[LAU] Sharing of Ardour projects

Jörn Nettingsmeier nettings at folkwang-hochschule.de
Thu Jun 2 16:33:15 UTC 2011


On 06/01/2011 04:29 PM, Fons Adriaensen wrote:
> On Mon, May 30, 2011 at 10:28:14AM +0200, Jörn Nettingsmeier wrote:
>> On 05/28/2011 01:37 AM, Jörn Nettingsmeier wrote:
>>> On 05/27/2011 10:08 PM, Fons Adriaensen wrote:
>>
>>>> I've got a strange problem with MFV. *Something* is poisoning
>>>> the signal graph with Nans or Infs. One visible result is that
>>>> e.g. the W channel of one of the jkmeters shows only peaks and
>>>> no RMS values (this is to be expected if the filter state gets
>>>> a Nan - once a Nan always a Nan). The other indication is that
>>>> adding an Ambdec produces a never ending xrun storm even if the
>>>> effective CPU load remains below 10%.
>>>>
>>>> Have you seen anything similar ?
>>>
>>> not in this session. sc4 can be funny at times, but i haven't had any
>>> issues with it for quite a while. i don't have access to the session
>>> atm, will ake a look when i return home on sunday. meanwhile, if you
>>> want to pinpoint the problem, try muting all channels and then unmute
>>> one by one.
>>>
>>> do the nans crop up immediately, or only after playing some audio?
>>
>> i just tested the session again, and i don't see any NaNs or INFs. what
>> i did notice, though, is that i'm burning a ridiculous amount of cpu for
>> this tiny little arrangement - i had tried with 64 frames initially, and
>> it maxes out immediately (on an 2.6 ghz i5 quad-core). safe way to run
>> it is at -p 1024 -n2.
>
> Turned out to be jconvolver. Added some Nan testing code to zita-convolver
> and the problem disappeared, also without the extra code. Could be I
> accidentally installed a version compiled on another machine. But then
> it's a miracle non of this showed up earlier...

funny. never seen that.

> Nice recording BTW. The flugelhorn solo triggered happy memories of
> recording the BRTN jazz orchestra - we had an marvellous trumpet /
> flugerhorn player then, Bert Joris<http://www.bertjoris.be/>.

thanks. yeah, flügelhorn is really like a hello kitty pillowcase for the 
soul ;-P
it's to the trumpet what the double-bass is to the electric bass guitar 
- the restrained, subtle version. you can't noodle around easily, you 
have to mean it (says an electric bass player).


cheers,


jörn



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