Traynor amp- OT Tranny Specs

[pbman1953]

I'm still working this Traynor YBA-3A along with Ed's help.


The OT marked :
DB2B
A1332
9405, and the is a circled H next to this number.


When I Google any of the numbers ,  the A1332 goes to the Hammond site, but I can't seem to find that number.


By chance has anyone seen these before and know the specs.


Thanks

[Willabe]

I'm going to post some info here on a few Traynor amps as there's 2 different threads on 2 different Traynor bass amps.

From Kevin O'Connors TUT3, Bass Master, chapter 13, 13 pages. (With Traynor's schematic and Kevin's  'improved' clone schematic and Kevin's full layout drawing, but no measurements on layout.);

"The bass amp heads were the Bass Master YBA-1 and YBA-1A, 40w and 80w respectively, and the 160w Custom Special YBA-3."     

"..........YBA means Yorkville Bass Amp.  ....................  The number after the prefix is the model number. The "dash" numbers are further differentiation's within a family; the 'mark 2' versions take the letter "A" after the dash number."

"The YBA-1A is based on the stock Hammond transformer set of the 278X and 1650N, but custom versions were ordered and numbered differently........"

"Peter did fiddle slightly with the load impedance's between YBA-1 and the -1A, with the latter having a 4K3 aa load." (I don't see the specs for the iron set for the YBA-1, 40w.) 

He says, 40w YBA-1 operated (plate dcv?) at 420DCV, YBA-1A operated at 540DCV. And that at different times they could have come from the factory with 7027A's, EL34's or 6CA7's.

From Kevin O'Connors TUT3, Custom Special, chapter 14, 9 pages. (With Traynor's schematic and Kevin's  'improved' clone schematic and Kevin's full layout drawing, but no measurements on layout.);

He writes that for the 160w (4xEL34) YBA-3 Custom Special Traynor used the Hammond 278CX which is a higher plate current version and higher heater current of the 278X already being used in the 80w YBA-1A. And Traynor used the stock Hammond 1650T 120w full bandwidth OT with a 1K9 aa. This stock OT had Hammond's usual dual winding secondary with 5 leads. Traynor had this simplified to 3 leads for 2 Z taps, so custom ordered.

"The 1650T is just less than half the Z of the 165N, and in both cases, he also ordered his units without UL taps."

He writes, Traynor even built an even beefier version of this amp called the Super Custom Special, 250w into 2ohm or 4 ohm using 4X6KG6's/EL-509 TV (plate cap) sweep tubes.

I found this in a search from a bass amp web forum;               

"So here's the interior of an old Traynor YBA-4 Bass-Master that I had apart today to take chassis measurements for a rough brown/wheat grill 112 cab I'm having built for it.  It's a YBA-1 in a longer chassis mounted in a 115 bass combo cab.  Not many of these around."

[kagliostro]

Ciao Brad

Many thanks for sharing this documentation I'll store it in my archive 


Franco

[pbman1953]

Thanks for the info, so after reading this below I have a couple issues-




My transformer has 5 wires- Red ( power), Green & Brown (tubes) black & yellow (8ohm -speaker connections). When you say 2 z taps ,it seems that I missed out, I only have 1.
I wrote to London Power who helped give the tips for the 6550 upgrade for the YBA-3a. He told that there may be a hidden "green" wire tapped off under the board. I decided to pull off the OT, no extra wire.






 He writes that for the 160w (4xEL34) YBA-3 Custom Special Traynor used the Hammond 278CX which is a higher plate current version and higher heater current of the 278X already being used in the 80w YBA-1A. And Traynor used the stock Hammond 1650T 120w full bandwidth OT with a 1K9 aa. This stock OT had Hammond's usual dual winding secondary with 5 leads. Traynor had this simplified to 3 leads for 2 Z taps, so custom ordered.

[pbman1953]

I just went to the Hammond site to look up the 1650T. The spec is 15 lbs. Mine seems like 10-12.




1K9aa, what is this?

[sluckey]

1K9aa, what is this?

1900Ω plate to plate impedance

[pbman1953]

Yes, that points to the 1650t.
Thanks

[pbman1953]

After all the info that came in from the forum and Hammond, I bought on Ed's recommendation, a Heyboer OT.


