Delta Modulation VST? (Nintendo NES's sample channel)
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- KVRist
- Topic Starter
- 250 posts since 30 Jan, 2009
Is there any VST that converts an input into a delta modulated signal?
It's the same system that the Nintendo NES uses to play samples.
Basically it's a 1 bit stream of audio that either tells the amplitude to go up or down each cycle depending on how fast the cycles are processed.
Is there anything like this?
It's the same system that the Nintendo NES uses to play samples.
Basically it's a 1 bit stream of audio that either tells the amplitude to go up or down each cycle depending on how fast the cycles are processed.
Is there anything like this?
Last edited by clayman256 on Sat Jun 02, 2012 11:04 am, edited 1 time in total.
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- KVRian
- 653 posts since 4 Apr, 2010
Hi clayman—could you tell me why you'd like to do this? Just curious—not making any implied judgement. Do you want some slew-limiting distortion, for instance? It seems that delta-mod, in its most shining implementations, tries to be what PCM is. So, I'm assuming you want some of the negative qualities as an effect, maybe? That is, I suppose you mean to put full samples into it, and get full samples out of it, but do a delta-mod in between. Am I reading your correctly?clayman256 wrote:Is there any VST that converts an input into a delta modulated signal?
It's the same system that the Nintendo NES uses to play samples.
Basically it's a 1 bit stream of audio that either tells the amplitude to go up or down each cycle depending on how fast the cycles are processed.
Is there anything like this?
I remember Stephen St. Croix, in the 70's at AES, hawking his Marshall Time Modulator, bristling as he described the shortcoming of his digital competitor and the horrors of their delta modulation...(and I really liked the MTM back then, btw, and was fortunate to have access to one at the electronic music lab...)
My audio DSP blog: earlevel.com
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- KVRist
- Topic Starter
- 250 posts since 30 Jan, 2009
I want to record of use an input stream through something that simulates delta modulation. I want to use it as a lo-fi effect reminiscent of the NES's Delta Modulation channel.
I found this which does it with WAV files, but I'd like one for incoming inputs.
http://www.mattmontag.com/projects-page/nintendo-vst
This is basically what happens in delta modulation:
In a conversion of a signal, the delta modulated signal either rises or falls each interval, hence a 1 bit modulation of the waveform.
It's a really neat form of sampling compared to sample/bit crushing.
I found this which does it with WAV files, but I'd like one for incoming inputs.
http://www.mattmontag.com/projects-page/nintendo-vst
This is basically what happens in delta modulation:
In a conversion of a signal, the delta modulated signal either rises or falls each interval, hence a 1 bit modulation of the waveform.
It's a really neat form of sampling compared to sample/bit crushing.
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- KVRian
- 653 posts since 4 Apr, 2010
OK, that's what I was alluding to when I asked if you were after "slew [rate] limiting distortion". It wouldn't be difficult to do at all. In a quick search for "slew rate limiting vst", I came up with this as the first link:clayman256 wrote:I want to record of use an input stream through something that simulates delta modulation. I want to use it as a lo-fi effect reminiscent of the NES's Delta Modulation channel.
http://bedroomproducersblog.com/2012/01 ... st-plugin/
"Studio Machina Releases SL-500 Free Slew Rate Limiter VST Plugin"
I don't know if that will give the effect you're after, but you might try searches along those lines.
My audio DSP blog: earlevel.com
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- KVRian
- 904 posts since 3 Aug, 2001 from Montreal
David Viens, Plogue Art et Technologie Inc. Montreal.
https://twitter.com/plgDavid
https://plogue.com
https://twitter.com/plgDavid
https://plogue.com
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- KVRist
- Topic Starter
- 250 posts since 30 Jan, 2009
Thanks! This could simulate the timing of rising the waveform up and down. I could probably throw a sample rate and bit crusher after it.earlevel wrote:OK, that's what I was alluding to when I asked if you were after "slew [rate] limiting distortion". It wouldn't be difficult to do at all. In a quick search for "slew rate limiting vst", I came up with this as the first link:clayman256 wrote:I want to record of use an input stream through something that simulates delta modulation. I want to use it as a lo-fi effect reminiscent of the NES's Delta Modulation channel.
http://bedroomproducersblog.com/2012/01 ... st-plugin/
"Studio Machina Releases SL-500 Free Slew Rate Limiter VST Plugin"
I don't know if that will give the effect you're after, but you might try searches along those lines.
That would be spot on. Can't wait to see this plugin when it's released!davidv@plogue wrote:http://www.youtube.com/watch?v=te_Br2ew6Hc
- KVRAF
- 5223 posts since 20 Jul, 2010
If you have Chipsounds you can do this already, if you're willing to edit a text file (I managed it, so you probably can too). This'll also let you switch between C64-style 4-bit modulation (which is brighter and crunchier) and NES style (which is very muffled, and looks like a modulated triangle wave almost). You can only use it on pre-recorded waves in a certain folder, but the upside is it's instant authenticity if that's what you're going for.
The Shortcircuit sampler features a slew limiter as one of it's insert filters. I've found this really useful for grunging up beats and you can modulate it with LFO's, envelope followers, etc, but obviously, it can only affect stuff you've made in the sampler.
