1200S for a bass rig

[rp]

I was offered a 4,8 or 16 ohm cabinet in either mono or stereo.

I was thinking that should match up with the head.

[EdBass]

I was offered a 4,8 or 16 ohm cabinet in either mono or stereo.

I was thinking that should match up with the head.

How would you use a stereo cabinet using your 1200S amp?

[rp]

I was offered a 4,8 or 16 ohm cabinet in either mono or stereo.

I was thinking that should match up with the head.

How would you use a stereo cabinet using your 1200S amp?

Well that's just it...I guess I'm not since the head was made in the mono generation.
I'll just get a 16 ohm mono cab...whatever that is.

[rp]

Well I got my 1200S in today... and it looks good, however, when I plugged it in
it kind of hummed at me and then blew a fuse.

 

[EdBass]

Well I got my 1200S in today... and it looks good, however, when I plugged it in
it kind of hummed at me and then blew a fuse.

 

That's a shame! Oh well, box it up and send it to me and I'll dispose of it for you.

[rp]

Well I got my 1200S in today... and it looks good, however, when I plugged it in
it kind of hummed at me and then blew a fuse.

 

That's a shame! Oh well, box it up and send it to me and I'll dispose of it for you.

Maybe I should just fix it.

[rp]

Can I run the head with just the 6550 tubes? I think my rect tubes are bad....I pulled them and checked the
rest but am getting no sound through the speakers.

[EdBass]

Can I run the head with just the 6550 tubes? I think my rect tubes are bad....I pulled them and checked the
rest but am getting no sound through the speakers.

No you can't. It would also probably be a good idea to quit trying to make it work as it sits. You really need to find a tech in your area who specializes in, or at least is familiar with tube amps. Don't try to fix it yourself; based on your posts I don't think anything good would come from that. Also, be very careful poking around in that amp, there are potentially LETHAL voltages stored in the capacitors. EVEN WHEN THE AMP IF TURNED OFF AND UNPLUGGED!
One false move could end up being your last.
Conversely, your old Sunn would be child’s play for a good tech; they are pretty basic and straight forward.

Or...Just donate it my personal collection, where it will be refurbished and well treated, and have a great home with a whole bunch of its Sunn siblings.

[rick.heil]

Heehee....you wish it would get donated, Ed.

[EdBass]

I'm not a cheapskate - I'd pay for shipping!
The "buy low, sell high" theory has served me very well, and I have yet to find "lower" than "free"!*

Seriously, if rp wants to get rid of the 1200S, I'd wait for an eBay Sunn upswing and list it. Somebody will pay too much for it, and that's the best way to find them.
 

*DISCLAIMER - This is in jest, I am NOT attempting to coerce rp or anyone else to send me their tube amps free of charge.
Mind you, I will accept them; it's just not coercion!

[rp]

Can I run the head with just the 6550 tubes? I think my rect tubes are bad....I pulled them and checked the
rest but am getting no sound through the speakers.

No you can't. It would also probably be a good idea to quit trying to make it work as it sits. You really need to find a tech in your area who specializes in, or at least is familiar with tube amps. Don't try to fix it yourself; based on your posts I don't think anything good would come from that. Also, be very careful poking around in that amp, there are potentially LETHAL voltages stored in the capacitors. EVEN WHEN THE AMP IF TURNED OFF AND UNPLUGGED!
One false move could end up being your last.
Conversely, your old Sunn would be child’s play for a good tech; they are pretty basic and straight forward.

Or...Just donate it my personal collection, where it will be refurbished and well treated, and have a great home with a whole bunch of its Sunn siblings.

Well a buddy of mine who has a bit of a guitarist, circuitry background said he might take a look at it...though
he admits he knows more about solid state than tube amps...I think he just got one in fact.
I checked ebay for tubes and found some sovteks(?) 3 for thirty dollars so I might next try putting
fresh rect tubes in w/a spare.

No, you can't have my 1200S.

 

[rp]

I'm guessing the capacitors are the silver fixed tubes behind the 6550's??

He asked me for a schematic, but have had no luck in locating one. I wouldn't feel safe messing around in there...
though I have to admit I didn't know it could shock you unplugged.

[EdBass]

I wouldn't mess with rectifier tubes, particularly using the amp for bass. I would go this way;
http://www.webervst.com/ccap.html
Cheaper and less voltage drop - more potential for your power tubes, and they drop right in.

I'm guessing the capacitors are the silver fixed tubes behind the 6550's??

Those are likely the original can caps, maybe replaced, maybe bypassed, who knows? If they are original, they are almost definitely bad (have I mentioned to get a qualified tech?) and need to be replaced - actually they should also be upgraded from the spec on the schematic. (have I mentioned to get a qualified tech?) There are capacitors throughout the chassis, but those big filter caps have the most potential to ruin your day.

He asked me for a schematic, but have had no luck in locating one. I wouldn't feel safe messing around in there...

I have a factory schematic, I can PDF it to you.

I have to admit I didn't know it could shock you unplugged.

Not just shock you, it can freekin' KILL you!

[rick.heil]

Robin - the whole point of capacitors is that they store charge. Filter caps store HUGE amounts of electricity.  Getting shocked by one of those would be the equivalent of licking a live plug that runs to the wall outlet in your house.  It could (and probably would) kill you most quickly. 

BE CAREFUL!  I wouldn't want to see you on the news, in the hospital, or having your fingers shocked off and having to give your amp to Ed