are they mutually exclusive?

[iknowjohnny]

One thing i have realized playing around with power supply rails is that i always notice that higher UF values do indeed give a tighter sound, but it always causes the tone to sound thinner too. Is this an unfortunate tradeoff that has been fought since day one by designers, or is there a trick to get around it that i just haven't yet figured out?

[Jana]

I tend to use more than "normal" amounts of filtering and would not equate more filtering to a thinner sound. If anything, it is tighter with more punch and a solid low end. Some people like the mushy feel of marginal filtering, I like it tight. Neither, in my experience, is thinner sounding.

Speculation on my part, but it is possible that what you are experiencing as thinner is something that is present in your amp in either case but the mushy feel of less filtering is masking it.

[Zippy]

Do Trainwreck-style amps sound thin to you???

That's not my experience.

[iknowjohnny]

Speculation on my part, but it is possible that what you are experiencing as thinner is something that is present in your amp in either case but the mushy feel of less filtering is masking it.

maybe, tho i have to say this amp has been tweaked and changed in every imaginable way over the course of a year, and this is as fat as it's ever been. And it's been at times been several different marshalls ! So you could be right, but i haven't been able to make it any thicker even doing all the things i've been told over the last year. maybe our ears hear "thick" differently, i dunno. I'm not saying it's necassarily thin either way, just that it's thinnER sounding the more filtering i put in.

[John_P_WI]

+1 to Jana's comments.

The increase in filtering most likely has cleaned up the supply enough to eliminate some distortion artifacts. It is not necessarily "thinner", but is most likely "cleaner". More supply caps in parallel (especially if a poly is used) will also will seem faster due to the lower ESR of the caps paralled. There are ways around this if you want a more vintage feel.

John

[iknowjohnny]

There are ways around this if you want a more vintage feel.

Could you elaborate? i'd like to stiffen up the supply but don't want to lose the fatness. i have found a few ways, but anything more would help.

[John_P_WI]

Some of the easiest ways to keep the vintage feel is to add series resistance between the SS rectifiers and the first cap (whole amp will sag) or cap and center tap of the OT (power amp will sag) ect. These need to be flameproof power resistors etc and can be 10 to 100 ohm. Another trick is to add a small amount of resistance between the cathode of the electrolytic cap(s) and ground. Size to flavor.

Try Fred or UF diodes too for the SS rectifiers.

John

[iknowjohnny]

I've tried both of those. In fact, i just put down the iron after AB'ing a sag resistor about 10 times.(as i have done in the past....just can't seem to decide) But it's 180R. Is that too big? You said up to 100R so now i'm wondering. I find the tone gets too muddy and lacks chime when i use it. But now i'm wondering about trying less than 100. Don't have any that small tho in 30 watt or thereabouts.