Digital voice vs analog

Matt All Messages By This Member #211489 We had a chat at work recently, between an "older" telco guy (me) and some twentysomethings. What instigated the conversation was a younger coworker mentioning that after a recent Teams update, he now had good audio. Another older coworker commented he missed the days of hearing a pin drop, and 45 mins later, we hung up. Some context... the younger fellow has a masters in computer science, the two older fellows have degrees from the UoHK. This follows along with the broadcast engineer topic. ? To summarize, in the mid 80s, a 64kbps channel could transmit audio at a quality level "superior" to todays digital systems which use far more resources. The young man couldn't wrap his head around the fact that having a $2,000 endpoint, connected to a myriad of networking devices, with "gig" speed, was inferior to $0 of compute, that didn't even require electricity at the user interface. We then devolved into codecs and how that 64k channel translated to G711. This then moved along to HD voice G722 and how it takes "compute" to do the additional encoding, which in the end, doesn't actually sound any better on a cell phone. ? We briefly touched on system complexity. He had no idea of how POTS worked, especially after walking through how many pieces of network gear is involved to get to an equivalent "switch point." He did recognize that for voice service, we really do have a more significant risk level using "internet." ? In summary, the current crop of sprouts has missed fundamental education in what makes things tick. ? Matt AL0R
Gary Cook #211490 开云体育 Thanks for sharing. Your conversation supports why it's so important to encourage bright students to go into engineering, where they are forced to learn the basics. Gary On 12/23/2024 8:24 AM, Matt wrote: toggle quoted message Show quoted text We had a chat at work recently, between an "older" telco guy (me) and some twentysomethings. What instigated the conversation was a younger coworker mentioning that after a recent Teams update, he now had good audio. Another older coworker commented he missed the days of hearing a pin drop, and 45 mins later, we hung up. Some context... the younger fellow has a masters in computer science, the two older fellows have degrees from the UoHK. This follows along with the broadcast engineer topic. ? To summarize, in the mid 80s, a 64kbps channel could transmit audio at a quality level "superior" to todays digital systems which use far more resources. The young man couldn't wrap his head around the fact that having a $2,000 endpoint, connected to a myriad of networking devices, with "gig" speed, was inferior to $0 of compute, that didn't even require electricity at the user interface. We then devolved into codecs and how that 64k channel translated to G711. This then moved along to HD voice G722 and how it takes "compute" to do the additional encoding, which in the end, doesn't actually sound any better on a cell phone. ? We briefly touched on system complexity. He had no idea of how POTS worked, especially after walking through how many pieces of network gear is involved to get to an equivalent "switch point." He did recognize that for voice service, we really do have a more significant risk level using "internet." ? In summary, the current crop of sprouts has missed fundamental education in what makes things tick. ? Matt AL0R
wj9jrg All Messages By This Member #211491 Very good summary Matt! Andy toggle quoted message Show quoted text On Mon, Dec 23, 2024 at 9:24?AM Matt via <al0r=[email protected]> wrote: We had a chat at work recently, between an "older" telco guy (me) and some twentysomethings. What instigated the conversation was a younger coworker mentioning that after a recent Teams update, he now had good audio. Another older coworker commented he missed the days of hearing a pin drop, and 45 mins later, we hung up. Some context... the younger fellow has a masters in computer science, the two older fellows have degrees from the UoHK. This follows along with the broadcast engineer topic. ? To summarize, in the mid 80s, a 64kbps channel could transmit audio at a quality level "superior" to todays digital systems which use far more resources. The young man couldn't wrap his head around the fact that having a $2,000 endpoint, connected to a myriad of networking devices, with "gig" speed, was inferior to $0 of compute, that didn't even require electricity at the user interface. We then devolved into codecs and how that 64k channel translated to G711. This then moved along to HD voice G722 and how it takes "compute" to do the additional encoding, which in the end, doesn't actually sound any better on a cell phone. ? We briefly touched on system complexity. He had no idea of how POTS worked, especially after walking through how many pieces of network gear is involved to get to an equivalent "switch point." He did recognize that for voice service, we really do have a more significant risk level using "internet." ? In summary, the current crop of sprouts has missed fundamental education in what makes things tick. ? Matt AL0R
