Tube boost + overdrive running off a 9 volt battery

[aka_basse]

Wow thanks alot guys!!

Jimmy -h - Great answers, made everything much clearer

frequencycentral - Wonderful list of tweaks, this is going to save me lots of time (not having to read through the thread all the time) and many others will probably find it useful

Renegadrian - Great layout, will probably follow that one. Can you get the sound of the "no tone" version with the "tone" version? What difference does it make to leave tone out? If Im going to use with both singlecoil and humbucker guitars wouldnt it be smart to leave it in there?

And if I understood correctly the effect will kick in instanly when you stomp it unlike, say, my amp which takes 10 sec before sound?

Thats all the questions I had for now (likely many to come)
once again, thank you all very much!!

edit: also, what kind of caps and resistors should I use?

[Renegadrian]

Renegadrian - Great layout, will probably follow that one. Can you get the sound of the "no tone" version with the "tone" version? What difference does it make to leave tone out? If Im going to use with both singlecoil and humbucker guitars wouldnt it be smart to leave it in there?
Well, the valvy is not so bright, so I had the tone always on 10 - else it will cut off all the highs and just won't cut thru...
Basically you have 2 ways
1. build it with the tone pot - it's very easy to get it out of the circuit if you'll find it useless as it was for me
2. Just go for the toneless version and get all the tone the valve can give...
I have several guitars, both SC and HB equipped, and no, I don't think the tone control is a must...
I use it with my bass too...

And if I understood correctly the effect will kick in instanly when you stomp it unlike, say, my amp which takes 10 sec before sound?
yes the tube will be always powered, as you can tell by the light of the tube itself

what kind of caps and resistors should I use?
standard components are used in this simple circuit.

Oh, before I forget...It was written several times that in order to avoid any hiss/noise, you need a good regulated wall wart, or use a 7812 voltage regulator and a filter cap on the DC jack. That is a must in my valvies...

[Darkness, Darkness]

Renegadrian - Great layout, will probably follow that one. Can you get the sound of the "no tone" version with the "tone" version? What difference does it make to leave tone out? If Im going to use with both singlecoil and humbucker guitars wouldnt it be smart to leave it in there?
Well, the valvy is not so bright, so I had the tone always on 10 - else it will cut off all the highs and just won't cut thru...
Basically you have 2 ways
1. build it with the tone pot - it's very easy to get it out of the circuit if you'll find it useless as it was for me
2. Just go for the toneless version and get all the tone the valve can give...
I have several guitars, both SC and HB equipped, and no, I don't think the tone control is a must...
I use it with my bass too...

There is also the possibility to use a pot with integrated turn-on-switch. I've got one in my emery sound amp, great feature 

[Renegadrian]

Well, almost everything is possible, but I believe it would be just too much...I think you won't regret the absence of the tone pot...

[JOHNO]

Well ive been messing around with this circuit today and while its supposed to run at 9 or 12 volts and it sounded ok at those voltages I just thought it was a waste. So I whipped up dano's voltage regulator using the LM317T and used a 5k trim pot because thats all i had on hand. Hooked it up to my bench top power supply and cranked it up to 20vdc.
Set the heaters to about 9v just to get the tube cooking a bit and it sounds pretty good. Im using a 12at7 tube by the way. I think it still needs some tweaking on the input caps and tone stack. The LM317T does need a heat sink so I just made one out of a piece of aluminium i had lying around. Anyway just thought you guys might be interested
Cheers JOHNO

[aka_basse]

hello again (and thanks for answers again!)

I've decided to keep the tone control. I'll put 3 switches in, was planning on using 1st one to reduce the gain to a clean boost; 2nd one for tone control on/off; 3d one for some other interesting tweak.

Any good tone mods to add to the last switch?

[cheeb]

Hey Johno, what voltage regulator do you mean? I'd like to supply mine with more than 12 volts to see what the outcome is. It would be great to have a power supply for the VC that has like a rotary switch for voltage selection.

[JOHNO]

Cheeb, check page five of this thread. Theres is a schemo there that dano came up with that has the voltage regulator in it. I that schemo dano uses a 6111 tube. Just apply the regulator section to the schemo on page one.
I have a question for dano, with the LM317T the spec sheet says that the tab is conected to the out pin of the regulator so I would think that means I need to keep the tab isolated from ground? Is that correct.

[Jimmy-H]

hello again (and thanks for answers again!)

I've decided to keep the tone control. I'll put 3 switches in, was planning on using 1st one to reduce the gain to a clean boost; 2nd one for tone control on/off; 3d one for some other interesting tweak.

Any good tone mods to add to the last switch?

What you could do, is to make a input cap selector.
With a rotary switch, just like I did with my Pepper Shredder.
So you can select the amount of bass That comes in.
For the smallest cap you have to use a good ceramic or  Silver Mica .
I used a 680pF.
just look here :  http://www.diystompboxes.com/smfforum/index.php?topic=63479.500

[frequencycentral]

....with the LM317T the spec sheet says that the tab is conected to the out pin of the regulator so I would think that means I need to keep the tab isolated from ground? Is that correct.

That is correct, isolate the tab.

