NAD: Traynor YBA-3 Custom Special

[Stylee Mousse]

Having the mothership check it out sounds like a great idea.

random techs are not always the best. I remember taking my YBA 1-a to a guy nearby and when I picked it up he said “all done, I think you will really like the mods I did without asking you!”

 

[jazzbass_5]

I have my associates degree in electronics and I could easily change out the caps and add grounded power cord. I know a lot of people are in the camp of "if it ain't broke don't fix it" but I would rather replace the 51 year old paper caps and forgo a possible failure.

 

[Patrice B]

I have my associates degree in electronics and I could easily change out the caps and add grounded power cord. I know a lot of people are in the camp of "if it ain't broke don't fix it" but I would rather replace the 51 year old paper caps and forgo a possible failure.

When I got mine, I simply tested the tubes, cleaned the sockets and replaced power supply electrolytics. However, I had some intermittent gremlins so I’ve shotgunned the amp completely, until I found the culprit. At this point, half the resistors and all caps were replaced

I know, not the correct way to troubleshoot but now, I have a « brand new » YBA-3. No, I don’t believe in old caps mojo!

 

[Short4since64]

Having the mothership check it out sounds like a great idea.

random techs are not always the best. I remember taking my YBA 1-a to a guy nearby and when I picked it up he said “all done, I think you will really like the mods I did without asking you!”

Wasn't me! Probably modded 30 YBA-1s, a specific request for making incredible guitar heads from them. With the price new, duty at the bridge and the mod, still cheaper than a Marshall 50, sounded the same and rock solid reliable.

 

[Short4since64]

The YBA-3 was a proverbial brick shhthouse. Heavy iron OT which didn't saturate on low notes, they always worked, easy to service and sounded good. The PT in the early version could handle the added filament current to run a quad of KT88s which gave a cleaner sound and a little more balls (rebias needed). There was a later version which used transmitting tubes for outputs, never played one but understand that it was a monster.

 

[Stylee Mousse]

So luckily I was going to use my yba-1a for guitar, and have long enjoyed it through an open back 410. A very precise crunch machine for post punk, power pop etc.

hey Short, were you modding them to plexi like beasts? I recently did a fun experiment rigging up a classic metal sound with mine. (Although I’m not playing anything like that). My yba can def do jcm 800 and shades of Marshall major.

 

[jastacey]

There was a later version which used transmitting tubes for outputs, never played one but understand that it was a monster.

That was the YBA-3A, it used, if memory serves me, a quad of 6KG6, tubes, which were used in tube TV's, for the horizonal hold function , anyways, a story I read on the "Net", was Dan Armstrong ( He's the guy that invented, the plex glass guitars & basses, for Ampeg ), bought a YBA-3A and brought it to Ampeg, and a short time later the SVT came out, did they copy the power nodes of the YBA-3A, who knows?, but the YBA-3A is a pretty good amp, and is as rare, as hens teeth

 

[Patrice B]

The YBA-3 was a proverbial brick shhthouse. Heavy iron OT which didn't saturate on low notes, they always worked, easy to service and sounded good. The PT in the early version could handle the added filament current to run a quad of KT88s which gave a cleaner sound and a little more balls (rebias needed). There was a later version which used transmitting tubes for outputs, never played one but understand that it was a monster.

Not later but concurrent (or one year later or so) I would said (unless I am mistaken ). The rare as hens teeth YBA3-A with four 6KG6A’s for ~250 watts. Don’t know if it’s a rumor or if it’s true but it would had been the inspiration for the SVT?

EDIT***Ooops! Should had read @jastacey post before replying .

 

[Short4since64]

So luckily I was going to use my yba-1a for guitar, and have long enjoyed it through an open back 410. A very precise crunch machine for post punk, power pop etc.

hey Short, were you modding them to plexi like beasts? I recently did a fun experiment rigging up a classic metal sound with mine. (Although I’m not playing anything like that). My yba can def do jcm 800 and shades of Marshall major.

Basically, yes. 1K screen stoppers on the EL34s, small cap bypassing the cathode resistor of the 2nd 12AX7, tone stack capacitor changes. Cascade the input channels if the player wanted high gain (used a 12AY7 for the input stage in this case with a small cathode bypass) The YBA-1 mkII is very similar to a JTM45 with higher operating voltages and that mighty output transformer

 

[jastacey]

I might add, that Traynor built only about 200 or so of the YBA-3A's, and that is what I also read on the "Net", can't remember where I found that info, and on another note, a lot of the YBA-3's had a pair of surge protectors, built into them, they were problematic, meaning they would malfunction, causing loss of output, or a thin tinny sound, either way, they caused issues, they were usually grey tubes, but some were a bluish color, there was a service bulletin , and it said "just remove them", Look at the photo. I circled them in blue

 

[Patrice B]

I might add, that Traynor built only about 200 or so of the YBA-3A's, and that is what I also read on the "Net", can't remember where I found that info, and on another note, a lot of the YBA-3's had a pair of surge protectors, built into them, they were problematic, meaning they would malfunction, causing loss of output, or a thin tinny sound, either way, they caused issues, they were usually grey tubes, but some were a bluish color, there was a service bulletin , and it said "just remove them", Look at the photo. I circled them in blue
View attachment 5487360

They were fortunately absent (removed) in mine. They are Thyrectors (diodes?) BTW.

 

[jastacey]

Yes it is a Thyrector, it is a clamping device, what they did on the amps, they didn't recover, or reset, due to extreme voltage or long term heat damage, from being in an amp, the early ones weren't very good, here's a photo, of the location, removed from and amp

 

[Short4since64]

I might add, that Traynor built only about 200 or so of the YBA-3A's, and that is what I also read on the "Net", can't remember where I found that info, and on another note, a lot of the YBA-3's had a pair of surge protectors, built into them, they were problematic, meaning they would malfunction, causing loss of output, or a thin tinny sound, either way, they caused issues, they were usually grey tubes, but some were a bluish color, there was a service bulletin , and it said "just remove them", Look at the photo. I circled them in blue
View attachment 5487360

Those were present on all the YBAs. Intent was to prevent arc-over if the amp was run into an open circuit (CSA requirement? Reducing warranty claims?). I always just clip them out. If you plug a cable into the output but not into the cabinet expect to burn up your amp regardless of what protective device may have been installed.