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[Csnd] Quick question re realtime audio processing

Date2010-02-08 07:31
FromJK
Subject[Csnd] Quick question re realtime audio processing
Hello everyone,

I want to use csound to do real-time guitar signal processing.
My initial attempt, an instrument that simply copies audio input
to output, produced very disappointing results: the signal is
delayed by 100 to 300 ms. The .csd is simply:

   
   
   
   
     sr=44100
     kr=4410
     ksmps=10
     nchnls=1
     instr 101
     asig inch 0
          out asig
     endin
   
   
     i 101 0.0 120.0
   
   

Csound is invoked as:

   csound -iadc -odac test.csd

I've tried the advice in the Csound manual about optimizing
ksmps, -b, and -B values. I've tried many combinations of
these with no obvious effect on the results, except that when
I reduce ksmps to 0, I no longer hear any output at all (this
perplexes me). I've also searched this list for realtime
performance advice, which seems mainly to amount to "Make
buffers as small as practical".  Even with -b1, I get a
very noticeable delay.

I would like to know whether there are any obvious red flags
with my overall configuration:

   Platform:  3.0GHz Phenom II, 8GB RAM, using onboard sound
   hardware which is something NVidia-based, I believe; the
   MB is an Asus M3N78-PRO.

   Csound is a 64-bit build with double samples.

   OS is Ubuntu 9.10 desktop, with ALSA.

I have not found any blindingly obvious piece of documentation
that has helped me resolve this.  If one exists, a pointer to it
would be greatly appreciated.

Thank you,

-- JoeK

Date2010-02-08 14:05
FromAndres Cabrera
Subject[Csnd] Re: Quick question re realtime audio processing
Hi,

Are you sure you're not going through pulseaudio from alsa? This might
be the source of such a long delay.

(if the pulseaudio daemon is running it is probably the default alsa
device, and the cause of your delays)

Cheers,
Andrés

On Mon, Feb 8, 2010 at 7:31 AM, JK  wrote:
> Hello everyone,
>
> I want to use csound to do real-time guitar signal processing.
> My initial attempt, an instrument that simply copies audio input
> to output, produced very disappointing results: the signal is
> delayed by 100 to 300 ms. The .csd is simply:
>
>  
>  
>  
>  
>    sr=44100
>    kr=4410
>    ksmps=10
>    nchnls=1
>    instr 101
>    asig inch 0
>         out asig
>    endin
>  
>  
>    i 101 0.0 120.0
>  
>  
>
> Csound is invoked as:
>
>  csound -iadc -odac test.csd
>
> I've tried the advice in the Csound manual about optimizing
> ksmps, -b, and -B values. I've tried many combinations of
> these with no obvious effect on the results, except that when
> I reduce ksmps to 0, I no longer hear any output at all (this
> perplexes me). I've also searched this list for realtime
> performance advice, which seems mainly to amount to "Make
> buffers as small as practical".  Even with -b1, I get a
> very noticeable delay.
>
> I would like to know whether there are any obvious red flags
> with my overall configuration:
>
>  Platform:  3.0GHz Phenom II, 8GB RAM, using onboard sound
>  hardware which is something NVidia-based, I believe; the
>  MB is an Asus M3N78-PRO.
>
>  Csound is a 64-bit build with double samples.
>
>  OS is Ubuntu 9.10 desktop, with ALSA.
>
> I have not found any blindingly obvious piece of documentation
> that has helped me resolve this.  If one exists, a pointer to it
> would be greatly appreciated.
>
> Thank you,
>
> -- JoeK
>
>
> --
> We Americans are a freedom-loving people, and nothing says "freedom"
> like Getting Away With It. -- Guy Forsyth, "Long Long Time"
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
> csound"
>



-- 


Andrés


Send bugs reports to this list.
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Date2010-02-08 14:49
Fromandy fillebrown
Subject[Csnd] Re: Re: Quick question re realtime audio processing
Maybe try the 32 bit version of Csound, too.




