I frequently mention how much I like my modified Boss GE-7. I keep coming back to this pedal as a booster.
Anyway, I knew all along a good parametric EQ would be a better choice. TO reminded me of this on the forum, and so I brought one. Single band parametric EQs are available as pedals, but multiband ones are rare, and tend to be rack units. Spec-wise the Boss PQ-3B would seem to be about the best compromise between features and user friendliness, and I was lucky enough to find one on ebay.
Affect on tone when inserted and switched off
There is a small but noticeable bass loss. High end is hardly changed. Unusual for a Boss pedal.
Affect on tone when switched on and controls in a neutral position
Slight volume increase. Marginally more pronounced "presence" range. Negligible increase in noise.
In use compared to standard GE-7
Overall the pedal is alot less noisy than a standard GE-7, I also believe its a bit more transparent. +18dB of clean boost is useful, and its a nice clean boost too!
I expected the 'Low' and 'High' controls to be shelved EQs, in fact they are band EQs. It would be *much* nicer to have these as shelves in my opinion.
Setting the controls to extreme settings increases the noise of course, but its less than a standard Boss GE-7. The 'Q' of the filters is a little bit nasty - I put this down to cheap capacitors used. I wanted to set the controls for a largeish bass roll off, a light treble roll off and a mid boost, with the output level maxed out. Thats how I use my GE-7.
The bass roll off is easy enough to dialin - the parametric EQ makes it easy to do in a good way. Using with a bass rather than electric guitar I found I could dial in some cool tones using this control too.
Treble roll off was not quite so satisfying, the slightly nasty Q and the band rather than shelved nature of this control meant the results were a little unpredictable with electric guitar. With a bass this control was more usable, but occasionally ice-picky. Treble was nice through my JMP50 than the Lead 12.
I found using the mid control for getting a modern 'scooped' sound on bass and electric was very easy and satisfactory. That was fun for a while, but I wanted to boost the mids in general. Boosting the mids did not give nice or predictable results. Even with a minimal boost it sounded very wah like.
So overall I'd say this would be a nice pedal for a modern metal bassist or guitarist. It sounded better than an standard GE-7 and was lower noise etc etc. Cool scooped sounds, great control over bass frequencies.
For those looking for a more classic boosted mid sounds I wasn't so keen, it ended up sounding artifical however I dialled it in.
Modding thoughts
Obviously the PQ-3B sucked life out of the tone compared to my modded GE-7, and was noiser. I also noted the Q of the filters was a bit nasty. Of course modding could address these issues quite easily with new op-amps and capacitors.
Opening the pedal revealed a relatively simple circuit with 6 inline opamps. Perhaps Monte Allums chip adapters could be used. The capacitors were easily accessible.
Would modding make mid boosts more usable? I think so, but it would need a lot of experimentation which I don't have time for. A great mod would be to change the bass and treble controls to be shelves.
Will I trade my modded GE-7 for a standard PQ-3B
No
Will I trade my modded GE-7 for a modded PQ-3B
Don't know - but I have my doubts. Both pedals have their uses.
How would I design a parametric EQ pedal for guitar?
Low - shelf EQ, one knob controls cutoff frequency
High - shelf EQ, one knob controls cutoff frequency
Mid - full parametric EQ with cutoff frequency, Q and boost
Level - one knob controlling boost with a wide range bias towards boost. -12 to +24dB maybe
I think a single band parametric EQ with nice bass shelf and overall level control would have its uses too.
Relative ratings
Standard GE-7 7/10
Standard PQ-3B 8/10
Modded GE-7 9/10