Burt K6OQK Member Profile All Messages By This Member #211507 Since digital audio has been around for a bunch of years, and a lot of folks grew up listening to poor digital audio on cell phones and the like, many of the younger folks don't have a good reference on how good properly done analog audio can sound.? I find it curious that there's a belief that poor analog audio can be digitized and come out sounding better than good original analog audio. ? Burt, K6OQK
Gary Cook #211508 开云体育 Agree. Gary On 12/24/2024 10:21 AM, Burt K6OQK wrote: toggle quoted message Show quoted text Since digital audio has been around for a bunch of years, and a lot of folks grew up listening to poor digital audio on cell phones and the like, many of the younger folks don't have a good reference on how good properly done analog audio can sound.? I find it curious that there's a belief that poor analog audio can be digitized and come out sounding better than good original analog audio. ? Burt, K6OQK
Matt All Messages By This Member #211509 开云体育 THIS!!!! >>>> there's a belief that poor analog audio can be digitized and come out sounding better than good original analog audio. ? Matt AL0R ? toggle quoted message Show quoted text From: [email protected] <[email protected]> On Behalf Of Burt K6OQK via groups.io Sent: Tuesday, December 24, 2024 10:22 To: [email protected] Subject: Re: [repeater-builder] Digital voice vs analog ? Since digital audio has been around for a bunch of years, and a lot of folks grew up listening to poor digital audio on cell phones and the like, many of the younger folks don't have a good reference on how good properly done analog audio can sound.? I find it curious that there's a belief that poor analog audio can be digitized and come out sounding better than good original analog audio. ? Burt, K6OQK
Chris Smart #211510 开云体育 Hi Burt. ? I’m in my late 40’s, so I remember analog landline telephone conversations. There was usually no perceptible delay between me and whoever I was talking to, at least on local calls. Talking on the phone felt comfortable. I could stay on the phone for hours with a good friend. For me, it isn’t just about sound quality, although that is part of it too. ? Nowadays, I find that extra delay between finishing what I’m saying and waiting for a response, or visa versa, very disconcerting. I find even the shortest phone conversations produce anxiety, and I’m pretty sure it is down to those short but noticeable delays. ? Am I alone in that? And those delays are everywhere – Zoom, Teams, cellphone calls. There’s no getting away from it. Even our so-called landline is actually routed over the Internet now. ? Is it all the ADC and DAC, plus the various codecs involved that slows everything down and makes it all feel AWKWARD AF?
Matt All Messages By This Member #211517 开云体育 Typical VoIP uses frames from 10-20ms. Plus a frame for buffer, plus transit time. Some devices increase the number of frames required as well, so it is not uncommon between two devices on the same network to have a 1/10^th second of delay. Then add network transit time and you may see another 1/10 second. ? The delay is real. I’ve worn many hats over the years and in a few of those cases, the move to digital actually interfered with operations to the point that certain users were authorized to go back to analog. Digital actually introduced an unacceptable level of risk. We may comment that a fraction of a second isn’t really critical, but it is. ? I’ve been involved in operations where the back and forth could have two or three users all transmit within a 1 second period and it had to happen. Contrast that with DMR, where I may have to wait a second before I get an admit notification. ? Even during some ssb HF roundtables, you can tell who is in the older crowd, as the conversation magically moves between several people and the casual listener can’t tell when one stops and the other starts. Then move to digital and you may have a 2-3 second delay before your audio is decoded on the other side. And heaven forbid the low rate melp, where it isn’t even a conversation, you are effectively recording and sending, where it may take a full minute for a 5 second statement to show up on the other side. CW operators simply slaughter those implementations on throughput, but yet here we are. ? “Progress” isn’t really progress. I’m sure we all recall the late night show that pitted the then world’s fastest texter with a pair of cw operators. The coders