Author Topic: Sunn 3-4PT  (Read 2980 times)

0 Members and 1 Guest are viewing this topic.

Offline David W. Smith

  • Jr. Member
  • **
  • Posts: 2
Sunn 3-4PT
« on: September 18, 2000, 08:12:00 pm »
Hi, I have a Sunn chassis that has a shorted power transformer 3-4PT. I would like to get a replacement. I see that the Torres website has a Hammond  30-40 Watt power transformer with 270-0-270 on the secondary. Has anyone had any experience with this one or any other companys PT as replacement for the Sunn?  The chassis is from a Sonaro bass amp and has a GZ34 rectifier and two EL34 power tubes. The transformer blows the fuse with nothing connected to it and gets quite warm in about three seconds. I have got the capacitors on order and checked all connections and resistors. I will be ready to go if I can get the proper power transformer and the output transformer is not shot as well. Thanks in advance. David  

Offline mike

  • Sr. Member
  • ****
  • Posts: 127
Sunn 3-4PT
« Reply #1 on: September 21, 2000, 10:21:00 pm »
Hey David, go immediately to http://www.triodeel.com and then go to their transformer page and look up Dynaco replacement transformers, perhaps the MQ-431-CL. You should be able to find an exact replacement(as you may or may not know, Sunn amps were based on Dynaco hifi amp designs). Their direct replacements should work much better than what Torres suggested. (FYI...there seems to be a bit of controversy regarding how Dan Torres fixes things--if you go to http://www.vintageguitar.com and check the "amplifiers" bulletin board you'll find a few people not too happy with the work he's done, however, I've learned quite a bit from his book, "Inside Tube Amps", so take it all with a grain of salt).  Also, take a little time to go through the triodeel site, there's alot of good stuff there, amusing links, etc. As far as that cabinet you're looking at is concerned(thanks for the direct email)that definitely would be a classic early Sunn cab(is it 11" deep or 15"?) --those speakers are probably JBL's, but I would still verify it. $399 is a little high...even with JBL's , I wouldn't pay more than maybe $275(but that's just me!)  Good luck, Mike