Help required to finish a valve project - please

If they glow, this is the place to be
Post Reply
Blues45
User
Posts: 13
Joined: Sun Nov 12, 2017 2:08 pm

Help required to finish a valve project - please

Post by Blues45 » Fri Feb 02, 2018 5:08 pm

Hi, Friend of mine had a go at building a Headphone Amplifier. He lives in London and I live in Oldham, Lancs - the amp is currently with me. It is built but has a couple of issues - one being MONO when it should be Stereo, and the other issue being HUM.

Any kind soul out there who might be able to assist????


Thanks.

RhythMick
User
Posts: 182
Joined: Fri Jun 23, 2017 12:24 pm

Re: Help required to finish a valve project - please

Post by RhythMick » Fri Feb 23, 2018 9:44 am

Is there a circuit diagram ?

How far did the build get ? Does the one channel work ?

Firebottle
User
Posts: 67
Joined: Mon Jul 21, 2014 7:50 am
Location: The Black Country

Re: Help required to finish a valve project - please

Post by Firebottle » Mon Apr 30, 2018 6:16 pm

Does the amplifier have floating heaters, i.e. no connection to the signal ground at all? This can cause hum issues.

If the output is in the form of a cathode follower then a raised bias voltage is probably necessary to avoid excess heater cathode voltages on all the valves.
Don't you just love valve phono stages 8)

Post Reply