Using Telefunken EL-156 in Dynaco Mark III amp

[tubularfluxus]

I have two Telefunken EL-156 with these adapters to KT88 socket (1pcs EL156 Replace KT88 Tube Amplifier Socket Adapter Suzier B3 | eBay)

Can I use them in a Dynaco Mark III? How much mAh for tube should I bias them to?

 

[danFrank]

You can use them but they aren't going to give you more power in the Mark 3 setup unless you change the power transformer to get a higher B+.
On the plus side, the EL156 will be easier to drive than KT88s or 6550s.
The EL156 is rated for 50 watt plate dissipation.

 

[kstagger]

A few years ago I slapped in some Chinese EL156 tubes into my rebuilt Dynaco Mark IIIs. If I remember correctly I had to tie G3 to the cathode (pins 1 & 8) since the EL156 is a true pentode. Perhaps this is not an issue with the original Mark III circuit, but as I said this was a rebuild with all new sockets, boards, and hardware.