EBS - Multicomp  [schematic]

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Sweetalk
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Post by Sweetalk »

I'm looking the schematic of this pedal for reparing. A Friend broke the Active/Passive switch trying to open it to take some pictures, here are some!:

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Sweetalk
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Post by Sweetalk »

Sorry for the double post but, I fixed it... I tried to replace the switch and didn't work, replaced it by a jumper and didn't work also. The jumper was shorting a via hole. Now it's working. I hope you like the pictures, let me know if you need something from the pedal while I still got it!. :mrgreen:

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seele
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Post by seele »

*bump* 8)

Any news about the schematic?

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Sweetalk
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Post by Sweetalk »

seele wrote:*bump* 8)

Any news about the schematic?
I don't have this anymore with me so I can't trace it. The pictures aren't so good to do this, sorry!!

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seele
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Post by seele »

I borrowed this cool little pedal for a week and couldn't resist to open it.
The photos aren't the best but i managed to desolder the pots and write down some of the labels.
http://picasaweb.google.com/derseele/Mu ... 9094293106


Labels:

left upper side (under comp/limit pot)
TL064c
WT4-5n

The orange ones next to the switch
47516k542
v474t366

the black ones next to the switch
3fw-4n (2x)

right side under gain pot
jtp-51
rc4558 58m c92ng4
orange one 475-16k-542

near dc jack:
big one lt050sig
2x L4P
jtp51 (3x)

Hope this helps somehow...

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seele
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Post by seele »

Nah, forgot to mention this is the version without True Bypass...

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supracat
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Post by supracat »

Hi,
I have same problem with this switch in my Multicomp, so I wanted to ask you how did you fix it? Did you find a replacement for this switch?
Thx, :D

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Sweetalk
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Post by Sweetalk »

supracat wrote:Hi,
I have same problem with this switch in my Multicomp, so I wanted to ask you how did you fix it? Did you find a replacement for this switch?
Thx, :D
In my local electronics store had the same switch. I just propper replaced it and worked like a charm.

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lolbou
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Post by lolbou »

You can find such switches in Marshall amps too... I once had some from their french distributor (for cheap and delivered at my local guitar shop).
- Are you a mod or a rocker?
- Uh, no, I'm a mocker.

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Post by seedseed »

This compressor is really good for bass has anyone managed to get a schematic from somewhere for it?

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Vicus
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Post by Vicus »

I have one of this with some problem, if someone have the schematic please send me a copy. Thaks.

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Post by pedalgrinder »

hi everyone

where are we at with this one is there to much surface mount for a schematic to be put together. i can't seem to put enough detail together from those photos to have a crack would be nice to have one to have a go at. has anyone attempted a schematic yet???? This one would definately be a good one for the bass players as what i've read on the reviews its definately one of the better compressor out there. Can someone let me know what stage this thread is at??/
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Post by pedalgrinder »

don't everyone respond at once. :slap:
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Post by ryanuk »

pedalgrinder wrote:Can someone let me know what stage this thread is at??/
Pedalgrinder

You gotta have a little more patience. It doesn't look like anybody is currently running with drafting a schematic. Probably cause of the complexity of the boards (doubled sides, lots of SMD).

I think anyone undertaking to RE this one, would need the pedal in front of them for the best possible chance. There's just too many hidden tracks.

RyUK

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Post by Liquids »

pedalgrinder wrote:hi everyone

where are we at with this one is there to much surface mount for a schematic to be put together. i can't seem to put enough detail together from those photos to have a crack would be nice to have one to have a go at. has anyone attempted a schematic yet???? This one would definately be a good one for the bass players as what i've read on the reviews its definately one of the better compressor out there. Can someone let me know what stage this thread is at??/
"Two in the hand is worth one in the bush"

The Carl Martin comp is pro-level using the best THAT chip available, one used in a few rack mounted compressors and should be more than adequate for bass, and there are schems/projects/etc here....

Feel free to buy one and take pictures yourself...DIY (Do It Youself) vs DIFM (Do It For Me), you decide...

Remember that the grass is always greener...where the cows 'fertilize' it :mrgreen:

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Post by pedalgrinder »

yeah fair enough. I apologise for my impatience i just assumed with so much information there that someone was on it i was just trying to find out or see if i could help. I do like to give it a go and help rather than just sit back and let everyone else do the work. But those pictures would be almost impossible to trace a schematic. Cheers
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Post by farbiondriven »

Hi everybody, im here searching for some help, i really dont know what to do more :D

I do some repairing jobs on pedals, and someone gave me a broken ebs multicomp. It had a melted-down power-supply section, which i fixed, replacing a 100 R resistor, and removing the 100 uf filter capacitor.
The pedal worked fine. I gave it back to my customer, who broke it down again, supplying it with a 12v AC.

Now the pedal doesn't work, and it shows a 120 R resistance from Vcc and ground. The main problem of that device is that is ALL smd, very big trouble.

I REALLY need some suggestions :D

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farbiondriven
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Post by farbiondriven »

sorry, i havent read the rule about debugging. I've post it in the request section ! :)

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Post by iv4nosky »

Hi , I have a death multicomp ebs. Its looks like that theres a resistance wich is burned and also a smd wich (107 p81) referecen is written over it. Does anyone any reference of a smd to replace it? I tried google but with no result during hours. Here is a pictures of the components:

Image

Thanks

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Post by deltafred »

iv4nosky wrote:Hi , I have a death multicomp ebs. Its looks like that theres a resistance wich is burned and also a smd wich (107 p81) referecen is written over it. Does anyone any reference of a smd to replace it? I tried google but with no result during hours. Here is a pictures of the components:

Thanks
Is this any use?

https://www.freestompboxes.org/viewtopic ... 70&t=11143
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