Converting a Traynor YBA-3 Custom to 6550/KT88

[pbman1953]

I'm possibly going to pickup a Traynor YBA 3 Custom soon. I've been reading that it's very easy mod to use 6550's or KT88's

Here's the map-


http://www.freeinfosociety.com/electronics/schematics/audio/traynor_customspecial_yba3c.pdf


There seem to be 3 versions, A,B & C. I won't know until I get it .

But here's a section from the Velvet Black site that has many of the Traynor mod discusions-

Original tube [complement] was three 12AX7s and four 6CA7s that I swapped for 6550s (very easy, just boost bias about ten volts in order to have 30ma idle) Original input resistor was 100k and I changed it for 5.6meg like my Ampeg.
 
 Thanks

[kagliostro]

If your Traynor will be a YBA-3A Custom

with 6KG6A tubes, for an easy replacement

I think you can consider to modify it for JJ EL509

http://lib.store.yahoo.net/lib/thetubestore/JJ-EL509-S.pdf

http://thetubestore.com/teslael509.html

Kagliostro

[pbman1953]

The tube you are refering to is for the YBA-3 A "Super" Custom which is a 250 watts amp


My question is about the YBA-3 A Custom a 120 watter. Cabinet wise they are almost identicle but not under the hood

Stock tube is a 6CA7



Thanks

[kagliostro]

There seem to be 3 versions, A,B & C. I won't know until I get it

I was confused by reading the above mentioned

I assumed there was only one YBA-3A amp (and that the YBA-3A use 6KG6A tubes)

Sorry for the confusion

Kagliostro

[pbman1953]

Traynor called 2 high power bass model with both the sample model name, One as a Custom and the other as a Custom Super

[PRR]

> Stock tube is a 6CA7

6CA7 is a USA-marked EL34.

The amp is in-spec for EL34. High-quality guitar-rated EL34 are readily available at good prices, such as here.

While I generally approve of 6550 in HEAVY work, 60W-65W/pair is not too excessive for good EL34. In this range, 6550 will not make more Watts, and may max-out a bit harsher than soft EL34. In heavy use you may be replacing EL34 every few years, 6550 may give a few more years, but the price difference makes the cost/gig about the same (and less than you pay for shirts or strings).

[Jazzbass_5]

I'm possibly going to pickup a Traynor YBA 3 Custom soon. I've been reading that it's very easy mod to use 6550's or KT88's

Here's the map-


http://www.freeinfosociety.com/electronics/schematics/audio/traynor_customspecial_yba3c.pdf


There seem to be 3 versions, A,B & C. I won't know until I get it .

But here's a section from the Velvet Black site that has many of the Traynor mod discusions-

Original tube [complement] was three 12AX7s and four 6CA7s that I swapped for 6550s (very easy, just boost bias about ten volts in order to have 30ma idle) Original input resistor was 100k and I changed it for 5.6meg like my Ampeg.
 
 Thanks

I know this is an Old Post but I have a yba 3 custom special that I would like to do the 6550 mod to and the links you have posted are no longer valid.
Did you I happen to save them anywhere?.