DOD-308 YJM Guitar Overdrive
Posted: May 7, 2009
So after swapping out the opamps in my Metal X
I was wanting to follow what my friend
Jeff Blevins did and mod a DOD YJM308
Yngwie Malmsteen (my favorite guitar player :) pedal.
So I swapped the opamp out (another 4558 as I suspected) for two
different OPA's. Luckily, unlike the Metal X, the OPA2604 worked in
this circuit and actually I think this my fave of the three.
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Sample Sound Files
So here are some sample mp3's I made. I played the YJM directly through
a Sovtek amp with no reverb or anything so the pedal can be heard in its
rawest form. I think the 4558 sounds really dry and kind of boring
and doesn't have much gain at all.
The OPA2134 sounds a bit nicer, but the OPA2604 just sounds.. just
the best of the three. More gain, bigger sound. For the pedal settings,
I had the gain on full and level halfway up for all 3 tests.
I was just playing some random crap (some power chords/some single note
leads) with the pickups in both bridge and neck to show the different
sounds this pedal can make. I think these recordings don't sound as
good as they could since the volume level on the Sovtek is down really low.
The next three recordings were made with the set up below: The Yngwie
wanna-be guitar connected to the DOD YJM308 pedal modded with the
OPA2604 set with the gain 3/4's up and the level a little over halfway up
connected to a digital delay (for a little reverb) connected
to a Mini Marshall amp cranked at full volume. Cranking the power amp
makes a huge difference.
yjm_minimarshall1.mp3 (Some crunch chords from Hiroshima Mon Amour)
yjm_minimarshall2.mp3 (Some twangy lower notes from Now Is The Time)
yjm_minimarshall3.mp3 (Some random leads just because)
Pictures and Explanation (Click for a bigger image)
Here is the ultimate Yngwie Malmsteen wanna-be kit. Here's a Squier strat
(not even a real strat) modified with Yngwie's old DiMarzio HS-3 pickups
in all 3 positions and the
fretboard scalloped, a Mini-Marshall amp,
and the DOD YJM308 Yngwie wanna-be pedal.
Here's the guitar pedal opened up.
This is the pedal ripped to pieces.
Here is a close-up of the PC board. The 4558 is still there in this picture.
I removed this chip and replaced it with a socket so I can swap opamps
in and out to try different ones.
Here are the opamps. The far left is the OPA2604, the next over is the
4558. The thing to the right of the opamps is a socket. I soldered this
in so I could swap out opamps without resoldering them.
This is the setup I used to record the last 3 mp3's above. I think this
guitar pedal sounds the best when the main amp is cranked to full volume.
I couldn't do that with the first 3 recordings since my neighbors would
probably kill me. The Mini Marshall however isn't so loud and actually
sounds pretty decent.
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