[AG-TECH] XAP setup - urgent

Thu Feb 17 17:32:55 CST 2005

That's a good point to start with. I'll try to test that tomorrow if I can
get someone to help me in this matters from our university partners.

I'll keep you and the list informed about the results and improvements.

Thanx a lot.

> If you are using 2 superceded mics and have 6 to 8 people talking and
> they are not all directly in front of one or the other of these
> microphones then indeed the levels will vary greatly. The pickup
> pattern is typically designed to reject audio that is out side of
> approximately 60 degrees. Some of the other reasons for your levels
> fluctuating would include having PA adapt mode off as well as first mic
> priority. With first mic priority off the two microphones you have will
> fluctuate between the different sources or might even allow one talker
> to gat them both on and cause phasing that will attenuate the signal
> and affect its' tonality. PA adapt mode help the AEC to handle the echo
> in your room, If it is disable the AEC may add suppression that will
> attenuate the level you send to other nodes. This coupled with NLP off
> and you will get either bursty echo or a loss of duplex with other
> nodes.
>
> -----Original Message-----
> From: Natalia Costas Lago [mailto:natalia at cesga.es]
> Sent: Thursday, February 17, 2005 2:40 PM
> To: tcoffin at ncsa.uiuc.edu
> Cc: natalia at cesga.es; Paul.Kuchar at manchester.ac.uk;
> ag-tech at mcs.anl.gov; vgoya at uvigo.es; raul at scom.uminho.pt;
> Amândio at cesga.es; amandio at scom.uminho.pt; mquintas at uvigo.es;
> ccaride at uvigo.es; gcastro at uvigo.es; nlopez at cesga.es; Tech Mailbox
> Subject: Re: [AG-TECH] XAP setup - urgent
>
>
>
> mmm.... that doesnt seem to be an acceptable solution for us.
>
> What I have experienced in our meetings is that we can have up to 6-8
> people talking to 2 supercardioid microphones and each of them speak at
> a different level. It is too hard (impossible) for a tech to try to
> adjust the level each time any of them speak (sometimes some of them at
> the same time :)))).
>
> I recall a sentence I read in one of those accessgrid papers... "for
> the tech to vanish...". That's what we want, the less a tech has to
> care about the better. I think the XAP should be able to do AGC
> (automatic gain control) if it is set properly. We do not have problems
> with noise level increase if there is a proper threshold set, maybe..
> do some other problems appear?.
>
> Personally, what I get out of my experience is that I rather prefer our
> system after enabling the AGC than before. But I think our settings can
> be improved, that's why I am cc'ing clearone tech staff, they are the
> ones who can tell us what we can get out of the XAP.
>
>
>
>>
>> We run into people with different speaking levels a lot during
>> meetings here at ACCESS. The way we handle it is to try and identify a
>>  microphone for the soft spoken speaker and boost the fine gain
>> control  for it using gware.
>>
>>
>> _______________________________________________
>> At 12:16 PM 2/17/2005, Natalia Costas Lago wrote:
>>>"urn:schemas-microsoft-com:vml" xmlns:o =
>>>"urn:schemas-microsoft-com:office:office" xmlns:w =
>>>"urn:schemas-microsoft-com:office:word" xmlns:st1 =
>>>"urn:schemas-microsoft-com:office:smarttags">
>>>
>>>Hi Paul,
>>>
>>>I think we do really need the AGC settings, the audio levels are
>>>uncontrolled without it. We avoid echo issues with them, maybe do you
>>>use  the Compressor feature?.
>>>
>>>There is some trouble with people that speak louder or lower. I think
>>>there has to be a right way to set it...
