1-5w Valve Amp DIY?

nick

Right so I have one of these:

Which I bought from a forum member to steal the speaker out of ? but I plan to get my blackback repaired and then put it back in the cab. Basically Im toying with the idea of building a small 1-5w valve amp, nothing fancy, input, volume and tone. Want it to be clean when backed off on the guitar vol and dirty up when pushing the front end hard. The idea is it doesnt have to be loud at all, the girlfriend is quite keen to steal this from under me once Ive built it ?

http://www.ax84.com/

These guys offer plans to build, anyone else know of something simple like this? Comments? Ideas?

bottledtone

You can get 3 - 5 watts with a single ended EL84, or 6V6 or do the blackstar option of having 12AU7(1-2 watts) or 12BH7/ECC99(3 - 5 watts) push pull but then needing a phase inverter.
Then is also the idea of having a self slpit output without the phase inverter but then you'll have a drop in power and it sounds more single ended (like the mesa Singled ended switch)
Look for old schematics of champs for the single ended stuff. Or copy the Vox AC4TV which has attenuator built in 1/4watt, 1watt and 4watt. Blackstar hasn't got a valve phase inverter(but they still call it full valve? :? but the little push pull would be a cool option. It what i'm building at the moment ?
there are quite a lot of options.
with the lower power there isn't that much clean headroom, but still get loud distorted tones ?

MikeM

I'd suggest a simple circut like the 5F1 with voltage scaling. Output tube and tonestack of your choice, most are pretty easy to shoe-horn in.

rikus

Nick, seeing as we're both in Durbanville, if you're interested in a fender champ type amp (single ended class A 6v6 type) you're welcome to come and try my tweed princeton (5f2a circuit) clone... I can also switch out the tonestack to turn it into a tweed champ (5f1 circuit).

R.

nick

rikus wrote: Nick, seeing as we're both in Durbanville, if you're interested in a fender champ type amp (single ended class A 6v6 type) you're welcome to come and try my tweed princeton (5f2a circuit) clone... I can also switch out the tonestack to turn it into a tweed champ (5f1 circuit).

R.

Would love to run that through my 2x12" Greenback'd cab at some point 8)

rikus

nick wrote: Would love to run that through my 2x12" Greenback'd cab at some point 8)

YES!!!! I'd also love to hear that!

Wizard

What exactly does "single-ended" actually mean?

rikus

Wizard wrote: What exactly does "single-ended" actually mean?

Single ended means there is 1 valve handling all the signal all the time.

The opposite of single ended is push-pull, where you have two valves operating together, but out of phase (in one tube the signal will be /\ while in the other it is \/), to provide single output signal.

I'll leave it to the real guru's to correct and/or expand. ?

Dave-W

Have a look for the ax84 october 2W version it sounds amazing but its not on their active list on ax84 anymore you have to search around for it a bit, you can listen to clips on www.chappellamps.com

Gearhead

One of the best explanations about 'single ended' can be found on the Mesa website under articles. Talk about tube guru's...