EF80 Micro ???

TonyTele63

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I've been interested in building an EF 80 Micro amp for a few months now and in an overkill moment I ordered five (yes five!) Antec AS-05T200's from the US. The first of these will be used in a EF80 Micro Champ project as this seems like a good place to start my amp building learning curve. I'm also interested in building EF80 Micro Bassman at some point so thought I would order the parts for both at the same time but after this I still have three PT's. What other amp projects would you recommend to use these on?

I'll be building both of these projects as heads (I'm a sheet metal worker so have a couple of ideas about the housing) and I'll need a speaker cabinet. Are there any good sites/reading on building a 1x12? It'd be nice if I could build something that would handle a higher wattage amp (max 20 watt-ish) just incase I get the bug and build something for outside the house.

Thanks for any advice
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King Fan

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Always interested in these EF80 Micros, especially with toroid PT. Share everything you learn!!!
 

SerpentRuss

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5 of them? Hmmm...OK, LOL

You're looking at a max of ~260 volts with a solid state rectifier and light loading. I have one of these in a 4-watt amp with a 6P1P (Russian 9-pin 6v6-ish) single-ended output. It sounds pretty good but's not crystal clean. If you've ever studied the lines on tubes with a reactive load, you'll find that running a lower voltage often puts you in a range of operation that yields a bit more harmonic distortion.

If it were me, I might have purchased a voltage assortment in that 50 VA size. That said, there are likely a lot of small projects this size PT would be good for. I would think a nice Champ-ish build would be a candidate. Maybe something like a Harvard with 6AK6 output valves. Projects with push-pull architecture will have less expensive output transformers.


EDIT: Just realized you're in the UK, so you'll be wiring to 230, correct?
 
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pavel

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Sorry, don't have advice on cab building specific to an EF80 micro -- I am close to start on a micro JCM800 EF80 and was going to stay small, perhaps try an 8" Celestion.

I do want to add a AC voltage switch to my build though, because even though I am US based, you know, one of these days I'll be touring for sure, I'll be traveling the world and need all the configurations, right? :)

I'll be using one of these Voltage Selector, but I'll only wire the 110V and 220V or perhaps make the 220V and 230V setting be the same because the PT doesn't have a separate winding for the 10V difference.

I'd be curious how the Antec is working out for you with 230VAC.
 

TonyTele63

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Just realized you're in the UK, so you'll be wiring to 230, correct?

That is correct

5 of them? Hmmm...OK, LOL

You're looking at a max of ~260 volts with a solid state rectifier and light loading. I have one of these in a 4-watt amp with a 6P1P (Russian 9-pin 6v6-ish) single-ended output. It sounds pretty good but's not crystal clean. If you've ever studied the lines on tubes with a reactive load, you'll find that running a lower voltage often puts you in a range of operation that yields a bit more harmonic distortion.

If it were me, I might have purchased a voltage assortment in that 50 VA size. That said, there are likely a lot of small projects this size PT would be good for. I would think a nice Champ-ish build would be a candidate. Maybe something like a Harvard with 6AK6 output valves. Projects with push-pull architecture will have less expensive output transformers.


EDIT: Just realized you're in the UK, so you'll be wiring to 230, correct?
 




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