Re: [LAU] General Audio question - soft recording and bad SNR?

Thanks Lens,

On Fri, Jul 18, 2014 at 1:22 PM, Len Ovens <len@email-addr-hidden> wrote:
> On Fri, 18 Jul 2014, Oon-Ee Ng wrote:
>
>> Hi, I'm running Arch Linux 64-bit with jack2. I have a USB UA-25EX to
>> which I connect a Shure SM75. I don't do much recording, and at a very
>> amateur level for various volunteer projects.
>
>
> SM75? or SM57? Everything I look up on sm75 turns out to be an sm57... So a
> dynamic mic. (Phantom off)

My typo, SM57 it is.
>
>
>> The maximum volume I get from my Shure SM75 seems very low. The result
>> of this is when I normalize I get fairly significant background hum.
>> Increasing the UA-25EX's gain just causes peaking at louder volumes,
>> so no solution there. This happens with both Audacity and Ardour, so
>> should not be software-related.
>>
>> Any suggestions as to what I should investigate? A bad mic (I did
>> check, its not a knock-off)? Electrical noise from my laptop (used to
>> use a different laptop but from the same manufacturer, same results
>> from both). Jack settings?
>
>
> I get that you did not buy this mic, but that it is whatever is around.
> There are a number of mics that look like the sm57. The only shure mic with
> a 75 is the pe75 (looks sm58 - ish) If you have a shure PE75H, it is a high
> impedance mic (30k plus) and probably comes with an xlr to 1/4 inch cable.
> If so, try pluging into input 2 and setting high impedance (HI-Z). Note: on
> this mic pin 2 is not connected, so using an xlr to xlr cable will not work
> right. (there is a PE75L that is properly connected inside the mic)

I did buy this mic, but that was a long time ago and as I mentioned, I
rarely record. It was just so I would have a mic when I needed one (as
opposed to the headphone-jack mics I was using prior to that.

Yes it comes with a XLR to 1/4 inch. I will try the Hi-Z and see if that helps.

>
> Please note that whatever mic you have, (PE75 or SM57) it is designed for
> close mic work, not for area mic use.
>
> You say the mic causes peaking at higher levels, yet I would suggest it
> needs to be almost to the top. The odd peak from touchong the mic or
> plosives is probably not a problem. (use the limiter provided - peak LED
> green) Use your ears above looking at flashing LEDs or even waveforms.

As soon as the peak LED activates I can audibly hear peaking,
unfortunately. I've tried the built-in limiter but it seems to produce
the same audible result (to my ears).
>
> As you may have guessed... I am mostly guessing :) we need to know what you
> are recording... how far from the mic, what are the settings on the
> UA-25EX... all of these things. As you can tell it even matters what kind of
> cable and which input you are using.

Thanks. This is a busy weekend for me, but I'll reply on these very
soon! Mic distance is anywhere between 2-6 inches from the (solo)
speaking voice beint recorded.
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Received on Fri Jul 18 12:15:01 2014