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Sm57 for vocals?

Hello, I have a cheap mic and what to get something to record vocals, drums, and maybe acoustic guitar. Would an sm57 do the job if I position it right and everything, or does anyone have other suggestions. Also the MXL 990 condenser seems good ( I do have phantom power) THanks


Pro Audio Guest Thu, 03/09/2006 - 00:38
I had always heard about it from other engineers who would say "modded" but wouldn't explain the process (I guess they thought it should be kept secret or something?). Basically, you remove the XLR connector, open the mic up, take the lower part (where the connector was) and dip it into boiling water to melt the glue, pull the transformer out, and green wire (+) from capsule connects to pin 2, and yellow to pin3 on the XLR.

I'm thinking about filling the shaft back with hot glue like it was originally, just to see if that really has much affect on the response (physics say they air inside the microphone behind the transducer can have an effect on response, just wondering if that is a significant enough volume of air).

Removing the transformer makes it even better for some applications due to more high and low end. The loss of 12dB of sensitivity also makes it better for high SPL applications. A modded SM57 can make a good inexpensive mic to use on a kick drum or toms. I still prefer a stock SM57 on snare because the hyped midrange helps out a little bit there.

If you do this, David, be sure to mark that microphone as modded, so you don't pick it up and wonder why it sounds different when you reach for a stock SM57.

I'm wondering how hard that shell would be to drill through so I could just add an in/out switch for the transformer. I'm not good with power tools, and I'm not sure I would even have the right bits.

Pro Audio Guest Mon, 12/04/2006 - 16:55
I wasn't sure about starting a new topic for something that I had already hit on, but I took the SM57 mod a step further this weekend. I took drilled a quarter inch hole in the side of the body and now have a short cable with an XLR connector sticking out of the side. Its wired before the transformer, so basically the mic now has a pre- and post-transformer out. I'll add a picture later if someone wants to see it.

David French Thu, 03/09/2006 - 08:44
That's an interesting idea, and they're cheap enough that you could try it with realtive impunity. You could always replace the thranny, too. But, I'm wondering, is the tranny really that bad? What if you replaced it with a better one. I wonder if there's a Jensen or something that would fit in there. Can you tell that I'm not an EE? :D

Pro Audio Guest Thu, 03/09/2006 - 09:01
I'm not an EE either, its just when posed a problem (or in this case, a mod), I like solving things. I understand how to make simple electronics like crossovers and direct boxes, but I'm still not an EE. I shouldn't have said POS on the tranny, because its not the worst. Its still not all that great though. I've kind of wondered if there is a better transformer that would fit in there. I've also thought about just housing a transformer in an external box with XLR connectors so I could basically have it inline. That might also help with the $10-$20 mics that are just crappy capsules wired directly to the XLR (Nady comes to mind). I'm no electrical engineer, but I love electrical experiments.

mark_van_j Wed, 12/06/2006 - 00:36
THAT would be very interesting to see! A short tutorial, (with pictures of course) would be a welcome addition. Even better, a youtube link! :)

On topic: I just did a session a couple of days back where we used a 57 on vocals. We compared it to a low budget condenser, a 58 and 57. The girl sounded best on the 57, espeically for the inde rock song that was recorded.

57 is the way to go!

Boswell Wed, 12/06/2006 - 03:57
Consider the SM57S, which has a SPST on-off switch that normally shorts out pins 2 and 3 on the XLR. The switch can be replaced by a DPDT switch to select transformer output or coil direct. It's important not to leave the transformer primary in circuit if you are taking the direct coil output. The direct output is 12dB lower than the transformer output, and needs a preamp that can treat it like a ribbon. Good quality cabling is also important.