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karplus strong mathematics and the A-188-1

karplus strong mathematics and the A-188-1

2008-04-30 by Doug

Hi folks, according to my calculations, the number of BBD stages is
related to the highest possible musical note via karplus strong
synthesis as follows:

128max=G5
256max=G4
512max=G3
1024max=G2
2048max=G1
4096max=G0

Am I wrong? Here's how I got there:

1) the frequency of the karplus strong loop is the note that will be
heard as the loop attenuates. This frequency F is equal to 
F = Fs/N where Fs is the sampling rate and N is the number of samples. 

2) According to the Doepfer documentation for the A-188-1, the design
clock range of these modules is roughly 10kHz to 100kHz. I am assuming
this is the range of acceptable values for Fs. So taking Fs as 100kHz,
and N=128 (for the 128 stage BBD), the highest note that this setup
can play is 
100000Hz/128 = 781Hz or roughly a G5. The lowest note is not so much
an issue, but just for grins, 10000Hz/128= 78Hz, or roughly D#2.

3) For comparison, the 256 stage BBD will only manage 100000/256 =
390Hz, or about a G4. And it goes down an octave with each doubling of
the number of stages.

Since it appears that my guitar roughly covers octaves 1 through 4 (I
think) the 256 BBD is the ideal number of stages for plucked string
sounds.

Any advice is appreciated, especially from those who have tried BBD
modules. Thanks, Doug

Re: [Doepfer_a100] karplus strong mathematics and the A-188-1

2008-05-21 by Michael Wagner

Hi Doug,

Definitely a late reply, sorry for that.
I just received my 256-stage-BBD today,
and couldn't yet test it, but I just tried to
verify your claims. In theory, you've got the
math right, but the manual of the BBD states
the following:

"[the clock oscillator frequency] depends upon the BBD
used in the module and is related to the max. clock
frequency of the BBD in question (pls. refer to the table on
page 3). It is about 250 kHz for BBDs with 2048 and 4096
stages and about 450kHz for BBDs with 1024 stages and
less (i.e. a bit more than the max. clock frequency of the
specs in the data sheet)."

Furthermore, there is a table with the shortest available
delay for each BBD. E.g. the 256-stage BBD would have,
acording to its specification, 0.64ms minimum delay time,
which translates to 1562.5 Hz, that is roughly a G6.

So, I hope that helps a bit; and also hope I got the details
right.

-Michael
Show quoted textHide quoted text
On Wed, Apr 30, 2008 at 6:01 AM, Doug <dougc356@yahoo.com> wrote:
> Hi folks, according to my calculations, the number of BBD stages is
> related to the highest possible musical note via karplus strong
> synthesis as follows:
>
> 128max=G5
> 256max=G4
> 512max=G3
> 1024max=G2
> 2048max=G1
> 4096max=G0
>
> Am I wrong? Here's how I got there:
>
> 1) the frequency of the karplus strong loop is the note that will be
> heard as the loop attenuates. This frequency F is equal to
> F = Fs/N where Fs is the sampling rate and N is the number of samples.
>
> 2) According to the Doepfer documentation for the A-188-1, the design
> clock range of these modules is roughly 10kHz to 100kHz. I am assuming
> this is the range of acceptable values for Fs. So taking Fs as 100kHz,
> and N=128 (for the 128 stage BBD), the highest note that this setup
> can play is
> 100000Hz/128 = 781Hz or roughly a G5. The lowest note is not so much
> an issue, but just for grins, 10000Hz/128= 78Hz, or roughly D#2.
>
> 3) For comparison, the 256 stage BBD will only manage 100000/256 =
> 390Hz, or about a G4. And it goes down an octave with each doubling of
> the number of stages.
>
> Since it appears that my guitar roughly covers octaves 1 through 4 (I
> think) the 256 BBD is the ideal number of stages for plucked string
> sounds.
>
> Any advice is appreciated, especially from those who have tried BBD
> modules. Thanks, Doug

Re: karplus strong mathematics and the A-188-1

2008-05-21 by Doug

Thanks Michael, yes, I was taking 100kHz as the max internal clock 
frequency. Doubling that gives higher octaves. Thanks for your reply 
and hopefully you can report back on your 256. I have decided on the 
512 pending further input.

