Transparent Drive? Should you care?
It's long been a buzz word in the guitar pedal world. I hope this helps offer a peak behind the scenes from an electronics nerd's perspective about what this means.
Usually, transparent overdrive means that the pedal adds dirt, but EQ is unchanged. Also, sometimes it refers to picking response, is it dynamic or compressed? My guess is a lot of the hype around transparent overdrives is in contrast to the classic Tube Screamer, which has a prominent mid boost and somewhat compressed clipping character. That's not bad of course, different strokes and all that.
Ok, so how does one get transparent EQ from a drive pedal? Sounds easy enough, just clip the signal, but keep the EQ flat. But here's the rub... clipping inherently affects the EQ. Clipping by default adds higher frequency harmonic content. So if you clip low frequencies, you end up with harmonics in the low mids that can sound muddy and crowded. If you clip high frequencies, you end up with even higher harmonics that can sound brittle and harsh. Furthermore, some components (op amps, transistors, fets) will become overloaded when driven hard with a lot of bass content, which even further muddies the sound.
Common strategies to combat these phenomena:
- Cut low frequencies BEFORE clipping — avoid the muddy lows
- Cut high frequencies AFTER clipping — tame the harsh highs
Most OD/DIST pedals do these cuts to varying degrees/at different frequencies. The way they're implemented goes a long way to shaping the sound. Some pedals cut bass and treble to the extent there is a strong mid boost. Some do it just right so that the result sounds like the EQ hasn't been changed at all. One thing is for sure, if a circuit just adds clipping without adjusting EQ at all, it won't sound very transparent at all, more like boomy and ice-picky. You have to change the EQ to preserve the EQ ... if that makes any sense.
Pedal Selection Considerations:
-Is transparent really what you want? Strat into a Fender amp with scooped mids and sparkling highs? A perfectly transparent drive might sound too thin, and a slight mid bump may be just right. Using a more mid-focused amp? Transparent OD may be just the thing to increase dirt without the mids going overboard. And of course style of music and just plain personal preference play a big role.
-Does the pedal have treble and bass controls? Treble (or tone) knobs are very common, bass knobs are less common. The existence of these doesn’t guarantee it’s a transparent sounding drive, but they do often go a long way in helping you shape how the EQ behaves at different gain levels. Knobs labeled ‘Voice’ usually affect the balance of mids to lows which can also help with this.
So what about the Anvil? The Anvil wasn't necessarily intended to be a perfectly transparent overdrive, since other pedals exist which cover that role brilliantly. I would say there are some transparent type tones in there, depending on knob settings, but it's always adding a little something to your tone. The Voice knob tilts the balance of EQ toward mids and highs as it’s increased. Now in terms of response, I do find that the jfet configuration really lets your picking dynamics shine through.
All in all our aim was a great sounding, unique, versatile tool. Whether people on the internet consider the Anvil 'transparent', only time will tell. Mainly we just hope you like how it sounds.