6P41s vs 7868

[huggygood]

No problem ,i have a space on the chassis

 

[jazbo8]

Make sure the filament windings can handle the extra current drawn by the added tubes, also note that the 6SN7's draw twice as much as the 12AX7's.

 

[huggygood]

Yes,thank's,i have many tdk lambda 12vdc in stock 😉

 

[huggygood]

just one question about the self of power supply .
what a amperage needed for this amp for the first and second self ?

 

[huggygood]

always looking for learning, I found this wonder on the net.
someone would have a constructive opinion on this scheme that I like a lot,
knowing that I have everything I need to build it with 7591s or 6p3Se 🙂

 

[jazbo8]

You have posted so many schematics, they are pretty much the same with little variations here and there. If you are going to use the original Rowe-Ami OPT's, they will dominate the sound anyway, so just pick a schematic and build it already... 🙂

 

[huggygood]

it's not for the AMI ,but for other amp with very very good 6k6 opt but very poor and bad schematic 🙂

 

[jazbo8]

Again, there's little difference between all the schematics posted in this thread, just variations on the same theme.

 

[huggygood]

ok,thanks 😉 🙂

 

[AmadeusMozart]

That's correct. I suspect that New Sensor could not conveniently source Novar bases, but Magnoval bases were available. The pin circle is the same, but Magnoval pins are bigger than Novar pins. Given the "tired" state of many units' sockets, the fatter pins can be a blessing. Be warned that once current production 7868s are used, going back to OS tubes, without replacing sockets, is not an option. Given the very, very, poor availability of OS 7868s, the socket issue is theoretical, not practical.



New Sensor will make the tubes, as long as a market exits. There are some units where installing Octal sockets and 7591s will not work, due to space considerations. Profit is a very powerful motive.

IMHO the EH 7868 is actually more based on the Brimar EL506 which is magnoval. The EL506 was a further development on the 7868.

EL506 @ The Valve Museum

I prefer the 7868 over the 7591(A) as imho it has better cooling. The bakelite Octal socket does not like the amount of heat the 7591(A) produces. And a tube cooler will work better on the 7868.


AM