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Someone else posted that the standard issue items fall out of his ears. Mine too. and this is of course a problem when driving as you are constantly moving your head.
So I compared them with a good pair of Panasonic ones that don't fall out.
I think the problem is the width of the stem - it's at least twice as thick as the panasonic ones and therefore doesn't locate properly in the slot most of us have at the base of the earlobe. I think this is also why the sound is pretty crap compared to a good pair - they aren't close enough to the opening of the ear canal. If you apply very gentle pressure the improvement in bass is dramatic.
Anyway I also discovered that the mic/vol control/call switch thingy is a pop apart construction and anyone with some skill with a soldering iron ought to be able to solder a proper pair of buds in position. Unfortunately I don't have 'some skill with a soldering iron' so will have to find someone who does.
Why am I doing this I hear you ask ....'cos I'm peed off with blue tooth, in particular its mic pointing anywhere except where my voice is coming from. crappy mono sound ... no support for voice dialling, and constantly having to remember to charge up the bl**dy thing.
If I can get some decent buds on the standard kit, I'm then going to permanently remove the little rubber socket cover, work out a way of tidying the wires up (they seem to be made for someone with a head diameter the size of a very large beachball) .... then look for some way of activating the voice dialling via the two switches on the cable.
Mike
I was wondering if anyone knows how to raise the mic volume on a call. I use a car arm to use my phone to listen to music and answer calls while I'm driving. I've noticed that the mic volume is very low while the headphone jack is use (can't hardy hear me). Of I turn on the speaker feature on the call, the mic volume fixes itself. I was wondering is there was a way to raise the mic volume with the headphone jack in use .
Thanks in advance.
Bump!
Sent from my Nexus 4 using xda app-developers app
If you search for mic call on N4 threads you will see lots of complains and no answer. Seems like noise cancelation is the problem but still no luck
Stick your finger over the top microphone while you're talking. That will make the N4 send all the signal from the bottom microphone, effectively eliminating noise suppression but letting your voice come through okay.
wmm said:
Stick your finger over the top microphone while you're talking. That will make the N4 send all the signal from the bottom microphone, effectively eliminating noise suppression but letting your voice come through okay.
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Click to collapse
did it with no success, in fact that should be the solution for some reason it doesnt work for me
Dunno, then; I was just reporting the experience of a user in a different thread. I haven't had a phone call in the car since then, so I don't know whether it would work for me or not.
Just a thought -- my car mount has movable feet, and I have to make sure that one of them doesn't cover the microphone hole on the bottom. I don't know if your mount potentially has the same problem or not.
Can someone with an SPL meter help calibrate the Nexus4 for a sound meter app?
I like Sound Meter Lite but any free app from the Play Store will do.
Thanks in advance!
bump
Anyone? Any recording professionals out here?
This should not take more than 2 min of your time.
- Download a Sound Meter app from the Play Store.
- Play a tone through your speakers. Since phone microphones are mostly flat in the human speech region (300-3k Hz)
it is probably best to use a 1kHz tone.
- Hold an SPL meter aligned with the Nexus4 phone mic (located next to the microUSB port).
Make a note of the dB level on the SPL meter and the app.
- Report the app used and the dB difference between the app and the SPL meter in this thread.
First, are you sure the app is using the mic on the bottom as there is another on the top and it could even be utilizing both and even noise cancellation which would be bad.
Second, the mic on this phone has a very high sensitivity. I would guess the limit would be somewhere around 80db at which point it will start limiting and giving false readings. Pretty useless in and audio environment in that case.
Third, you would want to use pink noise to calibrate a spl meter. A sine wave is generally used to calibrate electrical components of audio (eg. dac).
smacksa said:
First, are you sure the app is using the mic on the bottom as there is another on the top and it could even be utilizing both and even noise cancellation which would be bad.
Second, the mic on this phone has a very high sensitivity. I would guess the limit would be somewhere around 80db at which point it will start limiting and giving false readings. Pretty useless in and audio environment in that case.