Thanks,
Doug

--- In Doepfer_a100@yahoogroups.com, "Michael Wagner" 
<michael.wgnr@...> wrote:
>
> Hi Doug,
> 
> Definitely a late reply, sorry for that.
> I just received my 256-stage-BBD today,
> and couldn't yet test it, but I just tried to
> verify your claims. In theory, you've got the
> math right, but the manual of the BBD states
> the following:
> 
> "[the clock oscillator frequency] depends upon the BBD
> used in the module and is related to the max. clock
> frequency of the BBD in question (pls. refer to the table on
> page 3). It is about 250 kHz for BBDs with 2048 and 4096
> stages and about 450kHz for BBDs with 1024 stages and
> less (i.e. a bit more than the max. clock frequency of the
> specs in the data sheet)."
> 
> Furthermore, there is a table with the shortest available
> delay for each BBD. E.g. the 256-stage BBD would have,
> acording to its specification, 0.64ms minimum delay time,
> which translates to 1562.5 Hz, that is roughly a G6.
> 
> So, I hope that helps a bit; and also hope I got the details
> right.
> 
> -Michael
> 
> On Wed, Apr 30, 2008 at 6:01 AM, Doug <dougc356@...> wrote:
> > Hi folks, according to my calculations, the number of BBD stages 
is
> > related to the highest possible musical note via karplus strong
> > synthesis as follows:
> >
> > 128max=G5
> > 256max=G4
> > 512max=G3
> > 1024max=G2
> > 2048max=G1
> > 4096max=G0
> >
> > Am I wrong? Here's how I got there:
> >
> > 1) the frequency of the karplus strong loop is the note that 
will be
> > heard as the loop attenuates. This frequency F is equal to
> > F = Fs/N where Fs is the sampling rate and N is the number of 
samples.
> >
> > 2) According to the Doepfer documentation for the A-188-1, the 
design
> > clock range of these modules is roughly 10kHz to 100kHz. I am 
assuming
> > this is the range of acceptable values for Fs. So taking Fs as 
100kHz,
> > and N=128 (for the 128 stage BBD), the highest note that this 
setup
> > can play is
> > 100000Hz/128 = 781Hz or roughly a G5. The lowest note is not so 
much
> > an issue, but just for grins, 10000Hz/128= 78Hz, or roughly D#2.
> >
> > 3) For comparison, the 256 stage BBD will only manage 100000/256 
=
> > 390Hz, or about a G4. And it goes down an octave with each 
doubling of
> > the number of stages.
> >
> > Since it appears that my guitar roughly covers octaves 1 through 
4 (I
> > think) the 256 BBD is the ideal number of stages for plucked 
string
> > sounds.
> >
> > Any advice is appreciated, especially from those who have tried 
BBD
> > modules. Thanks, Doug
>

Re: karplus strong mathematics and the A-188-1

2008-05-24 by hemi_ch

>>Any advice is appreciated, especially from those who have tried BBD<<

hi,
I'm not into maths, but i hvae 128, 256 and 512 stagers plus also a
4096stager.
a Frined has the 2048.
and i used to patch only with BBDs during 16 months or so, sometime back.

Overall the most interesting for me are the 256 and 512.
the 128 stager can be modulated more precise,
but for my Ears the sound is to thin.
But i must admit that i have not used it so much.

the 256stager seems overall the most interesting for me,
when counting everything together.
For Resonator Sounds the 512stager is the nicest for my Ears.

It is more belly and delivers wonderful fat tones.
the 256stager is allready thinner.

i can do also with the 496stager Resonator sounds when boosting the
Feedbackpath btw.

In general i have a 256stager and a 512stager patched together to a mixer.
and to be honest: also a third BBD.
I replaced there the 128stager with my second 256stager.
Btw.: i have patched once with three BBDs the nicest Bells i ever heard.

My recommandation would be:
take a 256 AND a 512 !
you can patch funny things with both together ;)
Biiiig experimeting Field ! loads of fun !

H.






--- In Doepfer_a100@yahoogroups.com, "Michael Wagner"
<michael.wgnr@...> wrote:
Show quoted textHide quoted text
>
> Hi Doug,
> 
> Definitely a late reply, sorry for that.
> I just received my 256-stage-BBD today,
> and couldn't yet test it, but I just tried to
> verify your claims. In theory, you've got the
> math right, but the manual of the BBD states
> the following:
> 
> "[the clock oscillator frequency] depends upon the BBD
> used in the module and is related to the max. clock
> frequency of the BBD in question (pls. refer to the table on
> page 3). It is about 250 kHz for BBDs with 2048 and 4096
> stages and about 450kHz for BBDs with 1024 stages and
> less (i.e. a bit more than the max. clock frequency of the
> specs in the data sheet)."
> 
> Furthermore, there is a table with the shortest available
> delay for each BBD. E.g. the 256-stage BBD would have,
> acording to its specification, 0.64ms minimum delay time,
> which translates to 1562.5 Hz, that is roughly a G6.
> 
> So, I hope that helps a bit; and also hope I got the details
> right.
> 
> -Michael
> 
> On Wed, Apr 30, 2008 at 6:01 AM, Doug <dougc356@...> wrote:
> > Hi folks, according to my calculations, the number of BBD stages is
> > related to the highest possible musical note via karplus strong
> > synthesis as follows:
> >
> > 128max=G5
> > 256max=G4
> > 512max=G3
> > 1024max=G2
> > 2048max=G1
> > 4096max=G0
> >
> > Am I wrong? Here's how I got there:
> >
> > 1) the frequency of the karplus strong loop is the note that will be
> > heard as the loop attenuates. This frequency F is equal to
> > F = Fs/N where Fs is the sampling rate and N is the number of samples.
> >
> > 2) According to the Doepfer documentation for the A-188-1, the design
> > clock range of these modules is roughly 10kHz to 100kHz. I am assuming
> > this is the range of acceptable values for Fs. So taking Fs as 100kHz,
> > and N=128 (for the 128 stage BBD), the highest note that this setup
> > can play is
> > 100000Hz/128 = 781Hz or roughly a G5. The lowest note is not so much
> > an issue, but just for grins, 10000Hz/128= 78Hz, or roughly D#2.
> >
> > 3) For comparison, the 256 stage BBD will only manage 100000/256 =
> > 390Hz, or about a G4. And it goes down an octave with each doubling of
> > the number of stages.
> >
> > Since it appears that my guitar roughly covers octaves 1 through 4 (I
> > think) the 256 BBD is the ideal number of stages for plucked string
> > sounds.
> >
> > Any advice is appreciated, especially from those who have tried BBD
> > modules. Thanks, Doug
>

