help building the jon anderson 6au6 tubeboost pedal

[smitty]

Hello Everyone,

This is my first post here...   I just finished modding my tubescreamer ts-9 to ts-808 "brown mods" and replaced
the op amp to a ic socket, with a TI 4558p chip...   WoW!  outstanding much better brown tones...   I am a lap steel
player and these mods transformed this pedal into something I will use all the time on my pedal board.....   that being
said...  I am now fully addicted to making sonic "stuff"....    

I would really like to build a 6au6 pentode stomp box, and found jon andersons most excellent schematic....  but Im not
sure (being a newbie) how to turn the schematic into a layout, and then into a working reality....   I was wondering if anyone
could help me out....   I would like to try it on a breadboard first,  just not sure how to tie all the components together
on the bread board...

Also, it looks like this is using 36v?  and I was wondering if it could work off of a 9v battery....

here is the link to the schematic:

http://sites.google.com/site/jonandersonmn/schematic.jpg

thanks very much in advance for the help

Smitty

[frequencycentral]

Hi Smitty, welcome to the forum. Easiest way to breadboard with full size tubes IMO is to solder breadboard jumpers to a tube socket then just plug it in to the breadboard, like this:



You can get the 36v by using a voltage multiplier, simplest for a noob would be a MAX1044/ICL7660S based one such as this:

http://www.diystompboxes.com/smfforum/index.php?topic=74088.msg738236#msg738236

....which will give you more than 36v, but that's even better in this case.

You'll also need a 7806 voltage regulator to keep the heater at a stable 6v.

Yes this could work from a 9v battery, but will positively eat them up, better to use a wall wart.

[smitty]

Hi Smitty, welcome to the forum. Easiest way to breadboard with full size tubes IMO is to solder breadboard jumpers to a tube socket then just plug it in to the breadboard, like this:



You can get the 36v by using a voltage multiplier, simplest for a noob would be a MAX1044/ICL7660S based one such as this:

http://www.diystompboxes.com/smfforum/index.php?topic=74088.msg738236#msg738236

....which will give you more than 36v, but that's even better in this case.

You'll also need a 7806 voltage regulator to keep the heater at a stable 6v.

Yes this could work from a 9v battery, but will positively eat them up, better to use a wall wart.

Thanks for the reply,  I really appreciate it...     Another question for you in regards to the voltage multiplier, does that work from a 9volt battery?  and then
it multiplies the voltage from there?    Or  if I used a walwart would I skip the voltage multiplier and just use the voltage regulator?

thanks again

smitty

[frequencycentral]

Yep the voltage multipler works from 9v and multiplies from there.

The voltage regulator is to get a stable 6v for the tube heater.

You'll need both, regardless of your power source, battery or wallwart.

[iccaros]

From my experiences with the 6au6 in a pedal
I have built that with just 12v and it gives more gain then effects after can handle, and would cause my delay to distort in a bad way, I added an extra 1m pot to the output before the cap.

also I have found that on battery I get about 30 - 45 min of use, If you added two batteries to get 18volts, you would gain some of the headroom and have a decent time period, no matter what, you need the regulator for heaters as anything over 6.9 volts is out of specification. I like the 6au6a better in this setup, if you add a vaulecaster in front of this, it is nice..

[smitty]

From my experiences with the 6au6 in a pedal
I have built that with just 12v and it gives more gain then effects after can handle, and would cause my delay to distort in a bad way, I added an extra 1m pot to the output before the cap.

also I have found that on battery I get about 30 - 45 min of use, If you added two batteries to get 18volts, you would gain some of the headroom and have a decent time period, no matter what, you need the regulator for heaters as anything over 6.9 volts is out of specification. I like the 6au6a better in this setup, if you add a vaulecaster in front of this, it is nice..

Thanks very much for the reply...   I actually want to use this as an "organic" clean boost for my guitar amp, which is an old 50's danelectro with a 6au6 preamp section... into 2 6v6 push
pull...   Would you (or anybody) have any pics of a completed breadboard circuit of this particular circuit...   Im a noobie with little experience using a breadboard and would like to
breadboard the circuit first to play around with it....

thanks,

smitty

[smitty]

Yep the voltage multipler works from 9v and multiplies from there.

