ISP Decimator II and G-String hum problem

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Re: Question regarding ISP Decimator II and G-String

Post by bitsleftover » Sat Aug 20, 2016 7:12 pm

Ah, I thought it was the G-String he had tried. Probably the best way to move forwards then. Expensive but money well spent if it solves the problem.

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Re: Question regarding ISP Decimator II and G-String

Post by Spacerocker » Sat Sep 03, 2016 11:21 am

Much as I am a fan of the ISP Decimator, I don't think it is going to help this problem! I have only read the first and last pages, and from what I can gather, the ISP decimator is doing its job, it's just that there is a low-level hum superimposed on the guitar signal. Get the ISP to switch off just above the hum level, and you kill the guitar signal too!

As others have said, the best solution it to get rid of the source of the hum, or play in a different location! My thoughts are:

1) Play straight into the amp, with no effects infront (not even the decimator), and physically remove any effects from the loop (don't just use the bypass switch). Is the hum still there? (I think this has been tried, and hum remained?)

2) Check all guitar leads are of good quality and well screened.

3) Change the power cord to the amp to eliminate a loose earth

4) Make sure other appliences (including power supplies) in the room are off

5) The LP Trad pick-ups pick up a surprising amound of noise and hum! I believe there is a technical reason for this - to do with them not being 100% humbucking by design?- -neverthe less they are a lot more noisy than HB pick-ups in my other guitars!. Make sure you are not standing next to anything, including all computers, laptops, even your own amp! We once spent 15 minutes at a gig trying to fault find a hum issues that was simple caused by me standing too close to the PA Amp!

6) Check the wirng in the basement. If necessary, switch off ALL the power at the circuit board, and run an extension lead in from upstairs. does that cure it?

Good luck!
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Re: ISP Decimator II and G-String hum problem

Post by gtrjunior » Sun Sep 11, 2016 7:43 pm

A slightly older thread now but...
Today I was messing around with some pedals with my amp (Splawn QR). I few in the loop and a few up front. I grabbed a power strip that I've had FOREVER and it had always worked great. But today I started getting the exact hum that the op described in this post. There is a clip he posted on pg 3.
After a couple minutes of jiggling wires to find the cause, I realized it was the power strip. When I wiggled the wall warts connected to the strip the humming varies from not too bad to sounding like a swarm of bees....I switched out the power strip to an almost brand new one and my rig was silent again....just another possibility for the op to consider if he hasn't already fixed his issue.

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Re: ISP Decimator II and G-String hum problem

Post by BigD. » Mon Apr 10, 2017 12:29 pm

I also had a weard hum when palm muting a note. I searched and searched but nothing.
Now after 2 years i bought a truetone Ispot pro c12 power supply and the hum is gone ( ... ro-c12zzz/).

I also use the decimator 2 g-string. No hum or noice anymore. I couldn't be more happy :D!

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