Re: karplus strong mathematics and the A-188-1

2008-05-25 by Doug

Hi H, thanks for these subjective impressions. Very encouraging.
Doug


--- In Doepfer_a100@yahoogroups.com, "hemi_ch"
<modulardudeldidum1@...> wrote:
>
> >>Any advice is appreciated, especially from those who have tried BBD<<
> 
> hi,
> I'm not into maths, but i hvae 128, 256 and 512 stagers plus also a
> 4096stager.
> a Frined has the 2048.
> and i used to patch only with BBDs during 16 months or so, sometime
back.
> 
> Overall the most interesting for me are the 256 and 512.
> the 128 stager can be modulated more precise,
> but for my Ears the sound is to thin.
> But i must admit that i have not used it so much.
> 
> the 256stager seems overall the most interesting for me,
> when counting everything together.
> For Resonator Sounds the 512stager is the nicest for my Ears.
> 
> It is more belly and delivers wonderful fat tones.
> the 256stager is allready thinner.
> 
> i can do also with the 496stager Resonator sounds when boosting the
> Feedbackpath btw.
> 
> In general i have a 256stager and a 512stager patched together to a
mixer.
> and to be honest: also a third BBD.
> I replaced there the 128stager with my second 256stager.
> Btw.: i have patched once with three BBDs the nicest Bells i ever heard.
> 
> My recommandation would be:
> take a 256 AND a 512 !
> you can patch funny things with both together ;)
> Biiiig experimeting Field ! loads of fun !
> 
> H.
> 
> 
> 
> 
> 
> 
> --- In Doepfer_a100@yahoogroups.com, "Michael Wagner"
> <michael.wgnr@> wrote:
> >
> > Hi Doug,
> > 
> > Definitely a late reply, sorry for that.
> > I just received my 256-stage-BBD today,
> > and couldn't yet test it, but I just tried to
> > verify your claims. In theory, you've got the
> > math right, but the manual of the BBD states
> > the following:
> > 
> > "[the clock oscillator frequency] depends upon the BBD
> > used in the module and is related to the max. clock
> > frequency of the BBD in question (pls. refer to the table on
> > page 3). It is about 250 kHz for BBDs with 2048 and 4096
> > stages and about 450kHz for BBDs with 1024 stages and
> > less (i.e. a bit more than the max. clock frequency of the
> > specs in the data sheet)."
> > 
> > Furthermore, there is a table with the shortest available
> > delay for each BBD. E.g. the 256-stage BBD would have,
> > acording to its specification, 0.64ms minimum delay time,
> > which translates to 1562.5 Hz, that is roughly a G6.
> > 
> > So, I hope that helps a bit; and also hope I got the details
> > right.
> > 
> > -Michael
> > 
> > On Wed, Apr 30, 2008 at 6:01 AM, Doug <dougc356@> wrote:
> > > Hi folks, according to my calculations, the number of BBD stages is
> > > related to the highest possible musical note via karplus strong
> > > synthesis as follows:
> > >
> > > 128max=G5
> > > 256max=G4
> > > 512max=G3
> > > 1024max=G2
> > > 2048max=G1
> > > 4096max=G0
> > >
> > > Am I wrong? Here's how I got there:
> > >
> > > 1) the frequency of the karplus strong loop is the note that will be
> > > heard as the loop attenuates. This frequency F is equal to
> > > F = Fs/N where Fs is the sampling rate and N is the number of
samples.
> > >
> > > 2) According to the Doepfer documentation for the A-188-1, the
design
> > > clock range of these modules is roughly 10kHz to 100kHz. I am
assuming
> > > this is the range of acceptable values for Fs. So taking Fs as
100kHz,
> > > and N=128 (for the 128 stage BBD), the highest note that this setup
> > > can play is
> > > 100000Hz/128 = 781Hz or roughly a G5. The lowest note is not so much
> > > an issue, but just for grins, 10000Hz/128= 78Hz, or roughly D#2.
> > >
> > > 3) For comparison, the 256 stage BBD will only manage 100000/256 =
> > > 390Hz, or about a G4. And it goes down an octave with each
doubling of
> > > the number of stages.
> > >
> > > Since it appears that my guitar roughly covers octaves 1 through
4 (I
Show quoted textHide quoted text
> > > think) the 256 BBD is the ideal number of stages for plucked string
> > > sounds.
> > >
> > > Any advice is appreciated, especially from those who have tried BBD
> > > modules. Thanks, Doug
> >
>

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