bested the texter with ease. We’re simply dumbing society down, reducing humans to the dumbest common denominator. ? Along the same lines you mention, it wasn’t that long ago that you walked into an electronics department and all the TVs were on…. Then we moved to digital and you could hear the various delays as different cpus were decoding. Now, you walk in and the TVs are on, but no audio. If you are lucky, they are piping in one channel of audio via overhead, so you can’t hear the digital trash from so many variations in delay. Analog delay lines were easy. Now you need hundreds of thousands of dollars in precision time equipment, not to mention end points that support it,? to even start. Timing on AV networks is a subset skill on its own, though with Dante, it is “somewhat” easier. ? So no, you are not alone. But the prime consumer now doesn’t care and doesn’t know any better. ? Matt AL0R ? toggle quoted message Show quoted text From: [email protected] <[email protected]> On Behalf Of Chris Smart via groups.io Sent: Tuesday, December 24, 2024 10:29 To: [email protected] Subject: Re: [repeater-builder] Digital voice vs analog ? Hi Burt. ? I’m in my late 40’s, so I remember analog landline telephone conversations. There was usually no perceptible delay between me and whoever I was talking to, at least on local calls. Talking on the phone felt comfortable. I could stay on the phone for hours with a good friend. For me, it isn’t just about sound quality, although that is part of it too. ? Nowadays, I find that extra delay between finishing what I’m saying and waiting for a response, or visa versa, very disconcerting. I find even the shortest phone conversations produce anxiety, and I’m pretty sure it is down to those short but noticeable delays. ? Am I alone in that? And those delays are everywhere – Zoom, Teams, cellphone calls. There’s no getting away from it. Even our so-called landline is actually routed over the Internet now. ? Is it all the ADC and DAC, plus the various codecs involved that slows everything down and makes it all feel AWKWARD AF?
Gary Cook #211518 开云体育 You're not alone in this. With POTS lines, you and the other party could both talk at the same time, where we can't now. Today, the delays cause confusion and aggravation. Gary On 12/24/2024 10:29 AM, Chris Smart wrote: toggle quoted message Show quoted text Hi Burt. ? I’m in my late 40’s, so I remember analog landline telephone conversations. There was usually no perceptible delay between me and whoever I was talking to, at least on local calls. Talking on the phone felt comfortable. I could stay on the phone for hours with a good friend. For me, it isn’t just about sound quality, although that is part of it too. ? Nowadays, I find that extra delay between finishing what I’m saying and waiting for a response, or visa versa, very disconcerting. I find even the shortest phone conversations produce anxiety, and I’m pretty sure it is down to those short but noticeable delays. ? Am I alone in that? And those delays are everywhere – Zoom, Teams, cellphone calls. There’s no getting away from it. Even our so-called landline is actually routed over the Internet now. ? Is it all the ADC and DAC, plus the various codecs involved that slows everything down and makes it all feel AWKWARD AF?
Chuck Kelsey All Messages By This Member #211520 开云体育 Yep, 100% agree with you. The delays suck big time. One reason I refuse to put any audio delay boards on repeater controllers. Chuck WB2EDV On 12/24/2024 11:29 AM, Chris Smart via groups.io wrote: toggle quoted message Show quoted text Hi Burt. ? I’m in my late 40’s, so I remember analog landline telephone conversations. There was usually no perceptible delay between me and whoever I was talking to, at least on local calls. Talking on the phone felt comfortable. I could stay on the phone for hours with a good friend. For me, it isn’t just about sound quality, although that is part of it too. ? Nowadays, I find that extra delay between finishing what I’m saying and waiting for a response, or visa versa, very disconcerting. I find even the shortest phone conversations produce anxiety, and I’m pretty sure it is down to those short but noticeable delays. ? Am I alone in that? And those delays are everywhere – Zoom, Teams, cellphone calls. There’s no getting away from it. Even our so-called landline is actually routed over the Internet now. ? Is it all the ADC and DAC, plus the various codecs involved that slows everything down and makes it all feel AWKWARD AF?
Chris Smart #211521 开云体育 ? Along the same lines you mention, it wasn’t that long ago that you walked into an electronics department and all the TVs were on…. ? I sure don’t miss the 15 kHz scan frequency wine from a bank of CRT screens though. That used to give me a headache really fast as a kid.
