[Jamin] Re: [linux-audio-user] repost: curious about jamin feedback

[Jan Depner]

On Tue, 2005-03-29 at 12:32, R Parker wrote:
> > > >     Wait now, you're the one that thought it
> > would
> > > > be a good idea to add
> > > > meterbridge to JAMin.
> > > 
> > > Really? I have no recollection of suggesting that
> > and
> > > if I did am clueless as to the context within
> > which I
> > > would have cast that vote.
> > > 
> > 
> >    Someone said that they were using meterbridge and
> > another app to
> > monitor inputs to JAMin and they thought it would be
> > a good thing if
> > they were included in JAMin.  You replied that you
> > agreed.  I don't
> > remember what list it was on but I'm sure I could
> > find it.  I think it
> > might have been Joern's first post on the DC offset
> > problem.
> 
> I see no use for meterbridge in JAMin. We've already
> got good metering.
> 

    Agreed.  Plus, you can always put meterbridge in the chain (Steve's
suggestion).  The other problem is just screen real estate.  We're
trying to keep it as small as possible.  As it is I'm probably going
dual screen in the near future.

> > > Besides all that, what does meterbridge have to do
> > > with my reply?
> > > 
> > 
> >     You were complaining about too many things being
> > included in JAMin. 
> > I was just pointing out that you also want more
> > things in JAMin.
> 
> I am not the originator of the request. Joern relayed
> his experience and suggested a solution for detecting
> problems. Because it doesn't affect audio processing 
> it is an easier feature to be in favor of. In
> comparison your proposals for low, mid and high delays
> are much more complicated. And I imagine you're tired
> of arguing about it.
> 

    It's certainly not as easy to implement as the delays.  Also, there
is no reason for a delay on the high band.



> I'm curious about the results you're getting by
> routing through the BBE. Can you adjust the delay
> amount realtime and if yes could you create an example
> where you slowly sweep from no delay to the right
> amount of delay and then beyound where there's to much
> delay? If that's reasonable sweep slowly enough and
> hold in each setting long enough to adust our hearing
> and try to analyze what's happening.

    Unfortunately, no.  You can't adjust the delay times.  They are
static at ~2.5 ms for 20-150Hz and about .5 ms for 150-1200Hz.  What
you're suggesting is exactly what I'd like to try, I just don't have
anything that will do it.

> 
> How many milliseconds of delay do you suspect are
> inherent in our processing chain?
> 

     I believe there is a minimum of 10ms (the lowest limiter setting),
beyond that I'm not sure.  It shouldn't be much.

> Are you suggesting the latency is inherent in software
> or not until it hits audio card hardware?
> 

    It's in the lookahead limiter I think.

> I am accutely aware of the negative affect that timing
> and sync have and how phasing undermines amplitude
> response.
> 
> If "delay" is a real problem in mastering do you have
> any thoughts on how it's affects Ardour? It seems to
> me that there can't be any difference between it and
> JAMin. In fact phasing should be more apparent in
> Ardour simply because of the track counts. Right or
> wrong?
> 

    The delay only happens when you go to the speakers.  Some systems
now take that into account.  Heck, even my television uses a BBE
processor now ;-)


Jan