(update) I inadvertently said I got the 4 conductor plug at Jameco - it was Mouser, and is listed correctly, with the part number in the blog.Have you ever wanted to plug in a professional studio mic to your ipod touch/iphone? There may be a commercial solution, but I couldn't find one. Even if there is one, I figured I could build one cheaper than a ready-made one. You could also use this for a line-in (my original reason for the project), but the source really needs to be taken down to mic level from line level for good sound quality.
The hardest part was finding the 3.5 mm 4 conductor plug (found it at Mouser, #171-7435-EX). The soldering to the plug was a bit tricky too. I needed a cable with at least 4 conductors inside, and I wanted to build this for next-to-nothing, so I used some CAT5 ethernet cable I had. CAT5 has 8 conductors, so if you know of any other common cable with at least 4, you can use that.
I've included a rough wiring diagram below.
***UPDATE: Thanks to PTM for pointing out the ipod/iphone's audio input is meant for an electret mic. Therefore, there is 2.7 v across the input. However, there is only .73 mA of current. If this concerns you and you want to get in the habbit of doing it the right way, you should put a 1 - 10 uF cap like this one in-line to block the dc. If you don't know how or want to do this, the current probably won't do any damage, but be warned.***The sound quality with a Shure SM58 plugged into the ipod touch was way better than a very good pair of Shure earbuds/mic. When you look at the files in Sound Forge etc., the noise floor was about -60dB with the SM58 and about -50dB with the ear buds. The SM58 had way more dynamic range and obviously less background noise too. Not that surprising, since it's a professional mic, but more proves that for serious recording, this is well worth doing.
The earbuds/mic aren't terrible. It's more a question of "how good" do you need to get? On a pair of normal home computer speakers, there may not be as much of a difference, but I'm listening through a $1400 pair of Event studio monitors.
Here's the sound files to compare. They were recorded with the free Griffin iTalk app at 44.1k and file transferred directly via wifi :
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37 comments:
Any chance you can give the Jameco part numbers?
I did the same for a N95 to use a proper mic since the inbuilt one is worthless for making video with - I think the ground and mic connections were the other way around tho - Its not here to check but I toned out the supplied AV out cable to find which was the ground on it.
A Jameco part number would be excellent - I searched their catalog but couldn't turn up the appropriate plug.
I've tried using a 4-conductor "AV" cable but it doesn't work with the 2G iPod Touch. I ended up buying a Thumbtacks mic, but it has the disadvantage of not being able to plug in headphones while using it, so this would be excellent!
I've been searching for that plug forever! Please post the part!
What about USB cables? They got 4 wires, AFAIK, and you surely have a lot around your house.
There is a company making this adapter and also the opposite:
http://www.showmecables.com/viewItem.asp?idProduct=8335
Use you iPhone headset for Skype & other voip:
http://www.showmecables.com/viewItem.asp?idProduct=8183
Here is a 4 conductor 3.5mm male plug:
http://www.showmecables.com/viewItem.asp?idProduct=3099
4 conductor 3.5mm female jack:
http://www.showmecables.com/viewItem.asp?idProduct=4074
i've been trying to do this with my ipod nano, but apparently the apple earbuds whith microphone are the only ones able to manage this.. can anyone confirm this? and why do these little pushpin microphones do work? (google: thumbtack nano and you will find it) is there some special chip i'm missing? or impedance?
How well does the 3.5 mm 4 conductor plug fit into the port of the iphone? I have an edge phone, not the 3g, and there is a bezel/lip that got in the way of my using a Radioshack plug. I had a similar idea, I wanted to make an ear-free cable with a mic attached to my seatbelt and the output of the phone go Aux-into my car head unit.
I inadvertently said I got the 4 conductor plug at Jameco - it was Mouser, and is listed correctly, with the part number in the blog.
Telephone wire is 4 conductor.
Yay! thanks for the update Bent.
True. Just a tip though - I actually found it easier to use 5 conductors in the cable. Each jack needs a connection to ground, so I ran two ground wires from the plug. Otherwise you'll have to "Y" it somewhere, or daisy chain from one jack to the other.
This is a great tip. I happen to have a pair of my iPhone's original headphones around, and plan on using the cable from them, 4-C plug included. Now if only there were an app that would let you monitor while recording...
does this work with the first generation iPod touch?
