I have never been a fan of outboard EQs for guitar amplifiers and that applies especially to cheap outboard EQs such as those made by Boss. In the pro audio world that I work in an EQ is seldom used for anything more than to make the system flat. In other words, the EQ is used to make the system respond to all frequencies equally, no one frequency louder than the other. After that then channel strip EQs or side chained EQs are used to change the overall response of the particular instrument or voice.
All that being said a guitar is not FOH and when a player say's they need an outboard EQ to find the tone they want, then what they're really saying is;
"Either one of my effects pedals is killing the tone of my rig, or I have the wrong amp speaker combination to begin with."
Outboard EQ's may well help with the problem but the old addage "Nothing for nothing" surely applies.
The first issue will be the enhanced gain in the signal chain. The overall effect of this enhanced gain will always be that every pedal following the EQ will have it's properties change, which is why an EQ should come last. Second, the EQ will certainly add to the noise floor in the form of hiss. and the additional gain will usually result in feedback of the wrong kind.
Try this. Take all of your pedals out and plug right into the amp. Play through every channel at a decent volume and ask yourself if any of the tones come close to what you want. Use the amps tone controls. Can't get close? You have the wrong amp. Getting close? Keep trying. Then start adding effects in this order.
Tuner
WAH
Compressor
Overdrive
Delay
Chorus, etc.
And the myth. Not everything needs true bypass. Many effects units pass tone without loss, some do not, some actually enhance tone even though they are not being used, and the reason for adding effects one at a time is to pinpoint the effect in line causing the most damage to your tone.
The problem with having a signal chain that is fully bypassed is that the length of the cable run to your amp could actually double. The math is simple, just add the length of cable to the affects, bypass them all (no buffer) and add the cable length to the amplifier, and that could add up to 40 -50 feet. So what's wrong with that? The impedence/capacitance changes and so does the tone. Why not just add another capacitor to the tone circuit of your guitar, say .047, that should make it nice and muddy don't you think?
So sorry for the rant but adding is subtracting in guitar world IMO, and adding an EQ is just a crutch for poor tone to begin with. However if you absolutely must add the EQ, then add it to the effects loop and suffer that tone sucking loss, but be sure to add a good one. DBX makes a good line of EQs. I use the 2231s for FOH and sound work because of the added features, however a simple single channel with a gain control will do you well. And please, don't waste money on a Behringer unit.
Good luck, have fun.
http://www.dbxpro.com/131/131.php
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