Tube boost + overdrive running off a 9 volt battery

[Ripthorn]

So I just stumbled upon this thread which is extensive to say the least.
To sum up this is what I would like to do:

I'd like to build a tube boost using this technique (after reading up on en 12AU7 6111 Valve Caster Summary PDF):
http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCasterWiring.gif
But using 12v (since most people seems to prefer it) and adding a 7812 and a 100uF filter cap on the dc jack to eliminate hiss.
Which components are preferred if I want a subtle and sweet overdrive sound?

I'm a bit new to all this, but I can follow a diagram...
Could someone please supply me with a BOM?
A revised wiring diagram (with the above mentioned additions) would be great as well...


Best,
Arlaharen

If you plan to use a 7812, you have to supply at least 14V, so you would likely need a 15V wall wart at the minimum.  I think that tube selectionm will play a more ciritical roole in the result of this circuit than supporting components.  I don't have a BOM or diagram, but perhaps someone can help you out with that.

[Arlaharen]

At page 69 you got a good layout!

You mean this http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180?
It seems that allt the images are gone in that post....

[Arlaharen]

If you plan to use a 7812, you have to supply at least 14V, so you would likely need a 15V wall wart at the minimum.  I think that tube selectionm will play a more ciritical roole in the result of this circuit than supporting components.  I don't have a BOM or diagram, but perhaps someone can help you out with that.

Ah, ok. Is there some other way to remove the hiss when using 12V?

[turkey101]

At page 69 you got a good layout!

You mean this http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180?
It seems that allt the images are gone in that post....

Hey, sorry guys - I don't know why the links had failed.  So, here is a re-post for Mr Arlaharen!  Thanks for your recommendation Renegadrian!


Hey guys, here's my effort.  First off, thanks to all those who have participated and provided great ideas on this thread!   I am indebted to Matsumin, Beavis and all those who have followed.

OK, so my "Valve'd" has a few mods as you will see by the schematic below:

* The "Clarity" switch. As suggested by Krinor - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg518458#msg518458
* I added a power on/off switch and run the heaters at 12.6VDC & the plates at 24VDC using a customised power supply on my pedal board that has all sorts of outputs.
* The Gain Pot bypass for clarity at lower gain suggested by Ripdivot - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg516969#msg516969
* Various filter cap and plate resistor mods to vary gain and frequency range

I hope this helps some other people.  I really enjoyed this project - especially the extra hardware for the enclosure.  I also think running the pedal at the higher voltages helps the structure of the sound, but this thing will still run nicely at 9VDC on both power inputs - versatility is what makes this circuit so special!  Extra thanks to Renegadrian, who seems to be keeping this whole thread together!   


Excuse my Beavis-style schematic . . . 



I went for the all polished chrome/stainless look and added a high intensity blue LED up the centre of the valve socket that lights up when the effect is on - mmmm, blue! 





An nice old Mullard 12AU7 for that extra creamy goodness!



Obligatory gut-shot



And finally, the vero I used:



Cheers,

turkey101

[Renegadrian]

At page 69 you got a good layout!

You mean this http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180?
It seems that allt the images are gone in that post....

There's a good layout by member w437776 - it seems easy to build!

[Arlaharen]

At page 69 you got a good layout!

You mean this http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180?
It seems that allt the images are gone in that post....

Hey, sorry guys - I don't know why the links had failed.  So, here is a re-post for Mr Arlaharen!  Thanks for your recommendation Renegadrian!


Hey guys, here's my effort.  First off, thanks to all those who have participated and provided great ideas on this thread!   I am indebted to Matsumin, Beavis and all those who have followed.

OK, so my "Valve'd" has a few mods as you will see by the schematic below:

* The "Clarity" switch. As suggested by Krinor - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg518458#msg518458
* I added a power on/off switch and run the heaters at 12.6VDC & the plates at 24VDC using a customised power supply on my pedal board that has all sorts of outputs.
* The Gain Pot bypass for clarity at lower gain suggested by Ripdivot - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg516969#msg516969
* Various filter cap and plate resistor mods to vary gain and frequency range

I hope this helps some other people.  I really enjoyed this project - especially the extra hardware for the enclosure.  I also think running the pedal at the higher voltages helps the structure of the sound, but this thing will still run nicely at 9VDC on both power inputs - versatility is what makes this circuit so special!  Extra thanks to Renegadrian, who seems to be keeping this whole thread together!  

Thanks!

So if I want stick to your layout but only use one 12V input and skip the breadboard, how would the diagram look then?
(sorry about the basic questions, I'm fairly new at this and need to be baby talked)

Best,
Arlaharen

[w437776]

can i run the plates at 170V dc?  this seems like a good idea: http://www.ledsales.com.au/kits/nixie_supply.pdf

[Renegadrian]

I never went that high, but yeah you can try for sure - also that PS has a trimmer to regulate the output voltage - I guess the plate resistors should be raised to 1W or something...but I'm no expert when talking high voltage (but yeah if we're talking AC/DC, the band I mean)

[frequencycentral]

can i run the plates at 170V dc?  this seems like a good idea: http://www.ledsales.com.au/kits/nixie_supply.pdf

I've used that SMPS:

http://www.diystompboxes.com/smfforum/index.php?topic=78302.0

http://www.diystompboxes.com/smfforum/index.php?topic=74088.100

No need for 1W plate resistors!

