Hello all,
Following this thread Traynor YBA-3 impedance rating and info (for posterity) , I’ve decided to open a new thread for this latest acquisition/resto.
Couldn’t help myself, wanted one for a while and I saw one in a local guitar shop being there for almost three years. I didn’t really got a deal but anyway!
It was announced as being a 1970 but upon email exchange with Yorkville/Traynor, it’s a 1969. Date codes on the cans indicates DEC 09 too.
First tests showed no hum, scratchy switches and annoying crackling/popping.
Three prongs conversion already done, good.
After two weeks sitting gathering dust on my bench, I’ve completed all what’s needed yesterday evening:
- all filter caps were replaced with two times 2x180uf@450v in series, reusing the original 100k’s balancing resistors. Under the hood with some old clamps and zip ties;
- Illinois 100uf@450 filtering for the preamp/PI was replaced with a Xicon 100uf. The Illinois was probably there since the 90´s, so 30 years;
- the two 8uf bias caps got replaced;
- the two 250uf’s at V1 and V2 got swapped each for a 200uf paralleled with a 47uf. Hard to find value nowadays...;
- Deoxited all switches and pots;
- crackling/popping was cured by swapping V1 with another 12AX7 in my collection. Weird, as I tried previously two swap around the three original 12AX7’s but the problem remained. Probably that the two other ones don’t exhibit their noise in other positions (V2 and V3 PI);
- undocumented and short lived 1 Meg PI balance pot appears to be seized and stuck at the middle (500k on each side). Not sure, but it could also be that someone put a little circlip to block it... Anyway, I won’t bother. Not looking for high fidelity here...;
- precedent tech added a 10k bias pot: it was set at 85-90 ma for each pair! Yikes, talk about hot bias, almost 100 percent dissipation!! Got it dialed back at 53-55 for each pair, 60 percent with a plate voltage of 550vdc. Those JJ’s E34L did had a hard life but still test at 80-85 percent on my tube tester. Tough tubes!
I’m tinkering about the addition of a master volume as shown on the later version but I will try it as is for now.
Dead quiet, powerful and it was a breeze to bring in it up to specs technically wise. One evening of work, thanks Mr Traynor for the simple layout!
It’ll go back in its cabinet today and will be paired with my Ampeg SVT-210AV bass cab. The SVT-210AV was paired with my V4 but someone local built me a 2x12 cab for the two Basslite’s S2012 remaining from my YGL-3 combo project.
Patrice
Following this thread Traynor YBA-3 impedance rating and info (for posterity) , I’ve decided to open a new thread for this latest acquisition/resto.
Couldn’t help myself, wanted one for a while and I saw one in a local guitar shop being there for almost three years. I didn’t really got a deal but anyway!
It was announced as being a 1970 but upon email exchange with Yorkville/Traynor, it’s a 1969. Date codes on the cans indicates DEC 09 too.
First tests showed no hum, scratchy switches and annoying crackling/popping.
Three prongs conversion already done, good.
After two weeks sitting gathering dust on my bench, I’ve completed all what’s needed yesterday evening:
- all filter caps were replaced with two times 2x180uf@450v in series, reusing the original 100k’s balancing resistors. Under the hood with some old clamps and zip ties;
- Illinois 100uf@450 filtering for the preamp/PI was replaced with a Xicon 100uf. The Illinois was probably there since the 90´s, so 30 years;
- the two 8uf bias caps got replaced;
- the two 250uf’s at V1 and V2 got swapped each for a 200uf paralleled with a 47uf. Hard to find value nowadays...;
- Deoxited all switches and pots;
- crackling/popping was cured by swapping V1 with another 12AX7 in my collection. Weird, as I tried previously two swap around the three original 12AX7’s but the problem remained. Probably that the two other ones don’t exhibit their noise in other positions (V2 and V3 PI);
- undocumented and short lived 1 Meg PI balance pot appears to be seized and stuck at the middle (500k on each side). Not sure, but it could also be that someone put a little circlip to block it... Anyway, I won’t bother. Not looking for high fidelity here...;
- precedent tech added a 10k bias pot: it was set at 85-90 ma for each pair! Yikes, talk about hot bias, almost 100 percent dissipation!! Got it dialed back at 53-55 for each pair, 60 percent with a plate voltage of 550vdc. Those JJ’s E34L did had a hard life but still test at 80-85 percent on my tube tester. Tough tubes!
I’m tinkering about the addition of a master volume as shown on the later version but I will try it as is for now.
Dead quiet, powerful and it was a breeze to bring in it up to specs technically wise. One evening of work, thanks Mr Traynor for the simple layout!
It’ll go back in its cabinet today and will be paired with my Ampeg SVT-210AV bass cab. The SVT-210AV was paired with my V4 but someone local built me a 2x12 cab for the two Basslite’s S2012 remaining from my YGL-3 combo project.
Patrice
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