Tube Amp Archive

OK - you have a lot of reading to do. did i say something wrong? are tube characteristics identical just because the have they same pin layout? i would think not, but you seem to disagree. anyway, in my first post i made clear that i know little about amps in particular and electronics in general s...

It'll work - just not sure you'll like it. One way to find out. i gave it a try, out of curiosity, and didn't find much of a difference between the 12ax7 and the 12at7. it certainly worked, which is good, but red-plating power tubes also work - for a little while. my point here being "just because ...

It should be ok. should? does that mean there's the possibility it might not be ok? The AT7 has less gain, so it will change the sound. Clipping will change. i don't mind if there's a perceivable change in the sound, as long as i'm sure the amp isn't being harmed. What are you looking to do ? i hav...

still regarding the tsl60, is it safe to replace the 12ax7 in v4 (phase inverter) with a 12at7?

For reliability keep them running, don't switch them on and off like fairy lights i usually switch the amp on, play for an hour or so, then switch it off. i do this no more than 2 or 3 times a month. the stock =C= el34 tubes are still sounding good despite being 4 or 5 years old. perhaps, all thing...

480V, no problem for a KT77, maybe the screens should be held much lower for reliability. Depends on the designer's choices. i believe that due to design of the amp itself, the voltage for the screens is nearly the same as for the plates. marginally lower, that is. "not much in the harmful directio...

I don't know the tsl marshall, but my hunch is that it will be around 450V on the plates and so long as you adjust the bias you will be fine. i haven't measured my amp, but tsl60's, from what i understand, tend to be closer to 480V. Theoretically the mis-match, that you are rightly cautious about, ...

hi everyone. i know little about amps in particular and electronics in general but i'm trying to understand how well, or how badly, kt77's would work on a jcm2000 series (tsl60 version). from what i've read so far, it seems that (and please correct me if i'm wrong) the reason you connect a 8-ohm loa...

Voltage is always relative: one thing being measured with respect to another. Therefore grounds are also relative. There can be many different grounds in an amplifier. Where three-wire power cords are used, the ground wire is connected to the chassis. This is the "safety ground" and is there to shu...

http://www.ese.upenn.edu/detkin/instruments/misctutorials/Ground/grd.html http://en.wikipedia.org/wiki/Ground_%28electricity%29 i appreciate that you've posted those links, but the only thing i could find that slightly resembles an answer for my questions is: "Voltage is a differential quantity. To...

i've decided to be a bastard and ask more stuff anyway, even if it this might not be the most adequate place. do you know when people talk about making readings with a multimeter, they always say things like "measure between pin X and GROUND ? what if the amp isn't grounded? what if it's an old amp ...

why? what are you afraid of blowing? Just make sure there's a little wiggle room in your speaker cabs. There's a reason the historic Marshall is a 100watt amp with 2 quads of greenbacks. The first speakers were rated at 25 watts and a single 412 would blow. well, i wasn't afraid of blowing anything...

Reeltarded wrote: What did you blow up?

nothing, gladly.
but i know i'd be upset if i did.

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there's more stuff i wanna know.
may i ask it here?

[...] If your master is on ten and you turn the preamp up until you hear distortion you are most likely pushing past whatever stated wattage the amp is. i'm not sure i feel so joyful about hearing that. [...] There are a lot of different "100W" Marshalls; with hot pickups, some of them can likely d...

diagrammatiks wrote:tube amps put out more power when overdriven.

all wattage ratings are always measured at clean power.

so if i have the master volume at 10 but the preamp only at 3,
am i crossing the line?