One day i was looking around the internet for little practice amps with tube preamps. I saw the ruby tubey (but that has too many parts) and i also saw the tube cricket but i could not find a schematic. then i remembered seeing something about a tube boost that runs on 9v called the valve caster.(in case you dont know you can find that here: http://www.diystompboxes.com/smfforum/index.php?topic=63479.0 (http://www.diystompboxes.com/smfforum/index.php?topic=63479.0)
anyway that gave me an idea for a little practice amp like a ruby or noisy cricket. replace the fet input thing (not sure of the propper name) with a valve caster circuit running into the input of an lm386 power amp. Ill post a schem later
my question to you is do you thing this will work.
in advance thanks for the help.
QuoteIll post a schem later
my question to you is do you thing this will work.
Who knows? :)
Post the schematic !! ;)
Sounds do-able to me.
schematic attatched :tu:
I don't know if there is anything to it or not, but I've heard that 12AU7's don't sound too well with anything less than a 48V supply. I haven't tried to find out, though. I've got a 12au7, but I might save that for a firefly amp. The real magic with the ruby type amps is the way the LM386's sound when overdriven. Probably might as well stick with fets or op-amps. Of course, there is one way to find out for sure. :)
im ordering the parts tommorow ill post again when its done. :tu: but i only have a 12ax7 and the 12au7 has to come from england so that might take a while.
Quotethe 12au7 has to come from england
Well, that doesn't mean too much because we don't know where *you* live.
You might be as close as Jersey and Guernsey or as far as Marambio Base in Antarctica or the middle of Gobi Desert !!! :lmao:
His user profile says New Zealand.
It's a small crazy world indeed !!! :o :D ;D ;) :loco
Looks like you're re-creating the Tube Cricket. Here's a link to a discussion forum with the schematic. I have a Valvecaster running at 12.6V that I really like...I have not tried bridging it to a 386 yet.
http://www.diystompboxes.com/smfforum/index.php?topic=66623.0
thanks for the info, Ive almost finished my prototype just gotta build a power supply and then it should be done. i didn't use an 386 because none of the ones i can find work properly, so i used some car amplifier chip amp kit its about 11.5 watts amp sounds pretty good with just the guitar plugged straight in to it.
Hey, did you ever get this wired up and working? I've had it in my head to do the same sort of thing for a while now... I've got all the parts sitting around, but wanted to see if someone else had made this work (and what it sounds like!) before i give it a go...
when i tried it with a 12ax7 it didn't really sound very good, so i built a fetzer valve instead and it sounds much better. You could try it with a 12au7 and see what it sounds like.
Thanks for the response. Yeah, the fetzer valve is a neat circuit. Easy to slap together and sounds so good! Interesting that it sounds better than a space-charged 12ax7... I do have some 12au7's sitting around, so I might give that a try one day, but I'd have to order some tube sockets, and I'm lazy!
Quote from: darwindeathcat on October 13, 2011, 05:18:03 PM...but I'd have to order some tube sockets, and I'm lazy!
Heck, at least you're honest!
Quote from: dan6896 on January 23, 2011, 02:55:23 AM
One day i was looking around the internet for little practice amps with tube
my question to you is do you thing this will work.
in advance thanks for the help.
Just change stock tube to 12AU7 in my Micro Terror. Now sounds more tweedy, not so harsh as original, but still an Orange type of sound.