Third, you would want to use pink noise to calibrate a spl meter. A sine wave is generally used to calibrate electrical components of audio (eg. dac).
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Click to collapse
1. The Sound Meter Lite app shows a higher dB reading when I point the phone's bottom at the sound source.
Pointing the top (at the same distance) shows a few dB less so I think it's reasonable to assume that the main mic
is indeed at the bottom of the phone.
2. You are right about that. It's a limitation that I'm willing to overlook.
3. Pink noise is ideal.
A tone burst is only useful if one knows the mic's frequency response.
I asked for it because I will attempt to measure the FR on my own and post it here if I succeed.
I will take anything at this point.
I just started playing a few games on this Nexus 7, and I turned the volume down to the lowest setting because it is late at night and other people in my house are sleeping. I immediately noticed a soft but very audible static buzz coming from the speakers... about the same volume as the audio itself. I held my ear up to the hardware and confirmed it is both top and bottom speakers.
Anybody else experience this?
copyists sorpeno
I didn't notice at first. Noticed this morning with audio low as well.
I'd like to know if anyone else has this too. Kinda wanna know if its hardware since I purchased at best buy and only have 2 weeks to return.
Yup, I was going to report this too, but since it only occurs at minimal volume I didn't bother. I lost my good headphones so I can test the audio jack. Does it happen to you with them on too?
Btw- if this the trade off with the fantastic (for tablet speakers) surround sound I'll take it. Watch the test video on the Play Videos app.
Sent from my Nexus 7
I don't hear it. on mine. But My hearing is horked.
It's because the Nexus 7 uses a crappy digital volume control that simply reduces the volume of the digital waveform before it hits the DAC, instead of having a real analog volume control -an op-amp that adjusts the volume of the signal before it hits the headphone/speaker amplifier.
What you're hearing is quantization noise as at the lowest volume the audio uses only 2-4 bits of dynamic range instead of the full 16 (or 24, dunno what DAC is in this thing). It's the same as the bit-crushing effect you hear in some dubstep and other electronic music that degrades the audio into a robotic crunchy mess, only here it's not on purpose, it's just cheap design.
There is nothing you can do about it.
I've also noticed this (at first I was like, WTF? Is it raining in my game?). If what was said above is true, that makes me sad that nothing can be done about it.
siraltus said:
It's because the Nexus 7 uses a crappy digital volume control that simply reduces the volume of the digital waveform before it hits the DAC, instead of having a real analog volume control -an op-amp that adjusts the volume of the signal before it hits the headphone/speaker amplifier.
What you're hearing is quantization noise as at the lowest volume the audio uses only 2-4 bits of dynamic range instead of the full 16 (or 24, dunno what DAC is in this thing). It's the same as the bit-crushing effect you hear in some dubstep and other electronic music that degrades the audio into a robotic crunchy mess, only here it's not on purpose, it's just cheap design.
There is nothing you can do about it.
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I'm not sure how you know that but if you're right I guess that means it would happen on all of them... which.. sucks.. Is there anyone that doesn't have this issue to disprove this?
smurfqq said:
I'm not sure how you know that but if you're right I guess that means it would happen on all of them... which.. sucks.. Is there anyone that doesn't have this issue to disprove this?
Click to expand...
Click to collapse
I'm a professional audio engineer, I know exactly how these things work. Most cheap devices do volume controls that way, because adding a dedicated op-amp for analog volume control increases costs of the device, and the Nexus 7 is a budget device.
It does happen on mine, too, in every app that plays sound.
I love when pros come in here and give the technical explanation haha hats off to you, sir!
Sent from my Samsung Galaxy S4 using Tapatalk 4 Beta
siraltus said:
It's because the Nexus 7 uses a crappy digital volume control that simply reduces the volume of the digital waveform before it hits the DAC, instead of having a real analog volume control -an op-amp that adjusts the volume of the signal before it hits the headphone/speaker amplifier.
Click to expand...
Click to collapse
As the others have said, thanks for the explanation. Nice to hear from somebody who understands it, and if the problem is present in all units that actually makes me feel better since I don't have to worry about returning my otherwise perfect unit.