Matt All Messages By This Member #211522 开云体育 I couldn’t quite hear what you said…. ? Matt AL0R ? toggle quoted message Show quoted text From: [email protected] <[email protected]> On Behalf Of Chris Smart via groups.io Sent: Tuesday, December 24, 2024 11:13 To: [email protected] Subject: Re: [repeater-builder] Digital voice vs analog ? ? Along the same lines you mention, it wasn’t that long ago that you walked into an electronics department and all the TVs were on…. ? I sure don’t miss the 15 kHz scan frequency wine from a bank of CRT screens though. That used to give me a headache really fast as a kid.
n5qs All Messages By This Member #211524 开云体育 I have my flame suit on. I have seen all the symptoms below and have been a commercial radio dealer for more than 30 years and an amateur for almost that long. In my opinion (not worth much these days) DMR should be illegal for public safety, it introduces too many possibilities for lost communications and is very unreliable. A 6.25 bandwidth FDMA digital channel, while it does introduce less than perfect audio does eliminate the unreliability of any TDMA mode while using the same bandwidth. On a side note the 6.25 digital has better range and audio quality than the same mode in 12.5 bandwidth and I cant explain that but have given it side by side comparisons and it works every time. Roger On 12/24/2024 11:00 AM, Matt wrote: toggle quoted message Show quoted text Typical VoIP uses frames from 10-20ms. Plus a frame for buffer, plus transit time. Some devices increase the number of frames required as well, so it is not uncommon between two devices on the same network to have a 1/10^th second of delay. Then add network transit time and you may see another 1/10 second. ? The delay is real. I’ve worn many hats over the years and in a few of those cases, the move to digital actually interfered with operations to the point that certain users were authorized to go back to analog. Digital actually introduced an unacceptable level of risk. We may comment that a fraction of a second isn’t really critical, but it is. ? I’ve been involved in operations where the back and forth could have two or three users all transmit within a 1 second period and it had to happen. Contrast that with DMR, where I may have to wait a second before I get an admit notification.
Jim Barbour All Messages By This Member #211527 On 12/24/2024 12:37 PM, n5qs via groups.io wrote: I have my flame suit on. I have seen all the symptoms below and have been a commercial radio dealer for more than 30 years and an amateur for almost that long. In my opinion (not worth much these days) DMR should be illegal for public safety, it introduces too many possibilities for lost communications and is very unreliable. Honestly, DMR is MUCH better then P25 Phase II, or even Phase I on a trunked system, when you talk about things like channel access lag and audio quality. I don't think I have heard any digital audio format that sounds worse than Phase II trunking. Then there's the patch thing-right now a Phase II system has some legacy VHF channels patched in to the trunk on different TG's. The voice lag there between VHF and the trunk, or from the trunk to VHF is more than a full second. Easily. Plus muddy and overdriven. Yuck. But I have yet to see a trunked system than can even come close to EDACS on channel access. I did an experiment once where I keyed two radios at the same instant-one using conventional CTCSS simplex, and the other through an EDACS system 5 miles away. The two receive radios I setup opened at the same time, as close as I could tell by ear. So within maybe 5 mS at most. Of course, voice was analog, so no lag there at all. EDACS was far and away the best trunking format ever, bar none. Shame it's not supported anymore.
Chuck Kelsey All Messages By This Member #211534 Agreed. The EDACS demo I heard years ago was WOW. Then all the digital modes came along to ruin things. Chuck WB2EDV toggle quoted message Show quoted text EDACS was far and away the best trunking format ever, bar none. Shame it's not supported anymore.
MILLIN SEE All Messages By This Member #211536 Edacs was Imbe...similar to D star Millin toggle quoted message Show quoted text ----- Original Message ----- From: Chuck Kelsey via groups.io <wb2edv@...> To: [email protected] Sent: Tue, 24 Dec 2024 12:30:51 -0700 (MST) Subject: Re: [repeater-builder] Digital voice vs analog Agreed. The EDACS demo I heard years ago was WOW. Then all the digital modes came along to ruin things. Chuck WB2EDV EDACS was far and away the best trunking format ever, bar none. Shame it's not supported anymore.