On Mon, Feb 8, 2010 at 9:05 AM, Andres Cabrera  wrote:
> Hi,
>
> Are you sure you're not going through pulseaudio from alsa? This might
> be the source of such a long delay.
>
> (if the pulseaudio daemon is running it is probably the default alsa
> device, and the cause of your delays)
>
> Cheers,
> Andrés
>
> On Mon, Feb 8, 2010 at 7:31 AM, JK  wrote:
>> Hello everyone,
>>
>> I want to use csound to do real-time guitar signal processing.
>> My initial attempt, an instrument that simply copies audio input
>> to output, produced very disappointing results: the signal is
>> delayed by 100 to 300 ms. The .csd is simply:
>>
>>  
>>  
>>  
>>  
>>    sr=44100
>>    kr=4410
>>    ksmps=10
>>    nchnls=1
>>    instr 101
>>    asig inch 0
>>         out asig
>>    endin
>>  
>>  
>>    i 101 0.0 120.0
>>  
>>  
>>
>> Csound is invoked as:
>>
>>  csound -iadc -odac test.csd
>>
>> I've tried the advice in the Csound manual about optimizing
>> ksmps, -b, and -B values. I've tried many combinations of
>> these with no obvious effect on the results, except that when
>> I reduce ksmps to 0, I no longer hear any output at all (this
>> perplexes me). I've also searched this list for realtime
>> performance advice, which seems mainly to amount to "Make
>> buffers as small as practical".  Even with -b1, I get a
>> very noticeable delay.
>>
>> I would like to know whether there are any obvious red flags
>> with my overall configuration:
>>
>>  Platform:  3.0GHz Phenom II, 8GB RAM, using onboard sound
>>  hardware which is something NVidia-based, I believe; the
>>  MB is an Asus M3N78-PRO.
>>
>>  Csound is a 64-bit build with double samples.
>>
>>  OS is Ubuntu 9.10 desktop, with ALSA.
>>
>> I have not found any blindingly obvious piece of documentation
>> that has helped me resolve this.  If one exists, a pointer to it
>> would be greatly appreciated.
>>
>> Thank you,
>>
>> -- JoeK
>>
>>
>> --
>> We Americans are a freedom-loving people, and nothing says "freedom"
>> like Getting Away With It. -- Guy Forsyth, "Long Long Time"
>>
>>
>> Send bugs reports to this list.
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>> csound"
>>
>
>
>
> --
>
>
> Andrés
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"


Send bugs reports to this list.
To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"

Date2010-02-08 15:01
FromJK
Subject[Csnd] Re: Re: Re: Quick question re realtime audio processing
Thanks, andy and Andres.

I'll check out PulseAudio definitely... have read many stories
of problems with it in other contexts.  I'm not even sure
what it's for; the proliferation of "helpful" sound frameworks
in the Linux world confuses me.

BTW I wanted to correct something in my previous post:

When I reduce ksmps to *1* I no longer hear any output. This
perplexes me.  With ksmps set to any value 2...10 I get the
same results (about a 250ms delay), but when the audio and
control rate are equal, nothing.

-- JoeK

On 2/8/2010 7:49 AM, andy fillebrown wrote:
> Maybe try the 32 bit version of Csound, too.
>
>
>
>
> On Mon, Feb 8, 2010 at 9:05 AM, Andres Cabrera  wrote:
>> Hi,
>>
>> Are you sure you're not going through pulseaudio from alsa? This might
>> be the source of such a long delay.
>>
>> (if the pulseaudio daemon is running it is probably the default alsa
>> device, and the cause of your delays)
>>
>> Cheers,
>> Andrés
>>
>> On Mon, Feb 8, 2010 at 7:31 AM, JK  wrote:
>>> Hello everyone,
>>>
>>> I want to use csound to do real-time guitar signal processing.
>>> My initial attempt, an instrument that simply copies audio input
>>> to output, produced very disappointing results: the signal is
>>> delayed by 100 to 300 ms. The .csd is simply:
>>>
>>>   
>>>   
>>>   
>>>   
>>>     sr=44100
>>>     kr=4410
>>>     ksmps=10
>>>     nchnls=1
>>>     instr 101
>>>     asig inch 0
>>>          out asig
>>>     endin
>>>   
>>>   
>>>     i 101 0.0 120.0
>>>   
>>>   
>>>
>>> Csound is invoked as:
>>>
>>>   csound -iadc -odac test.csd
>>>
>>> I've tried the advice in the Csound manual about optimizing
>>> ksmps, -b, and -B values. I've tried many combinations of
>>> these with no obvious effect on the results, except that when
>>> I reduce ksmps to 0, I no longer hear any output at all (this
>>> perplexes me). I've also searched this list for realtime
>>> performance advice, which seems mainly to amount to "Make
>>> buffers as small as practical".  Even with -b1, I get a
>>> very noticeable delay.
>>>
>>> I would like to know whether there are any obvious red flags
>>> with my overall configuration:
>>>
>>>   Platform:  3.0GHz Phenom II, 8GB RAM, using onboard sound
>>>   hardware which is something NVidia-based, I believe; the
>>>   MB is an Asus M3N78-PRO.
>>>
>>>   Csound is a 64-bit build with double samples.
>>>
>>>   OS is Ubuntu 9.10 desktop, with ALSA.
>>>
>>> I have not found any blindingly obvious piece of documentation
>>> that has helped me resolve this.  If one exists, a pointer to it
>>> would be greatly appreciated.
>>>
>>> Thank you,
>>>
>>> -- JoeK
>>>
>>>
>>> --
>>> We Americans are a freedom-loving people, and nothing says "freedom"
>>> like Getting Away With It. -- Guy Forsyth, "Long Long Time"
>>>
>>>
>>> Send bugs reports to this list.
>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>> csound"
>>>
>>
>>
>>
>> --
>>
>>
>> Andrés
>>
>>
>> Send bugs reports to this list.
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"
>

