Boob Tube (Valvecaster) Road Rage and Klon Buffer content

[juansolo]

As this has both a road rage and jimmybjj's Klon buffer I thought I'd post it here.

After building the Philcaster, it turned out so good that I decided to re-visit one of my old valve pedals. So this is my Danger: High Voltage pedal re-cycled into a more PC circuit.

I've gone for a single valve pedal as I still have my old Twincaster for double valve excess. What this has though is more grunt so it doesn't really clean up as well as the PC does.

So what's different? Well quite a few of the values are for a start to make this more simple than the much more tweakable PC. All the components are mounted directly to the socket to minimise noise from cables going backwards and forwards to the boards as with previous versions. The gain no-longer adjusts the bias of the valves, instead working between stages. Theres a buffer on the output and theres Madbean's Road Rage providing 15v to that, 23v to the plates and 12v to the heaters. It can take a variety of valves, but out of what we had, the NOS Brimar 12BH7 sounded best.

The results are stonking. This is the quietest valve pedal we've made so far and it pushes my new 6V6 MJW 5 watt amp (very clean) into pure AC/DC overdrive. It sounds glorious.

[Jimihendrix1987]

Awesome !!  

So you have mixed a Valvecaster with the Klon's buffer, haven't you? ...

What about the power supply? How are you powering this pedal? 9v AC? 12v DC?... Where did you take your layout?

Can you upload the layout you have been using? (i'm an electronic dummie, and I want to do this pedal exactly the way you have done... I'm sure it will sound Impressive)

THanks

[juansolo]

Awesome !!  

So you have mixed a Valvecaster with the Klon's buffer, haven't you? ...

What about the power supply? How are you powering this pedal? 9v AC? 12v DC?... Where did you take your layout?

Can you upload the layout you have been using? (i'm an electronic dummie, and I want to do this pedal exactly the way you have done... I'm sure it will sound Impressive)

THanks

It's 12vDC in. The layout is the Matusmin Valvecaster layout but with quite a few swapped values and the gain is wired differently. It's all scribbled on a piece of paper at the moment, I'll knock something together and post it up here with when I've done it.

[juansolo]

Cleggy (who's idea this pedal was, I just built it) has sent me the scribblage for what went into it. I'll do some sort of diagram thing for it at some point:

12V - pin 5 (heaters)
23V - through 120K resistor (R2) to pin 1 (anode 1)
23V - through 100K resistor (R3) to pin 6 (anode 2)
GND - pin 4 (heaters)

Input - 10nf cap (C1) to pin 2 (grid 1), 470K (R1) to ground

1.5K pin 3 (cathode 1) to ground
150n pin 3 (cathode 1) to ground (100n, 220n will be ok, just change amount of gain slightly)

1.5K pin 8 (cathode 2) to ground
150n pin 8 (cathode 2) to ground (100n, 220n will be ok, just change amount of gain slightly)

47n (C2) to pin 1 (anode 1 ), to Gain pot (100k) pin 3
Gain pot pin 1 to ground
Gain pot pin 2 to pin 7 (grid 2)

1uf (C3) to pin 6 (anode 2), to tone 1
Tone 2 to Vol 1 through 47n (C4) cap  (matches original vero, but different to the original schematic)
Tone 1 to Vol 3
Vol 2 to output

The Valvecaster schem for reference:

[Jimihendrix1987]

Thanks !!  

So, you are powering it with a 9vdc supply and This 9vdc goes into the Road Rage to get those 12vdc, aren't you?

So... If I use a 12vdc source, instead of a 9vdc one... I will power it properly, won't I ?

I do have a 12vdc pin in my power supply with no use...  

Ah ! Thanks for those mod tricks

PD - The front design is amazing too   Any audio clips, please?

[juansolo]

Thanks !!  

So, you are powering it with a 9vdc supply and This 9vdc goes into the Road Rage to get those 12vdc, aren't you?

So... If I use a 12vdc source, instead of a 9vdc one... I will power it properly, won't I ?

I do have a 12vdc pin in my power supply with no use...  

Ah ! Thanks for those mod tricks

PD - The front design is amazing too   Any audio clips, please?

It's powered with 12v, which goes to the road rage and to the heaters. Out of the road rage comes 23v which goes to the plates. Also a regulated 15v (actually might be 18v come to think of it, can't remember. It would make more sense though), which is going to the buffer.

Sadly I don't have any recording gear at all to do clips

Edit: Cleggy informs me that we did indeed go with a 15v reg in the road rage. The TL72 in the buffer can take 18v max so he went a little lower for some leeway.

[Jimihendrix1987]

Theres a buffer on the output and theres Madbean's Road Rage providing 15v to that, 23v to the plates and 12v to the heaters. It can take a variety of valves, but out of what we had, the NOS Brimar 12BH7 sounded best.

Ok. Let me see... You are using a 12vdc supply which goes into the Road Rage to provide 23v ( or 24?v)... With the Road Rage you are also getting a 15v regulated to supply the buffer, (i've just got a klon so I'm not going to need the buffer, in order i'm not going to use a regulator)

Which IC are you using in the Road Rage for that 12v-23v operation?