[aka_basse]

What you could do, is to make a input cap selector.
With a rotary switch, just like I did with my Pepper Shredder.
So you can select the amount of bass That comes in.
For the smallest cap you have to use a good ceramic or  Silver Mica .
I used a 680pF.
just look here :  http://www.diystompboxes.com/smfforum/index.php?topic=63479.500

Thanks, sounds nice!
Yeah, all I got ordered is my 3 two way switches, sounds good to dedicate the last one to this. If you'd have to choose one of the caps (other than standard) which one would you make switchable? (which one is the most useful you think?)

[rm -rp ./Matt*]

This is a nice thread, just about to start my valvecaster build, it seems that voltage regulation is a big issue.

Should I build a voltage regulation box (wall wart 60 or 200 perhaps?) and should I set to voltage to 12.6v?

[Jimmy-H]

Thanks, sounds nice!
Yeah, all I got ordered is my 3 two way switches, sounds good to dedicate the last one to this. If you'd have to choose one of the caps (other than standard) which one would you make switchable? (which one is the most useful you think?)

I did it with the input-cap.
For the valveCaster it's C1.

[Jimmy-H]

This is a nice thread, just about to start my valvecaster build, it seems that voltage regulation is a big issue.

Should I build a voltage regulation box (wall wart 60 or 200 perhaps?) and should I set to voltage to 12.6v?

The DC- wall wart should be at least 500 mA.
You could use a LM7812 with a diode (1n4148) on the centre pin (cathode to ground), this sets you up for about 12.6 volt.
And solder it on the input jack for the power supply, together with the 100 uF cap.

[rm -rp ./Matt*]

This is a nice thread, just about to start my valvecaster build, it seems that voltage regulation is a big issue.

Should I build a voltage regulation box (wall wart 60 or 200 perhaps?) and should I set to voltage to 12.6v?

The wall wart should be at least 500 mA.
You could use a LM7812 with a diode (1n4148) on the centre pin (cathode to ground), this sets you up for about 12.6 volt.
And solder it on the input jack for the power supply, together with the 100 uF cap.

Thanks Jimmy, by the time my tubes come in the mail I should properly know what your talking about and add it to the layout design My brain is working overtime learning all this stuff

[Jered]

Well ive been messing around with this circuit today and while its supposed to run at 9 or 12 volts and it sounded ok at those voltages I just thought it was a waste. So I whipped up dano's voltage regulator using the LM317T and used a 5k trim pot because thats all i had on hand. Hooked it up to my bench top power supply and cranked it up to 20vdc.
Set the heaters to about 9v just to get the tube cooking a bit and it sounds pretty good. Im using a 12at7 tube by the way. I think it still needs some tweaking on the input caps and tone stack. The LM317T does need a heat sink so I just made one out of a piece of aluminium i had lying around. Anyway just thought you guys might be interested
Cheers JOHNO

  Hi JOHNO, you want your heaters at a minimum of 12.2 volts, 12.6 is optimum for 12A_7 tubes. Better sound and longer tube life.

[Jered]

Hi everybody,

Has anyone tried some 6112 tubes ? I can't get any sound of it  Maybe the 6112 does not work at all with low voltage ? After all tubes are designed for high voltage... 

- I've build a Voltage regulator for the heater -> OK :  6,3v, the tube lights up

- At beginning I was trying to replace the JFET in the first stage of a working distorsion breadboard project just to test, and as is what not working I build on another breadboard the first stage of the valvecaster without more success I must say. Only difference : I run it at 24V (so I replaced the 220K  by a 1M pot to be able to set the bias...)

I've check, double check, and check again pins layout but it is good. (Even tried to invert anode/cathod just to be sure...) I don't get any sound and when trying to bias the tube at half supply voltage, there is almost no drop voltage on the bias pot (24-> 22V with a 1Meg pot set at full), meaning there is almost no current flow through the tube I would say 

What's you opinion ? Should I forget using these tubes ?

Thanks

Hi Darkness,

On page three there was this reply from Jered:

Dano, I forgot to add, I tried 6112 and 6021 tubes and the sounded horrible. That's all.
  Jered

So there most be comming some sound out of your tube, even when it sounds like sh*T !!!
I think with 24 volts this tube will sound great.
There has to be something wrong with your build.
Keep in mind that jered only used 9 volts!

I hope that you will find what is wrong! 

  hehehe...that was with the sub minis directly replacing the 12AU7's at 9 volts.  With a few tweaks and at higher voltages the sub minis sound like little tube amps. Everything from low/mid gain crunchy to high gain endless sustain. I'm in the middle of doing a small write up right now and schems for circuits using 6021's and 5784 pentodes. I was hoping to have the write up done by now but work has been hectic so time has been an issue. Hopefully I'll have it done within a week or so.

[Renegadrian]

I'm in for the high gain circuits...Eager to see your work!!! 

[JOHNO]

> you want you heaters at a minimum of 12.2v,12.6 is optimum for 12A_7 tubes.

Thanks jered, I thought we were shooting for 6.3v. Is the 6.3 for the 6111 tube is it? I'll crank up the voltage on the heaters a bit more ,Thank you . JOHNO

[aka_basse]

Thanks, sounds nice!
Yeah, all I got ordered is my 3 two way switches, sounds good to dedicate the last one to this. If you'd have to choose one of the caps (other than standard) which one would you make switchable? (which one is the most useful you think?)

I did it with the input-cap.
For the valveCaster it's C1.

Oh sorry, asked for the wrong thing heh, what I meant to ask was
which value of C1 other than standard 47nF would you choose if you only could choose between two values (a two way switch)