Jim Barbour All Messages By This Member #211537 Not quite. EDACS is the trunking protocol, and it used analog voice channels...unless you went the optional Pro-Voice path, which kept the EDACS control channel protocol, but added Pro-Voice voice channels. And Pro-Voice could be conventional as well-not trunked. toggle quoted message Show quoted text On 12/24/2024 3:47 PM, MILLIN SEE via groups.io wrote: Edacs was Imbe...similar to D star Millin ----- Original Message ----- From: Chuck Kelsey via groups.io <wb2edv@...> To: [email protected] Sent: Tue, 24 Dec 2024 12:30:51 -0700 (MST) Subject: Re: [repeater-builder] Digital voice vs analog Agreed. The EDACS demo I heard years ago was WOW. Then all the digital modes came along to ruin things. Chuck WB2EDV EDACS was far and away the best trunking format ever, bar none. Shame it's not supported anymore.
Chuck Kelsey All Messages By This Member #211539 开云体育 The demo I heard was using analog voice. Chuck On 12/24/2024 3:47 PM, MILLIN SEE via groups.io wrote: toggle quoted message Show quoted text Edacs was Imbe...similar to D star Millin ----- Original Message ----- From: Chuck Kelsey via groups.io <wb2edv@...> To: [email protected] Sent: Tue, 24 Dec 2024 12:30:51 -0700 (MST) Subject: Re: [repeater-builder] Digital voice vs analog Agreed. The EDACS demo I heard years ago was WOW. Then all the digital modes came along to ruin things. Chuck WB2EDV EDACS was far and away the best trunking format ever, bar none. Shame it's not supported anymore.
Jim Barbour All Messages By This Member #211540 Oh, yeah, and Pro-Voice didn't come along til much later. The first digital voice format was Voice-Guard. It was only encrypted, and that was the only reason to use it. Then eventually came Aegis, then Pro-Voice, either of which could be encrypted or not. toggle quoted message Show quoted text On 12/24/2024 5:07 PM, Jim Barbour via groups.io wrote: Not quite. EDACS is the trunking protocol, and it used analog voice channels...unless you went the optional Pro-Voice path, which kept the EDACS control channel protocol, but added Pro-Voice voice channels. And Pro-Voice could be conventional as well-not trunked. On 12/24/2024 3:47 PM, MILLIN SEE via groups.io wrote: Edacs was Imbe...similar to D star Millin ----- Original Message ----- From: Chuck Kelsey via groups.io <wb2edv@...> To: [email protected] Sent: Tue, 24 Dec 2024 12:30:51 -0700 (MST) Subject: Re: [repeater-builder] Digital voice vs analog Agreed. The EDACS demo I heard years ago was WOW. Then all the digital modes came along to ruin things. Chuck WB2EDV EDACS was far and away the best trunking format ever, bar none. Shame it's not supported anymore.
MILLIN SEE All Messages By This Member #211541 True, but province was imbe... toggle quoted message Show quoted text ----- Original Message ----- From: Jim Barbour via groups.io <wd8chl@...> To: [email protected] Sent: Tue, 24 Dec 2024 15:07:48 -0700 (MST) Subject: Re: [repeater-builder] Digital voice vs analog Not quite. EDACS is the trunking protocol, and it used analog voice channels...unless you went the optional Pro-Voice path, which kept the EDACS control channel protocol, but added Pro-Voice voice channels. And Pro-Voice could be conventional as well-not trunked. On 12/24/2024 3:47 PM, MILLIN SEE via groups.io wrote: Edacs was Imbe...similar to D star Millin ----- Original Message ----- From: Chuck Kelsey via groups.io <wb2edv@...> To: [email protected] Sent: Tue, 24 Dec 2024 12:30:51 -0700 (MST) Subject: Re: [repeater-builder] Digital voice vs analog Agreed. The EDACS demo I heard years ago was WOW. Then all the digital modes came along to ruin things. Chuck WB2EDV EDACS was far and away the best trunking format ever, bar none. Shame it's not supported anymore.

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