Twin Conversion

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geekmacdaddy
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Twin Conversion

Post by geekmacdaddy »

Newb Question;
Can a Twin be converted into an ODS? What would it take? What could I keep?

Thanks
Geek
'67_Plexi
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Re: Twin Conversion

Post by '67_Plexi »

Done that one. Converted a Twin to a HRM.

Depending on the year of twin, the power transformer seems good for both EL34 and 6L6 models. The ouput tranny is good if you opt for an older non HRM, otherwise you'll need a new one. You can use the cap can, just replace the caps and resistors with the correct values. The fibre boards can be stripped of components and reused, although I would recommend making new ones from Garolite.
With all the real estate, getting everything in is real easy and I even chose to put the tone controls for the OD on the front panel as well as build in a Dumbelator. Overall a very good donor. Oh...you'll proabably want to replace the speakers to.

Pic of mine attached.

Regards, Alan.
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jaysg
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Re: Twin Conversion

Post by jaysg »

I'd stick with 6L6's or get a Series II Twin and replace the OT.
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geekmacdaddy
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Re: Twin Conversion

Post by geekmacdaddy »

thank you guys. any thoughts on this are appreciated.
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Bob-I
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Re: Twin Conversion

Post by Bob-I »

'67_Plexi wrote: The ouput tranny is good if you opt for an older non HRM, otherwise you'll need a new one.
Why the OT replacement?
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jaysg
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Re: Twin Conversion

Post by jaysg »

Bob-I wrote:Why the OT replacement?
HRM models...treading on thin ice...are EL-34 amps and HAD built them with Plexi OTs. Traditionally...non-HRM are 6L6 amps. Sort of brings up the question of what design/features/output tubes were used on the amps he built with Music Man HD-130 iron.

My suggestion to replace the OT is specific to the Series II. My Concert had a good clean tone and an iffy overdriven tone on the clean channel with 6L6s.
Last edited by jaysg on Tue Aug 22, 2006 3:30 am, edited 1 time in total.
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geekmacdaddy
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Re: Twin Conversion

Post by geekmacdaddy »

nuther question;
What could be used from a Peavey classic 50 212 donor? Bob-I?

Thanks
Geek
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geekmacdaddy
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Re: Twin Conversion

Post by geekmacdaddy »

'67_Plexi wrote:Done that one. Converted a Twin to a HRM.

Depending on the year of twin, the power transformer seems good for both EL34 and 6L6 models. The ouput tranny is good if you opt for an older non HRM, otherwise you'll need a new one. You can use the cap can, just replace the caps and resistors with the correct values. The fibre boards can be stripped of components and reused, although I would recommend making new ones from Garolite.
With all the real estate, getting everything in is real easy and I even chose to put the tone controls for the OD on the front panel as well as build in a Dumbelator. Overall a very good donor. Oh...you'll proabably want to replace the speakers to.

Pic of mine attached.

Regards, Alan.

Stunning looking, Alan!
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Bob-I
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Re: Twin Conversion

Post by Bob-I »

geekmacdaddy wrote:nuther question;
What could be used from a Peavey classic 50 212 donor? Bob-I?

Thanks
Geek
The iron, the chassis, power switches and the output tube sockets.

I have a full layout of the HRM with 6L6's done, sounds great but there's a little hum that I just can't get rid of. My guess is that it's from the cheepy PT.

I wish I had the cabinet with the 2x12, I think it would be a great "sleeper". A cheezy old Peavey that sounds like a Dumble. :wink:
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geekmacdaddy
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Re: Twin Conversion

Post by geekmacdaddy »

Thanks Bob
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Bob-I
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Re: Twin Conversion

Post by Bob-I »

geekmacdaddy wrote:Thanks Bob
Wait... let's make sure we're talking about the same amp. Peavey had a ton of amps called "Classic". Mine is an SS preamp and 2x6L6 output. If you're talking about the 4xEL-84 you've got a lot more work to do.
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geekmacdaddy
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Re: Twin Conversion

Post by geekmacdaddy »

yepper...EL84's. not the "classic". the Classic 50 which came as a 4 10 and a 2 12....
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Bob-I
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Re: Twin Conversion

Post by Bob-I »

geekmacdaddy wrote:yepper...EL84's. not the "classic". the Classic 50 which came as a 4 10 and a 2 12....
I have a Classic 30 chassis that I built a Marshall 18 watt into. The ONLY thing I could use was the PT, and even then I had to add a filament xformer. These are odd layouts, with the controls directly above the tube sockets I have lots of oscillation issues with it.
'67_Plexi
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Re: Twin Conversion

Post by '67_Plexi »

You won't gain anything by using a Classic 30 chassis. They are made on a wicked budget (although do sound OK), the transformers are cheap and cheerful and there is really not too much room in the chassis for neatly placing the boards etc. Plus the tube sockets are mounted on the circuit board. You'll end up with a nightmare and wished you just kept the C30.

Sometimes building from scratch can end up not costing that much more than using a donor and even less if you use an unsuitable donor..

The Twin or a lot of the other SF Fenders will make an OK donor with less hassle than most. There are a few budget amps like the Sundowns that have decent transformers and are built in a chassis that's pretty good for a Hybrid A based build with 6L6's. You can even build a reverb version in these without too much trouble.

Still it's much more fulfilling to design and build your own variation from scratch.
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