[Amps] Tube Cooling

[Roland AH6RR]

About 5 years ago I got a Dentron MLA-2500 with 1 bad tube and decided then
I wanted to convert it to the GI-7BT tube. I did all the mods except the air
box. I blew a tube from over heating (glad they were cheap I got 4 tubes for
75 bucks). I then put in another muffin fan on top of the amp to draw air
out and never had a problem with over heating after that. I picked the
GI-7BT because they are more robust and made for the tropics hence the "T".
In the MLA-2500 the original 8875 tubes had horizontal cooling fins with the
same plate dissipation as the GI-7B family and the single muffin fan did a
good job at cooling the 8875 but not enough for the cooler on the GI-7B. If
I did another GI-7BT amp I would use the air box and a single muffin fan. 

 

Roland AH6RR