Leak TL12 replica using 807s?

[SHiFTY]

I am thinking of building a stereo version of the Leak TL12, but using 807s instead of the triode-connected KT66, and 6SN7 instead of ECC33.

I have a couple of fire-engine red Mullard EF37A lying around, and some output transformers that should be ok.

Would this work, or would I be running the 807s too hard? Would I be better off connecting the outputs as ultralinear instead of triode?

Schematic
here

Anyone have experience with this amp? It seems to have a very good reputation! Thanks.

[EC8010]

I believe that Langford-Smith (He of RDH4) got away with making a Williamson using triode-strapped 807 instead of triode-strapped KT66, and the output stage conditions are virtually identical, so you should be OK. If you leave a little room around the output valves, you could always change later to KT66 if it proves necessary.

[fdegrove]

Hi,

Would this work, or would I be running the 807s too hard? Would I be better off connecting the outputs as ultralinear instead of triode?

Actually I've done this kind of work on a few Leaks already years ago.
While I left the input tubes in place (they last forever anyway) I changed the sockets of the KTs to UX5s and put in 807s in triode mode.

Worked straight away and sounded fine too us.

[316a]

Another alternative would be the loctal based 5B/255M which was designed (I believe) as a 'miniature' 807 replacement . This does not require a topcap and is another cheapie . Topcapped version is the even cheaper 5B/254M or 20V filament versions (5B/258m?) can be had dirt cheap . Only disadvantage is that ITT/STC were the only manufacturer , the 807 is more widely available and therefore cheaper

316a