Clark - Gainster (big box) / Barber

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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JHS
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Post by JHS »

IC is a JRC 072BD in the original G., but Clark used another type too.
The JRC sounds excellent in the G., very clear, yet warm and dynamic with tubelike breakup.

IMHO nothing comes close to those green PIO caps and the CC Rs produce some distortion too. W/o the PIO caps my G.-clone sounded average (I used MF caps for my prototype) but with those PIOs it sounded way better and more dynamic.

SOZO caps are a real good substitute for the green PIOs and SOZOs are not so hard to get.

JHS

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soulsonic
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Post by soulsonic »

What's the big deal with SOZO caps anyway? They look like any other polyester cap to me. I've use old mustard caps before and I didn't hear anything magic...

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DougH
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Post by DougH »

Well, I tried it again last night and all the troubles I was having were due to that bad pot. That fixed the "icepickiness" and it has a nice full and smooth sound now.

I really like this thing. I mean really like it. It produces an "AC/DC crunch" when the gain is maxed. It doesn't generate much distortion, but it doesn't need to. It's not really about the "distortion" on this one. With my "mini AC15" running clean and alnico speaker it sounded great. With the gain and presence around 50% it made my amp sing in a real nice way. It responded really well to my fingers and it was real easy to get notes to bloom into higher octaves and sustain . I love having that kind of finger control. I had the output level set to around 1/3 so I wasn't driving the amp- the pedal circuit was basically doing it.

Tried some cap swaps- I swapped my .047 presence cap with a pair of .022 mallory 150's in parallel, and heard no difference. I tried an orange drop in place of the .1 film input cap and preferred the film cap.

I used an LF353 op amp. I have not tried swapping around the op amp yet. All in all, this is a great sounding overdrive that does not have the EQ issues of a TS. It has a well balanced frequency response and a nice open sound.

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Post by soulsonic »

Wow Doug, you've actually piqued my interest in building one!

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MKB
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Post by MKB »

soulsonic wrote:What's the big deal with SOZO caps anyway? They look like any other polyester cap to me. I've use old mustard caps before and I didn't hear anything magic...
They are very useful in a Marshall amp build. I built a 50W clone using Orange Drop caps, and struggled with it for over a year to get some of the fizziness out. Replacing the Orange Drops with Sozos cured the problem in one shot, and gave it more of a Marshally midrange response. Not sure how useful they would be in an effects pedal though.

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Post by soulsonic »

MKB wrote:
They are very useful in a Marshall amp build. I built a 50W clone using Orange Drop caps, and struggled with it for over a year to get some of the fizziness out. Replacing the Orange Drops with Sozos cured the problem in one shot, and gave it more of a Marshally midrange response. Not sure how useful they would be in an effects pedal though.
But you could probably observe exactly the same phenomenon with Mallory 150s vs. Orange Drops. I've been using 150-type polyester caps in most of my amp and pedal builds for a couple years now, and they've consistently had a good tone regardless of brand. I've used Mallory, CDE, Illinois, and unbranded generics and they pretty much all sound the same - I don't expect that the SOZO ones would be much different.

I believe that it's the wrapped polyester style itself that sounds better, not necessarily any specific brand. Why would I pay $2.25 for a single 100nF SOZO, when I could get the same Illinois MWR for $.35 or a Mallory150 for $.50?

I'm sorry, I have yet to be sold on SOZO's mojo. I'm not anti-mojo either; I love carbon comp resistors and paper-in-oil caps, but they haven't convinced me what makes their version of the same ol' yellow polyester aluminum foil cap is better than anyone else's.

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Post by celadine »

In my limited experience, the same type of cap from different companies can sound very different (depending on the circuit, etc.). YMMV.

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Post by tomtom »

I love paper in oil caps and AB carbon comp but I was really disappointed with the Sozo caps, not a nice bandwith and crappy midrange.

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Post by DougH »

I've used Mallory, CDE, Illinois, and unbranded generics and they pretty much all sound the same - I don't expect that the SOZO ones would be much different.

