Traynor YBA-1 the saga continues!

[guittech]

Hey Guys, well, while we were away with site troubles I messed around with YBA1 project a little more. The B+ is a little lower and happier, and I essentially made a JTM50 out of it... and i wasn't 100% impressed. so i changed it out to a JTM45 with el34's. and I wasn't 100% impressed, so I switched it out to kt66's.... and I was still a little "meh"

So now it's currently sitting as a low power tweed twin/Bassman with kt66's and I do happen to like it a little more.

I think I don't like "crunch" at least when I play with it. Maybe it's my 80's metal roots, but I tend to like SUPER distorted, or very clean. Degrees between the 2 don't usually do it for me. I've heard some amazing clips of other people rocking out with lower gain, but for me it seems to be super clean or super distorted.... Maybe my brain/ears are defective!

Anyways, so it's currently a tweed-ey circuit.... The wiring still needs some clean up, and I need to do some "housekeeping" but I usually wait until I decide on a final circuit before i get too critical with placement and lead dress.

[Stevem]

I am scratching my head here, you built it up so far as three different amps that can not do metal all on there own, yet that's what your preference is!

[guittech]

I didn't build it as a metal amp because i already have a few of those... I have a hotrodded JCM800 50 watter that sounds HUGE and A Mesa Boogie Stiletto Ace Head. So I am all up on "metal Heads" lol

I have a couple of Matchless based amps (Badcat Judah and DC-15 watt clone from Ceriatone) and I still have a DrZ Maz8 and a Traynor Bassmate that has been modded to a more deluxe-ish vibe.

I also have a Princeton HP chassis from Weber with a set of way oversized iron from Allen Amps that is going to be a TW or Marshall combo... depending on what i decide on later.

AND i still have a big ass chassis to put something silly in...

So yeah, I don't NEED a metal amp... or any amp really, I also have a few little goofy bits and pieces floating around. (H&K Tubemeister, some bass amps)

As i said, I like HEAVY gain, and CLEAN CLEAN CLEAN... I do like a little warmth on my cleans, but for the most part, VERY clean amps for when i play clean.

Did i mention Clean?

lol

I really like the traynor as a low power tweed inspired amp... with 12ay7's in the preamp.

[guittech]

Yet more Traynor-ey developments!

So, I decided to try a 12at7 in the Phase inverter. I know from countless threads that it is a Love or Hate it type of thing. I switched it in and loved it! Even tried a 12ax7 in the v1 position again and loved it even more! My only problem is the brightness... I have a hate on for the top end sometimes, and this amp finally sounds "good" when i am driving it hard (occasionally with a pedal) Mids and bass cranked, treble and presence on zero. and the driver pedal i am using (left foot driver) has the tone control on zero as well. The distortion pedal i like (Diamond Fireburst) has the bass at half and the treble at zero as well... Don't know what it is, but i find all that high frequency annoying. My main Marshall type head of course has a vox cut control, so i will most likely switch the presence control here to a cut. since if i turn it past 2 the amp makes my ears unhappy.

So now it's a kinda bastardized JTM45 with a 12at7 PI. It's getting there.

Only other problem i am experiencing is that the "bright" channel is quieter than the normal... (yes even with the treble turned back up!) The bright channel on 5 is like the normal channel on 2. I am thinking that maybe my pair of mixing resistors are a little gamey, they are from the "junk drawer" in my shop.

[sliberty]

I am a big fan of the 12AY7 in the PI of some amps. Its cool that it helped here. Might also try 5751 in V1 and see what you think.

I know you have modded this amp, so what I am about to say might not be relevant, unless your mods where not all encompassing.

The YBA1 went through several iterations. The one I had was essentially a JTM45 with some different value components. A slightly later model was essentially a Plexi. As you would imagine, the Plexi-ish version of the amp was quite bright. So, you have one of those, and if there is any of the old circuit left, you, might look at doing a few more alterations to take it further from those bright Plexi roots.You could also compare values with other similar amps, like a 59 Bassman, etc. and see if there are any hints on what else you could mod to tweak the highs a bit.

if you do make any additional circuit mods, I'd recommend going back to all 12AX7's first, and then working your way back to the lower gain tubes gradually. More mods might just make the amp sound the way you like it without giving up the gain. But if not, you can always migrate back to the low gain tubes after you know.

[guittech]

Yeah, this is/was a later version, it had some bad parts, and iffy previous work, so i ended up doing a major rebuild. Circuit wise it's a JTM45, though it would have been closer to a plexi before. Switched all the caps, rebuilt the power supply, dropped the B+ down to 70's Marshall levels (YBA-1's run hot!) Aside from a tube recto and a choke, it's pretty much JTM45-ish now. with all Vitamin T oil filled caps. That did help roll off some of the treble, but this is more about my tastes than amp problems. My buddy who has good taste likes the amp as it is and wants me to quit messing with it... but as some of you know IT'S NEVER DONE!

Now that I am getting into the home stretch with this one, I need to test it on a few other cabinets. I've been using a closed back 1x12 speaker (a Suhr Badger combo cab with a sealed back and a Celestion Vintage 30) I want to try it with a 4-12 before i call it "done" since i use one occasionally... and Dr.Z ported 2x12.

[guittech]

I need to order a few odds and ends, so I may order a 5751 to try in V1. Always wanted to try one, but never had one around to test with.

Might order some slightly larger caps to try as a fizz cap post PI. I am using a 47pf there, i tried a 120pf and it was too much roll off, maybe something around 70pf might give me the sound i want without going too crazy.

[sliberty]

In the mean time, if you have another small cap, parallel it with the 47pF. For example, a 22pF parallel with a 47pF will give you 69pF. Then you can decide what you like. You would even use more than 2 if you don't have the values you need.

[guittech]

smalles have is 47.... i have 47s and 120s... I guess i could parallel a pair of 47's that are IN SERIES with a 47 that isn't.....

[gui_tarzan]

Or you could run a pair of 120s in series and have 60.

[guittech]

OKay, got a chance to mess around this morning.

When i tested all the other values of fizz cap, It had been with the old preamp, since i switched everything to JTM45 spec, everything has changed! So i started messing around with fizz caps, and got all the way to 1000pf... still not "it"

so i decided to build a preset "Cut Control" and insert it. After much testing, I have a .002 cap, and a 27k resistor. It rolls off just enough of the high end with the current setup, I am actually using the treble and Presence now (though the presence is still on one, and the treble creeps up to 3-4)

As I've said before, i am in the home stretch with this one i think. Even had to turn the tone control on my overdrive pedal to 3 or 4! Sounds GREAT for crunch with the 12ax7 now, but is has lost a little of That loving feeling with the 12ay7.

NOW. To tackle my other issues. I want to add some shielded runs to get rid of the little bit of hiss i get. Also I got some 1 meg pots from what is essentially a junk shop, and I am suspecting they are WILDLY different in resistance value. The "bright" and normal channels are WAY different in volume, even with the bright cap removed! So I am going to order some PEC pots, and some good heavy guage shielded cable, and start tying up loose ends so to speak.

Since i am at work (and i work in a music store) I may take the head upstairs and try it out with a few Marshall cabs today to check it out with other speakers.

[Stevem]

Your not going to find any relef for hiss with by added sheilding.

[guittech]

hiss/hum/noise

I like to shield the run from the inputs to the first stage. Doesn't always do a lot, but I feel better about it.

Amp isn't excessively "hissy" or anything, just like to use shielded runs early in the preamp.

Turns out i had a bit of shielded wire left, and did that run. so I just need to get pots that aren't crap.