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
Let's see you have 11.2 db of loss from the phone you are using to call in on and the FXO interface on Asterisk. Retreiving voice mail would add another 11.2 or a total of 22.4 db. But your measured tone level was 36db. In other words the FXO interface and Asterisk introduced about 14 db of loss. I would find this amount of loss to be unacceptable. Rather than hack at the code, why not find this additional loss? A PBX or telco switch should not introduce this much loss, IMHO. Lyle ----- Original Message ----- From: "Rich Adamson" <radamson@routers.com> To: "Asterisk-a-users-list" <asterisk-users@lists.digium.com> Sent: Sunday, July 11, 2004 6:00 PM Subject: [Asterisk-Users] feature - VM gain adjust?> > 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 > > > > > _______________________________________________ > Asterisk-Users mailing list > Asterisk-Users@lists.digium.com > http://lists.digium.com/mailman/listinfo/asterisk-users > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-users >
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? > >RichRich - 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
Hello>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.That gets my vote. We experience this low-volume voicemail problem. (and I spent a long time looking for the proposed setting to tweak!) Bob
> That gets my vote. We experience this low-volume voicemail > problem. (and I spent a long time looking for the proposed > setting to tweak!)Think about a dynamic sound compressor that would possibly auto-adjust.
Hello>> That gets my vote. We experience this low-volume voicemail >> problem. (and I spent a long time looking for the proposed >> setting to tweak!) > >Think about a dynamic sound compressor that would possibly auto-adjust.Are you suggesting such a thing exists, or that that would be a proposed future application? Bob
> Are you suggesting such a thing exists, or that that would be a > proposed future application?I propose to think if an AGC / dynamic compressor could be used instead of a config variable. Most sound editors have modules for this.