OT: Champ amp Tubes and tranny

[marrstians]

hey... i just bought a champ clone for a decent price but i'm not sure if all the parts are right or they just work in the circuit... does any one know what transformer should be used and the voltages for it? also this guy used a 6x5 rectifier tube instead of the 5y3gt... i know they're different pinouts but could i just change the wiring on the pins and slip the 5y3gt in or would i not really notice the difference in sound so should i just leave it alone?

[Peter Snowberg]

I don't have any tube data next to me, but the 6X5 has a 6 volt filament while the 5Y3 has a 5 volt filament so you can't just rewire the socket and swap the tube. You could use some very big diodes or a resistor to drop the voltage by a volt, but I don't know if you would gain anything in the process.

There are two numbers to look at, the first is the maximum current the rectifier will handle, and the second is the voltage drop of the rectifier. The max current is going to be the most important figure. My guess is that they are both very able to supply the amp any you would hear zero difference.

Take care,
-Peter

[Lonestarjohnny]

6X5 is a full wave high vacume rectifier with a 6s base connection, filiment volts is 6.3 volt, filament amps 0.6, tube voltage drop = 22v. at 70 ma dc per plate, Max. dc outtput current=80ma   Max peak inverse voltage =1250volts ;rms supply voltage per plate=360 volts  Max peak current per plate=245ma
5Y3 is a Full Wave high vac. rect.,with base conection 5Q, filament voltage = 5 volts, filament amp = 2.0, tube voltage drop60v. at 125ma per section, max dc output current = 125 ma, max peak inverse voltage = 1400 volts, max rms supply voltage per plate= 350 volts, max peak current per plate= 375 ma.
what this tells you is the tranny is undersized for the 5Y3, better like Peter said, stay with the 6X5. or go with a new tranny like the Champ tranny at Angela Music.

JD

[Eric H]

what this tells you is the tranny is undersized for the 5Y3, better like Peter said, stay with the 6X5. or go with a new tranny like the Champ tranny at Angela Music.

JD

Not necessarily undersized, but most likely missing the usual 5v rectifier tap. Sounds like a clever use of resources, to me. How does it sound?

-Eric

[marrstians]

ok... here's what i got... the tranny in it right now is a hammond 269BX 38VA, sec. 150-0-150, DC ma 75, Fil. #1(rectifier)--, Fil.#2(heater) 6.3v @ 2.0a.... i think that's a lot lower power rating then a normal champ... i think they're usually about 350-0-350, dc ma 90, right? i wonder how much different this affects the tone and proformance of the amp... i'd like to get a real champ and put them back to back and hear the difference but i don't have the cash to do that right now...

[Lonestarjohnny]

what makes you think its not undersized, tranny is rated for a 6x5= 80ma, 5y3 is rated 125ma's,to me thats a 45 ma's that it don't got to give,
so if you want a saturated tone from the get go and a tranny you can fry eggs on sounds like a winner to me,
JD

[Eric H]

what makes you think its not undersized, tranny is rated for a 6x5= 80ma, 5y3 is rated 125ma's,to me thats a 45 ma's that it don't got to give,
so if you want a saturated tone from the get go and a tranny you can fry eggs on sounds like a winner to me,
JD

A single 6v6 pulls 30-40 ma --a 5y3 can run two of them easily, and is overkill for a single 6v6. The rectifier used gave no indication of the transformer rating --which you can see is not under-rated --except in voltage.

[Eric H]

ok... here's what i got... the tranny in it right now is a hammond 269BX 38VA, sec. 150-0-150, DC ma 75, Fil. #1(rectifier)--, Fil.#2(heater) 6.3v @ 2.0a.... i think that's a lot lower power rating then a normal champ... i think they're usually about 350-0-350, dc ma 90, right? i wonder how much different this affects the tone and proformance of the amp... i'd like to get a real champ and put them back to back and hear the difference but i don't have the cash to do that right now...

If that's really what's in there --your B+ is probably arount 160-170 volts --way low for a 6v6. You could change the rectifier to a full-wave bridge, which will put you over 400v --but there are ways to reduce this.

How does it sound?

-Eric

[csj]