[kkqewl]

I recently acquired a Melody SP3 integrated tube amp and have spent the last 6 months rolling tubes in it. For the signal tubes I have settled on some NOS Sylvania 5751, Amperex 6922 and 12AU7s.

The best sounding power tubes I have tried are some older NOS 807s with adapters in place of the stock 5881 tubes. I know the 807 is a close equivalent to the 5881 but not exactly the same so I have two questions.

1) Are there any mods I can do the existing circuit that would be a better match for the 807 tubes in terms of sound and longevity etc.

2) Should I keep the bias level at 1.15 V as recommended for use with the 5881 or would I be better off at some other value for the 807s

I have attached the following schematics for the PS and main part of the amp.

Thanks in advance for any comments.