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slinkp slinkp is offline
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Default Does anybody sell pre-made resistor "gizmos" for sm57/58 mics?

On Tuesday, September 15, 2020 at 10:35:26 AM UTC-4, Mike Rivers wrote:
On 9/15/2020 10:12 AM, slinkp wrote:
I'd like to try the shunt resistor trick, as per eg. that old Paul Stamler article, but i have no idea where my soldering kit has got to, and exercising my soldering skills (terrible) is no longer on my list of "fun things to do
So if there's a place or person that sells eg. an XLR barrel with a suitable resistor already correctly wired into it, I'd happily buy one.

This isn't the sort of thing that becomes a commercial product, though
you might find some on this newsgroup or some other recording-related
forum who will volunteer to make one for you for cost and shipping.

I would, but I won't - because the 600 ohm resistor that Paul came up
with for his article was the best compromise, as evaluated by his
students, for the mic, preamp, and source. Different resistors sounded
different and may sound better than 600 ohms (or no resistor) on a
different source.

The other thing - and maybe now that I think about it, it might not be a
600 ohm resistor after all, but a different value - is that what they
really determined. This is the load on the microphone, which equals the
preamp's input impedance with a resistor in parallel that total 600
ohms. I may not have the number right, but that's the principle.

Paul conducted his experiment using a preamp that he designed and built
himself, so your preamp will be different.


Thanks for the thoughts, Mike!

It took some poking on archive.org but I found the article.
It was a UA 610 preamp, did he design those? (Honest question I have no idea)
Point taken anyway - I don't have one
https://web.archive.org/web/20171123...etail/330.html

He says "I chose 698 ohms as a good compromise resistor value that gives a total load of about 500 ohms (±10%) with common available preamp impedances from 1500€“2400 ohms. If you want to tailor the resistor to your preamp or boards actual value, see the sidebar" and then there's a section where he discusses the formula.

Apparently the 610 has a nominal input impedance of 2k according to the article. My Focusrite Scarlett 2i2 is even higher at 3k.
By his formula, 600 ohms would work for me: 1 / (1/500 - 1/3000) = 600

If you want to experiment with varying the load on a microphone, I'd
suggest that you give some consideration to buying a Cloudlifter Z. It's
a pre-preamp with a built-in variable load resistor. Even with the load
resistor switched out, the Cloudlifter will make your SM57 sound better,
and you can fiddle with the variable load to see how (and if) it affects
what you're recording.

https://www.cloudmicrophones.com/cloudlifter-cl-z

Unfortunately it costs about $250 new, but they're available on the used
market.


Those do look fun to play with. Thanks!