I have to say I'm one happy camper!  Now I have exactly what I wanted, 4 & 8 ohm combination plus the stock transformer was a measly 9 lbs, after a true weigh up. The Heyboer is 12. The new one is almost as big as my PT.


I wrote about having issues with the KT- 120's in past reports and that was with the old OT. I can see now that the stock OT really didn't do well handling the Kt's. The stock OT would hum, just being on, but not with EL34's or 6650's. The Kt's need an upgraded OT. The amp now has scary transients, along side my Sunn 300T. Now these are just my observations, and I'm a novice compared to many of you.


So at this point I'd like to sell my Traynor (Hammond) because I don't want it as a back up. If I get another I'll just give Heyboer another call. If you know what this is worth please let me know and if anyone of you are interested let me know that too. I figure I'd offer it here first.


Thanks to all of you that have chimed in , Thanks!

[Ed_Chambley]

There is a place the post for sale items.  Keep in mind ANY large OT like this one are not a dime a dozen.  Just go with the price for the Hammond as your listing price and take offers.  Since it is Traynor spec someone wanting one for the amp you have may want it.


Traynors have not become collectable per say, but they will become so since they are true old amps without PCB boards.  I will say this, if the amp ever becomes very sought after you will wish you still had the transformer.


Oh, and I did not do anything but answer a couple of questions, you did the work.

[Ed_Chambley]

After all the info that came in from the forum and Hammond, I bought on Ed's recommendation, a Heyboer OT.


I have to say I'm one happy camper!  Now I have exactly what I wanted, 4 & 8 ohm combination plus the stock transformer was a measly 9 lbs, after a true weigh up. The Heyboer is 12. The new one is almost as big as my PT.


I wrote about having issues with the KT- 120's in past reports and that was with the old OT. I can see now that the stock OT really didn't do well handling the Kt's. The stock OT would hum, just being on, but not with EL34's or 6650's. The Kt's need an upgraded OT. The amp now has scary transients, along side my Sunn 300T. Now these are just my observations, and I'm a novice compared to many of you.


So at this point I'd like to sell my Traynor (Hammond) because I don't want it as a back up. If I get another I'll just give Heyboer another call. If you know what this is worth please let me know and if anyone of you are interested let me know that too. I figure I'd offer it here first.


Thanks to all of you that have chimed in , Thanks!

Rich, also let us say you purchased this Transformer for $60 shipped to your door.  That was more of a deciding factor for me.  I really like Hammond stuff, but hard to pass up on a deal like that.

[pbman1953]

Yes, it was a sweet deal, thanks to someone canceling an order. Not sure how old it was because it wasn't in a new condition. But that's ok, it's doing the job.  Plus , our friends in Canada call Heyboer, the Hammond of the USA.


True , I did the work, Ed, but you were still the sense'.

[Ed_Chambley]

Yes, it was a sweet deal, thanks to someone canceling an order. Not sure how old it was because it wasn't in a new condition. But that's ok, it's doing the job.  Plus , our friends in Canada call Heyboer, the Hammond of the USA.


True , I did the work, Ed, but you were still the sense'.

Well if it is old it should have a vintage tone.

[pbman1953]

True, But I notice that it's very similar to the stock, just with more balls.

[Danfrank]

Hi,
Sorry for the necropost but I bought a Traynor YBA-3A about 6 months ago and went through the whole amp to update the filter caps and I put on Speakon 1/4” combo jacks for the speaker outputs.
Anyway, I did take measurements of the output transformer and the primary impedance of the OT is 1050 ohms.
Closest thing that is currently made that’s off the shelf is the Hammond 1650W but all the impedances would have to be halved, so the primary becomes 950 ohms, the 4 ohm secondary becomes 2 ohms and the 8 ohm secondary becomes 4 ohms. The 1650W is around twice the size of the Hammond that was originally used in the YBA-3A but there is plenty of chassis space for it to fit.

[sluckey]

I did take measurements of the output transformer and the primary impedance of the OT is 1050 ohms.

How did you do that? Be specific.

[Danfrank]

Primary(sq)/secondary(sq)=turns ratio
Radiotron Designer’s Handbook has the formula.