Ok I've redrawn the Schem, it is based on your Boob tube pedal !



I think it's allright ! But i've got a few question, which I hope you will be able to answer

1.What do you get providing the valve with those 2 different voltages, (appart for the more headroom)?
2.What's the main difference between the Original ValveCaster and your "modded" Valvecaster?
3.What is happening with r3 (100k) and the 3rd lug of the tone Pot?
4.Could I use a non electrolitic 1uF cap to replace c3? Will it improve the tone?
4.Which one do you like best? Original or this? Why?

I'm quite interested in this pedal ! I cannot hear it, but it's really cool !! I'm going to give it a try ! (I'm going to make this one and the original !)

Thanks Juansolo !

[nzCdog]

Awesome pedal, and cool ideas!  I've been tempted to looking at these, but I have only heard average demos on the net.  Do these low voltage tube pedals still get the nice valvey overtones and dynamics?

[juansolo]

I'll try and answer all of these

Which IC are you using in the Road Rage for that 12v-23v operation?

The MAX1044 can take 12v. Out of it comes 23.something volts.

Edit: Scratch that, it's actually what Cleggy* says below (as me). For some reason I had it in my head we'd stuck a MAX1044 in there.

*lol that you're still using my account on these sites! Set yourself up you lazy arse

1.What do you get providing the valve with those 2 different voltages, (appart for the more headroom)?

The heaters want 12v, you don't want to be giving them any more. The plates actually want much more voltage than the road rage provides as a lot of these tubes will struggle at 12v. If you fancy building your own charge pump then go for about 45v. 23v is just as much as the road rage can deliver.

2.What's the main difference between the Original ValveCaster and your "modded" Valvecaster?

Sonically, quite a bit. They really change based on which tube you stick in there. If I was to discribe how this sounds, it sounds like the dirty channel of a valve amp on my MJW. It doesn't go all the way into metal style chugging, but it really nails that AC/DC crunch (and a little more). The original 9v valve casters use different tubes and are darker and not as tight as this.

Moving the gain was just an attempt to make the pot less noisy. The original design adjusts the bias which does the SHO crackle thing. Moving it between the stages and setting a fixed gain is a more amp like way of doing it.

3.What is happening with r3 (100k) and the 3rd lug of the tone Pot?

The tone pot is really just a treble cut. Pin 3 is not connected. 2 goes via a cap to ground and 1 connects to the output of the circuit and vol pin 3 (output is vol pin 2).

The R3 and R2 resistors mentioned by Cleggy the power feed to the plates. The 23-45v feed goes via them to pin 1 and 6 of the tube socket.

4.Could I use a non electrolitic 1uF cap to replace c3? Will it improve the tone?

If you notice that massive sweet style thing, that's our 1uF (it was a mis-order from eons ago, we've been using them up when we can since). We've always used a film cap for that anyhow.

4.Which one do you like best? Original or this? Why?

It's a toss up between this and the Philcaster I made. That's using some NOS RFT tubes and in single tube mode that does one of the nicest boosts I've ever heard (and was the inspiration for re-doing this circuit), it double tube mode it's a bit mental to be fair. Is it better than this one? Different I'd say.

I do prefer both of the tweaked valve casters to the original though. FWIW the splittable twincaster has a few of the mods on it already if it makes things easier to understand. Here's the diagram I did to work from for that:

[juansolo]

Awesome pedal, and cool ideas!  I've been tempted to looking at these, but I have only heard average demos on the net.  Do these low voltage tube pedals still get the nice valvey overtones and dynamics?

Yep, can do. They're a great fun (and enormously addictive) pedals to make as there's just so much tweaking you can do with them.

[juansolo]

This is Cleggy posting for Juan.

The MAX1044S can only take 10V, a TC1044s, or a ICL7660S can take 12V.
I think this build has a TC1044S in the Road Rage.

Here's a schematic I've drawn up, it makes it easier to see where everything goes.

There's still a crackle when the gain pot is turned, but not as bad as the original valvecaster, it might need a resistor to ground after the gain pot.  

[Jimihendrix1987]

Perfect ! Thanks a lot !!! I'm ordering the components right now !

I'm going to build something like a Box of Rock, with the Valvecaster and the Boob Tube ! ... One for slightly overdrive and boost and the second one for something else

EDIT: I have been reading the Cleggy drawn schem, and it's not exactly what Juansolo posted before. There is a 100k (R3) which didn't mention and there is not c2 (47nF) which is supposed to be soldered between tube pin 1 and gain pot pin 3?

Which one is correct? I've drawn exactly the schem with juansolo instruccions also following the pictures (where are 6 caps !) in Cleggy Schem are 5 caps ! 

[juansolo]

You're right, I'm missing the 47n before the gain pot.
I'll fix it and upload again.

Fixed, just do a browser refresh.

[jimmybjj]

really cool build

[bigmufffuzzwizz]

This looks great. All the tube pedals you make look really cool and I'm sure they sound great! I've been wanting to make one for awhile now just not too sure where to start. I'm probably gonna go with either this layout you posted right now or the original matsumin valvecaster just to start with..