Zendrive’s Voice Knob?
by Rhoy Pamparo on Feb.04, 2009, under Melodic Insights
I’ve been getting a lot of different answers as to what the voice knob for the Zendrive is supposed to do. So, to appease myself, I have plugged it in directly into Logic. I was watching the spectrum analyzer as I rotate the knob from left to right & right to left. I did that for a bit and I noticed that it seems to boost/cap the signal between 2Khz-6Khz region just before going into the gain circuit. So it’s then true, that the voice knob would affect the gain and the tone characteristics. The tone on the other hand is doing the same sort of thing but I think it is after the gain circuit.
DISCLAIMER: This is only my non-scientific observations!
What did I learn from all these? Nothing much really, but I did find a great setting for my Zen.
Gain – 2 o’clock
Voice – 2 o’clock
Tone – 11 o’clock
Volume – unity
So after I got bored, I realized that since I am already plugged-in, then I should be able to record! I was going to record the different settings of tone & voice combination but I did this instead:
No post-processing and it’s really sloppy … my playing that is! So I only recorded less than a minute to somehow also lessen my shame 
If you manage to survive listening to that, here are the settings for the following tracks …
Rhythm 1: Zendrive, Telecaster (Bridge PU)
Rhythm 2: Sparkle Drive, Empress Tremolo, Telecaster (Bridge PU)
Lead (wannabe): SFX-03 Channel 2, Diamond Delay, Telecaster (Neck PU)
Bass: I didn’t have my bass ready! Doh!
Drums: loop from betamonkey.com
February 4th, 2009 on 7:47 am
Glad you got it worked out!
You have my basic settings! I use what you have for harder-type rhythms, for lower gain, I turn the gain down to 10:30 and the tone to 1. Cleans up PERFECT and then has some nice crunch when you turn up the volume and play power chords!
I’ll listen to the clips as soon as I get home
February 4th, 2009 on 2:02 pm
Rhoy— thats what we gear geeks do— geek out on our buddy’s sites.
I got that info from a site where they take apart the pedals and give the schematics (piracy at some points) which came up when I did a search like: Zendrive Voice knob Function or something.
The guy had taken apart the Zen and explained that the tone was going in BEFORE the gain, and the voice shaped the Gain hump.
When I looked at the schematics and tried to follow them on my Zen through all the goop, it made sense to me.
(for those that don’t know, Hermida Audio- like most boutique makers- covers some of his vital “secret parts” in an epoxy-ish goo to prevent people from copying his design/piracy prevention)
So research through a pedal pirate followed by my own analysis (albeit a narrow one) of the circuit.
February 4th, 2009 on 6:37 pm
Hmm … interestingly enough, I also found a schematic of a zen clone that has the voice set to PRE-gain and also a post on gearpage that says the same thing. But definitely, it acts like an envelope/bandpass at the upper mid-range frequency.
I was hoping that Alf Hermida would respond to my inquiry on what the knob is originally designed/intended for.
February 5th, 2009 on 8:36 am
heh… wow, a lot of mystery!
If you get a response from Alf, let us know!
All I know for sure is that the voice really changes the distortion feel. But you already said that.
And its a great pedal.
May 3rd, 2009 on 10:04 am
zendrive is a soft clipping od, tone pot of the zen is same as fliter knob of a rat distortion… meaning after the clipping