> At 5:00 PM -0600 on 7/11/04, Rich Adamson wrote: > >I'm toying with adding a feature request to provide some sort of > >gain setting for voicemail when accessed from "certain" interfaces. > >Maybe something like voicemail=6.0 (db) within a specific channel > >section of zapata.conf corresponding to a pstn line. > > > >Situation: > >1. Someone calls into asterisk and leaves a voicemail. The sound > >is recorded at some volume well below 0 db, and is directly related > >to the distance asterisk is from the central office (pstn cable > >loss) plus whatever distance the user placing the call is from > >his/her central office. > >2. I receive a text message that a voicemail was left. > >3. I call into asterisk remotely (assume from a cell phone) and > >retreive the voicemail. My location creates another xx db of loss > >between myself and asterisk, and voicemail can hardly be heard. > > > >Actual Measured Values: > >1. Asterisk is 5.6 db from the central office. Called from one > >pstn line, through the central office, to asterisk and sending a > >1004 hz tone at 0db. Recorded the tone into voicemail. (Tone should > >have been recorded at about 11.2db, two times the cable loss) > >2. Called into asterisk again, this time to retreive the voicemail > >and measured the 1004 hz tone from voicemail. It was -36db "actual". > >This retreival added another 11.2db of loss due to pstn interfaces > >and plant loss. > >3. The calls were through a TDM FXO module with rx and tx gains > >set to 0. (Changing rx and tx gain to +3 db and repeating the test > >resulted in a measured -30.5db signal, but these settings create > >unwanted echo issues. Therefore adjusting channel gain is not an > >option.) > > > >The end result is that retreiving any voicemail message left from > >a distant location and retreived from a distant location can hardly > >be heard. By adding the proposed voicemail=6.0 statement to the > >appropriate channel, any calls connected to voicemail via that > >channel would effectively increase transmission levels by 6db (or > >whatever the setting happened to be). In this example case, the > >setting would increase the vm volume by 12db (or about 24db measured > >in the above). > > > >Anyone have any thoughts on this? > > > >Rich > > Rich - > I'll say that this would be very useful. Regardless of where the > loss is being inserted, it still exists. > > I like the idea of associating the voicemail db adjustment on a > per-channel basis. I don't want to have to dink around with yelling > at the telco to fix something that "just works" otherwise. Their > answer will be "Well, turn up the volume on your phone!" which is > exactly what your proposed patch will do. A simple trial-and-error > process should be able to sort out the proper adjustment on any > typical system that doesn't have radical db changes across time. I'm > heartily in favor of this idea; I'll even throw a donation towards > it, if you have a PayPal account. > > Another cool feature would be app_volume, which would turn up/turn > down tx/rx levels dynamically, but that's left for a different day, > and after we have an enhanced app_dial that lets single-digit dtmf > sequences jump to dialplan routines and then can reconnect bridged > calls. See my various rantings about this in months (years!) past. > When I get some spare time (ha ha ha) I should really learn how to > code this stuff... > > JT
The above "feature" request has been entered as bug #2023. It also appears that VM has an issue (by itself) with recording/playing volume. Transmitting a 1004hz tone at 0db through a ata186 (set for -1db fxs loss), and then retreiving the same VM results in that tone measured at ~ -10db. Doing the same from a pstn location (via TDM FXO) suggests the same -10db loss (in addition to the pstn loss). Zapata.conf rxgain and txgain set to 0. Using CVS-HEAD-07/12/04, but same result with CVS-HEAD-07/1/04. Entered as bug #2022. Add comments to either if you'd like. _______________________________________________ Asterisk-Users mailing list [EMAIL PROTECTED] http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