Question though, how come I don't hear the static when using headphones, even on the lowest volume settings where I hear the static from the built-in speakers? That makes me think it's related to the speakers and not the audio hardware... but you obviously know more than me on this.
mrmartin86 said:
I've also noticed this (at first I was like, WTF? Is it raining in my game?). If what was said above is true, that makes me sad that nothing can be done about it.
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Click to collapse
Yeah, funny thing is the first game I played was Bad Piggies on some levels with an ocean tide moving back and forth at the bottom of the screen. I thought the static was the tide sounds... until I heard it in another game too.
tweaked said:
I don't hear it. on mine. But My hearing is horked.
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Click to collapse
It only happens at the absolute lowest volume setting... i.e. one notch up from muted. It sort of happens at the next notch up too, but is most noticeable at the quietest setting, and you need to be in a quiet room. I only noticed because I was using the device in a small echoey mostly tile room (you can probably guess where) and because of the room having such acoustics I put the device on the lowest setting just above mute.
Had something like this on my original nexus 7
Except it happened regardless of the volume setting. Wasn't that audible- had to put my ear against the speaker to really hear it, but it did interfere with other devices, such as my radio, or keyboard with a head phone jack. It would make a sound like a quick DUH-DUH-DUH-DUH-DUH-DUH...DUH-DUH-DUH-DUH-DUH-DUH. My nexus 4 can sometimes cause static interference with other devices, too. Haven't gotten the new nexus 7 so I cannot say whether or not my new one has this issue
Well.. mine's not only happening at the lowest volume notch. If I put it to my ear (never actually going to do this for normal use) it's there at every volume level, just hard to hear once whatever I'm playing gets loud enough. The display unit at a local best buy does the same. I can hear it in a quiet room at the first couple notches (normal use), which is annoying. Also, since someone asked - No it doesn't happen through headphones.
The111 said:
As the others have said, thanks for the explanation. Nice to hear from somebody who understands it, and if the problem is present in all units that actually makes me feel better since I don't have to worry about returning my otherwise perfect unit.
Question though, how come I don't hear the static when using headphones, even on the lowest volume settings where I hear the static from the built-in speakers? That makes me think it's related to the speakers and not the audio hardware... but you obviously know more than me on this.
Click to expand...
Click to collapse
My pleasure! There's tons of FUD on XDA about many things, so I try to contribute on stuff I know well to reduce that.
Without looking at the schematics of the thing I can only guess:
The speaker amplifier is probably just a simple design that outputs 100% power all the time, so you have to control the volume of the signal that enters it, whereas the headphone amp probably has an integrated analog volume control.
A volume control is much easier (read: cheaper) to do in an integrated chip with low power signals (headphone out) than higher power (speaker out), and again, cheaper was the way to go with the Nexus 7.
Hence, there are two separate outputs from the audio chip - one that feeds the speaker amplifier and uses the bit-crushing digital volume control, the other outputs full-scale audio to the headphone amplifier which controls the volume in analog.
siraltus said:
My pleasure! There's tons of FUD on XDA about many things, so I try to contribute on stuff I know well to reduce that.
Without looking at the schematics of the thing I can only guess:
The speaker amplifier is probably just a simple design that outputs 100% power all the time, so you have to control the volume of the signal that enters it, whereas the headphone amp probably has an integrated analog volume control.
A volume control is much easier (read: cheaper) to do in an integrated chip with low power signals (headphone out) than higher power (speaker out), and again, cheaper was the way to go with the Nexus 7.
Hence, there are two separate outputs from the audio chip - one that feeds the speaker amplifier and uses the bit-crushing digital volume control, the other outputs full-scale audio to the headphone amplifier which controls the volume in analog.
Click to expand...
Click to collapse
Makes sense. Thanks again.
siraltus said:
My pleasure! There's tons of FUD on XDA about many things, so I try to contribute on stuff I know well to reduce that.
