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Hoffman Amps Forum image Author Topic: Installed a Metro FX Loop. Are these kinda bright or is it just me (my circuit)  (Read 3691 times)

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Offline hesamadman

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Hey guys. Its been a minute since I have been on here. I dont have as much internet access living in the sticks.


So I have a pretty cool amp that I built. Two channels with independent gain, EQ, and MV. I installed a metro FX loop today. Since its a two channel amp, I installed it after the MV just before the PI. It is a standard cathode follower tone stack with MV. The loop works as it should but I feel like (at least on the gain channel) its very bright. I know some tone change is to be expected as it probably cant be 100% transparent, but I wasnt sure if what I have is just how it is, or if there are some things I should (could) do to maybe the PI input?

Offline shooter

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Quote
I have a pretty cool amp that I built

Then you have a schematic so we can help ?
Went Class C for efficiency

Offline PRR

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> its very bright. ... if there are some things I should (could) do

Wear sunglasses.

We can't see it from here. We can't know if you put in a too-bright light, or too-shiny reflector, or are playing in a coal-bin at midnight so it just seems bright by contrast.

Offline sluckey

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Did you look here?

     http://forum.metropoulos.net/
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline 2deaf

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The Metropoulos loop has an input impedance of 2.2M and a very flat frequency response, so it is unlikely that the loop itself is causing extra brightness.

Offline hesamadman

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I did originally look at metro forum. I couldnt get anything to load. That forum is so flakey, which is why I never used it. I looked again this morning and the site loaded and confirmed my fear. This is loop should be installed between the treble out and MV. Not after the MV. Unfortunately, this is a two channel amp and I can not do that. The MV becomes just a send pot. I guess I need to re-think this.

Offline leroy

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What about buying another effects loop and having them switch too? That would allow you to run different effect on each channel

Leroy

Offline pdf64

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In the absence of a schematic, everyone else is in the dark.
Perhaps the amp's arrangement is such that the tone after the master was being muffled, and inserting the loop acts to buffer things and eliminate that mufflement.
« Last Edit: May 09, 2018, 06:16:56 pm by pdf64 »
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