I believe that it's the wrapped polyester style itself that sounds better, not necessarily any specific brand. Why would I pay $2.25 for a single 100nF SOZO, when I could get the same Illinois MWR for $.35 or a Mallory150 for $.50?
I agree. I use these type caps in amp builds and grab whatever the surplus place has. Sometimes they are Spragues, sometimes they unmarked generic. I have Mallory's too. They all pretty much sound the same.

I don't agonize over cap types in pedals, other than to stay away from ceramics. And in a 9v circuit, the only thing CC resistors do is add noise, to my ears.

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Post by polarbearfx »

its interesting this looks so similiar to the menatone red snapper, and the red snapper got most of itself from boss. It just goes to show you that IP is just silly and from the begining all circuits were borrowed from each other. It continues today on the boutique front. Its kind of cool actually but people that get upset about it are in some ways crazy.

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Post by soulsonic »

polarbearfx wrote:.....but people that get upset about it are in some ways crazy.
I think they are totally crazy.
"Analog electronics in music is dead. Analog effects pedal design is a dead art." - Fran

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Post by DougH »

I'm not familiar with the Red Snapper but there are fairly substantial differences between the Gainster and the Boss OD-1 IMO. The presence control is a nice touch, for example. Well, maybe the differences aren't that substantial. I don't know... It's all relative I guess. The Bluesbreaker is two op amp stages too, non-inv followed by inv, etc...

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Post by sosodef »

Does anyone have a schematic for the original barber big box overdrive?
Its the boss od-1 minus the buffer and with the presence control?

I know the schematic posted is the modified version, I just want to see the original.

Also I wonder if the presence control might be better being a dedicated tone stack??

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Post by JHS »

The schem shows the org. circuit of an early Gainster. Mike used JRC 072BD and NS 353N. The circuit was traced from the gut shot Dan had posted in Aron's forum.

Mike built at least five different circuits over the years. Caps, bias divider and Vol. pot value are different in later circuits to suit customers tastes. Acc. to him and on customers demand some custom versions had been built too with slightly different circuit design.

80% of the unique sound comes from those old hard to get PIO caps and w/o them you only gain the sound-quality of the Barber made Gainster or Red Snapper.

I breadboarded all kown G-circuits and the circuit shown on the schem sounded best to me and. acc. to Mike it's his favorit G-circuit.

JHS

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Post by sosodef »

ok I see the right side features a mod but the rest is stock.
JHS what do you think about dumping the presence knob, and throwing in a different tone stack?

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Post by JHS »

Add another RC-combination to IC1a (4.7k/100n or something like this) and subs the P-pot for a 25k trimpot (Barber uses this a lot in his circuits)

Swap the 22k on IC1b for a 25k pot + 3,3n - 10n cap like in the 4-knob Snapper, this will not alter the basic sound of the Gainster at all.

The advantage of this tone control is that gain and bass are not altered any longer if treble is decreased.

JHS

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Post by sosodef »

There is a used barber gainster for $80 I was going to pick it up. Is it the same circuit as the clark version?

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Post by JHS »

Barber used a newer G-circuit for development and cheaper caps for his G. Acc. to Mike the cheaper caps were part of the deal with the distributor to archieve a low sales price and the box (dimensions are also part of the deal) is to small for fitting big, expensive PIO caps.

The Barber G. is bassier and not so direct sounding as the first Gs. Soundwise it is more a G. V4.

JHS

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Post by AfterDarkMusic »

Hey guys. I'm a complete noob at this stuff, but I'd love to give this build a try. What the heck is going on with the bold spot marked 'N'? I've asked a few people who have helped me out before and no one seems to know. Is it simply a spot labeled 'N' where you connect all three of those marked points? Thanks a lot ahead of time for any help.

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AfterDarkMusic
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Post by AfterDarkMusic »

After looking at a few more schems, it looks like it's the bias. Now, are these points simply all connected or is there a certain technique that needs to be used?

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