As a part of a purchase of some tube gear, I picked up this really nice Sherwood S-5000 integrated. The lady actually gave it to me for free because I bought a bunch of other stuff and got a friend to come buy the rest of her late husband's hoard. It is completely original and fully functional after bringing it up and doing some quick testing. No hum at all, and it really sounds great. All 5 12ax7's are the original telefunkens and test strong. 7199's are original, as is the rectifier. I can barely make out the letters "SHERW" on the rectifier. The outputs are not original, but they are nice Sovtek EL84M's that must be close to brand new.
For restoration, I plan to add a CL80, replace the electrolytics and the rectifier, and see how it performs. I am going to use new caps under the chassis for the small 30/20 can and the common-positive bias can. Since there is so little room in the chassis, I ordered a CE can cap from AES for the main power supply can. I also ordered new coupling caps that I may replace preventatively.
Most of that seems pretty straightforward, but I already have a question about replacing the rectifier. I was planning to use two 1.5a 1000v diodes to create a new bridge on a terminal strip for the rectifier replacement as see on this thread, but I have some GBU4G 4 amp rectifiers that I have used on a fisher and a scott. These have a DC+, DC-, and two AC ~ legs coming off of it, but the original rectifier has just the two ~ leads from the transformer and one lead that goes to the bias supply. Is the original rectifier grounded through its case to the chassis and would I just have to ground one of the DC legs of the GBU4G rectifier if I use that instead of the diodes? I may have to use the diodes, just thought using the GBU4G may be cleaner and easier if possible.
Since the voltage from the new rectifier will be higher than the old rectifier, I may also need help placing a voltage dropping resistor to get the voltage down. I ordered a handful of different 5W resistors, I think around 8-10ohm to try. Will a 5W resistor be suitable for this?
Guess I have more questions than I thought. I should have parts by tomorrow and start on it this weekend. Thanks for any help.
For restoration, I plan to add a CL80, replace the electrolytics and the rectifier, and see how it performs. I am going to use new caps under the chassis for the small 30/20 can and the common-positive bias can. Since there is so little room in the chassis, I ordered a CE can cap from AES for the main power supply can. I also ordered new coupling caps that I may replace preventatively.
Most of that seems pretty straightforward, but I already have a question about replacing the rectifier. I was planning to use two 1.5a 1000v diodes to create a new bridge on a terminal strip for the rectifier replacement as see on this thread, but I have some GBU4G 4 amp rectifiers that I have used on a fisher and a scott. These have a DC+, DC-, and two AC ~ legs coming off of it, but the original rectifier has just the two ~ leads from the transformer and one lead that goes to the bias supply. Is the original rectifier grounded through its case to the chassis and would I just have to ground one of the DC legs of the GBU4G rectifier if I use that instead of the diodes? I may have to use the diodes, just thought using the GBU4G may be cleaner and easier if possible.
Since the voltage from the new rectifier will be higher than the old rectifier, I may also need help placing a voltage dropping resistor to get the voltage down. I ordered a handful of different 5W resistors, I think around 8-10ohm to try. Will a 5W resistor be suitable for this?
Guess I have more questions than I thought. I should have parts by tomorrow and start on it this weekend. Thanks for any help.