How to make REALLY simple tube pedal?

[Electricblue]

Ok, I would like to get into tubes a bit.

Is there a REALLY simple tube circuit out there somewhere?

By simple, I was thinking two wires from the input to the tube, and two wires from the tube to the output, and maybe a battery attached or something. However, I dont know if its that simple.

Im not looking to overdrive it or anything, just want to have a tube in my rig

Thanks guys.

EDIT: I would rather not use 300v voltages in there etc. I think thats called a starved plate or something? I'm new to tubes.

[BruceBass3901]

I think the Beavis Audio website has some simple tube circuits on there. Try looking there

[Electricblue]

Originally Posted by BruceBass3901

I think the Beavis Audio website has some simple tube circuits on there. Try looking there

I'm on it

[pig]

Search for the schematic for the valve caster. Its the simplest one I've come across. There are no tube pedals that are as simple as input-wire-tube-wire-output. You need at least a few resistors and caps. Possibly a diode or 2. Good luck.

[Electricblue]

Originally Posted by Electricblue

I'm on it

Ok, I had a look at the valvecaster circuit, still does seem a wee bit complicated for my noobness.

I was thinking dead simple, no adjustables or anything. I'm really crap when it comes to schematics with more than 10 components

[Von Felgenhauer]

You might want to start on some simple fuzz pedals first to understand the schematics and how to wire everything up.

[MuzikMan]

Originally Posted by Von Felgenhauer

You might want to start on some simple fuzz pedals first to understand the schematics and how to wire everything up.

+1. I think a DOD 250 / MXR Distortion+ clone is a great first pedal build.

[Electricblue]

Ok, I'm pretty sold on the valvecaster. I found this schematic, is there any way to eliminate at least 2 of the pots, both for simplicity and cost? I wouldnt mind keeping the gain if possible.

Could I swap the pots for resistors of the same value, and solder the (what would go to the centre tag) to one end of the resistor, Leaving the pot all the way open?

Sorry the image didnt work. Its the 4th one down on this page.

[MuzikMan]

Wiring pots is not difficult and they are not expensive. You definitely should not be altering proven designs until you get to know a little bit about what the stuff does. Do yourself a favor and follow the plan until you can truly understand what all of the components are doing.

[doomdude]

Originally Posted by Electricblue

Im not looking to overdrive it or anything, just want to have a tube in my rig

If you just want a tube in your rig, you can buy a cheapish tube preamp like this one
PRESONUS TUBEPRE - Thomann UK Cyberstore

I have no idea about making your own, but I would just buy this one!

[Electricblue]

Originally Posted by doomdude

If you just want a tube in your rig, you can buy a cheapish tube preamp like this one
PRESONUS TUBEPRE - Thomann UK Cyberstore

I have no idea about making your own, but I would just buy this one!

The idea was to have it as a project to enjoy building but cheers anyway dude.

[Downunderwonder]

Go to diystompboxes.com they have a huge forum for this stuff and a megathread on valvecasters. Find the "vero" layout, pots are cheap, it's only the valve itself that is really pricey.

If you got really creative you could ramp up the operating volts and it would become a preamp. Maybe not on a first build but you could keep that in mind when ordering your resistors and capacitors to get the high voltage ones.

[Testing_123]

+1 on the Valvecaster suggestion -- that's as easy as it gets for a tube circuit.

Don't let the potentiometers in that circuit intimidate you -- they're easy to wire.

Might be a good suggestion to try another circuit first, however. Look at Small Bear Electronics Tweak-o, or some of the projects from General Guitar Gadgets or Tonepad.

[arginator]

So did you end up building the Valvecaster? I'm curious about how this would sound with bass.

[vin*tone]

There are a couple of circuits around for 'space charge' tubes - which are designed to run on 12 volts (originally for car radios).

A great first project is the Flipster. It's not a tube amp but is a OD pedal based on the B15 Pre Schematic.

[runmikeyrun]

A valvecaster won't play well with an active bass, I found that out the hard way. Very, very splattery and no amount of experimentation would get rid of it.

If you have a passive bass, these are great. They get sort of fuzzy at max gain settings, and if you want more distortion you can adjust the plate resistors or add cathode bypass caps. I also built a twincaster, which is two valvecasters in series (the second valvecaster does not need a gain control). It will get a great overdrive all the way to almost a distortion. You really don't need a tone control, but just be advised they get a little dark when they start to overdrive.

This is a link to the valvecaster thread. I highly suggest you read ALL of it (even though there are a million pages) because there are a lot of revisions, tips for better sound, and best of all, troubleshooting. Make sure you print out the list of what the correct voltages are on all the pins, that way if there's a problem you can check your voltages and figure it out.

Tube boost + overdrive running off a 9 volt battery

It is about the simplest tube circuit you can get. One word of advice- you need an extremely clean source of DC for the power supply or you'll get a lot of hum. the only kind of power supply I found that was clean enough was from an old lap top. You can find laptop power supplies at thrift stores for a couple bucks or used on ebay.

The simplest way to power this is with a 12v supply. That way you won't need to build a separate voltage regulator circuit to run the tube heaters. I'll admit the circuit does sound better at 18-24v but if you're not very experienced with electronics then you don't want to have to worry about the extra circuitry for a voltage regulator, or getting rid of the hum from it.

One last note- the valvecaster IS sensitive to tube changes. contrary to popular belief, some circuits, even though they are "starved plate" designs, do sound different with different tubes. I had some NOS Sylvanias that sounded the best, but i'm sure JJs would sound good for new production. Call Bob at Eurotubes and tell him you're running 12AU7 at 12v and ask him if it will operate properly. Someone on DIYstompboxes said a JJ 12AU7 didn't work out well because of some sort of specs on them.

Good luck! someday I might build that Triplecaster... or maybe a Quadcaster...!

[arginator]

[quote="runmikeyrun"]A valvecaster won't play well with an active bass, I found that out the hard way. Very, very splattery and no amount of experimentation would get rid of it.


Anyone know how to fix this? I'd like to build one of these, but I play an active bass.

[Dazonbass]

PYPB XXXIII - Effects are STOOPID

scroll to the bottom of this, it appears that because it appears that Jimmy rocket had some luck with this. Maybe you could ask him how he modified it.

Goodluck