BK Butler Bluetube driver

[zosotone]

John, it's possible change the values of the tone caps (3 band EQ) to make the pedal more "Marshall preamp"?

Your second built it's an BB enclosure? Nice project!

[johnk]

yep. it's in a 1590BB.

to change the tone stack to a Marshall one, in the tone section, replace the 250p with a 470p, the 22K resistor to a 33K, and the 220n and 47n caps both to 22n's.
you might also have to change the pot values.
the pot values in a Marshall are:
Bass: C1M
Treble: B220k
Mid: B25k

[zosotone]

Nice, thank you very much bro! you are the master!

[Freppo]

Great work as usual.

Could you post the vero layout in a higher resolution?
I can't read it... :(

thanks!

/ Fredrik

[johnk]

[Freppo]

Thanks!

I built and tested it today. Sounds great!!
I tested it with a 9v powersupply, my 12v supply made a horrible screetching sound, most likely because it's a crappy unregulated supply I borred from my screwdriver.. :P

The only thing that sounds a bit strange is the Hi control. It does affect the highs as it should, but when turning up the highs the signal gets a bit weaker overall, which is kinda wierd. It's a small drop in volume, but enough to bother me. I've checked all connections and they seem ok. Any ideas?

Tried a few different tubes and ended up with a rubytube 12AT7 (seems to have the same amount of dirt, just a bit less compressed sounding).

Another great layout John! Thanks again
cheers / Fredrik

[johnk]

i'll have to give mine a listen tomorrow again to see if there's any volume loss with the treble cranked up, but I don't remember it doing that

[zosotone]

With the Marshall mod:
- there isn't 250p, it's the 330p maybe?
- the 22k from the 12AX7A 1 true?

[johnk]

I just tested both of my builds as well as my original blue tube one and all of them lose volume when you crank the treble.

[johnk]

my layout is according to the BK Butler schematic so yes, the 22K is correct.
a Marshall tonestack uses a 470p cap and two 22n's.

[Freppo]

johnk wrote

I just tested both of my builds as well as my original blue tube one and all of them lose volume when you crank the treble.

Ok, thanks! Then it's supposed to be that way. I was worried mine had an issue.
I will box mine soon, drilled the enclosure yesterday, just waiting for the paint to dry.. :)

cheers
/ Fredrik

[zosotone]

Marshall tonestack. Do these changes are correct? new values ​​in red...

[zosotone]

Can anyone help me to check the changes?

[johnk]

I socketed those on mine so I could experiment with them but that looks correct to me.

[zosotone]

[Freppo]

This is my build

I took the tube socket from an old 60's radio..
I really suck at the graphic part.. DIY punk style.
Gonna change the knobs for better looking ones.

Great sounding pedal!!
I run it at 9v and it sounds very good.
Just a bit more headroom/output with 12v.

Cheers
/Fredrik

[zosotone]

Sounds great! where goes the pin 9 of the socket? internal shield?

[Jon Rep]

JohnK,  I am interested in the Blue Tube 903 & Real Tube 901.    I have already built The Boob Tube V1.5 from this site and modified it to get a Bassier Tone & I also Built the Matsumin Valve Caster.  I just wanted your opinion of how the Blue Tube 903 compare to these?   And  also Have you built the Real Tube 901 or have an opinion on it?  As always Thanks and I really like your work and contributions.

[johnk]

I haven't built the others so I wouldn't know how they compare. the differences between a 901 and 903 are pretty slight but the 901 has more gain/distortion than the 903. I prefer the 903 and a lot of people use a 12AU7 in their 901's to reduce the distortion.

[Jon Rep]

These Tube pedal builds can be noisy.  When you mentioned  Earthing to a single point to reduce noise I decided to add more earth connections to  my other Tube pedal builds and I was surprised that it did make a significant difference.  Thanks for the Tip. Much Appreciated.