Traynor YBA200-2 Mods: Advise please

[M. Owen Santy]

Hi folks:

Just switched my gear back to Traynor/Yorkville after a few years away. Love the tone, but I am lacking a bit of clean headroom.


To that end, I'm looking at re-tubing the whole thing. Would like suggestions for EXACT types/brands to achieve more clean headroom and allow a bit more volume. Current Config is two 12AX7 pre-amp tubes, a 12AU7 phase-splitter, and four KT88 power output tubes. (thinking switch to 12AT7 ?)


I'm also wondering if a change to Speakon jacks would help - I would thing that they would offer a bit more conductivity to the cabs. (using a 2x10 & 1x15 - both 8ohm)


If anyone has experience with these or could suggest any other modifications I would appreciate it. Have always played with stock equipment. Have seen snippits on the web saying that this is a very easy amp to mod - just cant easily find specific specs.

Thanks in advance!

[Downunderwonder]

Unless I'm very much mistaken you can't stay clean as long if you drop the preamp gain. You have to wind up the master vol to compensate. Maybe other output tubes break up later than KT88? Next stop YBA300.

[Mr. Foxen]

different tubes are going to make a minimal amount of difference to your headroom, only big change can be if you have a duff valve that is breaking up early. changing pre valve types is basically going to do the same as turning the knobs aside from some places it will mess with your eq centres due to difference plate resistances and such. Upping the filter cap values might give some more headroom, depends what is in there.

[M. Owen Santy]

All filter caps are going too - part of the process of changing out the tubes (IMHO anyway - if you are going to do it, do it all)

[pgk]

the obvious thing is to always keep your master wide open, pretend it isn't even there. the only readily available tube that has more clean headroom than a KT88 is a 6550, even though a KT88 can pump out more power per pair. a 6550 won't start distorting until you're up around 7 or 8 at the dial, because they're designed to not give up the ghost until they're almost out of steam. no you won't get any more power, but you should get more clean headroom within the amp's power range. plus a 6550 has huge lows. myself i'd leave the KT88's in place. definitely change out the first 12AX7 to either a 5751 or a 12AY7. if you Really want to go nuts (and if you have a GREAT tech) have him or her install a HiWatt style phase inverter circuit, which requires installing one more preamp tube socket for it to work. it's the most efficient phase inverter circuit of them all, save for a Fender 400PS. here's a great primer for maximizing headroom in any tube amp, and good luck to youhttp://www.aikenamps.com/BlockingDistortion.html

[Mr. Foxen]

All that stuff depends on the circuit, not the valve. You can run more power cleaner from a KT88 that a 6550, in a circuit designed to do so, because they all round handle more. And pretty sure this amp is built round KT88, so wrong valves pretty much will only increase distortion (a lot of modern KT88 are 6550 in a different bottle though)And numbers on a dial never meant anything.

[BassmanPaul]

If the amp was designed for a 12AU7 it could well be that there is a good reason for that choice. Depending where the bias to the output stage is inserted by changing a driver tube you could well destabilize the entire amp.

[MAMMOTHvolume]

Originally Posted by pgk

the obvious thing is to always keep your master wide open, pretend it isn't even there. the only readily available tube that has more clean headroom than a KT88 is a 6550, even though a KT88 can pump out more power per pair. a 6550 won't start distorting until you're up around 7 or 8 at the dial, because they're designed to not give up the ghost until they're almost out of steam. no you won't get any more power, but you should get more clean headroom within the amp's power range. plus a 6550 has huge lows. myself i'd leave the KT88's in place. definitely change out the first 12AX7 to either a 5751 or a 12AY7. if you Really want to go nuts (and if you have a GREAT tech) have him or her install a HiWatt style phase inverter circuit, which requires installing one more preamp tube socket for it to work. it's the most efficient phase inverter circuit of them all, save for a Fender 400PS. here's a great primer for maximizing headroom in any tube amp, and good luck to youhttp://www.aikenamps.com/BlockingDistortion.html

Your post confuses me, 6550s in that amp will melt, 6550's don't break up later or have more headroom, they'll do the same power as the kt88's if they stand the voltage.

The hiwatt splitter isn't that great. The one in the amp atm is far superior.

Blocking distortion is a very different thing

[robd]

I had an EH 12AT7 in the V1 slot in mine, and it enabled the amp to get more volume before breaking up

[Tuned]

A 12AT7 as the first valve shouldn't help, it's the second where break-up will occur first. 12AT7's handle more juice without distortion, but have less gain so you'll have to turn up a bit. The power tubes shouldn't break up so easy, and I doubt a modern Traynor amp can last long driving the power tubes that hard. (Sorry, I love Traynor but they don't make them like they used to)

Speakon jacks won't make a significant improvement. Like mentioned above, crank the master volume and bring up the input gain.

