Add Headphone out to guitar amp

[Bob M.]

I've been asked to add a headphone out on a Twin Reverb amp by an apartment dweller who is being considerate of his neighbors. I'm wondering if I could standby the power amp and get enough wattage from the preamp and /or reverb driver to drive a set of headphones. Does anyone know of a good circuit for headphones that can be adapted to a MI amp? Years ago I had an amp with a giant power resistor taking the amp's output but it seemed like a really inelegant solution to the headphone thing (but it worked good). Any comments would be appreciated.

Thanks,

Bob

[52 Bill]

I don't think that the customer would be very happy with the output from the reverb driver as it is greatly high pass filtered by the 500pf cap to it's input. I'd suggest a outboard box with a built in load resistor and headphone jack, that way there would be no change to the amp itself. It could even be switchable in or out of circuit when the owner wanted to play through the speakers.

[Sweetfinger]

Good grief! You can buy a used line 6 Pod for a hundred bucks and it's going to sound much MUCH better than a twin with a headphone out. That's pretty much the ONLY thing the Line 6 stuff is good for IMO, bedroom jammin!

What's the customer's expectations? Do they want a full cranked sound, only in the headphones? A Headphone out on a twin isn't going to deliver any sort of good 'cranked' tone without some tone shaping. If they only have the ONE amp, and need a headphone out, but don't need an overdriven sound, just do it the 'old coot' way, and plug the headphones right into the speaker jack. Of course, you have to really WATCH the volume, or you'll go through a lot of headphones.

They're probably going to immediately hook the headphone out into their soundcard and try to record some of that great tone.

I'm just serving up a coupla plates of food for thought. Really, there isn't any reason these days to put a headphone out on any high powered amplifier because there are so many different, cheap, elegant, great sounding alternatives that get you to the desired destination. OTOH the customer isn't always right, but the customer is KING!

[Enzo]

Exactly my thoughts. For the money they would have to pay you for this, they might as well just get a practice headphone thing like the Pod, or a V-amp, or an old Sholtz Rockman, etc. or any small SS amp with phones jack.

Not only that, but with something tiny and portable, he can play it in any room he likes, without having to lug the big heavy Twin all over - silent or no.

As to the Twin, if it is in standby, there is no B+ in ANY of the circuits. SO there is no way without major rewire to have the preamp running without the power amp.

You COULD wire all the power tube cathodes together and add a switch between them and ground. Then opening the switch will turn the power tubes tubes off.

But if you are looking for the power tube output signal without a speaker, it won't be simple, you pretty much have to have a dummy load

[Bob M.]

Well this is how I've done it in past, with a dummy load, but I thought possibly someone clever has marched into the future with some new ideas. I know a twin isn't the best bedroom amp but that's what the guy has and he's not getting rid of it. He doesn't really want to buy any extra gizmos (although he should). I asked because he's a prince of a guy. It just seems like such a standard feature on newer amps today that possible it was an easy implementation.

Thanks for your feedback,

Bob M.