Larmar pimv on front of amp? Noise issues??

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Larmar pimv on front of amp? Noise issues??

Post by texwest » Sat Jan 12, 2019 4:58 pm

I think I put this thread in the wrong place so copying here too.

I installed the ppimv on a guy's 1974 Marshall on the back panel but now he wants it on the front. I did a little research and found an old thread here where it sounds like putting it in one of the input jacks is a bad idea and introduces noise. There was mention of putting it in the presence hole and moving the presence to the back.

What is the best option or should I avoid moving the ppimv to the front completely?


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Re: Larmar pimv on front of amp? Noise issues??

Post by shakti » Sat Jan 12, 2019 6:14 pm

I always put it in the front panel and have had no issues.

You may have to get a little creative to fit it, and it depends on the amp which hole fits the best. You do want to keep the cable runs as short as possible.

One thing I've done which I think is cool and neat is to replace the two volume controls with a dual ganged 1M pot, and use the empty hole for the master volume. The downside is that Vol II will always be turned up along with Vol I, but a lot of people do that anyway. The upside is that the master volume will have a front panel position and will be labeled Volume.

A bonus feature if you use a dual 1M pot with a DPST switch (that was all I could find, actually) is that you can use the switch to do a cascade mod. Search for R/T mod. There are a few minor variations over this. I dig it as a bonus feature, in the right amp it can sound terrific.
JTM45 RS OT, 1973 18W, JTM45/100, JTM50, JMP50 1986, JMP100 "West Coast", AC15, AC30, BF Super Reverb, Boogie Mk 1, Hiwatt CP103, DR103

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