Paul Cochrane - Tim pedal  [traced]

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Post by puppiesonacid »

modman wrote:Had we gotten around to tracing Paul C's Tim, we would have had an example schematic to look at.

Image

But interesting thread, will move this one in the FAQ folder

oh, didn't even know that one had an effects loop... h mmmm what happend with planning to trace that one out?


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Post by modman »

puppiesonacid wrote:
modman wrote:Had we gotten around to tracing Paul C's Tim, we would have had an example schematic to look at.

But interesting thread, will move this one in the FAQ folder
oh, didn't even know that one had an effects loop... hmmmm what happend with planning to trace that one out?

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We just never got around to it... nobody offered to dissect his Tim... maybe this is an invitation.
The original, general topic on send/returns in effect boxes is still in the FAQ folder here

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Post by paulc »

Well - no need to take apart a tim. That's already been done with the timmy, so I'll add the rest since it'll be done anyway...

The main section of the tim is like a timmy but with a 500ka gain control. The loop is simple. Take the output off the wiper of the volume control, and send it to the tip of a switching jack. That's the send jack. The switching contact goes to the tip of a mono jack, and also to the foot switch. The mono jack is the return. That jack also has a 510k resistor wired from tip to sleeve. This is like a bleeder resistor on a true bypass switch, but it's there to de-pop the output of a pedal that's plugged into the loop. The volume pot acts as that resistor for the send.

When you plug into the send jack it lifts the switch contact not letting the signal pass to the footswitch. Instead what makes it to the footswitch is the signal coming in from the return jack.

The reason i did this was because I built the pedal for my old plexi, but when i used it with my twin it didn't have enough mids to make it rock. I liked using the old MXR 10 band to up the mids, but that pedal didn't have a footswitch - you couldn't turn it off. Putting in the loop solved that problem for me.

There's also an "extra" feature that wasn't planned on. If you take a cable out of the send jack, but don't come back into the return that acts like a "wet" output with the normal output jack having the bypass sound. It's like a simple A/B box with one side getting the distortion. It's not great though because it doesn't mute the channel not being used.

And before it's said - yes i know it's been done before me.

The boost section started life as an odd mid boost circuit. Another tap was taken off of the inv input of the opamp clipper and taken to the boost footswitch. The switch then went to an 82mh coil in series with a 10ka pot in series with a 330ohm resistor. Then to a .150uf cap and to the 1/2 pwr point. The junction of the.150uf and the 330 ohm tied over to the bass controls 1uf with a 10ka pot. This had a res sound sort of like a mild notched wah effect. That's the way the original pedal was done back in '97. over a couple of years I'd sometimes add a switch shorting out the coil to remove the res sound, and then i dumped the coil all together to get what's made now.

That's it - simple.

Later, PaulC

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Post by seniorLoco »

Cheers Paul :thumbsup
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Post by puppiesonacid »

thanks paul, that helps to give me some insight on effects loops. If you search for my post about how to put effects loops into pedals you'll get where I was coming from. But thank you for sharing that information, really!!! :D


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Post by Wagster »

I have a TIM and love it.At $150 it's a good deal.It's one of the best OD's I've heard through my AC30.

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Post by briggs »

8) Great Stuff PC!

I've always liked the marshall "Contour" control when playing with the mids in a signal path. Did you ever look at using that in conjunction with your Tim circuit?
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Post by sevinisthenumber »

paulc wrote:Well - no need to take apart a tim. That's already been done with the timmy, so I'll add the rest since it'll be done anyway...

The main section of the tim is like a timmy but with a 500ka gain control. The loop is simple. Take the output off the wiper of the volume control, and send it to the tip of a switching jack. That's the send jack. The switching contact goes to the tip of a mono jack, and also to the foot switch. The mono jack is the return. That jack also has a 510k resistor wired from tip to sleeve. This is like a bleeder resistor on a true bypass switch, but it's there to de-pop the output of a pedal that's plugged into the loop. The volume pot acts as that resistor for the send.

When you plug into the send jack it lifts the switch contact not letting the signal pass to the footswitch. Instead what makes it to the footswitch is the signal coming in from the return jack.

The reason i did this was because I built the pedal for my old plexi, but when i used it with my twin it didn't have enough mids to make it rock. I liked using the old MXR 10 band to up the mids, but that pedal didn't have a footswitch - you couldn't turn it off. Putting in the loop solved that problem for me.

There's also an "extra" feature that wasn't planned on. If you take a cable out of the send jack, but don't come back into the return that acts like a "wet" output with the normal output jack having the bypass sound. It's like a simple A/B box with one side getting the distortion. It's not great though because it doesn't mute the channel not being used.

And before it's said - yes i know it's been done before me.

