Tube boost + overdrive running off a 9 volt battery

[rugeb]

Rotary switch for input tone control:

Hey...
good one however i thought that the 68k resistor that the signal of a passive instrument faces drops the volume right?
Won't this lead to less gain?
I mean the ''stock'' circuit doesn't have that resistor.

It's not verified yet, look only rotary switch circuit with capacitors.

[Renegadrian]

* Yeah 9V will work but I noticed that making it work at the right voltage gives you a better sound, I think I like 12V (I use it on all pedals now) and you can get some 12V adapter for very cheap - I got one 1A and one 3A and they do the work!

* Isak, the kind of capacitors you are going to use is not that critical, as in a lot of pedals anyway (IMPO). I like ceramics (that a lot of people hate) or WIMAs (the red ones)

* I don't know if both a 68k resistor and (switchable) cap(s) cut too much sound at the input - actually I'd leave out one of those components.

[rugeb]

Many pedals work better at 12V, but others (fuzz type) require less than 9v (battery low).
You're right that the tube overdrive 12V would be ok, but for a beginners is easy at 9v (the same volts for all pedals).

[danamoose]

Don't get JJ 12au7 tubes for a 12v valvecaster, they don't work very well at low voltages.

thank you for pointing this out, what do you suggest?

I tried three different 12au7 tubes in mine before it sounded right:

1: JJs sounded terrible crunchy and harsh
2: Electro Harmonix sounded ehh better but not what I wanted
3: An older RCA 12au7a labeled lowrey organs...sounds amazing much smoother break up.

I run mine at 9v and it works fine. At 12v you do get more boost and more headroom. Pedal is just what I am looking for at 9v though I dont need any more headroom out of it and you get plenty of boost at 9v.
Hope this helps!
Dana

[juansolo]

Don't get JJ 12au7 tubes for a 12v valvecaster, they don't work very well at low voltages.

thank you for pointing this out, what do you suggest?

I tried three different 12au7 tubes in mine before it sounded right:

1: JJs sounded terrible crunchy and harsh
2: Electro Harmonix sounded ehh better but not what I wanted
3: An older RCA 12au7a labeled lowrey organs...sounds amazing much smoother break up.

I run mine at 9v and it works fine. At 12v you do get more boost and more headroom. Pedal is just what I am looking for at 9v though I dont need any more headroom out of it and you get plenty of boost at 9v.
Hope this helps!
Dana

Pretty much matches our thoughts. The RCA cleartops are about the best compromise of tone vs current draw that we've found. Best sounding of all that we've used was a Brimar 12BH7, but pulls twice the current and is much bigger.

[Isak]

* Isak, the kind of capacitors you are going to use is not that critical, as in a lot of pedals anyway (IMPO). I like ceramics (that a lot of people hate) or WIMAs (the red ones)

i ordered wima's polypropylene ones, thanks 

1: JJs sounded terrible crunchy and harsh
2: Electro Harmonix sounded ehh better but not what I wanted
3: An older RCA 12au7a labeled lowrey organs...sounds amazing much smoother break up.

Pretty much matches our thoughts. The RCA cleartops are about the best compromise of tone vs current draw that we've found. Best sounding of all that we've used was a Brimar 12BH7, but pulls twice the current and is much bigger.

thank you guys.
i actually bought 3 from ebay.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260951669480&ssPageName=ADME:L:OC:US:1123#ht_500wt_1180
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=230751585117&ssPageName=ADME:L:OC:US:1123#ht_708wt_1396
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290664027678&ssPageName=ADME:L:OC:US:1123#ht_1127wt_1163
i will try all 3 of them to see what i like the most.

i have a professional question.. (maybe its to late to ask cause i bought all the stuff i need to assemble this amazing project  )
can i use this as a sound warmer?
i mean..
not to extremely overdrive the sound, only a "bit", to give the sound fatness (know what i mean?) a bit more crispy and warm sound.
just a reminder, its going to be for a synth, not guitar.

thanks in advance for your answers. 

cheers,
Isak E.

[Renegadrian]

Yes! I used it a lot with my bass to fatten the sound, it does add a lot of warmth without going dirt (obviously not at full tilt) boosting all frequencies in a transparent yet "tubier" way...

[danamoose]

can i use this as a sound warmer?
i mean..
not to extremely overdrive the sound, only a "bit", to give the sound fatness (know what i mean?) a bit more crispy and warm sound.

Yes this is exactly what I get when I turn the gain on the pedal all the way down. It adds as much volume as you want with just a touch of dirty.
-Dana

[Isak]

thanks guys, i'm so excited   

another question if i may please...
i ask you cause your guys all ready into pedal boxes and so..
where can i get nice big aluminium enclosure for this project?
i need something like this http://www.ebay.com/itm/Tube-Amp-Chassis-DIY-12-8x7-1x2-3-Aluminum-Project-Enclosure-Stereo-Amp-Preamp-/250932265782?pt=Vintage_Electronics_R2&hash=item3a6cba8336#ht_739wt_1396
but not this crazy cost 

cheers,
Isak E.

[tasos]

You could make one?

[rugeb]

thanks guys, i'm so excited  

another question if i may please...
i ask you cause your guys all ready into pedal boxes and so..
where can i get nice big aluminium enclosure for this project?
i need something like this http://www.ebay.com/itm/Tube-Amp-Chassis-DIY-12-8x7-1x2-3-Aluminum-Project-Enclosure-Stereo-Amp-Preamp-/250932265782?pt=Vintage_Electronics_R2&hash=item3a6cba8336#ht_739wt_1396
but not this crazy cost  

cheers,
Isak E.

