Posted by Matt5104 [ 81.153.48.157 ] on July 05, 2005 at 05:20:15:

Hi, I have a JTM612 with 2 12AX7s, 1 12AX7EH and 1 marshall ECC83 in the pre-amp. I'm considering replacing them all with mullard ECC83s. Can I literally just replace them and power up the amp, or do I need to re-bias the amp? Also, does anyone know the best order in which to place the original valves in the pre-amp? I've heard that putting the 12AX7EH in V1 (first valve position from right to left) is best, but i'm not really sure! Thanks very much.

Replies:

• Re: JTM pre-amp valves - Damir 16:56:19 07/07/05 (2)
  • Re: JTM pre-amp valves - Thermionic 10:24:03 07/12/05 (1)
    • Re: JTM pre-amp valves - Damir 14:50:02 07/12/05 (0)