These amps should be "burned in" after about 20 hours of play time you will notice a smoother warmer sound. Your speakers could also be part of the problem. Raising the values of the V2 snubber caps will take some high end off the OD

I see you have turned your bass low.
Try this: Turn your volume(first pot on the left) up to 6-7.
Turn your presence all the way up. Adjust your tone controls to your likings.
Fine tune the presence.(set fairly high).

Hi
also try Level on 4 and ratio on 6. If you turn the amp up it sounds less buzzy

I bought it used, so I am assuming it should be burnt in. The cab I am using has a vintage 30 and a G12H30, which may be part of it, but the buzziness to the OD at higher levels seems to be there even threw other speakers. I'll have to look more into the snubber cap suggestion.

A few things from an admitted bit of a hack...but I am a tone snob.

Much of this has been mentioned and I may have missed the others.

1) Volume (far left) has to be 7ish or better.  It will fatten a single coil up.  Without it its kinda lackluster to me too.

2) Speakers?  I am using Celestion mixed pair G12H30 and Vintage 30 from Avatar.  Great bass response.

3)I tend to temper the presence a bit around midway or less

4)Guitar:I use Kinman AVN blues pups on my strat with a SD Pearly gates in the bridge with nickle 11s.

5) The Kleinulator or equivalent is essential.  It tames the beast and is part of that great tone.  I add a reverb and delay in the loop.

6)Settings: If it sounds thin to you go more bass.  Mine is 6 to 7 with a Strat and 5ish on the treble.  I am using the bright switch up and rock on with the fat switch off.  Bright switches on on Kleinulator.  The tone is very sweet...clean is better, however.  I think this is a good amp for a Strat but you have to drive the volume  on the guitar to collect the OD.  Otherwist the single coils don't speak loudly enough.  I ALSO TURN THE INTERNAL GAIN UP TO AROUND NOON TO 1 O'CLOCK...Nik put an outside adjustment for me.  Admittedly it goes Vintage Marshall or similar in tone but that ain't a bad thing!

7) Now, having said all that...Personally I think the OD is better with an LP.  To me anyway.  I prefer the Strat cleans though.


Casken

I tried this -
volume 6
presence - full
started with BMT all at noon.
bright off (I can't imagine a case where this is even needed!) deep off rock on
have the ratio/level at 3
master at 2

still way to much sizzle - even with the presence off it is way bright and the OD seems sizzly/fizzly, bass is farty. Lower bass to 2, still not good.

Hi,

I thought the same way when I got the amp 1,5 years ago -  too bright and too much gain in the lead channel. The first thing I did was to turn the internal trimmer to 9:30 (clockwise)

For the first month I tried to get used to the controls, which effect the sound in very different way compared to typical old-school guitar amps. After a few months the sound got much much softer.  Of course I also learned how to use the amp...

After about one year of regular use I knew what I liked and what I didn't like in the amp. The lead channel was too bright to my taste, I compensated it always from my guitar while soloing. Then I decided to make the snubber mod, which tamed the highs nicely. I also turned the internal trimmer to 10-ish.

What you are describing makes me think, that the amp has not seen much use. Perhaps the former owner did not have the patience to "burn it in" and just passed the thing on?

In my opinion, the most important control in this amp (after the rock-jazz switch) is the volume, which affects a lot to the behavior of the rest of the controls. With single-coils, you should be able to open up the volume to 7-8 and still dial in great clean tone.  Then just start experimenting with the overdrive settings.

I have pretty bright-sounding cab (V30 & Celestion Century), but I'm getting great cleans and smooth lead tones with OTS - with both humbuckers and single coils. My only complaint is that the volume jump between clean and overdrive is not big enough with some preamp settings (even with ratio dimed).