Sunn tube amp question...

grunlohd · #1 03-03-2011, 02:53 AM

Apologies if this same question has been asked and/or answered before. I've been searching the forums, and I haven't found any specific info that answers my question. My question is this: I recently acquired a Sunn 1000S head. It came to me without tubes, though. Where can I find information on what kind of tubes I should use in it? It's got seven sockets, so I know how many tubes to buy, but how can I find out the right size, wattage, etc.? I'm basically a newcomer to the all-tube amp world, and I would appreciate any advice from people who know how to treat their tube amps right. I have a schematic for this amp, but that's not what I need. Any help would be greatly appreciated.

electroken · #2 03-03-2011, 03:54 AM

The schematic should have the tube numbers right next to the symbol for each tube. If you can post the schematic and a photo of the underside of the chassis, I'm sure dozens of people here (me too) can tell you what to plug in where.

D.M.N. · #3 03-03-2011, 04:23 AM

A 1000s? With 7 places for tubes? Hm, strange as the 1000s was discontinued before they switched to SS rectifiers, and normally should have 9 holes, for the 5AR4 rectifiers. However, there are plenty of anomaly Sunns, so you may have a bit of an unusual piece. Anyways, here's the tube layout.

BassmanPaul · #4 03-03-2011, 09:05 AM

Remember that the new 6550 tubes will need to have their bias setting checked by a tech. They're not plug and play.

grunlohd · #5 03-04-2011, 12:25 AM

Apparently, there are six sockets. But you kind folks can see that from the attached photo, I hope. Thanks to those who have already offered advice-- any of you want to change your suggestions, having seen a pic? Further information, scoldings about what an idjit I am for miscounting sockets, etc. are welcome.

the mojo hobo · #6 03-04-2011, 02:58 AM

The pic is awful small but it looks like the diagram above. The 6AN8 looks to be there with a shield over it and the 12A?7 tubes are hiding behind the transformer.

grunlohd · #7 03-04-2011, 03:12 AM

I know the pic is small. I had to make it that teeny so that it would meet the 640 by 640 pixels requirement. Apologies. But thanks for squinting, and offering advice anyhow.

johnk_10 · #8 03-04-2011, 03:18 AM

your 1000S should have 6 (large octal) tube sockets along the back of the chassis. looking from the back, they are left to right- 5AR4 5AR4 6550 6550 6550 6550
.
there also should be three smaller tubes under the meatal shields (1-12AX7, 1-12AU7, 1-6AN8).

panama · #9 03-04-2011, 07:04 AM

You should take it to a good amp guy and have them do this. You shouldn't just pop tubes in.

panama · #10 03-04-2011, 07:05 AM

Quote:

Originally Posted by grunlohd

Apparently, there are six sockets. But you kind folks can see that from the attached photo, I hope. Thanks to those who have already offered advice-- any of you want to change your suggestions, having seen a pic? Further information, scoldings about what an idjit I am for miscounting sockets, etc. are welcome.

No there are 9 sockets. Count em. 9.