Restoring and servicing a trashed vintage amplifier

[roundabout145]

why do you have to connect the pots with wire when theyre connected together with the chassis?

[CKS5000]

makes sense two wrongs don't make a right

[patfurlan]

they are the .0047 or .005 in the tone stack

[skidrowe9]

what are them green, blue, and red caps called?

[patfurlan]

@skidrowe9 people call them tropical fish ... they were made by mullard an the colors are the value code just like resistors

[skidrowe9]

@patfurlan could you tell me what value they are?

[BoscoeFrance]

Is there a book you could recommend to gain some knowledge about tube amps.

[jerid71]

Pat - just discovered your videos - excellant stuff - keep them coming - anything on a bass mate (w EL84's) would be good - Ted G. !!

[PLUMBdogg]

What do you look for when sourcing out replacement filter caps? Are there particular brands that replace particular vintage caps better than others? I got some Astrons in a 5e11 that need replacing.

[patfurlan]

German or USA made caps are good  chinese ones BAAAAADDDDD

[PLUMBdogg]

Thanks! I got hold of an old Sylvania(green letters, black base) 6v6GT with 7 pins, I threw it in my Champion 600 to test it out. I only got some faint sounds then some hum so I took it out. Now my Champion 600 don't work! I thought pin 1 was dead on them old tubes, think I ruined my transformers? Not a biggie cuz I wanna do the tweed mod you posted, and swap for some Mercury Magnetics and a Weber speaker too. All the amp does now is fizzle a note very faintly when the volume up full.

[maynardcat]

Very interesting video. I wish I had more knowledge of altering the original coupling caps to improve the sound quality. I have a 1948 preamp AM FM radio that I would like to do the same thing to. I have read that there are more expensive better quality caps for replacing in vintage amplifers to preserve their original warm richer sound.

[patfurlan]

when you exchange a cap ie from .1 to .01 you shift the bottom up 1 octave 1 decimal place = 1octave

there are actual formulas if you want to calculate an exact cutoff but in the guitar mate we are moving the low cutoff from 8hz to 80hz if I remeber correctly ... since most guitar speakers do not operate below 75hz

all you are cutting out are the rumble and "fart" elements of the distortion voice ...

you best tools for eqing an amp are your ears trust them

[magnus264]

Nice. just I don't understand: on a hand you underline not to overfilter to keep original sound, on the other you made a several values components changes... isn't it a contraddiction?

thanks

(sorry for my not perfect english, i'm technician from Italy)

[patfurlan]

In this case since the amp was already missing parts I took the opportunity to dial it in for the sound I like. I am willing to make changes to expand its "Vintage character" I also used a Twin sized output transformer. The goal is to get a Vintage Big amplifier (jtm 45) sound in an 18 watt package for club use. Around here the biggest thing I see is people building Vintage style amps but "improving" the filtering then using the thing with an attenuator to try and control the power.

[patfurlan]

Used this amp today at an outdoor gig, It cuts the mustard !

[BadChizzle]

Don't know much about tube amps, but I always lime your videos. Thanks!

[EVTMods]

Nice, Sale me the mustard caps.

[patfurlan]

the mustard caps are not important my best sounding YGM3 is a Brand NEW re-issue ... thats the one you hear most often in the band videos