This new Air Duct works better than the bigger one....It directs the flow of air up and over the tubes more....I made one that moved the fan to the bottom of the duct....blowing the air directly up onto the tubes....While this cooled the tubes very well....it was very noisy....too noisy....Just need to make the duct out of wood now....I will post the measurements if anybody wants them....
I dropped the rear cover down to make a wider gap....Helps vent the hot air away from the amp....and also reduced the fan noise....
I have also been suffering with tube rattle....I put it down to the combos size or a bad tube....But when I was fitting the new air duct I noticed that the amps metal chassis was rubbing on the speakers metal frame....The speakers vibrations were traveling into the amps chassis and cursing the tubes to rattle....Not Good....I have glued some 2mm thick strips of rubber...."pond liner" onto the amps wooden chassis mounts to lift the chassis away from the speakers frame....No more annoying tube rattles....and yes I did try and shift the speaker down on their bolts but they were as low as they would go....the rubber strips were the best and easiest fix....
EVR-C30....still awesome....k.j.
Hey Keith,
ReplyDeleteI'm the proud owner of an EVR C30 and I have two questions for you (as you're my main source of info about this amp ;-) ).
First, the last time I've put a 12AX7 in V3, the vibrato channel stopped working. Can you please confirm your preamp tubes are V1 : 12AU7, V2 : 12AT7, V3 : 12AX7, V4 : 12AU7, V5 : 12AX7 ?
And then, is it easy to turn the fan around ? I've just replaced the 4x6V6s by 2xEL34s and the chassis became incredibly hot...
Thank you very much,
Guillaume