Date2010-02-08 15:07
Fromjpff@cs.bath.ac.uk
Subject[Csnd] Re: Re: Re: Re: Quick question re realtime audio processing
> When I reduce ksmps to *1* I no longer hear any output. This
> perplexes me.

Any me!  Sounds like a bug.  If you chgangfe inch in in does it still get
it wrong?
==JOhn ff



Send bugs reports to this list.
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Date2010-02-08 15:09
FromAndres Cabrera
Subject[Csnd] Re: Re: Re: Re: Quick question re realtime audio processing
Hi,

I think Pulseaudio is good but not there yet for professional audio
(at least in the latest Ubuntu distribution). You need to kill it
before using jack. Apparently in the future, when jack starts,
pulseaudio will become a jack client, which would be a phenomenal
behavior, but that's not working yet...

However for standard offline processing pulseaudio works just fine,
and will allow several instances of csound to run simultaneously,
which alsa or portaudio won't do...

Cheers,
Andrés

On Mon, Feb 8, 2010 at 3:01 PM, JK  wrote:
> Thanks, andy and Andres.
>
> I'll check out PulseAudio definitely... have read many stories
> of problems with it in other contexts.  I'm not even sure
> what it's for; the proliferation of "helpful" sound frameworks
> in the Linux world confuses me.
>
> BTW I wanted to correct something in my previous post:
>
> When I reduce ksmps to *1* I no longer hear any output. This
> perplexes me.  With ksmps set to any value 2...10 I get the
> same results (about a 250ms delay), but when the audio and
> control rate are equal, nothing.
>
> -- JoeK
>
> On 2/8/2010 7:49 AM, andy fillebrown wrote:
>>
>> Maybe try the 32 bit version of Csound, too.
>>
>>
>>
>>
>> On Mon, Feb 8, 2010 at 9:05 AM, Andres Cabrera
>>  wrote:
>>>
>>> Hi,
>>>
>>> Are you sure you're not going through pulseaudio from alsa? This might
>>> be the source of such a long delay.
>>>
>>> (if the pulseaudio daemon is running it is probably the default alsa
>>> device, and the cause of your delays)
>>>
>>> Cheers,
>>> Andrés
>>>
>>> On Mon, Feb 8, 2010 at 7:31 AM, JK  wrote:
>>>>
>>>> Hello everyone,
>>>>
>>>> I want to use csound to do real-time guitar signal processing.
>>>> My initial attempt, an instrument that simply copies audio input
>>>> to output, produced very disappointing results: the signal is
>>>> delayed by 100 to 300 ms. The .csd is simply:
>>>>
>>>>  
>>>>  
>>>>  
>>>>  
>>>>    sr=44100
>>>>    kr=4410
>>>>    ksmps=10
>>>>    nchnls=1
>>>>    instr 101
>>>>    asig inch 0
>>>>         out asig
>>>>    endin
>>>>  
>>>>  
>>>>    i 101 0.0 120.0
>>>>  
>>>>  
>>>>
>>>> Csound is invoked as:
>>>>
>>>>  csound -iadc -odac test.csd
>>>>
>>>> I've tried the advice in the Csound manual about optimizing
>>>> ksmps, -b, and -B values. I've tried many combinations of
>>>> these with no obvious effect on the results, except that when
>>>> I reduce ksmps to 0, I no longer hear any output at all (this
>>>> perplexes me). I've also searched this list for realtime
>>>> performance advice, which seems mainly to amount to "Make
>>>> buffers as small as practical".  Even with -b1, I get a
>>>> very noticeable delay.
>>>>
>>>> I would like to know whether there are any obvious red flags
>>>> with my overall configuration:
>>>>
>>>>  Platform:  3.0GHz Phenom II, 8GB RAM, using onboard sound
>>>>  hardware which is something NVidia-based, I believe; the
>>>>  MB is an Asus M3N78-PRO.
>>>>
>>>>  Csound is a 64-bit build with double samples.
>>>>
>>>>  OS is Ubuntu 9.10 desktop, with ALSA.
>>>>
>>>> I have not found any blindingly obvious piece of documentation
>>>> that has helped me resolve this.  If one exists, a pointer to it
>>>> would be greatly appreciated.
>>>>
>>>> Thank you,
>>>>
>>>> -- JoeK
>>>>
>>>>
>>>> --
>>>> We Americans are a freedom-loving people, and nothing says "freedom"
>>>> like Getting Away With It. -- Guy Forsyth, "Long Long Time"
>>>>
>>>>
>>>> Send bugs reports to this list.
>>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>>> csound"
>>>>
>>>
>>>
>>>
>>> --
>>>
>>>
>>> Andrés
>>>
>>>
>>> Send bugs reports to this list.
>>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>>> csound"
>>
>>
>> Send bugs reports to this list.
>> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
>> csound"
>>
>
>
> --
> We Americans are a freedom-loving people, and nothing says "freedom"
> like Getting Away With It. -- Guy Forsyth, "Long Long Time"
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
> csound"
>