[M. Owen Santy]

Spoke with several amp technicians before doing this - and was a HUGE change. Headroom for Days!!!

Traynor YBA200-2 head has been hot-rodded from stock valves to US JAN nos 5751's in the preamp, Genalex 12au7 Gold Lion phase inverter and Genalex KT88 Gold Lion Power Tube "Soft" Quartet. Also has had the 1/4" output jacks changed to 4-wire Speakons.

They are Russian tubes, but they are fantastic at getting wicked clean headroom. Very hi-fi while retaining the warmth of a tube head. Tone is absolutely amazing thru the Wizard 4x10's I use on stage. Reminds me of cleaner tones from an Eden WTB300V.

Definitely recommend these mods to other Traynor YBA200 owners - big fat change from the stock Marshall style gain structure on a head @ 1/3 the cost!

[rodl2005]

Great to hear, congrats.:thumbup:
I wonder if my YBA300 would benefit from the same-sorta.
I ain't complaining about it's tone/headroom now, but it's food for thought

[bb5000]

I checked the schematics for YBA-200-2, it seems that it's operating the KT88's at a plate voltage of 565V. Compare it to ~700V in the Hiwatt DR201, for example.
Filtering is 235 uF in the first stage (2x470uF in series), but the following filter stages are ~10 uF, which seems a bit low.

The Hiwatt phase inverter was mentioned, the interesting thing with that is that it uses a regulated DC voltage to set the bias for the LTP PI, that's fixed bias instead of cathode bias, which should give it more stability. The 400W Hiwatt had an extra CF stage after the PI as well to be able to drive the 6xKT88's more efficiently.

[M. Owen Santy]

Originally Posted by bb5000

I checked the schematics for YBA-200-2, it seems that it's operating the KT88's at a plate voltage of 565V. Compare it to ~700V in the Hiwatt DR201, for example.
Filtering is 235 uF in the first stage (2x470uF in series), but the following filter stages are ~10 uF, which seems a bit low.

The Hiwatt phase inverter was mentioned, the interesting thing with that is that it uses a regulated DC voltage to set the bias for the LTP PI, that's fixed bias instead of cathode bias, which should give it more stability. The 400W Hiwatt had an extra CF stage after the PI as well to be able to drive the 6xKT88's more efficiently.

Now wondering if my next mod would be to get hold of a YBA300 (or equivalent) output transformer, power supply/regulator and add a third set of KT88's. If could be done imagine would be a real monster as it does have a more "Marshall" like gain signature then the stock YBA300.

God I love tinkering!

Anyone got a clue on how this would work?

[BassmanPaul]

Good grief! If you go through this amount of work it would have been cheaper just to buy the 300 in the first place!!! Please be careful not to kill yourself while "tinkering"! Many have.

[M. Owen Santy]

Originally Posted by BassmanPaul

Good grief! If you go through this amount of work it would have been cheaper just to buy the 300 in the first place!!! Please be careful not to kill yourself while "tinkering"! Many have.

*Chuckle* Perhaps - but I would have been changing the tubes in that bitch to get exactly what I wanted out of it too. I'm a tweaker @ heart, and find that most amps come with crap for valves. The more you invest in getting YOUR sound out of any piece of gear is time and $ well spent IMHO.

Got this for $550 used. Great price.

[Nashrakh]

Originally Posted by SpectorErector

Traynor YBA200-2 head has been hot-rodded from stock valves to US JAN nos 5751's in the preamp, Genalex 12au7 Gold Lion phase inverter and Genalex KT88 Gold Lion Power Tube "Soft" Quartet. Also has had the 1/4" output jacks changed to 4-wire Speakons.

I still use the original KT88 because I'm broke but that's definitely something I gotta try (and somewhere down the road I guess it's even necessary)

On mine I didn't change the phase inverter tube. Does it make a difference in sound? I was under the impression it was negligible so I still have the stock tube in there. Would be a cheap mod though if there's some effect.

[M. Owen Santy]

Originally Posted by Nashrakh

I still use the original KT88 because I'm broke but that's definitely something I gotta try (and somewhere down the road I guess it's even necessary)

On mine I didn't change the phase inverter tube. Does it make a difference in sound? I was under the impression it was negligible so I still have the stock tube in there. Would be a cheap mod though if there's some effect.

I knew what I wanted for pre-amp & power tubes and figured while I was in there anyway, might as well upgrade to a great quality phase tube while I was at it.

All I can say is that the head is sweet as honey now.