The boost section started life as an odd mid boost circuit. Another tap was taken off of the inv input of the opamp clipper and taken to the boost footswitch. The switch then went to an 82mh coil in series with a 10ka pot in series with a 330ohm resistor. Then to a .150uf cap and to the 1/2 pwr point. The junction of the.150uf and the 330 ohm tied over to the bass controls 1uf with a 10ka pot. This had a res sound sort of like a mild notched wah effect. That's the way the original pedal was done back in '97. over a couple of years I'd sometimes add a switch shorting out the coil to remove the res sound, and then i dumped the coil all together to get what's made now.

That's it - simple.

Later, PaulC
I wanna make the boost side for a single pedal on my board... I love my Tim but I just wanna have the boost in a separate enclosure for a small board of mine! Is there a schematic??
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Post by bajaman »

thanks for the info Paul :thumbsup
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Post by sevinisthenumber »

sevinisthenumber wrote:
paulc wrote:Well - no need to take apart a tim. That's already been done with the timmy, so I'll add the rest since it'll be done anyway...

The main section of the tim is like a timmy but with a 500ka gain control. The loop is simple. Take the output off the wiper of the volume control, and send it to the tip of a switching jack. That's the send jack. The switching contact goes to the tip of a mono jack, and also to the foot switch. The mono jack is the return. That jack also has a 510k resistor wired from tip to sleeve. This is like a bleeder resistor on a true bypass switch, but it's there to de-pop the output of a pedal that's plugged into the loop. The volume pot acts as that resistor for the send.

When you plug into the send jack it lifts the switch contact not letting the signal pass to the footswitch. Instead what makes it to the footswitch is the signal coming in from the return jack.

The reason i did this was because I built the pedal for my old plexi, but when i used it with my twin it didn't have enough mids to make it rock. I liked using the old MXR 10 band to up the mids, but that pedal didn't have a footswitch - you couldn't turn it off. Putting in the loop solved that problem for me.

There's also an "extra" feature that wasn't planned on. If you take a cable out of the send jack, but don't come back into the return that acts like a "wet" output with the normal output jack having the bypass sound. It's like a simple A/B box with one side getting the distortion. It's not great though because it doesn't mute the channel not being used.

And before it's said - yes i know it's been done before me.

The boost section started life as an odd mid boost circuit. Another tap was taken off of the inv input of the opamp clipper and taken to the boost footswitch. The switch then went to an 82mh coil in series with a 10ka pot in series with a 330ohm resistor. Then to a .150uf cap and to the 1/2 pwr point. The junction of the.150uf and the 330 ohm tied over to the bass controls 1uf with a 10ka pot. This had a res sound sort of like a mild notched wah effect. That's the way the original pedal was done back in '97. over a couple of years I'd sometimes add a switch shorting out the coil to remove the res sound, and then i dumped the coil all together to get what's made now.

That's it - simple.

Later, PaulC
I wanna make the boost side for a single pedal on my board... I love my Tim but I just wanna have the boost in a separate enclosure for a small board of mine! Is there a schematic??
Anything??
"The man who says he knows everything will never know the truth"
C.S. Lewis

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Post by paulc »

sevinisthenumber wrote:
sevinisthenumber wrote:
paulc wrote:Well - no need to take apart a tim. That's already been done with the timmy, so I'll add the rest since it'll be done anyway...

The main section of the tim is like a timmy but with a 500ka gain control. The loop is simple. Take the output off the wiper of the volume control, and send it to the tip of a switching jack. That's the send jack. The switching contact goes to the tip of a mono jack, and also to the foot switch. The mono jack is the return. That jack also has a 510k resistor wired from tip to sleeve. This is like a bleeder resistor on a true bypass switch, but it's there to de-pop the output of a pedal that's plugged into the loop. The volume pot acts as that resistor for the send.

When you plug into the send jack it lifts the switch contact not letting the signal pass to the footswitch. Instead what makes it to the footswitch is the signal coming in from the return jack.

The reason i did this was because I built the pedal for my old plexi, but when i used it with my twin it didn't have enough mids to make it rock. I liked using the old MXR 10 band to up the mids, but that pedal didn't have a footswitch - you couldn't turn it off. Putting in the loop solved that problem for me.

There's also an "extra" feature that wasn't planned on. If you take a cable out of the send jack, but don't come back into the return that acts like a "wet" output with the normal output jack having the bypass sound. It's like a simple A/B box with one side getting the distortion. It's not great though because it doesn't mute the channel not being used.

And before it's said - yes i know it's been done before me.

