Loud Environment - Digital Mode

[sammyg512]

He is using AGC. Adjusting the mic gain isn't going to do anything.

I've enabled AGC, but also found turning the Gain down and turning AGC off, seems to make it worse. I increased the gain, with AGC off and it seems to be more legable. Using AGC does help a little bit. I can remember using some DP4400E radios at an event, and they worked perfectly in the stage pit with just a standard D Loop headset. I might see if i can contact the hire company they used, to see if they could send me the codeplug they use.

 

[Ubbe]

All digital system use algoritms to reduce the number of data needed to be transmitted to fit inside a channels bandwidth. At the other end the algoritm tries to guess what data bits that have been removed and tries to restore them. It works fairly well if the speech levels are accurate. Too much or too little speech audio level with make the sound quality worse and also having other loud audio mixed in with the speech will make it an almost impossible task.

The same goes for noise cancelling features in software that I haven't heard any that doesn't massacre the audio quality.

Digital systems has a much more narrow dynamic range for audio compared to analog that has a huge dynamic range. Setting levels then becomes extremely critical to not overload any stage from the microphone amp to the DSP processing but then also cannot use too low audio levels that will even further reduce the dynamic range. Using AGC are a must in digital systems.

I have found that naming channels to LOUD and NORMAL that only use different sound profiles will help a lot when users can see on their display what mode they have chosen instead of button pushing to change modes. If will be impossible to use only one audio setting to handle both a situation when there are loud music with a lot of people and users shout into their mics that also can handle a quiet venue at a normal audio environment before any people are let in.

/Ubbe

 

[sammyg512]

All digital system use algoritms to reduce the number of data needed to be transmitted to fit inside a channels bandwidth. At the other end the algoritm tries to guess what data bits that have been removed and tries to restore them. It works fairly well if the speech levels are accurate. Too much or too little speech audio level with make the sound quality worse and also having other loud audio mixed in with the speech will make it an almost impossible task.

The same goes for noise cancelling features in software that I haven't heard any that doesn't massacre the audio quality.

Digital systems has a much more narrow dynamic range for audio compared to analog that has a huge dynamic range. Setting levels then becomes extremely critical to not overload any stage from the microphone amp to the DSP processing but then also cannot use too low audio levels that will even further reduce the dynamic range. Using AGC are a must in digital systems.

I have found that naming channels to LOUD and NORMAL that only use different sound profiles will help a lot when users can see on their display what mode they have chosen instead of button pushing to change modes. If will be impossible to use only one audio setting to handle both a situation when there are loud music with a lot of people and users shout into their mics that also can handle a quiet venue at a normal audio environment before any people are let in.

/Ubbe

That makes sense, would it be a good idea to have an increased gain mode for Digital, in a loud environment?

 

[Ubbe]

That makes sense, would it be a good idea to have an increased gain mode for Digital, in a loud environment?

For radios that use profiles/personalities for audio settings you use extra high audio to the speaker for a loud setting and a lower gain setting for the mic as people automatically raise their voice if their ears hear a loud noise level. It is impossible to try and tech people that they do not need to shout into the mic.

/Ubbe

 

[sammyg512]

For radios that use profiles/personalities for audio settings you use extra high audio to the speaker for a loud setting and a lower gain setting for the mic as people automatically raise their voice if their ears hear a loud noise level. It is impossible to try and tech people that they do not need to shout into the mic.

/Ubbe

I've tried to lecture them how to use radios, but its not working! I've even tried to explain to them, that the headsets mic is at the top of the button, so make sure you talk straight into that, instead of pressing the button and talking away from the mic. AGR seems to have helped a bit. I've sent my codeplug to a company that specilise in event radio hire, and they said theyre more than happy to take a look at the settings, to see if there is anything they can do. Hopefully, they will find a way to make it work better, otherwise ill stick to analogue.

It seems that also, some of the radio users are used to Analogue radios, and dont understand that voice sounds a little different on Digital ones. Trying to explain that to the users, is like pulling teeth.

 

[redrock2002]

I've tried to lecture them how to use radios, but its not working! I've even tried to explain to them, that the headsets mic is at the top of the button, so make sure you talk straight into that, instead of pressing the button and talking away from the mic. AGR seems to have helped a bit. I've sent my codeplug to a company that specilise in event radio hire, and they said theyre more than happy to take a look at the settings, to see if there is anything they can do. Hopefully, they will find a way to make it work better, otherwise ill stick to analogue.

It seems that also, some of the radio users are used to Analogue radios, and dont understand that voice sounds a little different on Digital ones. Trying to explain that to the users, is like pulling teeth.

Welcome to the club. EVERY analag radio user that has switched over to Digital in any capacity has this very issue. We have 7550e radios in a loud manufacturing facility and it was a bloody nightmare when we went from analag over to Cap+. I will tell you that the user has to give the mic a strong voice signal without yelling into mic and you must speak directly at the mic. We use the 4025 noise cancelling mics with Enhanced Noise Cancellation enabled. All other "AI" settings like AGC and AF need to be off.

 

[redrock2002]

I've had a play with the settings, and its a little bit better, this is what I have the audio profile set to. The reason i'd like to move them all to Digital, is so we can use the Privacy Function, as there is a lot of venues locally that use Analog Radios, and sometimes get interferance issues, on the frequancys OFCOM have allocated to me.

