'65 Fender Super Reverb

[grtamp]

Hi all , a friend of mine give me a Fender Super Reverb to restore , what the most important work to do?
It's very old amp and my friend wants I check it, there are any noisy pots but I seems the sound is good. ( he has changed the power tube only one time , the rest is original)
The original parts are very difficult to find ,(pots and caps) or I think impossible.
any suggestions?
I will post some photos
Thanks

[Analog Assassin]

Try a little shot of tuner cleaner in the pots. I think a lot of people like the stuff from Caig.

You can get replacement pots but some say that it affects the value of the amp. If anything has to be replaced, save the originals.

I'd say replace the filter caps, or at least inspect them. If they look like there's any leaking or bulging, replace.

Replacing the power cable with a 3-conductor grounded cable is a good idea.

Again, save all the original parts.

Of course, bias the power tubes.

Check the tension of the tube sockets.

Clean the outside, put a little armor all or your favorite vinyl protectant on the tolex.

Then plug a good strat or tele straight in the amp, no pedals. Turn it on and just dig on that sound. One of the greatest amps ever made, IMO.

[grtamp]

Here some photos:

[grtamp]

again!

[martin manning]

I would replace all of the electrolytics. Some are 45 years old, but someone has changed the one on the bias supply board (which looks really big- 40 or 50uF is more than enough), and tacked another newer one in to replace half of one of the dual 25uF cathode caps. Who knows how old the newer ones are, and you should be able to get modern single replacements easily, and they will likely fit in the available space given their smaller size. I believe there are some new dual 25uF units being made (TAD in Germany, maybe?) if you want to go that way. Check the values of the power supply dropping resistors when the old filter caps are out. The screen resistors look ok (as far as the picture can reveal), but the values can be checked against spec in-circuit. After that, check all the voltages against the schematic and see where you are. I'll bet you can make it sound much better than it does now.

[jjman]

Rectifier tube looks small. 5y3 would not be an "appropriate" one if that's what it is.

[martin manning]

The reverb recover stage has a new plate load resistor, too. Probably this amp has been serviced a few times. Can't tell for sure if it's been done, but replacing the bias supply rectifier is cheap insurance.

[Bob-I]

I'd start with all new filter caps, including the C- just to be safe, no telling how long ago that was replaced. The screen resistors have been changed too so they're fine but I'd change the power tube grid stoppers as well. They're on the tube sockets so heat is a factor.

Go through ALL the solder joints, clean and retension the the tube sockets and clean the pots, don't forget the bias pot. Clean all the jacks, input, speaker, reverb, footswitch. Replace the AC cord, disconnect the ac hum switch. Get a good NOS rectifier as well.

Once all that's done play the amp for a few hours and listen for any crackling noises. If you hear any I'd start by replacing the plate load resistors. Use parts as close to the originals as possible.

Sweet amp, should sound amazing!!

[Structo]

Nice!
Like others have said, previous work has been done.
Replace all caps under the doghouse.
Be sure to document how it is wired before cutting anything.
Replace bypass caps.
I would also replace that bias cap, it looks like some residue has leaked out.

Be sure the three prong cord is installed correctly with the black going to the fuse then the switch.

[martin manning]

grtamp, what is the network that has been added to the speaker output jacks? Looks like someone wanted to use the extension jack for some other purpose, like a low-level line-out or something. It's probably not hurting anything, except that the shorting contact on the main speaker jack is now disconnected.

[grtamp]

If you mean that gray wired out from the chassis , It's a send / return passive jack .

[martin manning]

If you mean that gray wired out from the chassis , It's a send / return passive jack .

Missed that one, but I see it now; that's a nice trick.

I was referring to the cap glued to the chassis under the speaker jacks, and the two (that I can see) resistors. That makes the extension speaker jack a line out, doesn't it?

[jaysg]

I'd change the power tube grid stoppers as well. They're on the tube sockets so heat is a factor.

I would stand the new ones on end, instead of running them across the guide pin.