-- 


Andrés


Send bugs reports to this list.
To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"

Date2010-02-10 18:27
FromJK
Subject[Csnd] Re: Quick question re realtime audio processing
OK, let me ask another question:

What packages should I have installed on an Ubuntu system for
real-time Csound to work?

After un-installing PulseAudio, Csound can no longer read or
write any audio data :-(  It seems to hang after compiling
the orchestra, although it does not issue any error messages.

Thanks,

-- JoeK (wondering: whatever happened to reading from /dev/dsp
and writing to /dev/audio?  Which also doesn't seem to work,
incidentally)


On 2/8/2010 12:31 AM, JK wrote:
> Hello everyone,
>
> I want to use csound to do real-time guitar signal processing.
> My initial attempt, an instrument that simply copies audio input
> to output, produced very disappointing results: the signal is
> delayed by 100 to 300 ms. The .csd is simply:
>
> 
> 
> 
> 
> sr=44100
> kr=4410
> ksmps=10
> nchnls=1
> instr 101
> asig inch 0
> out asig
> endin
> 
> 
> i 101 0.0 120.0
> 
> 
>
> Csound is invoked as:
>
> csound -iadc -odac test.csd
>
> I've tried the advice in the Csound manual about optimizing
> ksmps, -b, and -B values. I've tried many combinations of
> these with no obvious effect on the results, except that when
> I reduce ksmps to 0, I no longer hear any output at all (this
> perplexes me). I've also searched this list for realtime
> performance advice, which seems mainly to amount to "Make
> buffers as small as practical". Even with -b1, I get a
> very noticeable delay.
>
> I would like to know whether there are any obvious red flags
> with my overall configuration:
>
> Platform: 3.0GHz Phenom II, 8GB RAM, using onboard sound
> hardware which is something NVidia-based, I believe; the
> MB is an Asus M3N78-PRO.
>
> Csound is a 64-bit build with double samples.
>
> OS is Ubuntu 9.10 desktop, with ALSA.
>
> I have not found any blindingly obvious piece of documentation
> that has helped me resolve this. If one exists, a pointer to it
> would be greatly appreciated.
>
> Thank you,
>
> -- JoeK
>
>

Date2010-02-10 18:37
FromAndres Cabrera
Subject[Csnd] Re: Re: Quick question re realtime audio processing
Hi,

There's no need to completely uninstall Pulseaudio. You just need to
remember to kill it before doing audio work. Maybe you need to select
a different realtime audio module (portaudio/alsa/jack).

