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am i correct to presume adding + or - 64 to a waveform via a mixer effectively dc offsets, or shits the entire wave completely postive or completely negative in value? this value is amplitude, correct?

if so then what is the difference between this and full wave rectification, where as i understand it the wave is pushed into completely values.

how would one go about doing half-wave rectification. where the negative portion of the wave is effectively choped off. leaving only the positive portion.

i have allready heard about obsidian mod1 stuffs that include a rectifier. i would rather know how to construct this via pre-existing mod2 modules. there is a thread in the developers section by defex which talks about building a rectifier in scope out of basic modules like mixers and other utilitarian modules availble in the moduarl. but it isn't detailed enough or mention what type of rectification is used to be of much understanding to me.

i'll email him if i don't get any replies here.

addimitedly i am more than likely tossing around terms in incorrect manners, correction would be appreciable.

the nord modular is very inspiring to read up on, the tutorials for it are really a great place to pool ideas from. i have visions of doing something similar with the cw modular....maybe.

thanks.

<font size=-1>[ This Message was edited by: castol on 2002-02-26 10:00 ]</font>

Full wave rectification is just taking an input and removing the negative sign if there is one. that way the signal is always positive.

i hope that makes sense.

to create a rectifier in modular you would need to take the input, split it in two,

signal 1:
offset it by +MAX (as you described with a mixer) that way the top of the wave will be "chopped off" then you need to ofset it by - MAX and then invert it.

signal 2: ofset by -MAX then +MAX

add 2 signals together.

as you can see this is a very klunky way to do it, that is why stecki made an atom that uses a lot less DSP (removes the - sign i expect)

I hope that helps.

<font size=-1>[ This Message was edited by: defex on 2002-02-26 10:29 ]</font>

thank you.

your right, this does look very clunky.

but usefull to know none the less!

beside getting the mentioned obsidian mod1 pack, any chance of something like this coming about from a third party, say yourself?

i have read cw is anti-modular, module device building or something of that sorts. to bad...

i'll have to probe them for their own commentary of this.

CW had mod1 open for additions. I suspect they will do more, or open mod2, at some later point. I wish it would happen sooner, once it does I think Mod2 will explode! Who would buy the Zarg Sequential atoms as a Modular2 pack?

i do not think thay are anti modular, they just have not gotten around to it yet. i am sure that is on the "b" list of things to do.

in fact it can probably be done with the right documentation.

anyways the only way would be to make a little device you could plug into an output and an input (i will have to experimant with this and check it will work polyphonically before a poly out module)

cw gets a lot of negative rep and speculation.

generally i think it is undeserved.

i was only passing on the vibe, infectious almost.

anyway it seems more reasonable that it is like you say "on their large list of things to do" i know i have one of those...and things get neglected more often than not....some people, even myself, interpret this as negative or uncaring.

i agree, when it does open to developers and some new modules come out, my modular life will be that much more grand.

in practice though the stock modules provide tons of flexibility. i am finding ways of using modules or combining others (as defex has shown) to do different things not exactly intentioned.

i'm a big fan of ring mods, bi-val constants, and 2 channel mixers. inverting, dc offsetting, and now half-wave rectifying...woo hoo!

Why would you want to rectifiy an audio signal? (Which is, if I understand correctly, "moving" it all above 0.0v[creating a huge DC offset?])

?

Thanks

for use with modulation sources and destinations. i'm sure there are many more interesting things you can use rectification for, but i am just looking for the abillity to deviate from the intentioned behavior of things, and derive slightly different mod signals from the same source modulator.




<font size=-1>[ This Message was edited by: castol on 2002-03-01 15:02 ]</font>

rectifying audio signal creates distortion with only even harmonics in output. it is used in many designs like Mesa-Boogie amps for example.
i believe that Neutron Harmonic DeStortion is built around those, check it out at devices page

thanks for the insight. i try to keep myself from downloading device after device, but thanks to defex i think i have enough knowledge to build something similar in the mod2. i think i spotted that someone else was building a patch with this type of rectified distortion. thought about mentioning it in my previous post but i don't remember who it was, atomic maybe?

On 2002-02-28 16:44, Michu wrote:
rectifying audio signal creates distortion with only even harmonics in output. it is used in many designs like Mesa-Boogie amps for example.
i believe that Neutron Harmonic DeStortion is built around those, check it out at devices page

actually NOT! it is a strange circuit that can do odd harmonics as well, it would never work without the rectifier though.

The harmonics change on the harmonic destortion depending on the input. the "number" is only rough for a sine.

try to explain it? no i cant be bothered right now. its a neutron secret anyways anyone could do it with Stecki atoms.



<font size=-1>[ This Message was edited by: defex on 2002-03-01 17:59 ]</font>

remember you can use mod1 mdl's in mod2, they just look funny, they still work

do you have the link where one can purchase these mod1 modules? i've run across it before, but don't remember the name of the pack, or even who released them.

my patches are tending to be very big and my screen real estate is at a premium, but i will give it some more thought. i only casually looked at the pack before, when i wasn't all that comforable with the modular.

thanks defex

defex, thanks for explaining
had no time to evaluate it fully, but it sure sounds good on bass

i am not sure about modular2 but in modular1 envelope follower with attack and release set to zeros works as full wave rectifier.

hey michu, thanks for sharing your tip about using an envelope follower for full wave rectification.

i just got around to fooling around with this today.

it does indeed work in mod2. although, listening to it with a saw oscillator being fed through sounds a bit duller than defex's method.

looking at it in a waveform editor, the rectified wave as from the envelope follower has a little smaller downward dip where the two halves meet, compared to defex's method.

initially i thought full wave rectification was just the waveform squished into the top halve. in that it looked like the norml wave, but only resided in the top half. so when first seeing what defex's and the envelope follower were doing visually, i knew something was askew.

anyhow...after doing some research i figured out my assumption was wrong.

now i'm good to go.

btw, full wave rectification does sound nice on a waveform. just by itself.

thanks all!

try using sine wave to see what is going on