EDIT: If you have Spectralworx, I also noticed the other day it has a slew limiter, which lets you set different rates for upward and downward parts of the waveform. This can create some VERY messed up effects
The Shortcircuit sampler features a slew limiter as one of it's insert filters. I've found this really useful for grunging up beats and you can modulate it with LFO's, envelope followers, etc, but obviously, it can only affect stuff you've made in the sampler.
EDIT: If you have Spectralworx, I also noticed the other day it has a slew limiter, which lets you set different rates for upward and downward parts of the waveform. This can create some VERY messed up effects
http://sendy.bandcamp.com/releases < My new album at Bandcamp! Now pay what you like!
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- KVRAF
- 12235 posts since 18 Aug, 2003
There's this:
http://www.savioursofsoul.de/Christian/ ... SigmaDelta
Don't know if it does exactly what you want though.
http://www.savioursofsoul.de/Christian/ ... SigmaDelta
Don't know if it does exactly what you want though.
- KVRian
- 1110 posts since 31 Aug, 2001 from Los Angeles, CA
I just threw one together out of mild curiosity of how it sounded compared to traditional sr/bit-reduction.
extremely crude / very untested / at your own risk, etc.
http://www.xferrecords.com/freeware/Del ... atorPC.zip (x32 x64)
http://www.xferrecords.com/freeware/Del ... torOSX.zip (vst and au)
-Steve
extremely crude / very untested / at your own risk, etc.
http://www.xferrecords.com/freeware/Del ... atorPC.zip (x32 x64)
http://www.xferrecords.com/freeware/Del ... torOSX.zip (vst and au)
-Steve
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- KVRian
- 904 posts since 3 Aug, 2001 from Montreal
Most of the processing stuff and impulses are done. We are working on the UI and presets at this point. We hope to release it in a few months.rexlapin wrote:Hi David,
Any ETA on this? I have chipsounds and love it but this seems like a great
extension of the vibe.
Cheers,
Scott
Cheers
David Viens, Plogue Art et Technologie Inc. Montreal.
https://twitter.com/plgDavid
https://plogue.com
https://twitter.com/plgDavid
https://plogue.com
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- KVRist
- Topic Starter
- 250 posts since 30 Jan, 2009
I'll definitely be checking it out. Looks amazing.davidv@plogue wrote:Most of the processing stuff and impulses are done. We are working on the UI and presets at this point. We hope to release it in a few months.rexlapin wrote:Hi David,
Any ETA on this? I have chipsounds and love it but this seems like a great
extension of the vibe.
Cheers,
Scott
Cheers
bitcrusher wrote:I just threw one together out of mild curiosity of how it sounded compared to traditional sr/bit-reduction.
extremely crude / very untested / at your own risk, etc.
http://www.xferrecords.com/freeware/Del ... atorPC.zip (x32 x64)
http://www.xferrecords.com/freeware/Del ... torOSX.zip (vst and au)
-Steve
Wow, that plugin is really nice! It simulates the characteristics pretty nicely. I'll be using this for some stuff. I like how the slew rate is in sync with the bit depth so you can never rise of fall more than 1 quantity at a time.
There is one thing I have to mention though.
One of the things that real Delta Modulation does though, is that the fact that since it is a constant amplitude modulation from a 1 bit stream, the bit either tells it to go up or down in an interval.
This means that the waveform is constantly moving up or down.
This means even in silence the waveform is moving up and down each interval.
In short: It can never be the same amplitude twice.
Basically if it was a flat input it would dither up and down each interval if it was already near the amplitude of the input.
Notice at the end of the sample, the modulated form dithers back and forth to be as close to the amplitude signal as possible.
I am still very impressed by your plugin though, it's just that I wanted to point out that actual DM does that.
- KVRian
- 1110 posts since 31 Aug, 2001 from Los Angeles, CA
Cheers, glad you like it - I did have it act like that at first, but it would whine when input was silent, which I thought wasn't very nice, not to mention people would think it is a bug..I am still very impressed by your plugin though, it's just that I wanted to point out that actual DM does that.
I was thinking to add a switch to toggle that behavior, and maybe a second switch to gate when input is silent for a certain number of samples... shouldn't take long, I'll report back when I've done so.
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- KVRist
- Topic Starter
- 250 posts since 30 Jan, 2009
That would be amazing! But seriously, I'm really thankful for this plugin. It sounds like a really good simulation compared to when I used an real DM encoder in FamiTracker.bitcrusher wrote:Cheers, glad you like it - I did have it act like that at first, but it would whine when input was silent, which I thought wasn't very nice, not to mention people would think it is a bug..I am still very impressed by your plugin though, it's just that I wanted to point out that actual DM does that.
I was thinking to add a switch to toggle that behavior, and maybe a second switch to gate when input is silent for a certain number of samples... shouldn't take long, I'll report back when I've done so.
The reason why there's no hum in, say, NES music with DM samples is because the channel is silent when the sample is done, and most samples are cut out at the silence, for both that reason, and to save ROM data.
- KVRian
- 1110 posts since 31 Aug, 2001 from Los Angeles, CA