Marshall - SV-1 Supervibe Chorus  [schematic]

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hgamal
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Post by hgamal »

I've got a Marshall Supervibe SV-1 but it is not working. Does anybody has its schematics?

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Post by Valve Head »

Here are the schematics for the SV-1. This should get you started.
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Marshall SV1.PDF
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roseblood11
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Post by roseblood11 »

How do you like the sound of that pedal? Is it worth making a layout?

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JiM
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Post by JiM »

I'll have to look at it more closely, but the principle looks similar to the chorus in the stereo Valvestate amps.
For example, there are two LFOs, one of which is controlled by the RATE pot. The SWEEP pot mixes the constant LFO and the variable LFO.

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Post by Dirk_Hendrik »

roseblood11 wrote:How do you like the sound of that pedal? Is it worth making a layout?
I'd say no. These buggers are too cheap to go through the hassle of DIY.
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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Post by roseblood11 »

How is the bypass sound? I know the Vibratrem and the Guvnor2 from the same series, and they are tonesuckers.
A better buffer could be a reason to make a clone - or at least a mod for the original pedal...

Other idea: Is it possible to get a flanger sound out of this pedal? Chorus and Flanger are very similar circuits...

As a diy-layout would be quite large, a bb-enclosure would be needed anyway. So, it would make sense to have second footswitch to switch from chorus to flanger...

I saw this idea in this pedal: http://uk-electronic.de/onlineshop/prod ... 8a9a223116
But I guess that it´s digital (PT2399?) and a similar effect build around the mn3007 would be more interesting.

I listened to some samples of the SV-1 and I really like the sound of that little bastard, it would be a good starting point for a more complex pedal.

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Post by hgamal »

Valve Head wrote:Here are the schematics for the SV-1. This should get you started.
Thank you very much!

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Post by modman »

Moved from Requests to Modern Stompboxes
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Post by guitarist »

I notice that this isn't true bypass at all! With my board and a Pete Cornish style tube buffer this thing goes way bright and a tad boosted when activated. So just wondering how I can draw that down so it plays fair.

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Post by Andy2No »

I had trouble finding the PDF manual for one of these, which I like to have. I found plenty of links from googling, but they all turned out to be a link to a dummy file, containing another link, to a .exe installer - very dodgy.

So, I emailed Marshall and they sent me this (It's no longer on their website and hasn't been for a while). I asked permission to post it in a forum but never got a reply, so I'm taking that as a yes. If they, or anyone else, feels it should be removed, then please do, though I can't think of a good reason for doing that. Mostly, I hope to provide a google search result that does actually lead to downloading the manual, and doesn't lead to probably contracting a virus, or installing a trojan.
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SV-1 SUPERVIBE.pdf
Marshall Marshall SV-1 Supervibe owners manual
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roseblood11
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Post by roseblood11 »

I love the sound of this pedal, but it never found its way onto my pedalboard, because of the background hiss. I guess it's caused by the 4066 that is used for the switching. Any ideas how to solve this?

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Post by Andy2No »

I only bought one recently, roseblood11, so I've only played with it briefly. I haven't noticed the hiss, so far. I have noticed a fairly large level boost when I turn it on, which I wasn't really expecting.

Could it be your power supply, or does it do it on a 9V battery too? Some pedals are more sensitive to that than others.

I normally use an 8 cell AA NiCd or NiMH pack fed through a 1A LDO 9V regulator - an LM2940T-9.0, with the usual capacitors to smooth it. That's a very low noise power supply (when run on the NiXX packs), compared to most wall wart style ones.

The Boss wall wart is supposed to be good (based on a youtube video comparison I saw), but it's a lot of money, for just a 200mA or so supply - I could probably make half a dozen of mine, for the same price, and I already had quite a few of those battery packs.

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Post by Andy2No »

Have you checked the link in your signature recently, roseblood11? It doesn't work for me.

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Post by roseblood11 »

Andy2No wrote:Have you checked the link in your signature recently, roseblood11? It doesn't work for me.
It#s dead since the german musikding forum runs with a new software. I#ll have to upload all my files again.

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Post by Andy2No »

roseblood11 wrote:
Andy2No wrote:Have you checked the link in your signature recently, roseblood11? It doesn't work for me.
It#s dead since the german musikding forum runs with a new software. I#ll have to upload all my files again.
I see. It's now http://musikding.rocks/wbb/ but I guess they cleared it all out and started again.

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Post by AuditoryDriving »

wtf monday, this is a nuts and bolts forum, not a nuts and bots forum.

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Post by roseblood11 »

Has anybody tried to improve this chorus in the meantime? It has some interesting tonal options, but with that tone sucking in bypass mode and all the hiss when it's on, it's not really usable.

Maybe replacing the cmos switching with a 3pdt and higher quality output buffers could help.
I made this silly looking layout for a Dimension - P chorus, but it should fit into te SV-1 easily.
Image

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Post by roseblood11 »

I'd like to convert this pedal to true bypass, omit the second output and cut out the "jack pcb" completely. But I don't really understand, how the circuit on that jack pcb works.
Is "delay out" on the main pcb the output of the circuit? Or is that just a signal with vibrato, which has to be mixed with the direct signal on the jack pcb to get chorus? (schematic is in post #2)

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