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Help Does Google modify callers' voices broadcast from the Pixel's speaker to prevent recording by PC voice recorder apps?

G

gfr92y

Newbie
My original thread title (question) was: Why don't voice recorder PC apps record callers' voices when the phone is on speaker?

However, I would not be surprised in the least if Google modified callers' voices broadcast from the Pixel's speaker to prevent their voices from being recorded by PC voice recorder apps.

I look forward to your comments, thought, theories, and facts!

Thanks!

gfr92y

Here are the particulars...
  • Phone: Pixel 6 Pro with Android Version 13
  • PC: 64-bit HP Envy x360 with Windows 11 Home Edition Version 10.0.22621 Build 22621
  • Mic: Kingston HyperX Solocast Model SLC001
  • Apps
    • Stefan "Heufneutje" Frijters' Audio and Voice Recorder Version 2.1.0
    • Microsoft Sound Recorder Version 11.2304.25.0
    • Audacity 3.3.1
  • Recording and Playback Behaviour
    • The sound level meters in all three apps report suitable sound levels for me and the callers whose voices are being broadcast from the phone's speaker.
    • Suitable sound levels for the callers and me are achieved by carefully positioning the mic relative to the phone's speaker and my mouth.
    • During playback, my voice is crisp and clear, but the callers' voices are essentially inaudible, and during the very brief periods of time when the callers' voices were detectable, their speech was incomprehensible.





 
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What magic signal do you think they are adding that allows the human ear to hear the voices normally but stymies mechanical recording? If they were outputting any additional sound within the audible range you would hear the distortion yourself. A signal at a different frequency would be ineffective (because it would not affect the frequencies of interest). For sure you could add noise that would make life difficult for a mic, relying on the human brain's pattern recognition abilities to let you understand what is being said, but if you did that the voice would definitely not be normal or clear to you.

If you have 2 speakers you can use interference (in the specific sense of interference of waves, not just the generic term "interference") to cancel out a sound in a particular location. But that only works if you have 2 speakers and some electronics which knows where they both are and where you want the sound to be cancelled, so that one can output an inverse waveform with the correct amplitude and phase offset to achieve the cancellation where you want it. If you try to put a destructive interference out through the single speaker you get no sound out at all (the 2 electrical signals sent to the speaker would cancel each other out and the speaker would not receive any signal at all, and hence output no sound whatsoever). There is no way that a single phone can do this.

If you were using a radio mic then you could imagine outputting a radio signal to jam its communications with the computer, but that would not affect just one side of the conversation. And I believe that's a USB mic, so we can dismiss that theory. Plus you need to be careful about using jammers in public places: even if you restrict them to the unlicensed radio bands (so that they are not illegal to operate), which you might guess is what a radio mic would use, they could easily affect other devices that use those bands (because you'd have to jam the entire band, not just a narrow channel, since you don't know which channel the radio mic is set to use). It would be a commercially risky move for Google to put something like that into a phone, as the potential downsides would way exceed any benefit.

Plus, on that last point, what would the commercial benefit of Google doing anything like this be? Google only gain from it if it increases sales, but it can't do that if it's an unadvertised, hidden feature.

My friend William of Occam suggests you look for a simpler explanation.
 
Hadron said:
What magic signal...
Click to expand...

Can you propose an alternate hypothesis for the previously described phenomenon?

Here is another data point...

When I connected my Bluetooth speaker to my phone and recorded the caller's voice through the Bluetooth speaker, the recording of both voices was spot on and when I turned off the Bluetooth speaker in mid-conversation, the phone reverted to its internal speaker and from that point forward, the caller's voice was again essentially inaudible, and during the very brief periods of time when the caller's voice was detectable, it was incomprehensible.

Consider the same person speaking... Using the Bluetooth speaker, the caller's voice recorded well... Using the Pixel 6 Pro speaker, the caller's voice was obfuscated... How do you explain that?
 
