SM57 to iPad without A/C adapter?

[ironcladlou]

Anybody have any strategies for getting an SM57 running into the iPad without any convoluted setups requiring an A/C adapter? I've been searching through the forums and haven't noticed anything for it specifically. I also need to preserve monitoring capability.

I COULD use my Tascam DP-008 into an iRig or something... Not sure how the noise of the iRig would affect the sound. Maybe through an AmpKit?

[Anorton]

http://forum.harmonicdog.com/viewtopic.php?f=2&t=6

After clicking the link, scroll down to the fourth picture.

I have this cable, and it works fine. There is a bit of crosstalk with my iPod touch; I haven't tested it on my iPad yet, but it should work the same.

[Erik dP]

As I wrote in the other thread (I use my solution with a radio for amplifying the earphones to elliminate the crosstalk):

I tried to connect a Shure SM57 dynamic mic using an AV-breakout cable from an old DV-cam. It has a "Ipod" headphone connector with four segments in one end, and three connectors in the other end (red + white +yellow). The red is connected to the two "mic connectors" of the ipod jack, i.e. 3rd and 4th segment counting from the tip. The other two is stereo headphone (tip and "next to tip" = R / L). All use common ground (the third segment from tip).

This breakout cable doesn't work by itself with the Ipod. I searched on the internet and couldn't find a solution. It seemed that Apple blocked third party michrophones (with later OS?). However, I found some info that there is ~ 2.8 V phantom power for a special kind of mic Apple use. With no proper mic detected phantom is turned off.

I guessed that this power also is used for actually measuring and detecting an Apple mic.

So. Instead for the SM57 I connected a 1kohm in its place, and this turned on the Ipod mic input. (I just guessed 1k as a saw something about the dock using this value to recognize the dock, or something like that).

I then removed the 1k ohm resistor and plugged in the SM57 which works fine with e.g. Amlitube. It seems like the mic detection is only done at the startup of the app. Now the phantom power is on.

I also read that 1 uF can be put serial to the mic, which I did. I guess that this could save some battery time in the Ipod. I don't know why else, or if the frequency respons in the low end would suffer. Anybody?

So my home made gadget:

1 kohm in parallell closest to the Ipod - with a on/off switch, as the sound seems a bit louder without 1kohm at operation.

1 uF i series with the mic, closest to the mic. Measure that the polarity is correct. I measured the common ground to be "-" (minus). So turn the "-" lable of the capacitor in this direction of the cord. It doesn't matter what side of the mic.

The usual disclamer:
Make this gadget on your own risk. Even though you won't blow up your Ipod/Iphone/Ipad you might hurt yourself or your equipment on the hot soldering iron.

[Anorton]

[quote="Erik dP"]As I wrote in the other thread (I use my solution with a radio for amplifying the earphones to elliminate the crosstalk):

I don't know what you mean by "radio". Would you explain a bit more about this solution? Thanks, and my apologies for not seeing what is probably obvious to everyone else.

[Erik dP]

...Well. You can use more or less anything that has an input for sound (AUX) and output (Phones) as an headphone amp. Or just use the built in speaker as a monitor.

For this I use a normal PAL radio from Tivoli Audio. But any stereo, ghetto-blaster, sound processor should work as long as it can amplify an audio signal. This audio signal should be the output from the Ipod/Iphone/Ipad.

Microphone/electric guitar -> Ipod/Iphone/Ipad (headphone in)

Ipod/Iphone/Ipad (headphone out) -> AUX IN on your radio -> Head Phones Out of your radio or other amplifying device.

By amplifying the signal outside the Ipod, the Ipod volume level can be kept low. A low enough level will minimize the crosstalk. Or rather: hide it further in the background so you cannot hear it.

[Anorton]

Thank you, sir!