"does this work with the first generation iPod touch?"
The electronics should work, it's a question of if that style plug will fit. Most likely not. You may need to incorporate J.'s idea-
"I happen to have a pair of my iPhone's original headphones around, and plan on using the cable from them, 4-C plug included."
I tried this. The iPod however expects an electret mic. So, there is some current flowing through the SM58. I think this may be harmful, so I tried several things with capacitors, resistors etc., although with no succes. Any thoughts about this?
I would be really surprised if a mic as robust as a 58 would be harmed with a little bit of charge. Thoughts?
Researching......
Another thing I tried to do was trimming the input of the mic with a trim-pot. The iPod does not respond very well to this. It just won't see a microphone (or headset) and gives an error. This even happens when the pot is at 0 ohm, I think because there is still a resistance on the earth line. Can anyone think of a solution for this, for it might be very handy when trying to record from a loud sound source.
See original blog entry for capacitor update.
I've got a cheap dynamic mic to work as in input to my iPhone which is working great. I also wanted to be able to trim the volume but trim pot didn't work for me either.
any good ideas about a passive volume control?
Has anyone tried this adapter from ShowMeCables? I'd rather not source the parts and build it if I could just buy it.
http://www.showmecables.com/viewItem.asp?idProduct=8335
Thanks for this post, was using my multimeter and a tone generator I could switch left/right audio on to try and figure out what was what, but this helped more since I had not taken into consideration there being voltage on the mic. Luckily the mic im gonna use is a Electret mic, so don't need to go back to Radio Shack for anything else, just finish soldering the wires together.
frack, frell, drokle, smegin, dren. Got it working, then two of the wires broke cause I used a knife to strip the insulation since I couldn't find my wire strippers. Oh well, have to find them.
I made this cable to plug my guitar into my iPod, but there is an impedance mismatch and the iPod doesn't recognize the guitar. (Guitars are high impedance and the iPod is low impedance).
Peterson makes this cable:
http://www.petersontuners.com/index.cfm?category=150
But it doesn't give you access to heaphones.
Can anyone help me out with this?
This is fantastic,..and I think it is what I've been searching high and low for to enable me to use high quality mics for recording onto my ipod touch. Now is it possible to record and listen at the same time with this?
Yup, it splits into two sockets, one for the mic and one for headphones
Have I missed something? Nobody has pointed out the "obvious" simplification of just picking up and modding a TRRS to component cable like this one:
TRRS to RCA
Then all you have to do is buy two easily-acquired 3.5mm females and attach. You don't even need to bother with finding a mono female -- go ahead and just wire up the tip and the sleeve, it is electrically the same as a mono female jack, just a smaller but adequate conductive surface for the ground.
I have assembled the parts for this but my soldering kit is in another country, I'll have to buy one and do the soldering before I can report on success.
The capacitor is more or less unnecessary -- most microphones can deal with upwards of 48V (phantom power) being mistakenly applied, since this happens pretty regularly. Just don't hook up your precious ribbon mic to your iPhone!! :-D
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hey I'm curious how Marc's cool idea turned out?! please explain your make up on this project and how it ended up working for you
I can't say I have ever wanted to plug in a professional recording decive in my ipod touch, but I have seen a store that sells professional hand grips for video recording for iphone 3gs lol
@Marc- Yes, I used that setup before I did this project. But, none of my connections were RCA (so I had to use adapters) and I wanted something short, not a long cable. But yes, you are correct - an A/V cable will work (although, then you still have the DC current to deal with)
Right, you can cut the A/V cable as short as you like since you are stripping the wire and still soldering on the 2 females.
Likewise if you are concerned about the DC (which isn't going to hurt anything except a fragile ribbon, and helps you if you want to connect an electret), you can also put a cap in there somewhere when you are cutting it open.
Touche! :) And I thought about that at the time, however, I only have one of those a/v cables, and I use it for another device, and I got the parts for this breakout cable for cheaper than buying another a/v cable. (and I just wanted to build it from scratch). But, If someone had an extra one laying around, sure!
I wonder how can you make this cardioid mic working? I've tried on an iPhone 3Gs with a cheap external electret mic, it is working perfeclty but it's a no go with my Shure Beta 58A... Any trick?
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