Hadron said:
What magic signal ... My friend William of Occam suggests you look for a simpler explanation.
Click to expand...

If you have a Pixel 6 Pro, try recording a conversation using the phone's internal speaker, an external mic, and a PC voice recorder app, and share your experience here, please.

gfr92y
 
gfr92y said:
If you have a Pixel 6 Pro, try recording a conversation using the phone's internal speaker, an external mic, and a PC voice recorder app, and share your experience here, please.

gfr92y
Click to expand...

Different speakers and/or different recording devices are going to give you a close to or slightly different sound, and I emphasize slightly.
 
AugieTN said:
Different speakers and/or different recording devices are going to give you a close to or slightly different sound, and I emphasize slightly.
Click to expand...

I understand what you are saying, but how does what you are saying jive with the observations I have reported?

Furthermore, do you have any experience with the Pixel 6 Pro supporting your contentions or that are contrary to my experiences?
 
gfr92y said:
I understand what you are saying, but how does what you are saying jive with the observations I have reported?

Furthermore, do you have any experience with the Pixel 6 Pro supporting your contentions or that are contrary to my experiences?
Click to expand...

LOL! Are you like practicing for a debate class?
 
gfr92y said:
If you have a Pixel 6 Pro, try recording a conversation using the phone's internal speaker, an external mic, and a PC voice recorder app, and share your experience here, please.
Click to expand...
I don't have a Pixel 6 Pro.

gfr92y said:
Can you propose an alternate hypothesis for the previously described phenomenon?
Click to expand...
Without seeing your setup or being able to play? Probably not. I'm an empiricist (specifically a research physicist), so I would play around, test the different variables. I'd probably start with the question "how directional is your mic?", then do some tests on just recording the output of the speaker (not bothering about getting a recording of your own voice), testing both with handsfree calls and just playing back voice samples (podcasts or audiobooks) through the speaker (which would test whether there is anything different about voice calls ). If you can record voice OK that way then the problem was probably in mic positioning. If not I'd look at the other variables (actually being me I'd throw the mic output through a spectrum analyser while I was doing this...).

Since you say you had the levels good for the phone beforehands, how did you test that? Did you test with a phone call? Did you monitor during the call?

gfr92y said:
Here is another data point...

When I connected my Bluetooth speaker to my phone and recorded the caller's voice through the Bluetooth speaker, the recording of both voices was spot on and when I turned off the Bluetooth speaker in mid-conversation, the phone reverted to its internal speaker and from that point forward, the caller's voice was again essentially inaudible, and during the very brief periods of time when the caller's voice was detectable, it was incomprehensible.

Consider the same person speaking... Using the Bluetooth speaker, the caller's voice recorded well... Using the Pixel 6 Pro speaker, the caller's voice was obfuscated... How do you explain that?
Click to expand...
Volume, direction, frequency response of the BT speaker will all be different, so my first guess would still be to look at whether the mic was picking up the phone speaker properly. In fact if you were intending to use the BT speaker for the call and did your level tests using that it would mean that those tests did not confirm that the levels from the phone speaker were correct.

I'm not there, I can't see or experiment with your setup, so my ability to work out the cause is limited. But "Google add a special tone that is inaudible but somehow disables any recording equipment, which they only output from the phone speaker but not over BT, just in order to stop any external mic recording both sides of a phone call, which they only emit while the caller is speaking and not at other times, and don't tell anyone about, and which has no obvious benefit to them" would be extremely low on my list of hypotheses even if I knew nothing about whether this was technically feasible or not.
 
Hadron said:
I don't have a Pixel 6 Pro.


Without seeing your setup or being able to play? Probably not. I'm an empiricist (specifically a research physicist), so I would play around, test the different variables. I'd probably start with the question "how directional is your mic?", then do some tests on just recording the output of the speaker (not bothering about getting a recording of your own voice), testing both with handsfree calls and just playing back voice samples (podcasts or audiobooks) through the speaker (which would test whether there is anything different about voice calls ). If you can record voice OK that way then the problem was probably in mic positioning. If not I'd look at the other variables (actually being me I'd throw the mic output through a spectrum analyser while I was doing this...).

