Duncan Convertible amp question

Alvin Lee Fan

Alvin Lee Fan

New member
It's about the extension cab, actually. There's a 1x12" cab on eBay right now that I'm interested in. Anyone have details on the type of speaker, wood, etc? How do these sound compared to modern extension cabs?

This speaker is labeled Convertible 100 and is 8 ohms. I've read these used different speakers over their lifetime, everything from EVs to Celestion Sidewinders. This one doesn't look like an EV, it appears to have a stamped frame. But, I need a 100w, 8 ohm 1x12 cab and this one fits that description :D

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Re: Duncan Convertible amp question

I don't have the answer to your question but I can offer this...

The speaker in that picture is not an EV and it is not a Celestion...

At first glance it looks to me like an Eminence...
 
Re: Duncan Convertible amp question

Yeah, pretty sure it wasn't an EV. Didn't know if Duncan relabeled the Celestions or not. I'm still interested in any details on this cab though.
 
Re: Duncan Convertible amp question

Alvin Lee Fan said:
Yeah, pretty sure it wasn't an EV. Didn't know if Duncan relabeled the Celestions or not. I'm still interested in any details on this cab though.
Click to expand...

They might have use Celestions at one point but a Celestion speaker only have 4 spokes on the frame...that speaker has 6.

You're best bet might to be email Duncan support...there is very little Convertible info on this forum...strange as that is!
 
Re: Duncan Convertible amp question

FYI, the seller says he has 3 other cabs he'll be listing soon. He lists them individually to avoid confusion. There's a twin to this one, then two others that are like these except with different speakers.

I got mine, get yours!

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Re: Duncan Convertible amp question

Good to see you ALF, you haven't been around in a long time
Al
 
Re: Duncan Convertible amp question

I lurk
Lurking.gif
Mostly in the trading forum.

I ventured inside again a few days ago and you know, you get hooked on the stuff that goes on in here :laugh2:

I see you have another killer new amp!
 
Re: Duncan Convertible amp question

the guy who invented fire said:
So, what model Sundown head are you using with it????
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Actually, it's a Sundown that I modified, my first really big amp project. It's a SD1000H, 100w from 2x 6550 output tubes. I used to have an Artist combo, basically the same amp with 4x 6L6, and absolutely loved the clean channel on it. Stupidly sold it. I bought this head a couple years ago wanting to get that clean channel sound back. Turns out the head had issues. The circuit board was wonky. Someone had tried modding the amp and had cut circuit traces, resoldered parts with too much heat causing the some of the pads to lift off the board, all kinds of stuff. Also, the channel-switching relays never worked right. I think their power source got messed up or something. And unfortunately, the amp would not stay on the clean channel, only the OD channel.

I made it a project over this Christmas. I gutted the amp to a bare chassis and rebuilt the clean channel using a hand-wired tagboard and a layout I designed myself. I recreated the original circuit but used good parts. It turned out great! I found out the clean channel on these amps is very similar to some vintage Ampeg designs. That would explain the big fat gorgeous clean sound. Dennis Kager who built the Sundowns, used to work at Ampeg (along with Ken "Trainwreck" Fischer), so I guess it's no surprise with the Ampeg lineage.

So I've got me a kinda/sorta 100w Ampeg :D Gorgeous cleans, takes pedals really well, cranks into a moderately gritty OD by itself.

Here's some pics of the work I did. Went from this (note the preamp tubes mounted to the circuit board):

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To this:

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Re: Duncan Convertible amp question

Yeah, they're hidden gems. You can still get them pretty reasonably on eBay, but they've been going up. I got my head a couple years ago for $300. They're going for $5-600 now. Of course, they probably work :butkick:
 
Re: Duncan Convertible amp question

ALF I didn't know you had those skills. I just purchased a Blackheart 5 watt and got the Mojo kit to do a handwired board with rectifier tube and although it was fun I have no desire to do a larger project. Congrates on your work.
 
Re: Duncan Convertible amp question

Wow, thats impressive. How hard is it to make up a schematic from scratch. I have an old tube amp that I'll need a schematic for in order for the dudes on seawatt to better understand whats up?
 
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