what is the effect of a rectifier?

[Z3R0T0N1N]

hi
i know basically what the rectifier does in modular environments like synth edit, but can someone tell me what it is used for in production? Like what would i use the GVST Grectifier for, for instance?

thanx for any help, and if you could put it in simple terms (for a simple mind ) i would be most greatful.

cheers
-g

[shamann]

Distortion. Specifically like octave distortion pedals.

[AdmiralQuality]

Tychobrahe Octavia (think Purple Haze)

[bool]

In tubeamp power supply, it's often regarded as provider of "motorboating" effect (sag).

[AdmiralQuality]

In tubeamp power supply, it's often regarded as provider of "motorboating" effect (sag).

That's a different rectifier, for converting AC wall current to DC to power your tubes. He's asking about one in the signal path. A full wave rectifier. Like Jimi's Tychobrahe Octavia pedal.

[Muff Wiggler]

a rectifier converts alternating current (AC) to direct current (DC). DC doesn't have negative values.

If you had a sine wave centered around zero crossing, a 'half wave rectifier' would flatten out the sub-zero portions, and leave the greater than zero portions, in effect removing half of the signal with each pass of the waveform - you'd have the same number of peaks as the original, but none of the troughs.

a fullwave rectifier would actually convert the negative troughs into positive peaks, so you'd have twice the number of peaks.

[shamann]

Here's what a sonogram will look like. This is a 100 Hz sine wave plus the rectified signal. The sine wave is the bottom line, all the added harmonics are what the rectifier gives you:



The bit on rectification is pretty good on this page:

http://www.geofex.com/effxfaq/distn101.htm

[AdmiralQuality]

So how do I get one of them purple light sabres?

[shamann]

When Darth Vader and Obiwan make sweet jedi love.

Rectify!

[Stupid American Pig]

pull it out of yer rectum?

[mistertoast]

A recent discussion sent me looking for the old plug Octaver. Finally found it. It's my favorite plug for dropping a guitar by an octave.

When I was looking for it, found a recent update (2005) of TapeStop, my favorite uh, tape stop effect.

Sometimes you just get lucky.

[AdmiralQuality]

Like this you mean?

[AdmiralQuality]

A recent discussion sent me looking for the old plug Octaver. Finally found it. It's my favorite plug for dropping a guitar by an octave.

When I was looking for it, found a recent update (2005) of TapeStop, my favorite uh, tape stop effect.

Sometimes you just get lucky.

Back to seriousness....

"Octavers" aren't rectifiers. Rectifiers will create an octave-up effect. Octavers that create an octave down usually work by a flip-flop circuit that creates a square wave that's half the pitch of the incoming signal. A rectifier doesn't re-create the waveform in this way, it just folds the bottom half back up.

To play Octavia you'll usually want a very "smooth" sound going in... neck pickup played around the 12th fret for guitarists. Anything "bright" will come out sounding very trashy. And chords get completely destroyed.

[shamann]

A recent discussion sent me looking for the old plug Octaver.

The tbt Octaver? It isn't a rectifier though, it's actually a pitch shifter.

[mistertoast]

>>"Octavers" aren't rectifiers.

Yeah, I know. I just was reminded of that conversation by this one. Sorry for the off road detour.