Since you say you had the levels good for the phone beforehands, how did you test that? Did you test with a phone call? Did you monitor during the call?


Volume, direction, frequency response of the BT speaker will all be different, so my first guess would still be to look at whether the mic was picking up the phone speaker properly. In fact if you were intending to use the BT speaker for the call and did your level tests using that it would mean that those tests did not confirm that the levels from the phone speaker were correct.

I'm not there, I can't see or experiment with your setup, so my ability to work out the cause is limited. But "Google add a special tone that is inaudible but somehow disables any recording equipment, which they only output from the phone speaker but not over BT, just in order to stop any external mic recording both sides of a phone call, which they only emit while the caller is speaking and not at other times, and don't tell anyone about, and which has no obvious benefit to them" would be extremely low on my list of hypotheses even if I knew nothing about whether this was technically feasible or not.
Click to expand...

But google does have a history of actively working to prevent recording of phone calls.
 
Someone... Prove me wrong or prove me right, but stop with empirical this and electromagnetic that...

Any pixel running Android 13 and MS Sound Recorder!

Does it work for you?
 
When my wife comes home tonight, I will try to record as described above but with an iPhone and report the results
 
gfr92y said:
But google does have a history of actively working to prevent recording of phone calls
Click to expand...
The way you're presenting that statement gives the wrong impression

I remember reading that Google was stopping recording apps to help Google to stay on the safe side of the law in all jurisdictions, since some states require all parties to be aware of the recording.
 
Yes.

And there's also a difference between making it difficult for an app on the phone to record both sides of the call, which is easy to do technically, and which, as pointed out above, they may have a motivation for doing, and implementing some magical system to interfere with the ability of external equipment to record, which would be nothing to do with Google and so would have no legal implications whatsoever for them if someone did it.

When you propose a tinfoil hat explanation the onus is not on anyone to prove you wrong. Extraordinary claims require extraordinary evidence, and the onus is on you to prove it. The simplest explanation, if you'll forgive me, is that you messed-up but don't know what was wrong.

To give one example: you say in your first post that you checked the levels before starting. You only reveal later that you were using a BT speaker for the call - that's relevant, but something nobody could guess. That's why it has to be you who investigates: asking for explanations based on incomplete information doesn't work. And I asked whether you checked the levels using the BT speaker or the phone and you chose not to answer, so let's spell it out: if you intended to use the BT speaker then that's what you should use to check the levels. If that is what you did, then any check you made using the speaker tells you nothing about whether the mic would pick up from the phone itself. So there is one possible explanation from the partial information you have provided in a piecemeal fashion, but I've no way of knowing what other relevant details you've not mentioned because you didn't think of them.

But sorry, given your attitude, that's my last suggestion. I'm done with this thread.
 
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No, Google does not modify callers' voices broadcast from the Pixel's speaker to prevent recording by PC voice recorder apps. The voice transmission from a Pixel phone's speaker during a call is not altered or modified by Google to prevent recording. The audio output is typically the same as any other call made from a mobile phone.

The ability to record phone calls may vary depending on the specific phone model, operating system, and any additional apps or settings that are in use. In some cases, certain phone models or operating systems may have built-in call recording features, while others may require third-party apps to enable call recording.

It's worth noting that recording phone conversations without the consent of all parties involved may be subject to legal restrictions or requirements depending on the jurisdiction you are in. It is important to comply with applicable laws and regulations regarding call recording and respect the privacy rights of others.
 
gfr92y said:
My original thread title (question) was: Why don't voice recorder PC apps record callers' voices when the phone is on speaker?

However, I would not be surprised in the least if Google modified callers' voices broadcast from the Pixel's speaker to prevent their voices from being recorded by PC voice recorder apps.

I look forward to your comments, thought, theories, and facts!