Cheers,
Andrés

On Wed, Feb 10, 2010 at 6:27 PM, JK  wrote:
> OK, let me ask another question:
>
> What packages should I have installed on an Ubuntu system for
> real-time Csound to work?
>
> After un-installing PulseAudio, Csound can no longer read or
> write any audio data :-(  It seems to hang after compiling
> the orchestra, although it does not issue any error messages.
>
> Thanks,
>
> -- JoeK (wondering: whatever happened to reading from /dev/dsp
> and writing to /dev/audio?  Which also doesn't seem to work,
> incidentally)
>
>
> On 2/8/2010 12:31 AM, JK wrote:
>>
>> Hello everyone,
>>
>> I want to use csound to do real-time guitar signal processing.
>> My initial attempt, an instrument that simply copies audio input
>> to output, produced very disappointing results: the signal is
>> delayed by 100 to 300 ms. The .csd is simply:
>>
>> 
>> 
>> 
>> 
>> sr=44100
>> kr=4410
>> ksmps=10
>> nchnls=1
>> instr 101
>> asig inch 0
>> out asig
>> endin
>> 
>> 
>> i 101 0.0 120.0
>> 
>> 
>>
>> Csound is invoked as:
>>
>> csound -iadc -odac test.csd
>>
>> I've tried the advice in the Csound manual about optimizing
>> ksmps, -b, and -B values. I've tried many combinations of
>> these with no obvious effect on the results, except that when
>> I reduce ksmps to 0, I no longer hear any output at all (this
>> perplexes me). I've also searched this list for realtime
>> performance advice, which seems mainly to amount to "Make
>> buffers as small as practical". Even with -b1, I get a
>> very noticeable delay.
>>
>> I would like to know whether there are any obvious red flags
>> with my overall configuration:
>>
>> Platform: 3.0GHz Phenom II, 8GB RAM, using onboard sound
>> hardware which is something NVidia-based, I believe; the
>> MB is an Asus M3N78-PRO.
>>
>> Csound is a 64-bit build with double samples.
>>
>> OS is Ubuntu 9.10 desktop, with ALSA.
>>
>> I have not found any blindingly obvious piece of documentation
>> that has helped me resolve this. If one exists, a pointer to it
>> would be greatly appreciated.
>>
>> Thank you,
>>
>> -- JoeK
>>
>>
>
>
> --
> We Americans are a freedom-loving people, and nothing says "freedom"
> like Getting Away With It. -- Guy Forsyth, "Long Long Time"
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe
> csound"
>



-- 


Andrés


Send bugs reports to this list.
To unsubscribe, send email sympa@lists.bath.ac.uk with body "unsubscribe csound"

Date2010-02-10 18:57
FromVictor Lazzarini
Subject[Csnd] Re: Re: Quick question re realtime audio processing
Try adding -+rtaudio=alsa to the command line.


On 10 Feb 2010, at 18:27, JK wrote:

> OK, let me ask another question:
>
> What packages should I have installed on an Ubuntu system for
> real-time Csound to work?
>
> After un-installing PulseAudio, Csound can no longer read or
> write any audio data :-(  It seems to hang after compiling
> the orchestra, although it does not issue any error messages.
>
> Thanks,
>
> -- JoeK (wondering: whatever happened to reading from /dev/dsp
> and writing to /dev/audio?  Which also doesn't seem to work,
> incidentally)
>
>
> On 2/8/2010 12:31 AM, JK wrote:
>> Hello everyone,
>>
>> I want to use csound to do real-time guitar signal processing.
>> My initial attempt, an instrument that simply copies audio input
>> to output, produced very disappointing results: the signal is
>> delayed by 100 to 300 ms. The .csd is simply:
>>
>> 
>> 
>> 
>> 
>> sr=44100
>> kr=4410
>> ksmps=10
>> nchnls=1
>> instr 101
>> asig inch 0
>> out asig
>> endin
>> 
>> 
>> i 101 0.0 120.0
>> 
>> 
>>
>> Csound is invoked as:
>>
>> csound -iadc -odac test.csd
>>
>> I've tried the advice in the Csound manual about optimizing
>> ksmps, -b, and -B values. I've tried many combinations of
>> these with no obvious effect on the results, except that when
>> I reduce ksmps to 0, I no longer hear any output at all (this
>> perplexes me). I've also searched this list for realtime
>> performance advice, which seems mainly to amount to "Make
>> buffers as small as practical". Even with -b1, I get a
>> very noticeable delay.
>>
>> I would like to know whether there are any obvious red flags
>> with my overall configuration:
>>
>> Platform: 3.0GHz Phenom II, 8GB RAM, using onboard sound
>> hardware which is something NVidia-based, I believe; the
>> MB is an Asus M3N78-PRO.
>>
>> Csound is a 64-bit build with double samples.
>>
>> OS is Ubuntu 9.10 desktop, with ALSA.
>>
>> I have not found any blindingly obvious piece of documentation
>> that has helped me resolve this. If one exists, a pointer to it
>> would be greatly appreciated.
>>
>> Thank you,
>>
>> -- JoeK
>>
>>
>
>
> --  
> We Americans are a freedom-loving people, and nothing says "freedom"
> like Getting Away With It. -- Guy Forsyth, "Long Long Time"
>
>
> Send bugs reports to this list.
> To unsubscribe, send email sympa@lists.bath.ac.uk with body  
> "unsubscribe csound"



