The Electro-Harmonix Knockout Attack Equalizer is a two-filter combination pedal that has one low-pass filter, one high-pass filter plus a direct signal control. It’s claimed to make “your Les Paul sound like a Strat and your Strat sound like Tele” by using a seven-pole filter for sculpting the low end of the mid frequencies and a six-pole filter for sculpting the top end.
It’s a typical Electro-Harmonix pedal, with the usual home-made look about it, but don’t be put off – this unassuming and cheap little box has been cleverly thought out. By carefully balancing the three controls against each other there are a myriad of tonal colours to be had, most not available on an amplifier tone circuit. Although there’s obviously no memory option, it would be easy to mark up with a piece of tape where the particular sweet spots for any favourite tone characteristics are. I deliberately started with a Telecaster after reading the press blurb as I didn’t want to immediately start making one guitar sound like another; I wanted to hear what the pedal sounded like. With the Low control about two o’clock, the Dry control about 11 and the High about nine, the Tele took on some fat mids which – although still nice and clean – beefed up what was a thin sounding guitar. By keeping the Dry signal out of it and boosting the Low and High, I acheived a really credible electro- acoustic sound. You have to be careful though, the tone I got by boosting the High and knocking out the Low and the dry was beyond thin and actually, quite painful on the ear. However, this high-pass effect could be useful in a recording situation by being able to add the very top end to a dull sounding acoustic guitar by just playing the part again and mixing it in.
Plugging a Les Paul was interesting. No, before you ask it didn’t sound like a Strat with the Knockout Attack Equalizer pedal, but to be honest I don’t really think they meant it. What they were trying to say was that with the Knockout, a humbucker-equipped guitar can approximate a single-coil-equipped LP by boosting the top-end and scooping out some of the mids and lows. The pedal is actually very good at this, and I can see that that’s what it will mainly be used for. Again, I could produce a believable electro- acoustic sound from the Les Paul, something no amp is capable of.
With a Strat, the Knockout added some sparkly top end, but again I had to be careful with the High control. The pedal will work with the overdrive or lead channel of an amp, but unless you want special effects, I would advise that the Low and High controls are used sparingly
In between the extremities of the controls on this pedal are some very useful settings. It can be used for beefing up or adding sparkle and all points in between. The Electro-Harmonix Knockout Attack Equalizeris an affordable and very useful stompbox for guitar or bass – take a look.