Thanks!

gfr92y

Here are the particulars...
  • Phone: Pixel 6 Pro with Android Version 13
  • PC: 64-bit HP Envy x360 with Windows 11 Home Edition Version 10.0.22621 Build 22621
  • Mic: Kingston HyperX Solocast Model SLC001
  • Apps
    • Stefan "Heufneutje" Frijters' Audio and Voice Recorder Version 2.1.0
    • Microsoft Sound Recorder Version 11.2304.25.0
    • Audacity 3.3.1
  • Recording and Playback Behaviour
    • The sound level meters in all three apps report suitable sound levels for me and the callers whose voices are being broadcast from the phone's speaker.
    • Suitable sound levels for the callers and me are achieved by carefully positioning the mic relative to the phone's speaker and my mouth.
    • During playback, my voice is crisp and clear, but the callers' voices are essentially inaudible, and during the very brief periods of time when the callers' voices were detectable, their speech was incomprehensible.




Click to expand...
teslapiphone said:
No, Google does not modify callers' voices broadcast from the Pixel's speaker to prevent recording by PC voice recorder apps. The voice transmission from a Pixel phone's speaker during a call is not altered or modified by Google to prevent recording. The audio output is typically the same as any other call made from a mobile phone.

The ability to record phone calls may vary depending on the specific phone model, operating system, and any additional apps or settings that are in use. In some cases, certain phone models or operating systems may have built-in call recording features, while others may require third-party apps to enable call recording.

It's worth noting that recording phone conversations without the consent of all parties involved may be subject to legal restrictions or requirements depending on the jurisdiction you are in. It is important to comply with applicable laws and regulations regarding call recording and respect the privacy rights of others.
Click to expand...
Ya Google works for the soon to be and new and improved (Loogle) $oon and compliance is com"ROD-ERY" (Evil Corp. is "Mevil" Corp.) And I have you all inside my MINDWAVE! HA, HA, HA!!! Let there be Go Go Loogle Spell correction automation for a creator!
 
Hadron said:
What magic signal do you think they are adding that allows the human ear to hear the voices normally but stymies mechanical recording? If they were outputting any additional sound within the audible range you would hear the distortion yourself. A signal at a different frequency would be ineffective (because it would not affect the frequencies of interest). For sure you could add noise that would make life difficult for a mic, relying on the human brain's pattern recognition abilities to let you understand what is being said, but if you did that the voice would definitely not be normal or clear to you.

If you have 2 speakers you can use interference (in the specific sense of interference of waves, not just the generic term "interference") to cancel out a sound in a particular location. But that only works if you have 2 speakers and some electronics which knows where they both are and where you want the sound to be cancelled, so that one can output an inverse waveform with the correct amplitude and phase offset to achieve the cancellation where you want it. If you try to put a destructive interference out through the single speaker you get no sound out at all (the 2 electrical signals sent to the speaker would cancel each other out and the speaker would not receive any signal at all, and hence output no sound whatsoever). There is no way that a single phone can do this.

If you were using a radio mic then you could imagine outputting a radio signal to jam its communications with the computer, but that would not affect just one side of the conversation. And I believe that's a USB mic, so we can dismiss that theory. Plus you need to be careful about using jammers in public places: even if you restrict them to the unlicensed radio bands (so that they are not illegal to operate), which you might guess is what a radio mic would use, they could easily affect other devices that use those bands (because you'd have to jam the entire band, not just a narrow channel, since you don't know which channel the radio mic is set to use). It would be a commercially risky move for Google to put something like that into a phone, as the potential downsides would way exceed any benefit.

Plus, on that last point, what would the commercial benefit of Google doing anything like this be? Google only gain from it if it increases sales, but it can't do that if it's an unadvertised, hidden feature.

My friend William of Occam suggests you look for a simpler explanation.
Click to expand...
Damn SMART ****IN KID I GOT HERE A!? Wow! Hadron, Sounds almost like an evolved being/living PC you are refering to here.
 
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