Entry level valve amps?

[carboncomp]

Anyone got any links to good projects with entry level valve amps?

[geertjacobs]

http://www.ax84.com/p1.html

Be sure to read the Theory document. Very interesting.

BTW: a cheap starting point for your tube amp adventures is a used Epiphone Valve Junior. Very similar to a P1.

[amptramp]

A lot of old tube radios had a phono input jack which is connected directly to the amplifier.  There is usually a triode voltage amp followed by a pentode or beam power output.  My daughter's favourite guitar amp is a 1938 Minerva radio that I restored to working condition which has a single triode connected to a push-pull output using a single plate to push-pull grid transformer.  There were also some tube record players.  These will be similar to a guitar amp but may have better bass response.  You can add a tone stack to the voltage amp stage.  You can download the free tonestack calculator here:

http://www.duncanamps.com/tsc/index.html

[defaced]

I offer one word of caution about old radios/phono players/etc.  Many old tube electronics either don't have a power transformer or use a two prong plug and a death cap - both are very dangerous and will need to be updated to modern power transformer and three pronged plug to be safe to use.  None of those issues are insurmountable, but if you don't know about them, you can seriously hurt/kill yourself. 

As for projects, AX84 probably has the largest selection of basic intro tube circuits for guitar.  For theory/help/reference, I learned most of what I know from:
http://www.music-electronics-forum.com
http://www.aikenamps.com/TechInfo_2.htm
http://www.freewebs.com/valvewizard/
http://www.ampbooks.com/
http://www.webphix.com/schematic%20heaven/www.schematicheaven.com/index_HTML.html

[tubelectron]

My daughter's favourite guitar amp is a 1938 Minerva

Absolu Sacrilège !!!

Anyone got any links to good projects with entry level valve amps?

Have a look to the good old Fender Champ and its derivative... Moreover, you will find it in kit version at an affordable price !

A+!

[arawn]

Epi valve junior, fender champ, Bugera V5, little giant, all good, sound good etc. I have the bugera and its real bluesy, but with hb and the gain dimed it does a respectable metal sound.

[amptramp]

Defaced is correct, the amp should have a power transformer and the one I am referring to does.

Tubelectron, the amp has been an instant favourite of anyone who has listened to it and I am including at least one professional musician who works in a music instrument store when he is not on a gig, so he knows the state of the art.  The 12" electrodynamic speaker in the radio (this is a floor-standing console) is good for guitar or bass.  The circuit is a 6C5 driving a pair of 6F6G's in push-pull through a splitter transformer that is capacitively coupled to the 6C5 to avoid DC saturation in the transformer primary.  The 6F6's are good for 11 watts and with the output transformer mounted on the speaker, damping is excellent and the losses from speaker cabling are nonexistent.  It has one switch for bass boost and one variable treble control.  The phono input is a 1/4" jack, not a phono jack, so the guitar cord plugs right in.

[boogietone]

Doug's Firefly is a good one with which to start. The ax84 site has a forum concerning it.

[petemoore]

  It's simple once all the complications are sorted out...
   Which might take a while, recommended pre-reads, reads and even re-reads...
  Power Supply requires mains wiring as well as B+ wiring, most of us who have played around with tubes at low voltage and high voltage lean toward high voltage...even though there are amplifiers which output to speaker using only 12vdc supply [see Cadillac Radio, low voltage tubes].
   Grounding [star ground requires a few more wires than a reduced wire grounding scheme, otherwise simplifying the 'solid groundings' matters.
    Tubes really do wire up a lot like a Jfet or other active circuit once all the needs have been met.
   But understanding load lines and other tube-stuff to really get the amp to purr...allows the builder to know how important it is [or not]. Just following a tried/true method and circuit works though.
  ...much the same as learning electronics @ low voltage, but high voltage = high tension [dangerous to work with, also has greater propensity for create inductances and cross-talk]. So...more 'stuff' to be aware of.
  AX84 and other amp-sites are really required reading for a newbie tube amplifier ponderer who wants excellent amp without a whole lot of hair-pulling and missed sleep.
   Take your time ! Plan it out ! Always prethink safety issues... Good Luck ! ! !
  Don't even start until it is well understood what B+ is, how to drain and check the voltage of the filtercaps...every time,  just as important to unplug the AC...make sure there is no AC or DC potential in the amp before entering ! !