The boost section started life as an odd mid boost circuit. Another tap was taken off of the inv input of the opamp clipper and taken to the boost footswitch. The switch then went to an 82mh coil in series with a 10ka pot in series with a 330ohm resistor. Then to a .150uf cap and to the 1/2 pwr point. The junction of the.150uf and the 330 ohm tied over to the bass controls 1uf with a 10ka pot. This had a res sound sort of like a mild notched wah effect. That's the way the original pedal was done back in '97. over a couple of years I'd sometimes add a switch shorting out the coil to remove the res sound, and then i dumped the coil all together to get what's made now.

That's it - simple.

Later, PaulC
I wanna make the boost side for a single pedal on my board... I love my Tim but I just wanna have the boost in a separate enclosure for a small board of mine! Is there a schematic??
Anything??

The boost section is laid out in the last section above. It's all there.

I don't think it's going to work for you though. It's a gain boost for the clipper circuit. It's not the same as a stand alone boost slamming into something. That would increase the signal level going into a pedal instead of increasing it's gain. The boost mode is part of the clipper.

PaulC

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Post by drmathprog »

PaulC;

How's the new Fender-friendly pedal design coming?

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Post by ryanuk »

paulc - Many thanks for the info you provided on your TIM design; I have some clarifications on the info you've given, if I may.
paulc wrote:The main section of the tim is like a timmy but with a 500ka gain control.
Whats the affect of choosing 500ka for the TIM, as opposed to 1Ma for the TIMMY.
paulc wrote:The boost section started life as an odd mid boost circuit. Another tap was taken off of the inv input of the opamp clipper and taken to the boost footswitch. The switch then went to an 82mh coil in series with a 10ka pot in series with a 330ohm resistor. Then to a .150uf cap and to the 1/2 pwr point.
I assume the 10ka pot refferred to here is the DRIVE pot loctaed on the rear of the TIM.
paulc wrote:The junction of the.150uf and the 330 ohm tied over to the bass controls 1uf with a 10ka pot. This had a res sound sort of like a mild notched wah effect.
I assume this 10ka pot is the TONE control on the rear of the TIM.
paulc wrote:That's the way the original pedal was done back in '97. over a couple of years I'd sometimes add a switch shorting out the coil to remove the res sound, and then i dumped the coil all together to get what's made now.
For clarification, the boost circuit currently used is that described above but simply with the coil removed and "jumpered".

regards

RyanUK

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Post by Ben N »

I'm guessing the different gain pot values are because the Timmy can have it's entire gain range in that one pot, while the Tim has to keep some gain in reserve for the boost--the gain pot is a feedback resistor, after all. As Paul has expressed here before, he designed these so the second stage does not get overdriven - IOW not to have any icky opamp distortion. BTW, Paul, I asked John Greene about the boost in his now-discontinued Glasspack OD (a TS/FD2 variant with mosfet clipping), and the way he handled that was to stick a pair of clippers-to-ground with a high threshold (LEDs, maybe) after the main clipping section, so that normally they would have no effect, but when boosting they would limit the signal downstream, while adding some additional distortion and compression on attacks.

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Post by TheLemon »

Would the TIM's boost/tone and effects loop look anything similar to this?
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Post by TheLemon »

Image

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Post by ryanuk »

TheLemon wrote:Image
This schem looks pretty consistent with PaulC description. One minor criticism however - the send jack for the loop should be a switching jack, not TRS jack as pictured. Otherwise you wont be able to get the switching described as follows;
paulc wrote:Take the output off the wiper of the volume control, and send it to the tip of a switching jack. That's the send jack. The switching contact goes to the tip of a mono jack, and also to the foot switch. The mono jack is the return. That jack also has a 510k resistor wired from tip to sleeve. This is like a bleeder resistor on a true bypass switch, but it's there to de-pop the output of a pedal that's plugged into the loop. The volume pot acts as that resistor for the send.

When you plug into the send jack it lifts the switch contact not letting the signal pass to the footswitch. Instead what makes it to the footswitch is the signal coming in from the return jack.

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Post by nyto_one »

I bought a Tim used for 200€ and I've finally the overdrive after which I ran for over 200 years. I had OCD, Plextortion, TS9, Fulldrive2, GT500, Lovepedal Plexiglas, VPD1, Hotcakes, AC boost, BB Preamp, Trex Moller, Eternity ans many more...
But The only shiny m'y old 1968 Vox AC30 is the Tim!!!
Thank's a lot Paul from a little happy frenchies :-))
Les Paul on Vox with The Tim and Lovepedal Kalamazoo in help for solo and big riff, this is Paradise!!!
Paul, good job!!! ;-)

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Post by quaternotetriplet »

TheLemon wrote:Image

hey man, i think you missed the 82mh inductor

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Post by xampworshipx »

maybe this isn't helpful at all, but I found this on my computer:
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