The voltage regulator is to get a stable 6v for the tube heater.

You'll need both, regardless of your power source, battery or wallwart.

Just a quick question for you....   If the heater requires 6v, and I use a 9v wall wart...  why would I need a voltage multiplier?   sorry for all the noob questions,
and really appreciate your input....

smitty

[iccaros]

Yep the voltage multipler works from 9v and multiplies from there.

The voltage regulator is to get a stable 6v for the tube heater.

You'll need both, regardless of your power source, battery or wallwart.

Just a quick question for you....   If the heater requires 6v, and I use a 9v wall wart...  why would I need a voltage multiplier?   sorry for all the noob questions,
and really appreciate your input....

smitty

the voltage multiplier is to get to the 39 volts listed in the schematic. The regulator is to reduce voltage to 6.3 volts (about), as running tube heaters at higher than 6.9 would cause damage to the tube. The tube its self is designed for hundreds of volts on the plates, so  increasing the voltage on the plates  gives more headroom.

I do not know what you mean by organic, and as for picture of a bread board you can look up skyhunter on the board, it is this design, but with submini version of the tube. But I do not know what looking at a picture of our breadboards get you, as I would not wire anything based off another breadboard as you do not know if it pre-trouble shooting or not.

[smitty]

Yep the voltage multipler works from 9v and multiplies from there.

The voltage regulator is to get a stable 6v for the tube heater.

You'll need both, regardless of your power source, battery or wallwart.

Just a quick question for you....   If the heater requires 6v, and I use a 9v wall wart...  why would I need a voltage multiplier?   sorry for all the noob questions,
and really appreciate your input....

smitty

the voltage multiplier is to get to the 39 volts listed in the schematic. The regulator is to reduce voltage to 6.3 volts (about), as running tube heaters at higher than 6.9 would cause damage to the tube. The tube its self is designed for hundreds of volts on the plates, so  increasing the voltage on the plates  gives more headroom.

I do not know what you mean by organic, and as for picture of a bread board you can look up skyhunter on the board, it is this design, but with submini version of the tube. But I do not know what looking at a picture of our breadboards get you, as I would not wire anything based off another breadboard as you do not know if it pre-trouble shooting or not.

ok,  I guess I am getting confused as I found another schematic for the "valvecaster" which uses a 12au7 based approach, and it runs off of 9v DC...  here is a link:
http://www.diystompboxes.com/smfforum/index.php?topic=63479.0

so Im still not sure as to why the voltage needs to be so high,   I believe this valvecaster does not use a voltage multiplier either?   Im wondering if I can use the single tube valvecaster
(if you read down the post DANO12 has a working schematic of a single tube version) but wire up a 6au6 pentode in its place?

as far as "organic" I just mean "warm" tube tone....  Im looking for more of a clean boost tube pedal as apposed to distortion, as I am a steel guitar player....,  thanks for the breadboard
tip...  I will just have to get one and figure out how to wire it up.....

thanks again,

smitty

[iccaros]

if you run this at 12volts and regulate to 6volts for the heaters, you will be happy then. No need to run at 38v or what ever that was.

see here

I have built this and get what your asking for

The thread is here http://www.diystompboxes.com/smfforum/index.php?topic=92201.0
I hope this helps

[smitty]

if you run this at 12volts and regulate to 6volts for the heaters, you will be happy then. No need to run at 38v or what ever that was.

see here

I have built this and get what your asking for

The thread is here http://www.diystompboxes.com/smfforum/index.php?topic=92201.0
I hope this helps

thank you very much!    Also looking at this schematic...  does this schematic show the voltage regulator in it, or is this something I need to add to this schematic?

thanks again,  you have been very helpful....   

[iccaros]

its does not, it also does not show the heater connection either. that is pins 3 and 4
see the datasheet
http://www.r-type.org/pdfs/6au6-1.pdf


more tube information
http://www.valvewizard.co.uk/