You might need a cap job if.......

[RETSUB007]

thanks , now im ready caps are ordered from clay so , , ps i have ocd so neatness is a curse carl

[thames]

I prefer the 32+32, but you'll never hear a difference between the two.

--mark

Hello Mark and others, why do you prefer the 32+32 over the 16+32 (stock) ?

Also, what to expect to switch from 160uf to 100uf on the BIAS section ?

[mhuss]

More filtering in the early preamp stages means quieter. There's no 'sag' or anything else going on there, just reducing ripple on the HT.

--mark

[mhuss]

I've added slightly different versions of these pix to Hiwatt.org:

http://hiwatt.org/tech.html

--mark

[Stu_R]

I've added slightly different versions of these pix to Hiwatt.org:

Thanks, not as obviously grim (to the uninitiated) as I was expecting, so I'll have to make a close scrutiny.

........... and thanks for the add of the new pics in the OP - very much clearer now to my untrained eyes.

[Schuabber]

Hi! I will recap my 78 DR504 and I already know about the resistors which clean up the high voltage from the caps.
I can see those resistors in my amp, but in the side filter cap, which has three cables soldered, there is no resistor! Is this cap safe to remove too?

[Dr.HI-TONE]

yes the gray wire is the ground

[Schuabber]

Thanks Dr.HI-TONE!
Really fast answer!!

[guitman]

Performed a cap job this weekend on my Biacrown DR504 OL. I have a feeling the old caps were original, as they had the blue solder that was used throughout the rest of the amp and apparently indicative of the guy who built the amp (Harry Joyce). They were all bulging or burst just as in the pics of this thread. So, that puts the old caps at around 1982.

Fired up the amp for rehearsal after the job, and it's like I have a brand new amp! Super warm clean tones and beautiful heavy distortion when cranked up. No more garbage at the end of a note, and no more volume crumbling and dropping off at the end of a note or when lightly brushing the strings. Everything can be heard through the amp now, so much more definition. I thought the amps was great before, but this really kicks it up many, many notches.

Here is my final shopping list for this job:

https://imgur.com/KCEXHCg