Plumbutter CV I/O Wave/Range Analysis

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Setherian
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Plumbutter CV I/O Wave/Range Analysis

Post by Setherian » Tue Jul 01, 2014 4:09 pm

I borrowed an O'Tool from a friend and it was the best thing i could have done in terms of upgrading considerably my understanding of my Plumbutter amongst other instruments, I would like to share some knowledge about the modulation outputs mostly, details I probably would never understand if I didnt analyze the waves visually, so here it goes, a list of the basic properties of each cv output of the plumbutter and perhaps some insight on inputs and audio outs as well, we will see..

ps: if you disagree or find any incoherence, please share your knowledge.


MWTRS:

Reds = Negative pulse outputs that range between +0V and - 10V.

Oranges = Positive pulses that can eventually be gates, Range between 0 and 8V.

Gray = A "Squarable quantized voltage that relates to the noise source (so it can get pretty chaotic!), offset can vary a bit and range is bipolar, somewhere between +5v and -8V. As I tweak the the snare decay knob it seems like its inverting the wave, curious thing, pulses that were up are then down.


ROLLS:

Oranges = Positive voltage, between 0 and 5V! As a clean oscillation, it looks like a square wave with an logarithmic curvy attack.

Browns = Also pulses with a bit of an exp. decay, mostly negative down to -10V , sometimes I saw shallow positive picks up to +4V. Pulse sequences could look pretty nasty sometimes..



GONGUES:


Oranges = Positive voltage, look like gates with a slightly progressive decay, ranging between 0 and +5V. Offset seems always above 0!?

Grays = wave pulsing at the offbeat of the orange one, offset is at 0 and it does range in bipolar fashion, somewhere between -5 and +5V. The form looks more interesting as it has a exp decay with sustain and exponential release.

*An inconvenience I found about the gongues the time i did this tests is, you can trigger them by simply touching your nana cable in another cable that connects a pulse out to somewhere (the rubbers, not leads), kinda fucked up no??


AVDOGS:

Oranges = Positive Oscillation (around 0-7V) , looks like sine waves that sometimes become trapezoidal.

Reds = Audio Rate output! Looks more like triangles most of the time in my Oscilloscope, not sure it can modulate anything but FMs, or?


ULTRASOUNDS:


Yellows = Bipolar (between +-5 V) squared waves.


*Curiously it was when I did those tests that I finally found out the green jacks are not asking for pulses really (like the Gongues) , I mean, you can do it, but it always sound like a shitty spike to me, no, it actually asks for some nice audio rate wave! Finally! :)



DEERHORN:


Reds = Gate outs!!! Pretty hot signal (between +-7V), also bipolar (it kinda depends if you activate both at the same time or not and the calibration setting!)

Orange = This was a great discovery, I never could understand before analyzing the wave how to work with the theta wave, to get it to curve full range (0 to +10V) you need to have your hand very close to the board, like bouncing it within 2 cm range mostly) ( kinda tricky! )

Sure most of this info is covered in Peters page, but allowing myself to understand more how the waves look like and behave in whatever offset or range helped me a lot, hope this info helps someone else too!!


:deadbanana:


Seth
Last edited by Setherian on Tue Jul 01, 2014 6:40 pm, edited 2 times in total.

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wednesdayayay
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Post by wednesdayayay » Tue Jul 01, 2014 4:34 pm

Glad to hear your PB progress
the negative space the avdog inhabits refers to
when you ring the avdog it bounces a tone between the L and R outputs
when this sound is off the red output is on

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pugix
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Post by pugix » Tue Jul 01, 2014 5:38 pm

The Orange output from Rolls is always a positive pulse. It's DC-coupled and cannot go below ground. If you think you're seeing this, your scope isn't set right. The Brown Rolls jacks are at the base of a transistor with a capacitor going to it. These look like negative pulses, below ground, even though there is only a positive supply voltage.

In general you can expect negative outputs to be seen only on AC-coupled outputs.
Richard
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"Everything in our world is actually always modulated by everything else." - Peter B

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mrbloor
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Post by mrbloor » Tue Jul 01, 2014 5:41 pm

Thanks for the share, very interesting reading

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Setherian
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Post by Setherian » Tue Jul 01, 2014 6:03 pm

Oh shit, it is true, my analysis of the Rolls Oranges was incorrect, it is indeed solely positive, between 0 and 4,5V. and it does look like a gate but with a logarithmic rise and a squared fall! I will correct it in the original post! After a second try it seems like many of my data was incorrect, maybe a ground problem, now it seems to be more right! sorry! original post updated!

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