Sunn 2000S

[Spliffpfunk]

Hi everyone
I'm a new member here and I've recently just purchased a Sunn 2000S which is in very good shape. When I got it home I plugged it in and played it for about 30 minutes . It is very quiet and has not scratchy pots. I opened up the back and removed the chassis and found that of the 4 power tubes that were in it , there wer 3 different makes. Peavey, Tung Sol and another so old that the lettering was gone! It has 2 Mullard GZ34 Rectifiers and a Sovtek 12AX7WA and another GE preamp tube that is so old the writing is gone. Even with all this it still sounded good. There is no data plate on the chassis, only a date of 4-20-70 and this one does have the Bass Boost. Now the input I would like to hear from the forum is this:
A. What tubes would you recommend? Please give a couple of choices from expensive to not so expensive in price and quality, Which Brand would be more suited.
B. Where do I locate Schematics, Service Manual and Owners Manual? Every other Sunn I've owned had a schematic glued to the top inside of the chassis box. This one has none.

Thanks

[Tom Phillips]

Schematic Heaven seems to still be off the web so I'll email you a schematic if you will send me your email address. Send private mail through the newsgroup if you don't want to post it. (Tried to attach it here and tried to private email it to you but the system would not accept the file)

It's very common to find old amps with a variety of power tubes installed since, in the past, people were not so concerned about replacing the whole set at one time. I think I'll leave it to others to recommend tubes. If money were no object, I'd procure Genalex KT-88s

[J Martin]

The St. Petersburg Svetlana 6550 tubes work well in those amps. The new Genelex KT88's are great tubes, but will cost you twice as much. My lightly used 2000S still has the original Tung Sol 6550 and Mullard rectifier tubes.

[Enzo]

Try Schematic Heaven again. Seems to me it came back up a couple weeks ago. I just now checked and it was there for me. Though since its return, it seems to be on a very slow server, might take a minute for the screen to show up.

[soundmasterg]

Here is where you can find everything Sunn, including schematics and sales brochures.

http://sunn.ampage.org/

I use JJ KT88's in my Sunns and they sound and work great. I've got a 200S and a 2000S. I also have experience with the Winged C 6550C (in my SVT) and they sound and work fine going on 8 years now. I've heard good things about the new Genelex KT88 but have not tried them yet. Other known good tubes are the Winged C KT88, EH KT88, and Tung-Sol reissue 6550.

For preamp tubes, just about any 12AX7 is better than the one you have in there, but some nice ones are the new Tung-Sol reissue 12AX7, JJ ECC803S and JJ ECC83S, EH 12AX7, Sovtek 12AX7LPS.

For the phase inverter tube (thats the GE that has everything rubbed off), you need a 6AN8 or a 7199, most likely the 6AN8. Those are only available NOS but aren't too expensive. The one you have may be just fine too.

The GZ34's I'd just leave in there as they are most likely just fine. I would get a couple Copper Cap WZ68 solid state replacements from Ted Weber however and have them as backups to those GZ34's. Anytime you change the rectifier though you need to rebias the amp so keep that in mind if you change those GZ34's. You can find the Copper Caps at www.tedweber.com.

For the rest of the tubes, you can get the JJ's from http://www.eurotubes.com/ . The owner there is a Sunn nut and he'll hook you up with something good. I am a dealer and can also sell you any of these tubes, or you can get the JJ's and all the others except the new Tung-Sols at www.tubesandmore.com. If you're interested in having me quote you a price, then email me at soundmasterg [at] yahoo dot com.

I'd suggest to replace the electrolytic caps in the amp if they have not been replaced too. Due to the higher wall votlage these days, the can cap in the Sunns is over it's voltage rating, and if you do a replacement of the electrolytic caps in the amp, you should go with series connected discrete caps for a 700v rating for the first three sections in the amp. You also need resistors in parallel with each cap if you use a series connection. Installing these and leaving the can cap in place but just disconnecting the circuit from it gives you an amp that can handle the higher voltages these days. If you don't know what I'm talking about, then it would be a good idea to find a tech who can do this for you.

Hope that helps.

greg

[Tom Phillips]

... The new Genelex KT88's are great tubes, but will cost you twice as much...

Can you explain? I was really just joking as NOS Genalex KT-88s are very rare and will cost you hundreds each if you can find them. Is someone using the name again?
Tom

[soundmasterg]

Yes, the New Sensor company owns the rights to the Genelex name, in addition to the Tung-Sol, Mullard, EH, and Sovtek names. They also own the former Reflector factory in Russia and make more than 50% of the world's tubes. They have come out with a Genelex KT88 copy, and of course they are calling it the Genelex KT88, but made in Russia. So far they have been getting some very nice reviews from some well respected dealers like Jim McShane for instance. Their Tung-Sol stuff is also very good so far. You can check their products out at www.newsensor.com, and also read up on other tube vendors sites like Mr. McShane's for instance about some of New Sensor's products. Go to this link and click on some of the tube vendors links at the top of the page for more info.

http://www.webervst.com/tubes/index.html

greg

[Spliffpfunk]

Genelex (new) KT88

I found out earlier today that they are made in Russia. I managed to buy a matched Quad for $175

[JLD2201954]

Sunn 2000S

Greetings!

I'm new at this...sorry. I have a SUNN 2000S head with the base boost switch. I've had it for so many years and it is in fair condition. It works! What is this amp worth $$? I'd like to sell it.

Jerry

[soundmasterg]

Take a look at ebay's completed listings.

Greg

[JLD2201954]

Thanks!

Thanks Greg, but I did check E-Bay, and there were no listings. Only T-shirts, with Sunn 2000 logos. Maybe I should list it on E-Bay? In your opinion, what would be a fair bid or price?

[loudthud]

Ebay has changed recently. To look at completed listings you have to press "more options" in the pane on the left and select it in a box that pops up. A 2000S recently sold for an astonishing $1691.66 . This is a good amount more than any in recent history.

[JLD2201954]

Thanks!

Thanks for the info buddy! I'll check it out.