Tower of Power! What should I build with this old Sunn OT?

[mhartman]

I snagged this old Sunn 1200S OT on eBay the other day, what should I build with it? This pic is it sitting next to and intimidating an old Twin OT. This thing is HUGE.

[LeftyStrat]

Those go for almost two hundred on eBay, so you may consider selling it and buying a set of ClassicTone transformers. It's equivalent (I think) to the Dynaco a-451.

Otherwise, it would be a good candidate for an SSS, 4x6550.

[mhartman]

Yeah, I think it is similar to the A-451. I haven't seen where Classictone has actually come out with these though. I'm thinking a tubes up SSS type project, maybe built in a Marshall chassis or something. It would have to be sturdy, this thing is huge and heavy -- more so than I expected.

Those go for almost two hundred on eBay, so you may consider selling it and buying a set of ClassicTone transformers. It's equivalent (I think) to the Dynaco a-451.

Otherwise, it would be a good candidate for an SSS, 4x6550.

[Max]

what should I build with it?

Of course a Dumbleland Special 150W http://www.howl-co.com/stock_amp/st_amp ... eland.html or an ODS150W http://en.wikipedia.org/wiki/File:DOD_150_Back.jpg

... old Twin OT..

and a transition generation low plate classic ODS 100W http://www.audities.org/collection/dumble_1.html http://www.audities.org/collection/arch ... ve_a1.html
http://www.dailymotion.com/video/xu7q7w ... UCUTVfT7y4 (AFAIR: Steve Farris lead guitar on track one, Robben Ford lead guitar on tracks 4 & 7)

Cheers,

Max

[amplifiednation]

You know you want to build 150w amp. ..

[jelle]

Nice piece! Dumbleland or a Winterland?

[mhartman]

I'm thinking a Dumbleland would be fun. Anyone know of a source for a VERY sturdy tubes up blank chassis?

Did had go with aluminum for the chassis on his monster (150w+) amps?

[Max]

Did had go with aluminum for the chassis on his monster (150w+) amps?

Yes. Some pictures: https://tubeamparchive.com/viewtopic.ph ... 205#129205 The knobs shown on these pictures aren't original with the exception of the output impedance selector on the back.

Here's DLS 150W #009 on top of an early Dumble 4x12" cabinet: http://ameblo.jp/howlguitars/image-1081 ... 01929.html

Cheers,

Max

[ER]

I like the 24" wide 2.5" deep inward lip chassis from Watts Tube Audio. They have 6" wide and 8" wide for decent prices. They're pretty thick (.09) but I'd probably run reinforcements to mount transformers that size just to be safe.

I used one on my 100 watt with big transformers and it looked a lot like the dumbleland pics. I have some old sansui 1000a rocker switches I've been saving for a Jackson Browne style dumbleand build one day.

[img:680:474]http://personalpages.manchester.ac.uk/s ... 64-O-1.jpg[/img]

[img:680:474]http://personalpages.manchester.ac.uk/s ... 65-O-1.jpg[/img]

-E

[Luthierwnc]

Here's an old thread I started a couple years ago. You are going to need a stout chassis if you don't want to shim it like a Trainwreck.

https://tubeamparchive.com/viewtopic.ph ... ht=chassis

I've had Brisco make maybe a half dozen chassis' now and they were kind enough to give me a couple pointers. One thing I came up with on my own is that my template now has nicks in the corners so that the front and back fold over cleanly and the sides make up the short dimension instead of them all meeting together. That makes it much easier to weld without pocking the faces. If anything, the front and back extend a little past the weld. It is also easier to get the exact length right if you don't have to factor the bend into calculation.

Remember that for 1/8" stock you need about a 1/4" bend radius. I've seen dedicated guitar amp chassis with tighter bends but for off-the-shelf 6061 of 5052 sheet stock you need to hide the round somehow. That's easy for a tubes-up since the face fascia just needs to come down enough to cover the bend. Be careful with faceplates too. Common Alpha pots are barely long enough to poke through 0.125". My cheeseoid vinyl faces work fine but a Fender-style aluminum one will need pots with longer threads. FWIW.

Somehow I am banned from adding attachments to PMs. If you would like me to email you the most recent DXF files, send me a PM with your email address and I'll send them along.

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[PaisleyTube]

what about a tweed deluxe with 32 6V6s?

[mhartman]

what about a tweed deluxe with 32 6V6s?

Your comment just made me spit out my Cheerios. Too funny!