[Renegadrian]

uh ok Rick - good to know then!

[w437776]

so i can use this power supply without changing the valvecaster schematic?

[frequencycentral]

so i can use this power supply without changing the valvecaster schematic?

I would guess so, but keep the volume control down when you try it, as you may find the output volume insanely huge. I've got that SMPS built onto a small piece of perf for experimentation, if I get the chance I'll hook it up to a Valvecaster over the holidays and report back.

[dotfret]

I ran across this thread by accident a while back. then I found my registration for this site had lapsed a hundred years ago ...

Anyway, I have a couple of suggestions, based on mucking about with glass bottles for a long time. And all down to me being a cheapskate ...

Firstly, if a 12AU7 works, why not use a 6SN7? Very similar but octal base, and easy to find NOS versions cheaply. If you buy the Russki 6N8S versions on eBay, they are "cheap as chips". Look very impressive ...

Another valve that should work in the circuit is the ECC804 / 6GA8  which was designed for low noise - warning, different pin-out from the 12AU7 (pin-out like 6DJ8), 6.3V heaters only. You see them selling cheap, because nobody uses them in any modern design. They hit the market at the wrong time, when transistors were taking over, so they were never popular except in obsolete TV circuits.

A couple of other obscure types that might be useful -

5963 was for use in computers - sometimes they are great, sometimes they are noisy, they look like a possible alternative, and are usually cheap.

The Russian 6N6P is another possibility. Audiophiles  get wet in the underpants about them, but they are hard to find, and you will be offered the 6N6P-I or 6N6P-VI most often - these are pulse mode valves, and are sometimes noisy.

I have not tried any of these ideas. Frankly, I don't have time right now - but I don't see a lot of harm in giving people my ideas. What's the point in having obscure knowledge if you don't share it occasionally? Anyway, I am pretty sure a 6SN7 will do the job, no messing, and a 12SN7 will do it too! Might as well use up those old things and stop them cluttering up a couple of nations ...

[Renegadrian]

Welcome! 5963 - yeah I used one with good results!
thx for your suggestions...

[trad3mark]

i guess it should probably go here.

I'm working on a new design semi-based on this. Basically i've been looking at the transition/connection between triode and FET. I'd love to basically make 2 cascading fet/triode boosters running off the one 12AX7. The problem is, i can't seem to get levels of gain anywhere near the likes of simple fets like a j201 or a 2n7000 or a BC108. I'm trying to do this all (ambitiously) on 9 or 12V.

So, basically, what's the easiest way, on 9v, to get so much gain out of half a 12AX7 that it will produce overdrive like a FET would? I'm using this as a basic schematic by the way:
http://aikenamps.com/CommonCathode.htm

[camperus]

Aren, thx for pointing out those errors, so here is version 0.5!!! (should be final...)




Hey, post some pics of your version!!! I'll be glad to see them!!!

Sorry im a noob but... Where is the ground?

[Renegadrian]

ground is usually on one of the jacks. Try to tie all ground wires there. Or to ease the wiring (less wires going to one point) solder some of those "to ground" points on the second track (there are 3 holes unused), and then run the wire on the left to the jack.

[sporry]

Guys,

Some of the drawings (e.g. the one shown in the post from Renegadrian on February 19, 2008, 10:35:40 AM), show that capacitor C4 is located between the ground (same ground connection that the volume pot is connected to) and the middle lug of the Tone pot.
However, the schematics that go around show that C4 is located between the tone pot and C3 (and the Volume pot).
Why is there a difference and what effect does this have on the unit? does this perform teh exact same function as teh schematics indicate? (I don't have that great electronics skills). If so, why wire it up differently than the schematics, if it does the same job anyway?
If it doesn't do teh same job, why are the schematics not drawn to reflect teh actual connection? (that one seems really odd to me...)

Another point is, the Tone pot and gain pot appear to have two lugs connected to ground on teh schematics, yet the connection diagrams that indicate teh components again do not seem to follow this principle. What's going on with this?

I'm hoping to start building my unit today, so I look forward to a speedy response.

Cheers guys!
Kryn

[Renegadrian]

Welcome Kryn, glad you are going to build a Valvy!
I guess you meant this layout here --->LINK
Assuming this, and comparing it to the schem by Dano at the first page, let's explain how it works...
You see in Dano's that the signal leave C3 (it can be polaryzed or unpol.) to go to (pin 3 of) the volume. Just in between there is the tone cap and the pot controlling how much signal is going thru that cap to ground.
You also see Dano's PTP diagram here --->LINK He had C3 going to pin 3 of tone pot, but that way it worked counterclockwise, so using pin 1 fixed it. As you have surely read, it's verified by myself (my first one had the tone pot) and a lot of other people!

[sporry]

Hi, thx forthe quick reply!
Yes, I read it during lunch.
Now what I wonder is, should I use 9V or 12V when using the 12AU7's?
I can get a regulated 12V DC PSU, but not a 9V, in which case I wouldhave to cobble up a circuit to rgeulate that (I guess that would be easy if I just drop it to 9V with a voltage divider circuit and still use the PSU...)