EHX HolyGrail Classic R1 Resistor Issue

[Ricoche]

Hello everyone,

Today I acquired a free Classic EXH HolyGrail pedal from a music store here in Japan.  It was broken so the sales clerk just gave it to me knowing I've had some experience with fixing a few things in the past. 

Using the correct adapter, it powers up and I can hear my instrument just fine either in bypass or effect mode.  The problem is that I get no reverb effect and when I turn the dial clockwise, the volume decreases probably because the effect is not working on the reverb side.  I opened up the unit and removed the PCB board.  On the bottom side I noticed a burnt area on the PCB board at R1.  Attached are three photos that hopefully give you an idea of what I'm looking at.

My question is whether you think this is fixable or should I perhaps just junk it and move on.  I have some basic knowledge of soldering and have repaired a number of keyboards, but I'm not entirely confident about properly diagnosing some areas of electronics.

Thanks in advance for info that might help me to determine whether I should proceed in fixing this box or whether it might be more work than necessary.

Jim

http://jimatwood.files.wordpress.com/2012/07/ehx-holygrail-1.jpg
http://jimatwood.files.wordpress.com/2012/07/ehx-holygrail-2.jpg
http://jimatwood.files.wordpress.com/2012/07/ehx-holygrail-3.jpg

[theehman]

R1 is a 4.7ohm, 1W SMD resistor.  I often recommend the fix that this one has, but with a higher wattage resistor.
I would replace the op-amp just below the Blend control.  That may fix your problem.

[Ricoche]

Fantastic!  Thank you very much for the info.

Jim

[R O Tiree]

@ Ron - I'm wondering, given the amount of thermal damage to the board, whether it might be worth replacing C1 and C2 as well?

[theehman]

I wouldn't worry about it.