>>>I am CC'ing clearone tech guys, maybe they have some advice?
>>>
>>>Kind regards,
>>>Natalia.
>>>
>>>----- Original Message -----
>>>From: <mailto:Paul.Kuchar at manchester.ac.uk>Paul Kuchar
>>>To: <mailto:natalia at cesga.es>'Natalia Costas Lago'
>>>Sent: Thursday, February 17, 2005 5:54 PM
>>>Subject: RE: [AG-TECH] XAP setup - urgent
>>>
>>>Dear Natalia,
>>>We advise AG nodes to use the default value of OFF for AGC/SL as
>>>trying to  configure it causes all kinds of strange audio noises.
>>>
>>>This is also the advice from inSORS.
>>>
>>>AGC tries to control the gain and SL expands the sound of anything
>>>quiet. Unless you make any progress with the parameters, try switching
>>> AGC/SL off.
>>>
>>>Regards,
>>>Paul Kuchar, AGSC
>>>Collaborative Working Developments
>>>==============================>>Manchester Computing, Kilburn Building
>>>University of Manchester, M13  9PL, United Kingdom
>>>==============================>>Tel: +44(0)161-275 0668 Fax:
>>>+44(0)161-275 6800 / 6040
>>>Email:
>>><mailto:Paul.Kuchar at manchester.ac.uk>Paul.Kuchar at manchester.ac.uk
>>>
>>>
>>>----------
>>>From: owner-ag-tech at mcs.anl.gov [mailto:owner-ag-tech at mcs.anl.gov] On
>>>Behalf Of Natalia Costas Lago
>>>Sent: 17 February 2005 16:25
>>>To: ag-tech
>>>Subject: [AG-TECH] XAP setup - urgent
>>>
>>>
>>>
>>>Dear all,
>>>
>>>
>>>We are quite in an emergency: our inauguration is about to happen
>>>(25th
>>> february). And we still have too many audio problems. I've followed
>>>some  advices given here and given by te people from clearone and they
>>>helped us  to understand the proceedings to configure the XAP
>>>settings. However there  are some issues still. I hope someone out
>>>there with much experience in  this equipment (and in audio systems)
>>>could help us:
>>>
>>>- We would like to know how to set the best AGC parameters (most
>>>importance) and Gating parameters. I think proper AGC settings would
>>>solve  a big part of our problems.
>>>- The group the mics belong is set to none, I hope this involves only
>>>gating issues (we want to hear whatever speaker wanna say, so we are
>>>not  interested in priority of one mic over another mic). May we have
>>>any  problems derived from this point?
>>>
>>>
>>>Any help is greatly appreciated.
>>>
>>>Thanx a lot.
>>>Kind regards.
>>>
>>>Natalia.
>>>
>>>-----------------------------------
>>>Natalia Costas Lago
>>>email: <mailto:natalia at cesga.es>natalia at cesga.es
>>>
>>>Centro de Supercomputacion de Galicia (CESGA)
>>>Avenida de Vigo, s/n Campus Sur
>>>15706 Santiago de Compostela - SPAIN
>>>Tel:   +34  981 56 98 10
>>>Fax:  +34  981 59 46 16
>>><http://www.cesga.es/>http://www.cesga.es/
>>
>>
>> ___________________________________________________________
>> Tom Coffin .......................... tcoffin at ncsa.uiuc.edu
>>
>>    NCSA-ACCESS                         cel: 703-477-5948
>>    901 North Stuart Street, #800       tel: 703-248-0105
>>    Arlington, Virginia 22203           fax: 703-248-0100
>>
>> _________________________ http://www.ncsa.uiuc.edu/~tcoffin
>
>
>
> -----------------------------------
> Natalia Costas Lago
> mailto: natalia at cesga.es
>
> Centro de Supercomputacion de Galicia (CESGA)
> Avenida de Vigo, s/n Campus Sur
> 15705 Santiago de Compostela - SPAIN
> Tel: +34  981 56 98 10
> Fax: +34  981 59 46 16
> http://www.cesga.es/

-----------------------------------
Natalia Costas Lago
mailto: natalia at cesga.es

Centro de Supercomputacion de Galicia (CESGA)
Avenida de Vigo, s/n Campus Sur
15705 Santiago de Compostela - SPAIN
Tel: +34  981 56 98 10
Fax: +34  981 59 46 16
http://www.cesga.es/