I've been using my OTS for a couple of months now and in general I'm quite impressed with the overall sounds (Clean and OD).

By tweaking the internal trimmer down and varying my picking I've been able to get nice 'traditional D style' lead sounds - close enough for my liking anyway. If I crank things up a bit and pick harder, it screams as well.

However, there is one sound that absolutely sucks on my amp and that is 'popping the strings' when in OD.

If I do this in clean, it's great, nice and dynamic and tuneful, but in OD I get some really nasty harmonics that 'clash' for want of a better word almost to the extent that the harmonic is as loud as the fundamental note being plucked.

If anything the effect is worse at lower OD levels than higher and is present wherever I play the plucked note on the neck.

I've experimented with different valves in V2 including a nice NOS 5751 with no success and my OD trimmer measures 25K from wiper to ground (I am definitely not cranking the trimmer too high i.e it is at the 9 - 10 O'Clock position.

My thoughts are:

1. Power Supply to V2 possibly on the low side?

2. Perhaps I need to cut the bass response when  OD is engaged by changing a coupling cap value between before OD1 or between OD1 and OD2.

My guitar by the way is a Japanese Telecaster with Dimarzio Twang King and Chopper T pickups.

The amp was built by Ceriatone, no complaints other than this.

Just interested if anyone else has noticed the same thing?

Thanks Erwin

I did the heater wires a while back, that definitely improved the OD tone but that was before I discovered the issue with 'popping' the strings with my fingers when in OD.

If the problem was Phase Inveter related - why does my basic OD sound good? It's worth trying but I don't know how to adjuect Phase INverter (I'm guessing that you adjust for a 'balanced output'? Never done that before. I am using a 'balanced tube' in the PI position.

Filter Caps on the low side? Can you expand a bit more?

Thanks

Marc

Erwin

That's a really useful article and I think that it describes the sound that I'm hearing quite accurately.

Next question!!

Is sag designed into this circuit or have I got some capacitors that are out of spec?

My only doubt about whether it is sag is that I'm only playing at low volumes (1 - 1.5 on the master), I would have thought that sag would be more likely at higher volumes when the PSU is under more strain?

Does your OTS produce the same sound as mine when you 'pop the stings' in OD?

Were the jzucker mods that added 2 x 50 uF Caps designed to reduced sag? I need to see if these were fitted to my OTS although I bought mine after Nik adopted the mods, I need to check.

Erwin

Thanks for your input on this.

I've ordered a few extra caps to experiment with the power supply.

I'm going to add 2 x 50 uF in parallel with the 2 x 100 uF that are already there - understand the series / parallel calculation with caps being opposite to resistance.

I'm also going to experiment with increasing the 22uF caps to 30uF.

Thanks once again

Exocet

What voltage rating did you get?

I can only see 350 volt in axial.

Did you go for these or did you move to Radial format?