Without looking at the schematics of the thing I can only guess:
The speaker amplifier is probably just a simple design that outputs 100% power all the time, so you have to control the volume of the signal that enters it, whereas the headphone amp probably has an integrated analog volume control.
A volume control is much easier (read: cheaper) to do in an integrated chip with low power signals (headphone out) than higher power (speaker out), and again, cheaper was the way to go with the Nexus 7.
Hence, there are two separate outputs from the audio chip - one that feeds the speaker amplifier and uses the bit-crushing digital volume control, the other outputs full-scale audio to the headphone amplifier which controls the volume in analog.
Click to expand...
Click to collapse
Is this something they can fix (or at least mitigate) in a software update?
paxunix said:
Is this something they can fix (or at least mitigate) in a software update?
Click to expand...
Click to collapse
No, this is how the hardware is designed.
Noticed this too from the speakers regardless of volume, and regardless of what is playing audio. It's a high pitched squeal to my ears which I can't stand. I've thrown out computer power supplies and video cards that have made similar(obviously, louder) noises.
Was hoping it could be something improved in software, but I guess not. Time to sell this.
http://youtu.be/c9aQnuOrTY8
Recorded what it sounds like at lower volumes with a small condenser mic next to it. Let me know if that's similar to what you guys are hearing too.
Hi,
I'm trying to find a way to connect an external 3.5mm mic to my i9100 using a variable resistor (eg a volume controller in this case) to add impedance so that various mics with their different impedances can be connected freely, rather than just adding an inline resistor of arbitrary value.
A splitter like like could work perhaps:
http://www.ebay.co.uk/itm/310720331050?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
I was just checking out this thread for a similar hack:
http://forum.xda-developers.com/showthread.php?t=2072612&referrerid=0
and it says that impedance needs to be added in line with the mic so that the device recognises the mic as a mic (has to be above 1000 Ohms).
This has me wondering if, instead of adding a resistor in the cable that goes to the mic jack (or in the cable of the mic itself), it would be possible to use the splitting adapter above and plug a volume controller like the one below into the mic jack of the splitting adapter then the mic to the other end, like this:
http://1drv.ms/1c7ZwLY
Using the volume controller I can change the resistance between the tip connections of that cable, from 0 up to 1250 ohms, and then it jumps to infinity.
In the above photo the adapter is designed for nokias (OMTP) so the TRRS pinout is different to the i9100 (CTIA).
If I get a CTIA TRRS adapter, will I be abe to make this work using the volume controller?
This was fairly extensively covered in another thread.
My suggestion was just to capacitively couple the signal.
http://forum.xda-developers.com/showthread.php?p=49625339
Renate NST said:
This was fairly extensively covered in another thread.
My suggestion was just to capacitively couple the signal.
http://forum.xda-developers.com/showthread.php?p=49625339
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Click to collapse
I've read that thread and it doesn't say anything about using a variable resistor of some kind so that many mics can be made compatible, nor the general principle behind the idea (if it works etc).
Thanks for your suggestion about capacitive coupling, but at this point Id like to know if and how the idea I described could work. Your suggestion entails a mic mixer, an attenuator, and learning about capacitive coupling, and my idea just proposes using a volume controller, so Id like to know if the idea is possible before trying something more involved.
What kind of mic do you want to attach?
A regular computer electret mic with FET? Just connect it.
A low impedance dynamic mic? Use capacitive coupling.
A line level from something? Use capacitive coupling and an attentuator.
There's no reason to use a pot, you'd use a fixed resistor, but you don't even want that.
Renate NST said:
What kind of mic do you want to attach?
A regular computer electret mic with FET? Just connect it.
A low impedance dynamic mic? Use capacitive coupling.
A line level from something? Use capacitive coupling and an attentuator.
There's no reason to use a pot, you'd use a fixed resistor, but you don't even want that.
Click to expand...
