Bk Butler TD New vs. Vintage

[Vintagestomps]

Hi all,

So, I apologize for being redundant on this subject. My curiosity has got the better of me. So, I've owned a newer made BK Butler Tube Driver since their release. Prolly got one of the 1st units. I loved it, sure. But, I never stopped lusting after a vintage unit. Well, two days ago I received a vintage TD and so blown away. #1 that it works and #2 the feel of it sound wise. It has a GE 12AX7, sounds really sweet. In comparison I pugged both TDs' in. My '06 has this frequency that's pretty muddy and dark where as the vintage unit sounds transparent and not so muddy.

Doing some research I found a post here of a cat who went through the new TD's board and noticed one of the resistors was updated from a 2.2K, to a 22K in the tone section. (He told the "R" number but I don't recall it). The member speculated that perhaps it was designed that way to help achieve EJ's warm tone. All I found it was jus annoyingly dark that I could never get rid of.

Now, the reason for my post is, I need help locating the tone section of the new TDs board. So I may change the resistor. Maybe not to original specs of a 2.2K, but a middle ground perhaps. Find a medium to warm but not muddy. Of course, the units are only reacting to what ever amp and guitar its in between. I do tend for a warmer sound. But the way the new TD is designed is just too dark. And the vintage one, in all it's glory is brighter which allows me to be able to play with me amps eq for adjustments. Where as my newer TD there wasn't too much room.

Anyway. I look forward to some replies. Thanks in advance.

[Kipper4]

google the schematic and I think you'll find its R13 or R11 right after the second tube depending on which schemo you look at.

[tubegeek]

Doing some research I found a post here of a cat who went through the new TD's board and noticed one of the resistors was updated from a 2.2K, to a 22K in the tone section. (He told the "R" number but I don't recall it).

You've already answered your own question. If you found that post once, you can find it again, right?

[Vintagestomps]

Hi all,

Thanks for the replies. Ok so I found a decent schematic and more importantly a pic of the board with the "R" numbers shown. So supposedly "R14" is where the tone stacking is (for those who have the board pic). Not sure I wanna make my '06 TD sound exactly like my vintage one (but it's nice to know I can). Maybe a resistor a lil higher than the original 2.2K.

Again thanks to all that replied. Truly appreciate it.

[tubegeek]

Now throw up a link and you can get a backup set of eyes or ten to confirm.
Welcome a board!

[Vintagestomps]

@tubegeek

Here you are brother:

http://stompboxed.blogspot.com/2012/07/baja-tube-driver-bk-tube-driver-repro.html?m=1

Again, I just needed to see the board and "R" numbers laid out. Not trying to rebuild it (although that would be a good piece of knowledge when the day comes where my TDs' have big probs) for now just wanna change the '06 TDs overall dark sound.

All the best.

[Kipper4]

if your looking at the hand drawn schematic (bottom of the page) I suggest its R13
thats the start of the tone stack and the resistor in question
others will put me right if im wrong

[Vintagestomps]

@kipper4

Aw, right on brother!! Appreciate you looking out. Would have been a drag to change the wrong resistor. Thanks again!

[Vintagestomps]

Hi all,

So I got the board out of the chassis. Measured R14 and it is already 2.2K. And as per "kipper4"'s suggestion R13 measures 21.9K (22K basically). So I guess that's the one that makes it so dark according to "kipper4", says that's the beginning off the tone stack. Thing is, on the drawing of the TDs schematic, R13 is correct at 22K. And in the drawing the tech added the new models have a 22K at R14 rather then 2.2K, but my model has a 2.2K at R14 so that's vintage correct.

So, is it for sure R13 is the culprit? When compared to the vintage schematic, my new TD is has correct values in the "R" positions in question. So is there another reason my '06 is darker than my vintage unit?

Btw, I too run my '06 with the eq knobs at 0. They are way too harsh in either direction to my ear.

Any thoughts will be appreciated. I think instead of swapping out, I'll just install a 100K trim pot and attach it to the problem resistor. (Like I did with my own built si FF).

Thanks in advance. 

[tubegeek]

I think that R13, R14, and R15 will have some interaction to change the behavior of the tone stack.
Have you tried messing with the Tone Stack Calculator at www.duncanamps.com? That should let you mess around virtually. Another idea would be to use some resistors of various sizes and some clip leads and see how you like what you hear.

It does seem like your unit has the values you were hoping to swap to.

[Vintagestomps]

@tubegeek

Right on bro. No I haven't. I'll have to try that site.

Thanks again all.

[KazooMan]

Just another though for you to consider.  The values of the components in your vintage pedal may have drifted a bit over time and they were actually the usual +/- 5 - 10% when new.  You can build an "exact" replica with new components and it will probably sound different.

I did just that with a Fender spring reverb.  I own one of the originals that I purchased in the mid-sixties.  Just for fun and the learning experience, I built a clone. Supposedly the "identical" transformers, choke, tank, tubes, and components.  The two units are both nice, but they sure do sound different.  The vintage reverb has a much nicer sound, probably because that is what I grew up with and am used to hearing.  The clone has a harsher sound to my ears, but it is a sound that some might actually prefer.  The difference remains the case even if I switch tanks and/or tubes between the units. 

I have built the "Baja" Tube Driver clone you referred to and it is great, but I don't sound like Eric Johnson when playing through it   In the case of a tube device, the exact plate and bias voltages are going to make a big difference in the output.  I can't recall from the thread whether or not you have explored this.  This is akin to the mystique of leaky germanium transistors.  They all perform differently in spite of having identical markings on the cans.

[Vintagestomps]

@KazooMan

Thanks for your input. Indeed the vintage TD could have drifted to a perfect tone. Maybe in another 30 yrs the new one will sound close. Lol Im a lil disappointed that it wasn't an obvious answer. Regret taking out the board, the wires to the output jack (black one) came lose. Seems BK (or whom ever worked on it last) knotted the blk wire around the red so there wasn't enough slack. Ez enough fix but still. Lol

Thanks again all. Truly appreciate the help.