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synthmonger
Joined: Nov 16, 2006 Posts: 578 Location: flada
Audio files: 3
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Posted: Tue Feb 17, 2009 2:49 pm Post subject:
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Hey Tom you might wanna try using the 40106 vco I posted in the Lunetta thread as your main clock source for this circuit. Works pretty good! |
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rumpofsteelskin
Joined: Apr 22, 2009 Posts: 52 Location: brighton, uk
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Posted: Wed Jun 17, 2009 9:54 am Post subject:
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bigtex wrote: | It all starts with a sawtooth wave. This is quantized by the first S&H chip and turned from a ramp shape into a staircase shape at a rate determined by the clock.
That same original sawtooth wave is also fed into a comparator. It is compared to the audio input. Every time the comparator's state changes (caused by the sawtooth wave or audio input becoming higher or lower than the other) the second S&H samples the current step of the staircase wave. |
Has this been abandoned?? I was toying around with it but noticed two problems -
- Changing the sample rate also changes the amount of quantization levels; lower sample rate = more amplitude levels. This could be sorted by phase locking the square wave to the sawtooth wave.
- The speed of the square/pulse wave looks to be prohibitively fast. Say if you want maximum resolution at 20KHz, then a minimum of 40K sawtooth wave to sample it with, and then assuming that 14bits is the maximum fidelity bit depth, that means 2^14 = 16384 possible amplitude levels. Which means the square wave clock must be at minimum 166384x40000 = 655MHz. This must also be variable to give the lowest resolution at the lowest frequency, say 30Hz. 30x2x2 = 120Hz.
Unfortunately, this doesn't look feasible which is quite a shame, the idea of it is pretty clever.
I think probably the only way to do the amplitude quantization is digitally...
does anyone know how the frostwave sonic annihilator works?? |
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rumpofsteelskin
Joined: Apr 22, 2009 Posts: 52 Location: brighton, uk
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Posted: Wed Jun 17, 2009 11:37 am Post subject:
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*sonic alienator, rather... |
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rosch
Joined: Oct 03, 2009 Posts: 164 Location: germany
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Posted: Tue Mar 16, 2010 4:50 pm Post subject:
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hi guys!
i have built modularkomplex's LF398 based rate reducer today (from page 3 of this topic).
i have one issue here. there's a very audible cv, almost as loud as the audio signal. when i turn the pot the pitch of the noise goes all the way up/down.
the effect itself works fine on the audio signal (edit: at least seems so).
i played bass through it and could turn the rate down (1M pot) so much that it sounded detuned (edit: with the cv i guess) and got pitch modulated. but i must have made a mistake so the cv comes through...
any idea what i could have done wrong here?
thanks!
***
edit: just created a new thread here |
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nilsomat
Joined: Nov 20, 2011 Posts: 7 Location: Germany
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Posted: Mon Nov 21, 2011 2:04 am Post subject:
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Hello everybody, my first post I have been reading this forum for quite a while, a great level of expertise here, good stuff!
I have been thinking about building a bugcrusher-like-device for some time so i thought it would be a good idea to bump this thread to ask for any updates, schematics and the like. I would prefer a LF398 based device because of better availability.
Thanks a lot for any input!
Greetings,
Nils |
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bugbrand
Joined: Nov 27, 2005 Posts: 846 Location: Bristol, UK
Audio files: 1
G2 patch files: 1
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Uncle Krunkus
Moderator
Joined: Jul 11, 2005 Posts: 4761 Location: Sydney, Australia
Audio files: 52
G2 patch files: 1
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Posted: Fri Oct 24, 2014 5:47 pm Post subject:
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This is really cool Tom. _________________ What makes a space ours, is what we put there, and what we do there. |
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isak
Joined: Dec 13, 2009 Posts: 847 Location: Israel
Audio files: 18
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vladosh
Joined: Aug 02, 2010 Posts: 659 Location: macedonia
Audio files: 46
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