BK Butler Bluetube driver

[Jon Rep]

I decided to build the Bk Butler Tube Driver but I used Harald Sabro Design  12 Volt AC  on this link.

http://www.sabrotone.com/?p=3055

I kept the Tube Heating Part Connection 4 & 5 on the Tube seperate and used just 9V DC here.  I learnt the importance of the 10 Ohm resistor on this circuit to reduce noise as I think Javi  suggested in another post on this site.  Thanks

I have yet to get a decent 12 Volt AC power supply for this pedal.  I tested 6V AC and it was flabby But at 10 Volt AC I was amazed at the Sound. This is a worthwhile Tube Pedal Build.  Thanks for the Post John Kallas & Harold Sabro for all the work you do.  Much Appreciated.

[Jon Rep]

This Afternoon I also decided to test a 10 Ohm resistor on the 12 Volt AC  power input  and I believe this also has reduced any noise from the AC Source.  Sounds good on my 10 Volt AC source.   Not so Great on my 9V  & 6V AC Source.  Might be dependent on quality  of the  Adaptor and of course Voltage.   I believe will be best as reccommended on a Quality 12 Volt AC Source.  Thanks.

[johnk]

i'm glad to hear that powering yours with AC and using that 10 ohm resisotr and is working for you.
there are amps and mods to amps that power their preamp tube filaments with 12V DC instead of AC to minimize hum so that's what I ended up doung. mine are completely hum free and actually quieter than my original blue tube pedals. plus I have the luxury of powering my tube driver with a standard 9V or 12V dc adapter instead of having to use a dedicated power supply.

[Jon Rep]

JohnK,  I may eventually like yourself use your design with the ICL7660SCPA.  I wanted to first try Harald's design because I read BK Butler say other Clones like the Chandler don't sound the same because they use a Wall Wart. To me his Pedal does sound Richer and Fuller.   I therefore believe How you supply the 12V AC to this pedal will make it sound great or ordinary and decided to experiment which is ongoing.  I really like Tube Pedals and also Tube Amps.  Thanks for introducing me to this pedal on this site.

[Jon Rep]

Wonder if the Original BK Butler Pedal has additional AC Hum Filter Circuitry similar to described on the following Link?

http://freecircuitdiagram.com/2008/08/08/hum-filter-an-ultimate-weapon-to-remove-ac-line-noise/

[johnk]

my original tube driver doesn't have it.

[Jon Rep]

Ok Thanks JohnK . So I Guess the Original you have still as you mentioned  put out some AC hum.   I measured the 10 AC volt adaptor (For Harald Sabro AC Design)I had that makes the pedal sound good and it actually  is putting out  12 AC volts.  I got hold of a 12 Volt AC Adaptor and it actually is putting  out 14 Volt AC  and did not sound as good.  I am still getting  slight AC Hum through the speakers which to me is also Annoying.

[johnk]

yep, that's why I went with a DC supply. mine sounds great with either a 9VDC or 12VDC supply.

[zosotone]

This baby sounds very good with 9VDC! It's possible supply the pin 4 of the tube only with more voltage? for example, with the 33VDC charge pump from the Boob Tube V1.5...

[zosotone]

Finished!

[raydee]

Hello

I wonder about that 100R in your layout johnk?

In the schematic I found, that resistor is 100K.
Is the schematic wrong, or am I missing something here?

[velouriafx]

Is it not necessary to use a heatsink for the valves? Why some brands use, in case it is not necessary?

[johnk]

no heatsink necessary.

[kragg]

Hello,
Thank you JohnK for the layout.
One little question about the power supply : below the veroboard it is written "iCL7660SCPA", while on the veroboard it is labelled "LT1054", so which kind of chip should we use ?

[HamishR]

Earlier in the thread John says to use the LT1054 because it can take higher voltage than the ICL7660SCPA.

[kragg]

Thank you, Hamish.

[kragg]

I am planning to build this in the next weeks, and by looking at the schematic, two things seems strange to me :
1- Isn't the 2.2µF electrolytic capacitor at the bootom right in the wrong orientation ? Unless i'm wrong, the "-" should go to ground, isn't it ?
2- Is the cut on the top row mandatory (there are 3 cuts one on top of each other at the center top, and the highest cut doesn't seem needed, as far as i see) ?

[BetterOffShred]

Hey man - if you follow the 2.2uf caps path .. it goes back to (-) power so the + side goes to ground as it's higher potential.  

As for the cut, I see no reason to include it unless you wanted some spare columns to add other circuitry or a mounting stud etc.  

[kragg]

Thank you, Lovecraft fan !

[kragg]

Hello,
I have built it, and it *somewhat* works :
- The valve is getting lit and i hear distorsion;
- I can hear the effect of the gain, level, low, mid and treble knobs;
So, so far so good... :)

But I still have a couple issues :
- I get a LOT of hum (nearly as loud as the signal !). I guess something is wrong with the grounding, but i have triple-checked and so far i can't figure out what it is...
- The LEDs do not light as expected : the POWER led is not lit as soon as I plug the pedal, and the STATUS led doesn't light up when i engage the effect. Instead, they blink according to the signal (like when I use diodes in the audio path of a fuzz pedal !);
- The treble knob behaves quite strangely. It seems it affects more the level and bass amount than the treble amount (while "low" and "mid" pots behave as expected). It's a bit like a state variable filter : when you turn it on one side, it feels like it's cutting the bass more than boosting the mids. I have read a bit above that the treble pot was quite unusual, but is this to be expected ?

I will troubleshoot my pedal further tonight, but since i have already checked it three times this morning, I would be open to suggestions :)
I guess that, as the wiring is a bit unusual (3PDT wiring, 2 leds, tube socket, daughter board, etc), I may have made a mistake somewhere, but i can't figure out where