 
=========================  
For this project eBay search: 1590BB
=========================

[tasos]

Or tayda....
ain't that bad for about 9bucks including shipping

[chris73]

Hi everyone,

im new here and also in DIY but i managed to make some pedals by carrefuly reading all your advice here.

Also finished the ValveMaster which is amazing but even if i tried to bias it a bit differently i didnt manage to take out of it a totaly clean sound.
There is always a bit of dirt even with all the gain down.

Is there any way to remove all "dirt" from that great pedal?

(congrats for your forum again)
Chris

[Isak]

You could make one? 

i wish i had time for it. 

For this project eBay search: 1590BB

thanks but its too small i'm afraid.

[JRM]

A 1590BB has 110x84x34 it will be more than enough if you mill a hole for the valve. Even if you want to put the valve inside the enclosure it will fit if you place it horizontaly (you need 24mm and have 27.75).

[rugeb]

My project with 1590BB:

[Isak]

thank you for your good advice's.
guys i'll be making few effects in one box, like a multi-effect for synth.

this is the knobs i'll be using... (the out base is 4.5cm)




so the 1590BB wont do, sorry.
thanks guys.

[rugeb]

 
  ha, ha, ha....., of course! 

[candletears7]

Thanks to all for the extensive work on this great little circuit!

Yesterday I breadboarded the stock Valvecaster from Dano Beavis' schematic, and it sounds pretty damn good.

If you have a minute, read my progress in the search for the ultimate low gainer.
Previously I was using a Paul C. Tim for my low gain needs, but I run a 50w Plexi set to absolute clean, but loud. Zero breakup from the amp, so I felt that the Tim, while brilliant when combined with a bit of amp dirt, was not the pedal for me. So I got a vintage Marshall Bluesbreaker pedal. Again, great pedal particularly with mid scooped amps like a Fender Twin, but the Plexi has it's share of mids in its' natural tone, and the Bluesbreaker pedal/Plexi amp combo is a little too boxy in the mids for me.

I ran the Valvecaster on the breadboard through my Plexi and it's very good. I was lucky enough to receive 4 vintage 1950's 12AU7's out of an old Baldwin organ, courtesy of one of the wonderful BYOC forum members. However, as noted, being that the circuit is optimised for single coils, with my humbucking guitars there was just WAY too much bass, bordering into soft farty fuzz territory in the low end. Not good. I wound all the bass out of the amp, and got a great rocking Malcom Young sound.

I have been comparing the JuanSolo/Cleggy Boobtube schematic against Rick Holt's Valvemaster schematic, and I believe Rick's mods could be quite an improvement on the intial Matsumin design.
Having the gain pot after the first Valve stage (here in Australia we call 'tubes' "Valves") seems to make sense to me in that it allows the circuit to ramp up it's total gain level before bringing it down, as opposed to bleeding signal to ground from the get go.

Today I will make some modifications to the Valvecaster circuit on the breadboard, and aim to do the following:

1) Work out if dropping the input cap OR the coupling cap (both 47n in the initial schemo) to a lower value is better for removing unwanted low end frequencies. I'm imagining that I'll be putting that component on a switch to work for SC's/HB's as the need arises. The JuanSolo/Cleggy circuit uses a 10n for HB guitars, so I'll try that.

2) I want to hit the circuit with various voltages. Right now it's pulling 9v straight out of a 1-Spot. I use a Cioks AC10 for my main board, and I believe I have a 9v, 12v and 18v tap free on the powersupply.

Before I get into this, I see on the JuanSolo/Cleggy schematic that there is 12v going to Pin 5 of the valve, while 23v goes to Pins 1 and 6 of the valve. I have read the thread pretty extensively, so may have missed the answer if it already exists, but what are the sonic benfits of sending different voltages to different Pins of the valve? (I have done a lot of DIY pedals with transistors, FETS, opamps etc..., this is my first valve circuit). Question - Can I just try different voltages to the whole circuit, eg: 9v, 12v, 15v, 18v, 24v? Or can only one part of the valve only be fed with 9v, while other parts of the valve can take higher voltages?

I have a great hammertone Pedalenclosures enclosure to use for this project. I plan to have the valve up back in some kind of protective rail, and to rock the sh*t out of this thing. If it works well, then I hope this does my low to medium gain tones for me. My medium to high gainer is a Kingsley Minstrel, and man that pedal is off the hook. So, another valve pedal to pair with it seems like the go.

Thanks for reading, any answers to my question would be great, and I will post pics once I'm done.
Cheers!

[Renegadrian]

2) I want to hit the circuit with various voltages. Right now it's pulling 9v straight out of a 1-Spot. I use a Cioks AC10 for my main board, and I believe I have a 9v, 12v and 18v tap free on the powersupply.
Before I get into this, I see on the JuanSolo/Cleggy schematic that there is 12v going to Pin 5 of the valve, while 23v goes to Pins 1 and 6 of the valve. I have read the thread pretty extensively, so may have missed the answer if it already exists, but what are the sonic benfits of sending different voltages to different Pins of the valve? (I have done a lot of DIY pedals with transistors, FETS, opamps etc..., this is my first valve circuit). Question - Can I just try different voltages to the whole circuit, eg: 9v, 12v, 15v, 18v, 24v? Or can only one part of the valve only be fed with 9v, while other parts of the valve can take higher voltages?

you replied to your own question man! The heaters (pins 4-5) must be fed to 9 or better 12v. that's mandatory, you dont want to blow a tube!!! The other parts would benefit of more voltage! tubes were usually intended to run on high voltage, and you can read a lot of their curves thru their datasheets - low voltage experiments are quite unknown (we can say we are the piooniers of that...) so we can just argue the behaviour at low voltage...the main benefits of higher voltage at the anodes
is that you feed more "air" - also some 12ax7 can react better.