EH Holy Grail whine EZ repair

Paul Arntson · Post by **Paul Arntson** » 28 Jan 2012 4:41 pm

My Holy Grail pedal has had a bit of high pitched whine for a while. It got worse and I finally got sick of it and opened it up. Not much in there to look at. Surface mount board, but it is wired as true bypass.

I soldered a 0.1 uF capacitor from the output of the circuit board to ground and voila the whine went away! No other effect on the tone.

One thing, since it is true bypass, you have to put it before the bypass switch so it is only in the circuit when the effect is on. Otherwise it entirely eats the treble from the guitar. (You can't just put it across the output jack in other words.)

I thought somebody else might find this discovery useful. There are a lot of reviews on the web where people complain about this problem. It's an EZ fix for sure. Now we'll see if it lasts.

Rick Contino · Post by **Rick Contino** » 28 Jan 2012 5:28 pm

Interesting.

Slightly off topic, but would anyone happen to know why the reverb on my Holy Grail doesn't start working till the dial is turned up halfway? Are there any fixes for this problem?

Thanks,

Rick

Lane Gray · Post by **Lane Gray** » 29 Jan 2012 6:15 am

Mine appears almost the same, but since it sounds real sweet with the knob at about 1 o'clock, I never worried about it.

Paul Arntson · Post by **Paul Arntson** » 29 Jan 2012 11:19 am

If it's stable and not drifting in where it wants to be set, and if it makes the right sound, I'd be inclined not to mess with it.

I have a hunch some of the surface mount parts on there may not be exactly mil-spec if you know what I mean.

The whine on mine had gotten worse over the last two years, and it finally got to me. I figured I wouldn't use it as is so it was no loss if I messed it up fiddling with it. I just happened to get lucky.

Todd Brown · Post by **Todd Brown** » 29 Jan 2012 12:05 pm

How 'bout some pics, Paul. That would be most helpful for anyone having this problem.

Paul Arntson · Post by **Paul Arntson** » 29 Jan 2012 1:09 pm

That's a good idea.

Here you go.

Hope these are useful to someone.

Here's a more closeup shot:

Actually, any value cap from 330 picofarads on up would have worked. I tried a bunch of values with a cap sub box and then found a bag of 0.1 uF sitting on the bench.

Todd Brown · Post by **Todd Brown** » 29 Jan 2012 1:15 pm