubes bought to Erno are super high quality, I have a pair ECC88 6922 Russian that sounds superb also I have two ECC81 EI long anode very good.
Try yourself out by parallelling 330 bias resistors. 2k, 1k... but dont push it to much over max plate dissipation 2,5 w.
Tubes in low noise high gain circuits differ sometimes a lot by sample for performance. Takes expert picking even among best suitable types for sure.
But what about R12? Its in the system and it will squeeze voltage allowance across sections as the mA go up. Need to progressively go lower to allow the same voltage as before.