Send bugs reports to this list.
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Date2010-02-10 19:16
FromJK
Subject[Csnd] Re: Re: Re: Quick question re realtime audio processing
Ah, OK. That worked.  I thought I'd already tried that, but
I used "-rtaudio=alsa", missing the "+" in the csound manpage.

Now it's basically working :-))  Still some nasty artifacts,
but that's just a matter of tweaking software and/or hardware,
I think.

Thanks, everyone!

-- JoeK


On 2/10/2010 11:57 AM, Victor Lazzarini wrote:
> Try adding -+rtaudio=alsa to the command line.
>
>
> On 10 Feb 2010, at 18:27, JK wrote:
>
>> OK, let me ask another question:
>>
>> What packages should I have installed on an Ubuntu system for
>> real-time Csound to work?
>>
>> After un-installing PulseAudio, Csound can no longer read or
>> write any audio data :-( It seems to hang after compiling
>> the orchestra, although it does not issue any error messages.
>>
>> Thanks,
>>
>> -- JoeK (wondering: whatever happened to reading from /dev/dsp
>> and writing to /dev/audio? Which also doesn't seem to work,
>> incidentally)
>>
>>
>> On 2/8/2010 12:31 AM, JK wrote:
>>> Hello everyone,
>>>
>>> I want to use csound to do real-time guitar signal processing.
>>> My initial attempt, an instrument that simply copies audio input
>>> to output, produced very disappointing results: the signal is
>>> delayed by 100 to 300 ms. The .csd is simply:
>>>
>>> 
>>> 
>>> 
>>> 
>>> sr=44100
>>> kr=4410
>>> ksmps=10
>>> nchnls=1
>>> instr 101
>>> asig inch 0
>>> out asig
>>> endin
>>> 
>>> 
>>> i 101 0.0 120.0
>>> 
>>> 
>>>
>>> Csound is invoked as:
>>>
>>> csound -iadc -odac test.csd
>>>
>>> I've tried the advice in the Csound manual about optimizing
>>> ksmps, -b, and -B values. I've tried many combinations of
>>> these with no obvious effect on the results, except that when
>>> I reduce ksmps to 0, I no longer hear any output at all (this
>>> perplexes me). I've also searched this list for realtime
>>> performance advice, which seems mainly to amount to "Make
>>> buffers as small as practical". Even with -b1, I get a
>>> very noticeable delay.
>>>
>>> I would like to know whether there are any obvious red flags
>>> with my overall configuration:
>>>
>>> Platform: 3.0GHz Phenom II, 8GB RAM, using onboard sound
>>> hardware which is something NVidia-based, I believe; the
>>> MB is an Asus M3N78-PRO.
>>>
>>> Csound is a 64-bit build with double samples.
>>>
>>> OS is Ubuntu 9.10 desktop, with ALSA.
>>>
>>> I have not found any blindingly obvious piece of documentation
>>> that has helped me resolve this. If one exists, a pointer to it
>>> would be greatly appreciated.
>>>
>>> Thank you,
>>>
>>> -- JoeK
>>>
>>>
>>
>>
>> -- We Americans are a freedom-loving people, and nothing says "freedom"
>> like Getting Away With It. -- Guy Forsyth, "Long Long Time"
>>
>>
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