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>I am new to news groups so I do not know ifn what I posted ncan be seen. I have not seen it posted yet and I submitted it on 01/23/98. Can you help.
>I have just aquired a 1969 YBA1 amp and have been told that it can be turned into an amp similar in sound to a scream'in Marshall Plexi. Do you know where I could find a piont to point blue print of a Plexi or can you piont me to some one who might have already attempted this mod.
>Thanks DanO
the circuit in question is the '59 bassman circuit ... marshall copied that circuit in the plexi days ... the volume pots need to be changed to 1Meg and a few resistor and cap values in the tone stack and elsewhere need to be changed ... i think these are the changes you are talking about ... if you can locate a 5F8-A or 5F6-A Fender schematic compare your circuit and make appropriate changes ... send me a line if you need help
cheers, jc
\\\\ http://www.lynx.bc.ca/~jc/ \\\\\\\\\\\\\\\\\\\\\\
Traynor amp schematic archive, Vacuum tube Triode modeling
>Hi aaron/list ?!
>I'm not sure if the list is up and running yet so I thought I'd drop you (all?) a line to see how's it going ... btw, I've got another schematic on the page
Things are fine. I was expecting word from kraig and the go ahead to add all the names onto my copy of the list, and get it all up and running, but I haven't heard from him.
I'll have to check out the schematics. I've finally found someone to service my Traynor, and you can never have too many schematics!
I'm just trying to decide how to fit an IEC inlet to my YBA-1A. Is the amp vintge enough (1969) to worry about cutting a hole in the wood of the lower rear panel, or should I cut a new panel with the hole cut in, and retain the original?
From: "Aaron Turner"
--- Forwarded mail from kroger@ucla.edu
Hi, I'd like to know about your email list. Basically, I need to find out if the bassmaster YBA-1 (???) is the Traynor that is similar to a JTM 45and Tweed Bassman circuit, as I have a chance to get one. [For $150 I think - Aaron]
Thanks, Jim
---End of forwarded mail from kroger@ucla.edu -
I've heard that the YBA-1 is the same circuit as one of the Marshalls of it's era (60's to early 70's), but I'm not sure which model. Still, I'd recommend buying it (suprised?). The rhythm guitarist in my band got a convincing sound out of mine. They are a great amp - good components, especially the power transformer and very conservatively engineered, so they are reliable as hell. If it makes a sound it's worth the money. I guarantee that you will find some good tones in there. If you don't like it, contact me (kraigo@aol.com) and we can probably come to terms. I have two Bassmasters and if I see another for $150 or less I'll still buy it.
KO
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From: Aaron Turner[SMTP:aaron@minster.cs.york.ac.uk] Sent: Monday, March 09, 1998 10:04 AM To: aaron-traynor Subject: (Fwd) YBA-1 as Marshall JTM 45?
--- Forwarded mail from kroger@ucla.edu
Hi, I'd like to know about your email list. Basically, I need to find out if the bassmaster YBA-1 (???) is the Traynor that is similar to a JTM 45 and Tweed Bassman circuit, as I have a chance to get one. [For $150 I think - Aaron]
Thanks, Jim
---End of forwarded mail from kroger@ucla.edu
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From: jc@lynx.bc.ca X-Sender: jc@pop.lynx.bc.ca Mime-Version: 1.0 Date: Mon, 9 Mar 1998 14:51:05 -0800 To: aaron-traynor@minster.cs.york.ac.uk, kroger@ucla.edu X-LabelledFrom: jc@lynx.bc.ca (jc) Subject: Re: (Fwd) YBA-1 as Marshall JTM 45?
Hi kroger@ucla.edu (name, k or roger ?) ... and list
btw, could everyone who receives this email send me a quick reply so I know who's receiving this list-triggered-email so far (thanx!!)
>--- Forwarded mail from kroger@ucla.edu >>Hi, I'd like to know about your email list. Basically, I need to find out if the bassmaster YBA-1 (???) is the Traynor that is similar to a JTM 45 and Tweed Bassman circuit, as I have a chance to get one. [For $150 I think - >Aaron] >
>Thanks, >Jim
yes, it is almost-identical to the old Bassman (I had a modification list for that amp that doesn't deface it's original character - I'll put it up today) ... except Traynor had to change a few values so they wouldn't get sued by Fender ... in particular the volume pots are 4Meg which gives the circuits a slightly spungier attack (try this in a Fender or Marshall amp and it'll sound a bit more Traynorish) ... also the tone stack cap values is the other place the Traynor Bassmaster circuit differs from the Bassman/JTM45 ... Filter caps are notoriously poor in most Traynors anyway and need to be improved - either to improved-Fender values or stock-Marshall depending on degree of "Tweednessness" required (or Marshall ) ... the YBA1 ia a tinkerer's favorite, some will get pissed off here ... a few "careful" snips can bring this unit to it's utmost potential I believe ... still, stock it's nice enough for sure ...
... in my opinion the sixties Bassmasters sound quite better stock though the later ones are great/better (IMFO again) for extensive high-gain modding ... btwm you'll notice this $150 amp beats most boutique stuff, stick it next to a $2600 Rivera and make your comparisons ! ... in my mindthis beautiful sounding YBA-1 amp belongs up there with Tweeds, AC-30's and Marshalls for real natural guitar tones ... one of the best all-time amps ... yep, maybe I should shut up now ... :)
jc
From: kroger@ucla.edu X-Sender: kroger@pop.ben2.ucla.edu Mime-Version: 1.0 Date: Mon, 9 Mar 1998 16:53:12 -0800 To: jc@lynx.bc.ca Subject: Re: (Fwd) YBA-1 as Marshall JTM 45?
>Hi kroger@ucla.edu (name, k or roger ?) ... and list >
>btw, could everyone who receives this email send me a quick reply so I know >who's receiving this list-triggered-email so far (thanx!!) >
Got it, thanks for subscribing me. Also, thanks to everybody who responded with the great info, it's much appreciated. Is it true the YBA-1 came in an earlier version without fan and a later one with fan and extra trim? Are they the same inside re: circuit design, thus both can be modified (if desired) to be like a bassman/jtm45 in the same manner?
Thanks again, Jim
The early Bassmaster is Pete Traynor's version of the Fender 5F6/8-A ('58-'59 Bassman/Twin) circuit that Marshall suplicated in the JTM45 ('62) and stuck to somewhat thereafter ... both Traynor ('65) and Marshall introduce changes to the 5F6/8-A topolgy (Twin and Bassman are nearly identical topolgies) that distinguish them from the mother topology ... the Traynor version alters the volume pot values to a high 4Meg - this gives the preamp an overly spungy feel due to interaction with dynamic grid currents (players who find Traynors more wimpy should look into this) ... also like Marshall, the Traynor BassMaster output stage is slightly different in flavour and drive characteristics relative to the 5F6/8-A Fender circuit ... the BassMaster originally was running on 7027A's and later changed to EL34s, the BassMaster tranny is massive and appears quite reliable over time (Traynors amps were in general well enough built except that they were too heavy for most non-WWF civilians) ... like Marshall, so did Traynor also change a few components in the tone stack versus the 5F6-A tone stack (similar to Fender Blackface/Silverface values in fact) ... the early Bassmaster probably sports the best output tranny traynor ever used and is the main reason to play this piece (the same goes with all good amps obviously) ... the sound of the OT is not as glassy as that of a Marshall Plexi or many early Garnets(!) but it is nice enough that many players regard it as a magical guitar tube amp ... chicken knobbed that one ...