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PostPosted: 24 Jul 2015, 09:09 
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Joined: 15 Nov 2013, 10:16
Posts: 250
Location: MB, Canada
So I scored what I think is a hell of deal on two Stromberg-Carlson 207 (same as model 20) amps. They're in mint condition, and they have all of the tubes in place, though I haven't powered them up yet or anything..
I found a guy locally selling them, and he also has one heck of a collection of NOS tubes..
So he sold me the pair of amps + 2 x NOS telefunken 6DJ8, and 2 x NOS Philips 6922 tubes for $140 total.. I think the tubes might be worth that much, judging by ebay.

Anyways, I don't know what to do with the amps! Looks like they were designed as PA amps, but I really don't have a use for them as originally intended.. I'm attaching the schematic for the amps.. And they're a design I'm not familiar with.

The iron is huge in these amps, very large output transformer, and power transformer for the tubes being used.
The manual I have lists the frequency response as 30Hz - 10Khz.. But maybe that's on the conservative side? Not sure.

Because I have a pair of them, I keep thinking some sort of music related stereo monoblock application.. But I'm not sure if they could be suitable for that.
I've also considered altering them to be more suitable as guitar amps, but I'd kinda hate to do that to them.

Anyways, any thoughts on what I could / should do with these things? I don't really have a use for PA amps.


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PostPosted: 24 Jul 2015, 09:11 
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Here is a picture of one of them.


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PostPosted: 24 Jul 2015, 12:57 
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Joined: 08 Aug 2009, 03:11
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Location: Chilliwack, BC
A fellow brought one into the store he modded for HiFi with some hammond iron. So there's an idea :D

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PostPosted: 24 Jul 2015, 13:14 
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Joined: 15 Nov 2013, 10:16
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Location: MB, Canada
Geek wrote:
A fellow brought one into the store he modded for HiFi with some hammond iron. So there's an idea :D


I suppose I could still use the factory power transformer, and go with a different output transformer..
I guess anything useful for me is going to include a complete redesign of these things..


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PostPosted: 24 Jul 2015, 16:06 
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Joined: 04 Jun 2008, 20:59
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Location: Arizona, USA
Hi, most likely there were for use in something like a large commercial building or even a school. They may sound better than the data indicates. Since I have all sorts of top performance amps I would just refurb them enough to be fully operational and keep them as collectables. Fixed and operational they may fetch a much higher price on the web.

Good listening
Bruce

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PostPosted: 24 Jul 2015, 18:30 
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Joined: 06 Apr 2009, 10:08
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Location: US Pacific Northwest
Gotta go with Bruce on this one. They look (at least the one pictured) to be in fine shape. I would do a new condition restore and either keep them as collectables or put them on the sales block. You should be able to get significantly more than you paid.

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PostPosted: 24 Jul 2015, 19:29 
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Joined: 15 Nov 2013, 10:16
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Location: MB, Canada
Suncalc wrote:
Gotta go with Bruce on this one. They look (at least the one pictured) to be in fine shape. I would do a new condition restore and either keep them as collectables or put them on the sales block. You should be able to get significantly more than you paid.


That's what I'm leaning towards.. It would just feel wrong to start messing with them too much.


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PostPosted: 30 Jul 2015, 22:07 
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Joined: 09 Oct 2012, 19:43
Posts: 355
Location: Vancouver Canada
I would change the caps first thing and fire em up. Some of the wire coatings may be dry so gentile hands and wire is available by the ft.. The pic shows a phono input so they may very well have better performance than the specs suggest. In any case t would look smokin, in any hifi setup, Then if you decide to further the mods you are in the same delema just later having enjoyed the turns. Either way worth the investment as they are in mint condition and very unique and winter is just around the corner.


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