Hi all, just cracked open my 6505 head I bought used a few days ago, planning on swapping the preamp tubes to the JJs and one Tung Sol that I already have.

Turns out the preamp tubes already in the head are 3 JJs and 2 Electro-Harmonix.

Just wondering what the best configuration would be? I now have 7 JJs, 1 Tung-Sol and 3 Electro-Harmonix preamp tubes.

I was planning on doing Tung-Sol in V1 and all the rest JJs... but as I now have 3 EHX ones that I didn't think I did it opens me up to more options.

Basically here is my tube rundown:

I have a 6505+ combo loaded with all ruby tubes (stock).

I swapped both the power and preamp tubes for JJs, and swapped out the V1 preamp for a Tung-Sol.

I have just bought a used 6505 head, and I am therefore selling the 6505+ combo.

I will be putting all the ruby tubes back into the combo so that when I sell it it is as stock.

I checked the back of the 6505 head and it has 3 JJs and 2 EHX preamps, and 4 ruby power tubes.

So, if we disregard the combo as I am selling it, this gives me

7 JJ preamp tubes
1 Tung-Sol preamp tube
3 EHX preamp tubes
2 JJ power tubes
4 ruby power tubes.

I am wondering what the best combination would be? If the EHX's are sh*t then I assume 4 JJs and the Tung-Sol in V1?

Also for the power tubes, I assume it wouldn't be a good idea to put my 2 practically new JJs in and keep 2 of the existing rubys in there?
How many tubes doesthe 6505 head have? My advice is load up the preamp with JJs and then try the tungsol in V1.

Not sure about mixig te power tubes like that though.

Itll be safe to put only the 2 JJs if theyre inthe 2 inner or 2 outer sockets and you change the impedance switchdown one selection. (8ohms would go down to 4, even if youre still running a 8 ohm cab)

Mixing both probably wont cause issues because the 6505 is probably boased super cold but ill let someone more knowledgable confirm that