Tube boost + overdrive running off a 9 volt battery

[karter2000]

Okay, I just breadboarded a basic Valvecaster (no tone) with a 12at7 (only one I had around).  I have to say, this thing sounds excellent with bass guitar.  Initially I tried it at 9v, but soon switched it to 12v (sounded better to me).  Not lots overdrive, but a nice low-gain growl.  Not sure if I need much more overdrive than it produces anyway.  Definitely lots of volume available.  Can't wait to try it with a 12au7.

Now I'm hooked!  The tube I'm using is glowing quite bright...soooo cool!

[Dongle]

Just want to say, that my valve caster is also working now. I think the problem was a broken cap...
Thank you Renegadrain for your help!

[Renegadrian]

@Ripthorn
Nice to see you back, man! I love how this project still catches attention, and some newcomers are now in the topic.
You're definitely right about that!!!
@Karter2000
Yes, I do think that an AT7 in the Valvy gives that extra kick, and yeah it's good on bass!!! It "rounds" and fattens the tone in a "pure" way. Post pics when you're done with it, right?!
@Dongle
Nice to read you made it, man!!! Glad if I helped you somehow...Enjoy!!!

[karter2000]

Totally tube noob question, but how do you guys mount the tube socket in the enclosure?  I've looked through the thread, but I'm still confused.  I'm using a chassis mount tube socket.

Thanks!

[CynicalMan]

Totally tube noob question, but how do you guys mount the tube socket in the enclosure?  I've looked through the thread, but I'm still confused.  I'm using a chassis mount tube socket.

Thanks!

Chassis mount sockets have a diamond-shaped plate around the socket with holes in the sides. You mount the socket using a nut and screw going through these holes and corresponding holes in the enclosure. You can see the screws in this pic beside the base of the tubes.

[Dongle]

As I told you before, my valvacaster is working now - with 9 V and I like it!

But: Is there a possibility to get more volume? I guess, with 12 V it would be a bit louder, but is there also another possibility?

[Dongle]

What would happen if I lower the 100k resistor R3 and the 220k resistor R2? I thought, I might get higher voltage at the Anodes -> more volume?! Is this true? What disadvanteges do I get, if I would do it?

[zambo]

I believe you will get more volume and clean headroom. If you go to the homepage and look at tube amp stuff > tubes for dummies you will find a lot of helpful stuff there. It explains all of the resistors and caps as well as cathode bypass caps and plate resistor bypass caps for rooling of highs lows etc. Very cool stuff and it has been invaluable for me. If you build pne of these then you will probably build two. Then you are going to want more gain etc. That page will help you a lot. And yes nore voltage = more volume in my experience ( wich isnt a lot ) 

[tombola]

I thought you'd all enjoy some Valvecaster pr0n - my 12AU7 running 12v, got it up and running very quickly after reading this entire topic. Cozy! (NB: It's a 1 minute exposure...)

Glowing valve / tube by Tom.Whitwell, on Flickr

[Dongle]

I just found an old 12 V supply and will test it later this day... I am looking forward to it - especially, because I already like it with 9 v...

[antiuser]

Wondering if anyone here can help me with this project... I built it on the bredboard and noticed that the status LED I put in turned off as soon as I made the connection between pin 5 and +12v. When testing the tube (-v to pin 4, +v to pin 5) with my multimeter connected to the bredboard I notice the voltage dips from 12.28v to 0.68v when the tube is connected (like a short). No glow. Tested 3 different tubes, all of which were working perfectly fine in my guitar amp. WTF am I doing wrong?

[zambo]

is pin 9 hooked up? if so un hook it...
did you use a schematic like renegadrians? If not try his. His stuff is pretty bulletproof

[antiuser]

No, like I said I was testing it only with pins 4 and 5. Nothing else was connected anywhere.
I tried with a different power adapter and it worked, I wonder why the hell the regulated one didn't.

[Dongle]

Sounds like your supply is not strong enough or you have a "wrong connection" - sorry, dont know the english word.. maybe "short circuit"??

[antiuser]

It LOOKS like a short, but the power supply works with everything else I plug it into. It's 12v, 1.5A, should be more than strong enough to power the valvecaster, no?

[zambo]

valvecaster will run on as little as 9v 200ma so yes. I believe heaters pull 150ma and plates are under 10ma

[Kain]

Just wanted to say that I built my first one yesterday, rock'n'roll. Thank you everybody for this super thread.

[oneeyedog]

Hi folks, 1st post.... 1st problem!!!! Just built this box, 1st attempt at any such venture! It does work but there is a loud hum from it, which increases dramatically with volume... I've checked and everything looks ok but obviously I've boobed somewhere.... any suggestions?
john
www.oneeyedog.co.uk

[zambo]

Try a different power supply. They will cause a mean hum! I use a 1 spot 9 volt. They seem to be consistently good.

[Renegadrian]

oneeyedog
You should get better result with a regulated PS, or regulate it using a 7812 - I got an image on my gallery and also was posted a couple of pages ago. It should help you to get rid of the hiss!!!
Kain
Glad you made it! Pics, please!!!
antiuser
grab the first scrap piece of vero and throw it togheter using my BULLETPROOF layout!!|