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Traynor YGM Tone Stack

Started by memoryman, July 30, 2015, 05:19:22 AM

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I have a Traynor YGM amp that has a Baxandall tone stack, which seems to be great for clean tones. I would like to change this feature as it is way too fizzy when it breaks up. What type of tone stack would give the YGM3 a "darker" tone? This is the YGM-4 version with (4) eight inch speakers.


I very much doubt a change or modification of tone circuit will fix the issue.
It's more likely the whole system tone that needs to be tweaked and that is no easy task.
If you can find a schematic of the Amplifier then post or link to it and we may be able to find a work around for you.

J M Fahey

Agree and add: *if*  the amp sounds fizzy on breakup, I guess you mean when it's used too loud and the power amp clips.

In that case the distortion is *after*  the tone controls and so is little affected by them.

I'd rather suspect the speakers, which have the final say on sound; what cabinet/speakers are you using?

As a side note, old tube amps and cabinets were designed to be used LOUD!! in an era with poor or no PA systems, so they were designed to be aggressive and cut through stage and untreated rooms mush.

At home or in a small rehearsal studio they may seem to be over aggressive, yet in a concrete or tiled basketball court or similar venue they perform well.

Anyway, google and post the schematic so we know what we are talking about.


schematic attached. 
There are 2 very common mods to darken these up a bit.
1)  If it doesn't have the bright switch, clip out the cap across the volume control.
2)  There is a "presence" cap in the PI circuit.  In the attached version, it is C11 in the PI area.  Remove it.
  Those are 2 quick easy things to try.

J M Fahey

Thanks for posting.

That ain't no Baxandall but some Traynor creation.

You can replace the whole volume and tone stack with one you like.
Fender/Marshall/Vox .
If you want fat, you can definitely use an Ampeg stack.

That said, if the amp on 10 is fizzy, it depends much more on the speakers, output transformer and output tubes, in that order.


Also don't forget that 10pf cap across the 3M3 resistor, (C8 on the schematic posted)

I would remove it as it makes one hell of a difference to hi-freq hash especially with EL84 valves as they are well known for sounding brittle if you give them too much bandwidth.



Thank all of you guys for your input. As per g1 and phatt I removed the capacitors that you mentioned and that definitely helped. :dbtu: I also am using a Weber MASS Attenuator which is working great.


I take it from the other posting,, re speaker change.
Just be aware the new 12 inch speaker will likely effect the tone more than you might be aware.
In which case you may find your tone tweaks will need rethinking as the Amp will likely be a little darker (less top end)
just thought I'd mention it, Phil. 


Here is a video of the amp after it was finished, I like it.https://www.youtube.com/watch?v=G69D5xxZHOo


Sounds good to me.  :dbtu: :dbtu:


That video was made with the volume at about 5 with an attenuator on very low (or high).The change from the stock 4'x8' speakers to an old Celestion 12', that coupled with the capacitor mods are dramatic.Now when the amp turned up enough to move some air it sounds a whole lot like an old Marshall. Very dynamic, it really nails those ever illusive "in between" sounds.