1969 Sunn 1200s Capacitor Question

[Ryanx]

does anyone have a list of caps handy that i could use to recap this 1200s?  much appreciated

[EdBass]

There are a lot of posts regarding re capping the old Sunns. There are various methods, even kits available to upgrade the power supply filters, depending on what your goals are for the amp.
Regretfully, just replacing the factory caps with the same values is arguably not a viable option. The biggest obstacle is the 20mfd, 20mfd, 20mfd, 30mfd  can cap that's rated for 525 VDC, which is a little light for modern wall voltages. It's also hard to find, although you can get them from Triode Electronic.

I won't get more in depth, because it's been hashed out here ad naseum in past posts.



Of course, I will give the obligatory warning;

DANGER!!! Even unplugged old amplifiers, particularly high powered tube amplifiers, can store potentially lethal energy. If you don't know what you are doing (like for example if you don't know what I'm talking about), please take it to a trained professional.

[Ryanx]

haha thanks for the warning EdBass, i searched a few times but never came across a shopping list of the best and proper caps for the 1200s.  i had great success making a thread like this for my model t a while ago and figured i'd go the same route now that i've traded for the 1200s.  i'd be buying these caps and giving them to my guitar tech.  thanks.

[EdBass]

Here's an old post that covers filter sections, with some suggested mods;

http://sunn.ampage.org/sdp/index.php/topic,4647.0.html

This is the SDS board mounted in one of my 2000S's, it should mount as easily in your 1200S, plenty of real estate to work with. As you can tell by the unused holes in the chassis Sunn used the same chassis for all of the 1000 series amps, just changed the faceplate.



It tightens the bottom end up, and probably makes a little more power also. I use it for bass so IMO it performs a little better for that application, but it might not be the way to go if you want to get real "nasty" with it.
Depending on what you want your amp to do, I might have some other less labor intensive ideas, as well as a 1200S schematic. I'll email a PDF copy to you, your tech will probably find it handy.

PM me the email address you want me to send it to, and give me an idea of what you are using the amp for.