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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

Small tube amp for headphones/computer speakers?(first post)

caveman24

Member
2008-03-15 6:46 pm
Hi, im new here, verry interested in hifi, and tube amps in particular for there nice full warm tone. I have a couple of old all tube radios from the 40's, and they sound better than any of the crap you can get at department stores. I have done a lot of research into tube amp home brew. im quite skilled with a soldering iron, comes from may years in the ham radio scene, building homemade radios, etc. I was wondering if there was any easy suggestions out there for a simple small .5 -1 watt SET amp suitable for driving headphones or small speakers, Im looking for a design that is easily transportable, possibly even battery powered (Is there even a remote possibility of a tube amp that will run on a few AA's for a long time? or even solar power?) Thats probably a longshot so I'll settle for plug in if I have to. Im open to any suggestions.


peace!
 

rman

Member
2007-10-09 4:16 am
Hi.

My first tube project, (out of a whopping two) is a copy of Garry
Kaufman's 6em7 direct coupled amp. It puts out a little over one watt and sounds great. Theese tubes although out of production,
are cheap and plentiful. I used Edcor xse 15-8-5k output transformers wich cost about $20 each. More power could be sqeazed out of this tube, but the operating points and loadlines of the design as is is quite linear and really does sound good. Best of all, it is simple and easy to build. My chassis plate measures about 10"" * 15" But I suppose you could make it a
bit smaller if you really try. I think it would would be quite a challenge to build a battery powered tube power amp that could be called hi-fi.

This is Garyy's page for that amp
http://the-planet.org/6EM7.html

Enjoy.
Rolf
 

caveman24

Member
2008-03-15 6:46 pm
Thanks for the info, ill look into some of those. I found this online after doing a lil google search:

http://cgi.ebay.com/Brand-New-Vacuu...ken-Japan_W0QQitemZ140214087846QQcmdZViewItem

It looks real cheap in the quality department, and those speakers cant be anything but awful, but there just standard connector so you dont have to use those anyway. It definately meets my power requirements. I Might get one of those to experament with and see how they managed to get tubes powered up on 2 D cells. study the circuit a lil and see if I can come up with something better, possibly even smaller. I manly want to just see how they are driving the b+ off only 3v and apply it to more commonly available tubes, some kind of power converter?

I am really curious how they pulled it off. who knows, the tubes might just be for looks and theres really a solid state amp in there??? Hope not, thats false advertising. Ebay cant be trusted anyway.

thanks for the replies

PEACE!