Sammy I am not seeing the RX audio Leveling in your screenshot. They are there on my 7550e radios. Maybe your radios don't have that setting unless you need newer firmware.

 

[sammyg512]

Sammy I am not seeing the RX audio Leveling in your screenshot. They are there on my 7550e radios. Maybe your radios don't have that setting unless you need newer firmware.

I think the E series does, but the standard ones don't. Not too sure though, but by DP4400e radios have more functions than the DP4400 radios

 

[K2NEC]

I think the E series does, but the standard ones don't. Not too sure though, but by DP4400e radios have more functions than the DP4400 radios

Not true at all, both support it. You need firmware past 2.06 to support RX Audio Leveling

 

[Spuff]

As said, this is a "code-book" vocoder doing its thing, whilst the absolute details of AMBE2(+) remain a complete mystery in essence it's doing a very strong compand/filter then doing a vector against it's table to match the sounds as best it can with seasoning for inflection/tone in the broadest of brushstrokes.
I know of a venue around these 'ere parts who have gone back to NFM (UK) for comms within the venue as DMR/AMBE was absolutely unusable with loud background music.
You might try a little experiment (and I know, do it quickly when nobody is listening) play some music in to a DMR mic and try and listen on another receiver - you'll note that it'll turn in to absolute mush, if you hear anything at all. Strictly that's probably against the regs' but for 5 seconds on a quiet frequency there are bigger crimes out there.

It won't sound much like music anyway...

A closer mic' might improve it, but this is a case of "nature of the beast" in my experience.

 

[buddrousa]

@sammyg512
Show the Radio Users this video

Say It Loud and Clear

Clear communications are critical to first responders. Motorola Solutions works with the International Association of Fire Chiefs to develop best practices to maximize intelligibility and overcome background noise on portable and mobile radios.

video.motorolasolutions.com

 

[sammyg512]

As said, this is a "code-book" vocoder doing its thing, whilst the absolute details of AMBE2(+) remain a complete mystery in essence it's doing a very strong compand/filter then doing a vector against it's table to match the sounds as best it can with seasoning for inflection/tone in the broadest of brushstrokes.
I know of a venue around these 'ere parts who have gone back to NFM (UK) for comms within the venue as DMR/AMBE was absolutely unusable with loud background music.
You might try a little experiment (and I know, do it quickly when nobody is listening) play some music in to a DMR mic and try and listen on another receiver - you'll note that it'll turn in to absolute mush, if you hear anything at all. Strictly that's probably against the regs' but for 5 seconds on a quiet frequency there are bigger crimes out there.

It won't sound much like music anyway...

A closer mic' might improve it, but this is a case of "nature of the beast" in my experience.

I've just tried that little experiment, on DMR, just scrambled noise, and in Analog mode, i could hear it clear. I think for the usecase of a night club, Analog seems to work better, as the voices are more clear, and actually legable. I've set up 2 zones, one for Digital channels, for standard use, and a zone for analog channels, for use in nightclubs etc...

 

[sammyg512]

All digital system use algoritms to reduce the number of data needed to be transmitted to fit inside a channels bandwidth. At the other end the algoritm tries to guess what data bits that have been removed and tries to restore them. It works fairly well if the speech levels are accurate. Too much or too little speech audio level with make the sound quality worse and also having other loud audio mixed in with the speech will make it an almost impossible task.

The same goes for noise cancelling features in software that I haven't heard any that doesn't massacre the audio quality.

Digital systems has a much more narrow dynamic range for audio compared to analog that has a huge dynamic range. Setting levels then becomes extremely critical to not overload any stage from the microphone amp to the DSP processing but then also cannot use too low audio levels that will even further reduce the dynamic range. Using AGC are a must in digital systems.

I have found that naming channels to LOUD and NORMAL that only use different sound profiles will help a lot when users can see on their display what mode they have chosen instead of button pushing to change modes. If will be impossible to use only one audio setting to handle both a situation when there are loud music with a lot of people and users shout into their mics that also can handle a quiet venue at a normal audio environment before any people are let in.

/Ubbe

I've literally tried everything on the audio settings to make is workable, but nothing seems to make much of a differance. I'm going to update the firmware on the radios, as they're currently all running different firmwares, and probably revert back to Analog. The team are used to Analog, and i've heard a few mumbles about the different sound in voice over Digital. I'm personally used to Digital Radios, however, for the environment, it seems Analog is the way to go at the moment.

 

[asd6845]

I've literally tried everything on the audio settings to make is workable, but nothing seems to make much of a differance. I'm going to update the firmware on the radios, as they're currently all running different firmwares, and probably revert back to Analog. The team are used to Analog, and i've heard a few mumbles about the different sound in voice over Digital. I'm personally used to Digital Radios, however, for the environment, it seems Analog is the way to go at the moment.

If the budget allows, may be consider getting the club security upgraded to the Motorola R7. Having dual mics allows for exceptional noise cancelation.

Here is a couple YouTube videos showing it working.

This video compares the R7 to the XPR7550e to the AnyTone 878

Here's another with the R7 noise canceling off and on.