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Old 17th Sep 2017, 10:17 am   #241
Diabolical Artificer
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Default Re: 807 (maybe) amplifier build. Now EL34

Here's the schematics for the amplifier. There is the odd drawing mistake.

Thankyou Joe, your appreciation/support is welcome.

Am aware of inefficiency of speakers David, the weak ling in the audio chain, or one of em.

Thanks for pointers Chris, I'll tackle it one day in the week.

I've personally found that after about a watt or so, my ears can't really detect any incremental increase in loudness. The main joy of listening to loud music is the bass hitting you in the guts, turning your diapragm into a driver of sorts. I end up with a girt big silly grin on my mush for some odd reason. Maybe this is an atavistic reaction to do with drums.

Anyhoo, I digress. Re, the amp etc circuits; any thoughts, comments or constructive criticism welcome.

Andy.
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Old 17th Sep 2017, 10:54 am   #242
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Default Re: 807 (maybe) amplifier build. Now EL34

I have the schematics as a Docx file which is too big to upload here. If you want it drop us a PM with your email address, and I'll send it to you.

A.
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Old 17th Sep 2017, 12:42 pm   #243
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Default Re: 807 (maybe) amplifier build. Now EL34

A few notes on the PSU schematic. The voltage at the tap on the cathode follower htr supply is 200v. Oh and there are 0.1u caps accross the 12.6v htr supply, bias supply bridge rectifiers to stop switching noise. Same as on the HT supply BR's. The "symbol is a conflation of a BR and N suppression caps.

A.
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Old 18th Sep 2017, 12:24 am   #244
joebog1
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Default Re: 807 (maybe) amplifier build. Now EL34

Hmm I think 18.9 volts for 2 X EL34 is a bit high too!! Maybe you mean 3X EL34 ??

best regards
Joe
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Old 19th Sep 2017, 8:10 am   #245
Diabolical Artificer
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Default Re: 807 (maybe) amplifier build. Now EL34

That's 2 x 18.9v for six EL34's Joe, three each side.

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