• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Tube amp help

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I've just managed to bag myself a few NOS valves from someone I know and wondered if anyone could advise on possible headphone applications for them

These are what I have

EL86 (3 off)
ECC82 12AU7 (1 OFF) I've seen a few designs using one of these
PL508 (2 off).

Any help would be very much appreciated
 
You could build a simple single-ended OTL like this one with ECC82 and 2x EL86, for example. (This one is so simple it doesn't even have any gate stoppers. I'd want to check stability in practice.) Obviously it would be mostly for mid-high impedance cans (>100 ohms or so), and certainly not for ones known to be fussy about low output impedance or very sensitive ones that would make every last bit of noise heard, and I would normally prefer a more advanced topology. It'll also generate its share of heat (about 17 W in total for heating + idle currents). But it should work.
 
Thanks for the quick response, I'll certainly take a look at it, I'm trying to get back into building things, so I don't mind trying a variety of options to get something I'm truely happy with.

You are starting this project backwards. The value of the tubes is minor compared to the cost of the entire unit you want to build. You should decide what you want from a headphone amp and build the right circuit with whatever tubes it needs. Sell what you have to fund what you really want or keep them for another project. Don't build an amp around the tubes you have unless by luck they just happen to fit a great amp circuit. G'Luck! 20
 
Thanks for the input 20to20, I see your point for sure, I only bought the box of tubes because I wanted the ECC82 for a project and I got such a good deal on them as a bundle. I've got no problem selling on the tubes to get something more appropriate, but I just wondered if there was anything that could be done with the ones I have already.
 
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