1987 Marshall silver jubilee tube change
- Thread starter jonl
- Start date
A Jube comes with EL-34's stock.
Got a pic of your circuit board ?
Got a pic of your circuit board ?
EL-34 is a power Pentode.
6550 is a beam Tetrode, they're not interchangeable without minor resistor tweaks.
A pic of you main circuit board would help.
6550 is a beam Tetrode, they're not interchangeable without minor resistor tweaks.
A pic of you main circuit board would help.
Racerxrated
Well-known member
No. They came with EL34s, so if it has 6550s someone would have had to change the bias circuit to accommodate 6550s. You'll have to have a tech change it back. The new 2555x is different, you can run any octal power tubes in it with just a multimeter, no tech needed. Any combination of 2 pairs or a quad..2 EL34s/2 6550s, etc etc.