Record from line out from mixer on my android phone ???

T

techspark

Member
I have a galaxy s4 and i m planning on buying a adapter like the irig for iphone
http://www.ebay.com/itm/iRig-Guitar...ablet_eReader_Accessories&hash=item4178baac14


or this one
http://www.ebay.com/itm/300928487833


Basically these adapters will allow me to attach an external mic or line input on my S4's headset jack and i will be able to record through third party apps available on play store but the issue is i m not sure if this will work well.


I want to record some music from local event and take line out from the mixer from the headphone out port (150 mV at 8ohms THD <1% as per the manual of the mixer that we use here) and feed this to the irig adapter and record on my S4.
Or should i use tape out ports (250 mV RMS /600 ohms)


I really don't understand the above numbers, i just want to make sure the recordings wont be clipped.


Will this work ?? Will the recordings be clean (i know the quality will be just ok as it is only mono audio but i do not want recordings to be distorted or clipped)




Please let me know , thanks :)
 
So while there's no hardware on the phone that's going to make your sound better (pre-amps), that setup depends also on your mixing app never crashing. I admit I'm still in the dark about what pre-amps actually are but apps crash on my phone all the time.
 
I had a reporter friend that used his phone for recording press conferences..... UNTILL he found out it drops out of record when someone calls that number (despite his phone on silent).... I can't remember the brand tho.
 
It's hard to say if it will work without doing tests. I can't find any input statistics of the phone, but I doubt that it will take any line signal without a pad. Connecting it to the headphone out of the mixer might be ok, as you can control the level so it doesn't clip.

Regarding the call problem - just put it in flight mode.

Might work, but I think it seems very unstable. I would buy or borrow a cheap handheld recorder like the zoom H1. If you buy it and find no need for it afterwards (though I always find uses for mine, like recording lectures) then you can sell it at very little or no loss.
 
The phone is expecting a very low powered mic-level input, so you have to be very careful with this. Those adapters mentioned above are for unpowered mics, so an amplified signal from a mixer could not only clip and distort, but could actually burn out the hardware inside your phone.

PROCEED WITH EXTREME CAUTION!

If you *really* don't have a dedicated recorder or camera to plug it into, and can't borrow or rent one, I'd start it off at the lowest setting and monitor with headphones. Get a recording app that shows live levels, and carefully adjust it until you find the sweet spot between separation from the noise floor and safety from clipping. Obviously you don't want it to get high enough that it could clip/burn, but since the preamp on your phone isn't going to be very good, recording too low is going to bring more background hiss and noise with it. It's tough to find that happy medium with such limited range devices, but it is possible.

Also, get insurance on your phone plan first. :)
 
Phones are phones. I would never advise anyone to record anything important to it. There are plenty of lower budget audio recorders out there that can do the job just fine.
 
Thank you guys for all the replies and yes all of you are right , the phone is not suited for this purpose and i just did a couple of tests and found out it would not work :( Here are some tests that i did.

I bought a 3.5mm to 3rca(red,yellow,white) wire. The red wire corresponds to mic input terminal and i tried connecting the red rca wire to the audio out of my TV's set top box and voila it worked. I could record line in audio from my set top box on my s4 without any distortion but when i tried the same red wire on the rca tape out port of the mixer that the dj guys use here, my s4 does not detect it as an external mic is connected, instead it records from the inbuilt mic.

To test further i tried to took sound out from my laptop's headphone port and used a 3.5mm to rca convertor and again my S4 failed to detect that an external mic is plugged
frown.gif


So yes i think the phone is expecting only a very low level signal and when it gets the signal it shows as mic is plugged but when it does not then it simply uses the inbuilt mic :(
 
techspark said:
Thank you guys for all the replies and yes all of you are right , the phone is not suited for this purpose and i just did a couple of tests and found out it would not work :( Here are some tests that i did.

I bought a 3.5mm to 3rca(red,yellow,white) wire. The red wire corresponds to mic input terminal and i tried connecting the red rca wire to the audio out of my TV's set top box and voila it worked. I could record line in audio from my set top box on my s4 without any distortion but when i tried the same red wire on the rca tape out port of the mixer that the dj guys use here, my s4 does not detect it as an external mic is connected, instead it records from the inbuilt mic.

To test further i tried to took sound out from my laptop's headphone port and used a 3.5mm to rca convertor and again my S4 failed to detect that an external mic is plugged
frown.gif


So yes i think the phone is expecting only a very low level signal and when it gets the signal it shows as mic is plugged but when it does not then it simply uses the inbuilt mic :(
Click to expand...

Well that's strange. That's actually not at all what I expected to happen- I figured the sound would record but be totally blown out and unusable (or worse, fry the amp on your phone). What I didn't expect is for it to give up and use the internal mic. That actually doesn't make sense to me based on my understanding of the equipment- I'm under the impression that the phone doesn't have a way to detect what's plugged into the RCA jack once the 3.5mm adapter is in.

