Question:
I was looking at some guitar amp mods the other day and ran across this
http://www.torresengineering.com/addtubrectoy.html
it says you can add a rectifier to your amp. is this really possible and is it safe for your amp to try? are certain rectifiers specifically for high gain amps.
Answer:
Originally Posted by nick2282 I was looking at some guitar amp mods the other day and ran across this
http://www.torresengineering.com/addtubrectoy.html
it says you can add a rectifier to your amp. is this really possible and is it safe for your amp to try? are certain rectifiers specifically for high gain amps. You'd probably want a 5AR4 (found in the B-52 AT series) or a 5U4G (two in the Mesa Dual Rectifier).
is it possible? sure...
is it safe? who knows
is it necessary? if you think it is.
Answer:
yes, you can do it.
however, i would higly recomend that anyone who does not have a firm understanding of electronics try this themselves. you'll be playing with some very high voltages, if things are not done properly they could quite easily blow something up, at the least start an electrical fire.
that out of the way, i guess the trick would be finding the poper rectifier tube, in order to use the existing transformers and such. once you work all that out, it would be mostly a matter of planning out how to wire things, and ensuring that doing this isn't going to affet anything else in the amp.
EDIT: well i guess steve beat me to it.
Answer:
Originally Posted by What5647 that out of the way, i guess the trick would be finding the poper rectifier tube, in order to use the existing transformers and such. once you work all that out, it would be mostly a matter of planning out how to wire things, and ensuring that doing this isn't going to affet anything else in the amp.
EDIT: well i guess steve beat me to it. according to the torres site, you actually have to install another transformer for the modification to work.
Answer:
ah, you do? i as looking to see if it said that, but missed it.
man, that might make this a really complex mod in that case. also, keep in mind all this would take up quite a bit of room, and that you might also have to take into account the added heat buildup.
Answer:
Originally Posted by What5647 yes, you can do it.
however, i would higly recomend that anyone who does not have a firm understanding of electronics try this themselves. you'll be playing with some very high voltages, if things are not done properly they could quite easily blow something up, at the least start an electrical fire.
that out of the way, i guess the trick would be finding the poper rectifier tube, in order to use the existing transformers and such. once you work all that out, it would be mostly a matter of planning out how to wire things, and ensuring that doing this isn't going to affet anything else in the amp.
EDIT: well i guess steve beat me to it.
would there be enough voltage to kill me or send me to the hospital if i screwed up?
Answer:
well, since you'd be working on it with the power off, (at least i would hope so) you'd be well away from any hazardous voltage when you turn the amp on the first time. unless somehow the guitar line in gets connected to some high voltage, wich ought not to be an issue.
Answer:
Originally Posted by thesteve You'd probably want a 5AR4 (found in the B-52 AT series) or a 5U4G (two in the Mesa Dual Rectifier).
is it possible? sure...
is it safe? who knows
is it necessary? if you think it is.
i dont know if its necessary, but wouldnt it only improve my tone?
Answer:
a common misconception about rectifiers is that the can change your amps tone. this is untrue, as they are completely seperate from the signal path. a tube rectifier, however, will give you that "sag" sound. the sag sound is created when the rectifier cannot convert enoguh AC power to DC to sattisfy the amps' needs. (i think, someone correct me if i'm wrong.) i wish i could better describe what sag sounds like, but i don't really know what it sounds like, lol.
Answer:
Originally Posted by What5647 well, since you'd be working on it with the power off, (at least i would hope so) you'd be well away from any hazardous voltage when you turn the amp on the first time. unless somehow the guitar line in gets connected to some high voltage, wich ought not to be an issue. indeed. i'd make sure you drain those filter caps off ahead of time. Messing up with one of those might skip that whole trip to the hospital Originally Posted by nick2282 i dont know if its necessary, but wouldnt it only improve my tone? "improve" is such a fickle word. Some people like rectifier sag...other people hate it, and plenty of people can't even hear the difference enough to care.
Answer:
Unless you are an electronic tech, I would strongly advise to have it done professionally. Tubes operate with high (and low) voltages, aside from your own health, you could easily turn you amp into a molten heap of garbage. That is major surgery, definitely not for amateurs. Its not like mods where you simply change values of resistors or caps.
The sag from tube rectifiers occurs when the power tubes are drawing more current than than the tube rec can supply. Its my understanding that its going to be similar to using a compressor set as a limiter. I don't think that all amps with tube recs will necessarily ever even get to that point. As one example, a Fender Champ, I think, will never achieve sag - I never heard it or recognized it in mine. The amount of sag depends on how under-powered the power supply is for that amp. Of course when the power tubes are drawing enough current to reach the point of sag, its gotta be cranked - not just the preamp gain, but the power amp section. You won't get sag with the gain/pre turned up and the master volume on 4. I would venture to guess that with a saggy power supply that there would be a sweet spot where the desired amount of that type of compression sounds good - and that exceeding that sweet spot will just sound like mush. I dunno, but it seems that sag would be undesireable for heavy distortion, that it would just mush out....
Answer:
i guess i wont try to do it myself, i would hate to screw up my amp