post phase invertor effects loop

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jestaudio
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post phase invertor effects loop

Post by jestaudio »

something i,m thinking of for my current marshall style build particularly as a fair bit of the drive on the dirt channel seems to be created by the PI, i,ve been tube rolling for a couple of hours and found that a hi gain tube in the pi position gives me a lot more gain when pushed, in order not to muddy the sound up it seems only resonable to insert the effects after the PI,???????????????
Gaz
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Re: post phase invertor effects loop

Post by Gaz »

Not gonna happen :) But seriously, I think this is why the pros run some of there effects post-mic on their vintage amps. This might be even more elaborate than a hypothetical post-PI effects loop because it requires at least one employee.
9pins
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Re: post phase invertor effects loop

Post by 9pins »

you have to make a differential amp the whole way thru the gain structure...
or maybe sum both sides post PI as a send, then have another PI as the recovery, I guess the real issue is maybe just how practical the notion is.

You might be able to sum both legs to send and then use the cathode of a buffer/drive stage to mix. Interesting puzzle if it is possible.
there is a right way to mic a musical saw
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Reeltarded
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Re: post phase invertor effects loop

Post by Reeltarded »

1. Amp
2. Load box with a line out
3. Effects (NOT PEDALS)
4. Power amp
5. Speakers.

I prefer a simple unbuffered loop just before the PI for tone/feel EQ insert (if at all) and all the shaping EQ/pitch/time based bits come after the load box, ie; chorus, delays, reverbs.

If you have a multi-amp setup, it can get nicely complex. Sub-mix thru a small console, put all the dedicated effects on the loops there, and use the sends for global effects... but now we are talking about crazy shit that should never be spoken of... by normal people.

Wheeeeeeeee!
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
jestaudio
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Re: post phase invertor effects loop

Post by jestaudio »

Reeltarded wrote:1. Amp
2. Load box with a line out
3. Effects (NOT PEDALS)
4. Power amp
5. Speakers.

I prefer a simple unbuffered loop just before the PI for tone/feel EQ insert (if at all) and all the shaping EQ/pitch/time based bits come after the load box, ie; chorus, delays, reverbs.

If you have a multi-amp setup, it can get nicely complex. Sub-mix thru a small console, put all the dedicated effects on the loops there, and use the sends for global effects... but now we are talking about crazy shit that should never be spoken of... by normal people.

Wheeeeeeeee!
Since when to amp builders qualify as norma; :lol:
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Reeltarded
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Re: post phase invertor effects loop

Post by Reeltarded »

Ahhh...

Internet. ;)
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
John_P_WI
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Re: post phase invertor effects loop

Post by John_P_WI »

A properly designed and installed FX loop should not color or muddy the sound. A marshall type circuit is probably the easiest of all to implement an FX loop to.

Look here for a very simple approach:

https://tubeamparchive.com/viewtopic.ph ... =plexi+evh

BTW, you could easily tweak an FX loop for a little more gain as well, giving you the drive that you want.

I would highly discourage an "after the PI loop", there is too much happening there with bias and signal phase etc.
jestaudio
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Location: UK

Re: post phase invertor effects loop

Post by jestaudio »

John_P_WI wrote:A properly designed and installed FX loop should not color or muddy the sound. A marshall type circuit is probably the easiest of all to implement an FX loop to.

Look here for a very simple approach:

https://tubeamparchive.com/viewtopic.ph ... =plexi+evh

BTW, you could easily tweak an FX loop for a little more gain as well, giving you the drive that you want.

I would highly discourage an "after the PI loop", there is too much happening there with bias and signal phase etc.
i,ve tried inserting a reverb inbtween the output of the master and the phase inverter which seems to work ok, now i,m just trying to sort out running both channels into the PI wthout interferance, the pecularity of my amp is the channels are fed into either side of the PI
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