66 deluxe reverb bias cap

jacksparrow

Hi Guys What is the consensus on a 1966 deluxe reverb bias cap, i see some people mention upping the voltage rating to 25uf 100v from 25uf 50v.

Thoughts.

Ossyrocks

It's a good idea in my opinion. I have a 65 Deluxe Reverb and when I recapped it , I went for 50v caps in the bypass positions and 100v in the bias. Mine is a US voltage model so I have to run it on a step down. My wall voltage at home is 245v so when stepped down, it's still considerably higher than the 110v the amp was designed to see.

Rob

ICBM

You can increase both the voltage rating and the value if you want. Fender chose that spec because caps were relatively large and expensive then, so they used the minimum they could get away with. Increasing the value will probably reduce hum slightly, increasing the voltage rating simply makes it less likely to fail.

jacksparrow

thanks guys so would i be best to install a 50uf 110v .

RiftAmps

I use 50uf 100v in all of my F-style builds

ICBM

Yes, if it fits neatly on the board. You will probably find a modern 50/100 is actually smaller than the original 25/50!

If you've never done one before - when you change the cap, don't try to unsolder the ground (+) end of the old cap. Fender used the cap lead itself to pass through the eyelet and make the ground wire for the board, so you can't pull it out of the eyelet - so just cut the wire close to the eyelet. The other end can be unsoldered as normal.

jacksparrow

Thanks Chaps. I recently had  three prong cord installed and the clown who did it drilled the chassis and put a 20mm stuffing gland in. Came to take the amp apart yesterday and could not slide the chassis out the back due to the stuffing gland.
Had to unscrew bafffle and then the prick cut a bit of wood off of the spleen holding the baffle so he could get it in.

Was fucking fuming as the amp is mint and totally original.  gonna re do the three prong as i cannot keep taking the baffle out to take amp apart.

Thanks again for your wealth of info.

ICBM

jacksparrow said:

Thanks Chaps. I recently had  three prong cord installed and the clown who did it drilled the chassis and put a 20mm stuffing gland in. Came to take the amp apart yesterday and could not slide the chassis out the back due to the stuffing gland.
Had to unscrew bafffle and then the prick cut a bit of wood off of the spleen holding the baffle so he could get it in.

WTF?! Who did that?

jacksparrow

Gee electronics, which to be fair are usually shit hot, just do not let the new guy near your vintage amps.

ICBM

I'm actually baffled as to what he was thinking - not only has he caused unnecessary value-reducing damage to a vintage amp, that wasn't even the easiest way to do the job!

This is often a feature of bodge jobs, and I really don't understand it.

jacksparrow

^ Agreed he should of just phoned me and said i need to drill chassis, then i could of said don't bother.

He obviously drilled it then discovered he could not get the amp back in the cabinet then had to get it in through the front.

Still really pissed of over it.

jacksparrow

To be honest John and Barry are very good there but that new fella i could strangle.

ICBM

I would be discussing it with them. If this is a new employee who did such a stupid thing to a customer's amp without even checking that it was OK or the right way of doing the job, he needs re-training at least. And I would be asking for my money back on the job, even if the damage can never be put completely right.

DJH83004

Stunned by what I have just read!! probably happened because the guy didn't know how to release the two-piece cable grip in the back of the chassis, to replace the cable - they can be a bit tricky. But why was he let loose on such a valuable amp??
Getting back to your original question, probably very obvious, but get a decent cap, Sprague, F&T, Illinois, TAD or similar, as it is arguably the most important cap in the amp, giving a stable bias supply. Hope you get some redress on the mains cable bodge.

ecc83

Don't know the amp but you might as well go 'the whole 9' and fit a 105C jobbie if it will fit.

Dave.