Marshall - GV-01 Guvnor: 1st series [schematic]

[deltafred]

... But, the pedal is quiet compared to everything else on my board. Even with all of the controls up on full, there is a drop in volume. Any ideas??

What clipping diodes have you used as they directly affect the maximum output level.

Silicon will be way down on LEDs with germanium and Schottky even lower than silicon.

[nooneknows]

Could anyone owning a real Guv'nor confirm the statement below?
In every schematics I've seen about the Guv'nor or its sons (danelectro Daddy-0, MI Crunch Box for example) the cut freq of the second stage is between 1K and 2K,

thank you,
M

IIRC there is a component error on the Marshall schematic that Ice-9 posted.

C8 should be 22pf not 220pf.

I worked with a guy who used to work at Marshall and he gave me the schematic that I built one from.With 220pf the top end response 3db point is about 1kHz so there is next to no treble. 22pf ups it to about 10kHz.

[deltafred]

Could anyone owning a real Guv'nor confirm the statement below?
In every schematics I've seen about the Guv'nor or its sons (danelectro Daddy-0, MI Crunch Box for example) the cut freq of the second stage is between 1K and 2K,

thank you,
M

IIRC there is a component error on the Marshall schematic that Ice-9 posted.

C8 should be 22pf not 220pf.

I worked with a guy who used to work at Marshall and he gave me the schematic that I built one from.With 220pf the top end response 3db point is about 1kHz so there is next to no treble. 22pf ups it to about 10kHz.

Build it with a 220pF and see if you like the sound.

[nooneknows]

Build it with a 220pF and see if you like the sound.

I have a Danelectro daddy-o (with the tone stack correction mod) with a 220 pF on second stage, when I put a 47 pF it became shrill. And the guv'nor haven't even any output buffer to eventually tame the highs, so I got curious.

btw, I didn't intend you're not saying the truth, just wondering if there could be different versions around

[deltafred]

Build it with a 220pF and see if you like the sound.

I have a Danelectro daddy-o (with the tone stack correction mod) with a 220 pF on second stage, when I put a 47 pF it became shrill. And the guv'nor haven't even any output buffer to eventually tame the highs, so I got curious.

btw, I didn't intend you're not saying the truth, just wondering if there could be different versions around

I originally built it using a 220pF and it was just all mud, the high and mid controls had virtually no effect because there was no frequency content for them to operate on.

Changing to 22pF made all the difference, you can still get the "all mud" sound as before by cutting the mid and high but can also get some usable sounds as well. You can also get shrill if you so desire.

Maybe the Danelectro daddy-o (I have no experience with it so am just speculating) used the schematic with the error, then they had to modify the tone stack to try and get some treble back. When you changed the 220pF to 47 it just became a treble booster.

The guy who gave me the schematic said there was the error on it, which I believed once I heard it.

There could be different versions but my schematic is identical to the one that Ice-9 posted.

[ansil]

IIRC there is a component error on the Marshall schematic that Ice-9 posted.

C8 should be 22pf not 220pf.

I worked with a guy who used to work at Marshall and he gave me the schematic that I built one from.With 220pf the top end response 3db point is about 1kHz so there is next to no treble. 22pf ups it to about 10kHz.

i just have one question then if it is supposed to be a 22pf then why did marshall put 220pf in all their boxes???????? well all of mine and everyone i have worked on that is. but i do agree it opens up the sound quite a bit. but if you keep the stock values and just change the pots to 25k it works on a whole new level. btw yes i own one, and have repaired those crappy traces and dc jacks on them for years and everyone of them has had 220pf. btw if you change out the ic for a tlc2262 you will get oscilation even with that cap but you will get a much more organic crunch

[deltafred]

... and everyone of them has had 220pf.

That is very interesting.

Maybe the guy that told me was wrong, or maybe it was an unofficial mod. I haven't seen him for years and don't have any contact details.

[ansil]

yeah i dont' know why but if you look at stomp box theory the guvnor is quite unique. with the cap on the gain control you get a variable high end depending on the gain settings. and usually the second stage is more a recovery stage in two gain stage pedals. however on the guvnor it rolls off quite a bit of high end and increase the gain more than a usual second stage. so in theory it makes it more amp like due to the inhereint high freq loss that would occur with the speakers. but starts it at a much lower freq so there is some tonal shaping that can still be done in the actual amplifier stage. how many pedals have you seen that have way too much high end fizzle that you can't seem to dial it back on the amp. also there is the old trick of using your pedals straight into a power amp stage like a lot of us do. i love the guvnor for that, the tone for days and days. i actually built a modded guvnor with a mosfet buffer and tlcc2262 chip as my preamp on one of my old amps straight into 100w mosfet section. it was crushing.

[andregarcia57]

there is difference between the guvnor I pedal and master drive?

[ansil]

assume you are referring to the drivemaster and you're asking a question. yes there is a difference although very slight

[Bernardduur]

The first version, the original unit that sounds so 'special' and good!!

I've read the discussion between the 'Made in the UK' version and the 'Made in Korea' version, so I just put the two together.

Made in the UK:

Made in Korea:

The values are all the same; the IC is in both a Motorola TL072

I don't hear a difference, only a small one that can be explained by a different setting of the potmeters........

[Bernardduur]

With the schematic;

[Dirk_Hendrik]

You are mistaken my friend.

It seems that you are so unfortunate as to be the very last individal on the globe who dos not know (even my mother-in-law does) that the Taiwanese version does use poor quality components. How it was determined that te quality of these components was poorer is yet to be found out but stating so does increase resale value of the UK model. Therefore it must be true. Furthermore how the inventory guys at Marshall managed to ensure the Taiwanese model would contain poorer quality components is to be determined just as well. I'm willing to place a good bet they were completely oblivious of this at the time.

All 'n all,
Thanks for your conclusions which I personally will not doubt for a second. However, these conclusions must be incorrect, since many "want to believe".

[uncleboko]

Consider 2 lead guitarists in a band each using a Marshall Guvnor, one Taiwanese and the other a UK model, playing at earsplitting volume of course. I guarantee you couldn't tell who was playing the Taiwanese and who was playing the UK model, because they will sound exactly the same

[GodSaveMetal]

The first version, the original unit that sounds so 'special' and good!!

I've read the discussion between the 'Made in the UK' version and the 'Made in Korea' version, so I just put the two together.

Made in the UK:

DSCF4173.jpg

Made in Korea:

DSCF4172.jpg

The values are all the same; the IC is in both a Motorola TL072

I don't hear a difference, only a small one that can be explained by a different setting of the potmeters........

Please post the photos of the PCB side, please please man!!! thanks!

[kroaton]

The removal of C22 is a very good mod for this pedal.

[Ice-9]

The removal of C22 is a very good mod for this pedal.

Wrong pedal, no C22 in the Guv'nor I assume you are talking about the little guv'nor2 pedals not the excellent sounding Guv'nor that this thread is about.

[storyboardist]

I drew up a perf and PCB layout for the Guv'nor and thought I'd share it here. Uses board mounted right-angle PCB pots (from the solder-side of the board) and should fit in a 1590B just fine.

[uncleboko]

Cleaner version of the circuit