Click to collapse
I'd like to use dynamic mics, but not just one dynamic mic, like the above thread and mod assumes. My idea is to use a volume controller to control impedance added instead of using just a resistor with a fixed impedance, so that the impedance could be matched to any dynamic mic and thus made to work (as each dynamic mic has its own impedance). This is the reason I had for the idea of a variable resistor of some kind; so that one mod could be adjusted using the volume controller for whatever the impedance is of the mic which is to be attached, and thus the minimum impedance could be added in order to make the mic work. Thus, you're not just stuck with using the mic which the mod (the added resistor) is designed to work. I hope I have explained the idea clearly.
According to the responses, the MOD in the above thread seems to work, and it entails getting less components and doing less research than your idea of using capacitive coupling, so Id be interested to know why you recommend using capacitive coupling instead of the above resistor MOD. Have you found the resistor method not to work very well? In your view is capacitive coupling the better solution for some reason(s)?
The first point is that the mic presence/button press detection circuit actually works on resistance, not impedance.
A nominal 150 ohm impedance dynamic mic has a DC resistance much lower.
Throwing an ohmmeter on my Shure SM58 I get about 17 ohms.
Any other mic can't be that much different.
To build that out to greater than 1k you're going to need a 1k resistance.
There's no particular point in using something variable for fixed duty.
Depending on the bias circuit inside the cell phone, the lower the resistance of the mic, the lower the effective resistance of the bias circuit.
This will reduce the level of your signal.
The series resistance will also reduce the level.
It's best to have infinite load resistance and zero series resistance.
Also, that way you are not wasting 1-2 mA of bias current.
I did a test using a 470 µF electrolytic capacitor and a Shure SM58 mic.
470 µF is kind of humongous, but a few calculations on input impedance shows that you need a decent value for bass.
I was amazed to see that the level in the stock "Sound Recorder was only about 6 dB lower than using the internal mic.
I'm pretty sure that there was at least 10dB of AGC coming in somewhere.
Renate NST said:
The first point is that the mic presence/button press detection circuit actually works on resistance, not impedance.
A nominal 150 ohm impedance dynamic mic has a DC resistance much lower.
Throwing an ohmmeter on my Shure SM58 I get about 17 ohms.
Any other mic can't be that much different.
To build that out to greater than 1k you're going to need a 1k resistance..
Click to expand...
Click to collapse
Ok, thanks....but now I'm lost. Your explanation seems to be at odds with the resistor mod explanation, where we are told that are options are:
1. Buy a microphone with over 1000 ohms of impedance.
2. Add some impedance.
Perhaps this is just a terminology problem though. The main problem for me, is that the formula given there to calculate the resistance / impedance (they seem to be used interchangeably in places )which needs to be added, in order to detect the mic, is:
"1100 ohms - (ohms of your microphone stated in the manual) = ohms of resistor required to turn on the microphone".
According to that post, we should get the value of the impedance/resistance from the value stated 'in the manual', which means would be using the value for the impedance stated in the manual, not actually measuring the DC resistance (which you have told us we should do, as it gives a very different value from the nominal impedance). Does this mean that the above post is wrong, and we should in fact be measuring the resistance using a multimeter, not just taking the value of the nominal impedance given in the manual?
No, really, just forget the resistor stuff.
A regular computer electret mic with FET? Just connect it.
A low impedance dynamic mic? Use capacitive coupling.
A line level from something? Use capacitive coupling and an attentuator.
Get an iRig Pre (which has a balanced input and a preamp).
Use a USB mic and USB host mode on your device.
Use a USB preamp/ADC/interface and USB host mode on your device.
Attached is a recording of quiet acoustic guitar using a Shure SM58, Alpha Lexicon and a Nook Touch.
Renate NST said:
No, really, just forget the resistor stuff.
Click to expand...
Click to collapse
Thanks for your suggestion to use the 'capacitive coupling' method Renate NST, but unless using it offers some advantage over the resistor method, I cant see any reason for using it. The resistor method is less costly, and requires fewer components and less research ( I know nothing about capacitive coupling).
Can someone confirm which of the above is correct? In order to calculate the resistance/impedance which needs to be added, should we use the impedance of a mic stated the mic's manual (as explained in the resistor method post), or use a directly measured value for resistance using a Multimeter (as Renate NST says above)?