Metro Loop install

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studiodunn
Posts: 293
Joined: Wed Nov 24, 2010 8:50 pm

Metro Loop install

Post by studiodunn »

I'm putting a Metro Loop into my 100watt 2 channel FrankenBassman and have a question.
The amp is 2 channels feeding the PI off of a relay, with a PPIMV.

So hooking the loop up, do I just disconnect the relay feed to the PI input and route it to the send/out of the loop and then run the return/in to the PI input?

I'll use the loop for both channels. I'm also wondering if I need to add a coupling cap at the PI input. The amp currently has each channel/preamp with a coupling cap into the mechanical relay and the relay feeding the PI direct, but I'm thinking the loop, having make-up gain would need a coupling cap going into the PI.
Stevem
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Re: Metro Loop install

Post by Stevem »

What effects are you looking to turn thru the loop?
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studiodunn
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Re: Metro Loop install

Post by studiodunn »

I'm using it for all my time based effects and potentially to run an Atomic Amplifire through.

I got it up and running last night, so to answer both my questions and possibly help any others in the same situation. Yes, that's how it hooks up to a circuit and yes it needs a post loop/pre PI input coupling cap. I used a .022uf cap.

The loop sounds great BTW and really is an easy addition. Pics coming.
Stevem
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Re: Metro Loop install

Post by Stevem »

You should note that time based effects sound terrible if like in your case your may be add distortion after them by clipping the PI and or output stage!
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!

Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
studiodunn
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Re: Metro Loop install

Post by studiodunn »

Stevem wrote: Tue Feb 28, 2017 5:58 pm You should note that time based effects sound terrible if like in your case your may be add distortion after them by clipping the PI and or output stage!

This 100 watt beast it is all preamp distrotion as the power section is being choked and not pushed. I also run a 12AT7 in the PI of this amp to tame the gain. It's also much more musical to my ears - in this amp.

Can you please help me understand where I am adding the distortion? I'm still learning all of this piece by piece. Thanks.
Stevem
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Re: Metro Loop install

Post by Stevem »

So your master volume is before , or after the PI?
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!

Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
studiodunn
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Re: Metro Loop install

Post by studiodunn »

Stevem wrote: Wed Mar 01, 2017 12:05 pm So your master volume is before , or after the PI?
After
pdf64
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Re: Metro Loop install

Post by pdf64 »

If there's no channel master vol before the PI, then you'll probably be overdriving the PI, it may be the most significant clipping stage.
So fx added at the loop would still get mushed up.
Not ideal, and it may make setting suitably low reverb / echo levels tricky, but if it's giving results that you can use then that's all that matters.
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studiodunn
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Re: Metro Loop install

Post by studiodunn »

Thank you and understood now.. There is actually a channel MV Pre-PI, so I assume that is taming signal into the PI and allowing the FX to play nicely with the loop.
It sounds great BTW and has really helped my overall signal by making the Delay, trem and Verb much more controllable.

I do have a bit of pop when engaging, but that may be something that needs fixed in the pedal.

Thanks for the insight everyone.
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