First Post! Background and need some guideance

[AudioGeek]

Hey everyone! Been a lurker here for a while. I have found that this forum has tons of useful information about design, tubes, guitar amps etc. A wealth of knowledge. Anyways, I have been interested in tube circuits for the last 20 years. I have built some Hifi amps (SE and PP) plus 3 guitar amps. All the guitar amps have been SE designs. Did a copy of a Supro super with 6SL7 tubes.. sounding very nice.

I have some ideas on the next project I want to do but need some help. It will be a small 8-10W amp that can play clean and really wail if needed.

1) EF86 -> 12AX7 CF -> Framus Mid / vol -> EF86 -> 12AX7 CF (or cold clipper) -> SE EL34

I know there is some gain I may need to reduce in this. Input stage I am thinking of running it with a really low screen voltage. I want to be able to swing that pentode fully with regular voltage input levels. DC couple the CF with a low resistance on the CF say 47K or something. Drive a Mid / Vol control into another EF86. This EF86 will have switchable NFB from running no bypass cap / bypass cap / full GFB from output.

Do I need the second CF? Should I instead put in a switchable 12AX7 cold clipper for the 2nd CF? Should I run the 2 EF86's with one hot and one cold? Run first one hot with low plate voltage, and run second cold? If second one is cold I may not be able to DC couple that second CF to it depending on the plate voltage of the EF86.

2) 12AX7 -> 12AX7 CF -> Framus Mid / vol -> EF86 -> SE EL34

Same as above but first 12AX7 a standard input stage, but with hot / cold / normal bias. Would this work into a DC coupled CF? I would need to see if the changes in the pentode plate voltage will affect the CF at all.

I do want to incorporate a pentode, if not 2 pentodes in the amp. Just don't know yet the direction I want to go. Of course there are tons of operating points I could use for the pentodes. I do want to drive them hard.

Thank you for any help! Please let me know what other information you may need.

[TUBEDUDE]

Are you settled on the EF86? I like the 5879 pentode. It was designed for audio, performs well and many great NOS examples are available for low money.

[AudioGeek]

not necessarily the EF86. I was trying to use tubes that are currently in production. But I am open to the 5879. I have also seen many examples using that tube.