Parallel effects loop for Marshall style amps

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novosibir
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Re: Re:

Post by novosibir » Thu Mar 25, 2010 4:27 pm

emartine wrote:You then have two 22n caps in series, Larry? :?
If the Master is dimed - yes! With a 1Meg to ground from between the .022's

Larry
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Re: Re:

Post by erigm » Thu Mar 25, 2010 5:34 pm

emartine wrote:You then have two 22n caps in series, Larry? :?
yeah, but that's not really different from most amps. you come right from you tone caps into the PI cap, right? And most amps with fx loops do the same thing as Larry is suggesting. I for one vote to have the master after the loop as well.
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Re: Re:

Post by emartine » Thu Mar 25, 2010 5:49 pm

novosibir wrote:
emartine wrote:You then have two 22n caps in series, Larry? :?
If the Master is dimed - yes! With a 1Meg to ground from between the .022's

Larry
Alright then! Thanks both of you.
Andrés Martinelli
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Re: Re:

Post by flemingmras » Fri Jun 04, 2010 11:03 pm

erigm wrote:
emartine wrote:You then have two 22n caps in series, Larry? :?
yeah, but that's not really different from most amps. you come right from you tone caps into the PI cap, right? And most amps with fx loops do the same thing as Larry is suggesting. I for one vote to have the master after the loop as well.
For proper gain structure that's the only place it belongs! This way your master controls the volume of the whole package with the effects already mixed in...not change the drive signal to the effects as doing it this way would alter the way the effects interact with the signal depending on where you have the master set.
There's just that fine line between stupid and clever - Nigel Tufnel

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Re: Parallel effects loop for Marshall style amps

Post by Tone Junkie » Mon Jun 07, 2010 9:40 am

Larry any chance I could get your loop . thanks Bill
at (jadesource@comcast.net)

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Re: Parallel effects loop for Marshall style amps

Post by mkdivine » Mon Jun 14, 2010 12:22 am

i'd like to know if this loop would work for my matamp gt1.
unfortunately, there are no shematics of the matamp gt1 available..
im looking for a solution since ages... i tried the kleinulator but i disliked how it changed my tone.
would a gut shot of my amp help?

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Re: Parallel effects loop for Marshall style amps

Post by emartine » Sun Oct 17, 2010 11:35 am

Larry: "When you try the Master after the loop section, don't forget the additional coupling cap! one .022 from the recovery stage's plate to the Master and another .022 to the PI's input."
Emartine: "You then have two 22n caps in series, Larry? :s"
Larry: "If the Master is dimed - yes! With a 1Meg to ground from between the .022's"

And if I choose to have the DPDT version as well, I would have three 22n caps round there. Am I right?

Im really into building this thing now that I finished college.
Thanks Larry!
Marshall for Tango

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Re: Parallel effects loop for Marshall style amps

Post by emartine » Thu Oct 28, 2010 5:30 pm

Larry, are you still there??? :s
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Re: Parallel effects loop for Marshall style amps

Post by novosibir » Thu Oct 28, 2010 5:59 pm

emartine wrote:Larry, are you still there??? :s
Don't worry!

I hear ya!
I see ya!
I even can smell ya!

But I can't always reply to all and everything 8)

Larry
The fault almost always is sitting in front of the amp :wink:

Larry's Website now with included Pix's Gallery

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Re: Parallel effects loop for Marshall style amps

Post by emartine » Thu Oct 28, 2010 9:51 pm

novosibir wrote:
emartine wrote:Larry, are you still there??? :s
Don't worry!

I hear ya!
I see ya!
I even can smell ya!

But I can't always reply to all and everything 8)

Larry
Ok, Larry. If you get a chance later, I would be very grateful if you could clarify that doubt I have. :wink:
Thanks!
Marshall for Tango

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Re: Parallel effects loop for Marshall style amps

Post by novosibir » Thu Oct 28, 2010 11:08 pm

emartine wrote:Larry: "When you try the Master after the loop section, don't forget the additional coupling cap! one .022 from the recovery stage's plate to the Master and another .022 to the PI's input."
Emartine: "You then have two 22n caps in series, Larry? :s"
Larry: "If the Master is dimed - yes! With a 1Meg to ground from between the .022's"

And if I choose to have the DPDT version as well, I would have three 22n caps round there. Am I right?
Correct!

1st from the bypass path to the Master's input
2nd from the loop's recovery stage also to the Master's input
3th from the Master's wiper to the PI's input

If you'd like to go 'advanced', then include the Master into the PI's grid-cathode-network and safe the one .022 from the wiper to the tube's grid. Confused now?

Simply remove the upper 1M resistor with a 1M pot, where the wiper goes directly to the upper tube's grid.
Then you only have the two .022's to the Master's input :thumbsup:

Keep in mind, that in this case the Master isn't referenced to ground!
The Master's ground lug in this case is connected there, where the remaining 1M, the 470 and the 10K are connected together.

Larry
The fault almost always is sitting in front of the amp :wink:

Larry's Website now with included Pix's Gallery

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Re: Parallel effects loop for Marshall style amps

Post by emartine » Sun Oct 31, 2010 1:29 pm

novosibir wrote:
emartine wrote:Larry: "When you try the Master after the loop section, don't forget the additional coupling cap! one .022 from the recovery stage's plate to the Master and another .022 to the PI's input."
Emartine: "You then have two 22n caps in series, Larry? :s"
Larry: "If the Master is dimed - yes! With a 1Meg to ground from between the .022's"

And if I choose to have the DPDT version as well, I would have three 22n caps round there. Am I right?
Correct!

1st from the bypass path to the Master's input
2nd from the loop's recovery stage also to the Master's input
3th from the Master's wiper to the PI's input

If you'd like to go 'advanced', then include the Master into the PI's grid-cathode-network and safe the one .022 from the wiper to the tube's grid. Confused now?

Simply remove the upper 1M resistor with a 1M pot, where the wiper goes directly to the upper tube's grid.
Then you only have the two .022's to the Master's input :thumbsup:

Keep in mind, that in this case the Master isn't referenced to ground!
The Master's ground lug in this case is connected there, where the remaining 1M, the 470 and the 10K are connected together.

Larry
Thanks, Larry. :rock:
Ill think Ill make the simpler version. :wink:
Marshall for Tango

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Re: Parallel effects loop for Marshall style amps

Post by emartine » Sun Oct 31, 2010 1:51 pm

My last question from now is if the 82k + 100k conjuntion from the PI is a good place to solder the Uc (4k7)..
Thanks once again!!
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Re: Parallel effects loop for Marshall style amps

Post by novosibir » Sun Oct 31, 2010 3:01 pm

Yes!
This even is the best point, to take off the supply voltage.

Larry
The fault almost always is sitting in front of the amp :wink:

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Re: Parallel effects loop for Marshall style amps

Post by axeman » Sun Oct 31, 2010 8:11 pm

Welcome back Larry. :worthy:

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