Tubeman I tubes and pots

[tom_dunham]

Hi,

I was wondering if anybody had schematic for this pedal. If not, could some kind soul that has one possibly open it up and check the pot values for the mid, bass, treble and gain?

Why do I need this?

I replaced them using the "physical layout method", and my cat attacked them, thus scrambling my foolproof method... Doooh!!

I know this is a pain but thanks in advance.

BTW
changing the tubes if you decide to open it up is a good idea...

GT HG12AX7 sounds very nice and best overall balance, very lively, a little too early compression on Blues (1st place)
Tung-Sol reissue = tinny on HG and Blues but excellent for funk and country
60's Old RCA = good overall, a little dark for strats but just right HB
80's Sovtek W = good, not overly complex
80's Sovtek WGA = very good overall but a tad rough on top
80's Sovtek WGB = good
60's Amperex = good overall (2nd place)
Generic Sovtek = good

[Trout]

Originally posted by tom_dunham
Hi,

I was wondering if anybody had schematic for this pedal. If not, could some kind soul that has one possibly open it up and check the pot values for the mid, bass, treble and gain?

Why do I need this?

I replaced them using the "physical layout method", and my cat attacked them, thus scrambling my foolproof method... Doooh!!

I know this is a pain but thanks in advance.

BTW
changing the tubes if you decide to open it up is a good idea...

GT HG12AX7 sounds very nice and best overall balance, very lively, a little too early compression on Blues (1st place)
Tung-Sol reissue = tinny on HG and Blues but excellent for funk and country
60's Old RCA = good overall, a little dark for strats but just right HB
80's Sovtek W = good, not overly complex
80's Sovtek WGA = very good overall but a tad rough on top
80's Sovtek WGB = good
60's Amperex = good overall (2nd place)
Generic Sovtek = good

My brother has one over at his Studio, I have been trying to pry it out of his hands for a couple years, If you do by chance locate a schematic, Please forward me a copy. That may have been the best unit ever produced!

Trout

BTW, he still has the re-labeled Hughes Kettner tube in his. It was my understanding that the original model ( the one he has) was a very limited production unit and less that 1000 where made.

[tom_dunham]

Hi Trout,

My original tube was totally generic and I think it is a Sovtek 12AX7 b/c I have other Sovteks without markings that look very close: it think the Tubeman tube was glossier on some plates than the Sovtek. My guess is that Sovtek made the tube and probably custom for the application. I still have it - I'll take some pictures and post later.

I read your other post, the Tubeman I is a very good product and in my discussions H&K tech support (they had no schematic either), they said the Tubeman I was engineered around the '59 Bassman where as the new ones are more "Marshally" (? '59 Bassman again... but different) and that, like you, many customers prefer the old Tubeman to the new ones.

When I looked at the Tubeman II schematic, I noted the ratio of the pots, in terms of highest to lowest values, is the same as what I have so I believe I made a good guess and it does sound "right".

What I really want to do is break out the selector switch into stomp buttons with separate gains but I think I may be dreaming based on how picky the chasis grounding is. You can't take the unit apart and switch tubes - you have to put it all the way back together for it to run. I actually returned my first Tubeman under warranty b/c the pots were no good and then years later, I ordered replacement pots and a power supply hoping they had found a new supplier, which they had, and things have been much better in terms of scratchy pots. Actually, H&K gave me the pots for free when I bought the power supply.

I will definately forward a schematic if I get one!

[Trout]

After 2 years of twisting my brothers arm, It looks like I will be getting his in a couple weeks. He has decided to no longer use it, and besides, It will still be in the family.

I'll be heading over to his place during the upcoming holidays so as soon as I grab it, I will try to get good photos.

IIRC the tube in his is a Brimar CV4004 labeled HK. I'll have to re-confirm that since its been 6 months since I looked at it.

One thing certain, Those blew away the new ones easily.

Trout

[tom_dunham]

glad to hear that your brother is relenting and you will get the Tubeman.

Brimar tube huh?

BTW, I feel confident that I put pots in correctly based on my perusal of a bunch of old schematics.

pictures tomorrow

[tom_dunham]

Pictures!

I've included the inverse for clarity.

I think I will try an old Mullard ECC82... I'll post my impressions

[tom_dunham]

I gues the limitation to 100k is cumulative...

BTW ECC82 sounds really great - gives the pedal way more head room and makes the gain adjustment on Rock and Blues much more useful. Also, the pedal has noticably improved it's touch sensitivity. I think this is the best it has ever sounded.

[tom_dunham]

Picasa Web Albums - Thomas Dunham

download for full size image.

Thanks!