The Amp Garage

Maybe I'm missing something but it would seem to me that the best way to set the OD trimmer is by listening and adjusting. Once you like what you hear you can measure it with the amp on or off for reference. I think this is a key point. Use the "measured values" things as guidelines, but only that....

Thanks, all.

Have you found the Alpha and PEC pots to both have smooth tapers, rather than stacked linear tapers?

Thanks, Tom. Yeah, nothing quite that off-spec here, but it isn't what I'd call a smooth taper.

So short of spending $15 on Alessandro's pots, is there a good alternative?

-g

FWIW, I have measured repeatedly with amp off and fully on (standby in "Play" position), and I don't measure any difference between those two settings using my Fluke. Hence my comment that it might be safer to measure it with the amp off.

I believe the "log" taper in some pots is actually made up of two linear taper sections joined together. You may be sitting right at the point where it changes slope. Yup...I'd had the same thought, because that is exactly what it feels like. If so, any recommendations for pots that do not apply th...

I'm a bit puzzled by the volts (30V?) reference, but I'll assume you're referring to kilohms? Elsewhere I remember several people saying that they preferred settings higher than 25k ohms to ground also. This struck me as odd, because on my own amp (low plate classic), anything over about 18k is too ...

Hi all, I tacked this on to the end of the thread about CTS pots, but hadn't heard back from that, so I thought I'd try giving it it's own thread: I've got an issue with the master volume on my D'Lite build. The taper is quite even right up to about 1:00, which in my band ends up being about gig lev...

I've got an issue with the master volume on my D'Lite build. The taper is quite even right up to about 1:00, which in my band ends up being about gig level (competing with another loud guitarist and a loud drummer on tight stages). At that point, the control gets as touchy as a rattlesnake. Tiny mov...

I don't know how closely matched they are. This is the basis for my question, though...

On one side of a Push/Pull cathode-biased amp, do *those* tubes have to be matched relative to one another? Or is it just that the pairs on either side of the P/P set have to be mirrored?

I have a cathode-biased amp with 4 power tubes. I tried doing some "mix and match" with some tubes I have, reasoning that since each power tube has its own cathode resistor, they should find their own operating point. So, for example, one matched pair of JJ 6V6's (one per side of the P/P pair), and ...

FWIW - If it is a properly designed cab, according to relevant design criteria, it doesn't matter if the port is front, side or rear...... It's the port loading that does the trick.... In theory, I think you're right. In practice, I'm not sure it works that way...or else the theory cited does not t...

Oof. I hate hearing about good folks having any kind of trouble, let alone this kind. You're in my prayers, Scott.

I've got the vertical 2x12 from Forte. Great cabinet. I've had a Port City and still have a Bob Burt V-12, but that Forte is a force to be reckoned with. Fantastic workmanship, too.

Cliff Schecht wrote:JJ KT88 tubes, if anything, are built like tanks. I think they have tone to boot. Great clarity in the high end (not harsh either), ballsy in the low end and roaring mids. Great complex sounding distortion in SE applications too.

Thanks for the tip, Cliff!

I took the statement about "he could never make 2 amps that sounded the same", as meaning if an artist liked an amp HAD built and went back later and said "build me another just like it" he couldn't do it. Maybe I misunderstood the statement. That's how I interpret it, too. And given how fastidious...