The phone detects if a pair of headphones is in via a physical button inside the jack that gets pressed when the plug is inserted. If you were to rip the plug off a pair of headphones and plug it in, it would still detect something is there (even though there is nothing attached on the other end) and silence the internal speaker. In fact, I've seen people carry a severed headphone plug in their pocket as a "mute all button" for apps that still play sounds even when the phone is on vibrate.
As I understand it, the phone knows if there is also a mic by the size of the plug (if mic is present, the plug is a bit larger to accommodate the extra pin). If there is no mic pin detected, it reverts to the internal mic. So as far as I know, once you insert an adapter that has all the pins, the phone will think headphones and a mic are present and shut off the internal mic whether anything is plugged into the end of the adapter or not!

Was the same adapter used in all 3 scenarios? If so, I'm going to guess the following:
1) the adapter was not inserted all the way the other 2 times (I have used an adapter like that for hooking my phone up , and it thinks it is only stereo unless I push it in hard to see the other pin)
or
2) the adapter needs all three lines to be active to work. When you hooked it up to your TV, did you also plug in the other two channels ie yellow and white? This one is a bit more complicated to explain as I don't fully understand it myself, but I think it has something to do with the ground loop needing to be closed. That's the outside of the RCA pins, I think. My electrical engineering is rusty, but I have noticed that sometimes an RCA out to a monitor (such as back in the days of standard def video monitors) there were times that if I unplugged one of the composite jacks, the rest of the connection went haywire with it.

Still, at the end of the day, even if you get this to work I think it'll be a lousy recorder. But for the sake of science, I want to point out that it SHOULD/COULD work.
 
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Most of the phones use a TRRS jack and you can use an AV cable as the OP has tried but I understood that the red and black were the audio outs and the yellow was the mic input.

You can also make up a cable as I have done with XLR connectors on:


The IFB XLR is the left and right headphone output and can drive an IFB amp or a set of headphones with an adaptor.

The MIC XLR needs a dynamic mic plugged in as it is the impedance of the microphone that switches the phone from internal to external, you can also use a high impedance to low impedance transformer and a 30db pad to allow an line input to feed the mic input.

Note I do not use this to record with the phone as it is not suitable for all the reasons already given but I do use this cable for coms set-ups or to feed an earpiece in an emergency for live TV stand ups.

I bought the moulded TRRS cable from e-bay and cut it in two then soldered the XLR's on giving me two half metre cables: http://www.ebay.co.uk/itm/3-5mm-4-P...ion_Audio_Cables_Adapters&hash=item35bfe85fbb
 
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GaryNattrass said:
Most of the phones use a TRRS jack and you can use an AV cable as the OP has tried but I understood that the red and black were the audio outs and the yellow was the mic input.

You can also make up a cable as I have done with XLR connectors on:


The IFB XLR is the left and right headphone output and can drive an IFB amp or a set of headphones with an adaptor.

The MIC XLR needs a dynamic mic plugged in as it is the impedance of the microphone that switches the phone from internal to external, you can also use a high impedance to low impedance transformer and a 30db pad to allow an line input to feed the mic input.

Note I do not use this to record with the phone as it is not suitable for all the reasons already given but I do use this cable for coms set-ups or to feed an earpiece in an emergency for live TV stand ups.

I bought the moulded TRRS cable from e-bay and cut it in two then soldered the XLR's on giving me two half metre cables: http://www.ebay.co.uk/itm/3-5mm-4-P...ion_Audio_Cables_Adapters&hash=item35bfe85fbb
Click to expand...

Ah, so the mic is detected by impedance on the line? I did not know that- very interesting. I assumed it was triggered by a switch the same way the headphone jack is actuated. I guess that makes more sense, as I wasn't sure the extra pin actually made the plug longer or not.

So the question is, why did the TV connection work but not the mixer?
 
I think you've gotten lots of info on will it work or not but the bigger question of recording a boad mix is, should you? Here's how I determine when I should record a board mix or use room mics, or even a zoom.

1. Is there any acoustic energy coming from the stage that the FOH mixer is using as a primary (or even complimentary) source to the house mix? This is typically the case in less than 1000 seat venues. If so, then the board mix will not be a proper representation of what the audience is hearing. It would make more sense to have a few mics placed (possibly overhead) right in front of stage and capture that to mix with a signal from the board. Also note that a headphone feed is not a good idea in that the house mixer may well solo instruments during the performance to check on this and that will totally whack your recording. Better to get a tap from his main left/right. Aux sends will only work if the send is configured as a post fader send. This is not always the case so best to check.

Board feeds will not grab much of the audience which may or may not be good. Larger shows have a few crowd mics positioned on the wings of the stage, pointed at the audience and are used to feed the performer's in-ears, providing the performer with audience feedback which can be a problem with in-ears.

How big is the show and how much access you have will help determine the best way to record.
 
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