Behringer UM2 and dynamic microphones

[JacobFrånMinisteriet]

Hey all!

I have been recording for a while, even an album with my band (which is still in the mixing stage...), so I would say I have the basics down. However, I can not get any dynamic microphones to a usable output level with my Behringer UM2. I also use an sE electronics x1 (condenser, so it takes 48v) and that works perfectly, I am getting good levels with it. Further, I also have no problem running bass and electric guitar into the audio interface, they all produce good recording levels.

So my question is why it is almost impossible to get usable levels with the dynamic mics? I have recently bought an SL 75C by Behringer (sm57 copy) and have previously also used an sm58 copy by a different brand. Even with gain maxed out on the interface and gain boost plugins, I'm getting hardly usable levels, even when recording louder sources (guitar close-up and kick drum). I have read about the need for a preamp, but is the UM2 really too weak to get a normal dynamic mic to a usable level?

I hope this question is not too stupid and appreciate any help.

 

[Slouching Raymond]

I have phantom mics and dynamic mics plugged in to my pre-amps and they all seem ok.
It could be the UM2.
Has anybody in the band got something else like a mixer you could try them with?

 

[TalismanRich]

Condenser microphones have a preamp that boosts the signal, typically into the 10-20mV/94dB range. Dynamic mics have not such preamps (except for something like the SM7dB), using only the voltage created by the coil moving against the magnetic field. They typically are in the 1 - 2mV range.

If you preamp has enough usable gain, then you should be fine, but the UM2 doesn't specify available gain. I suspect it isn't very high. Reviews I saw say that they can be noisy at high gain levels. But you can't expect a dynamic mic to use the same knob setting as a condenser that is putting out 10 times more voltage.

They would work fine if you're hitting the mics with loud sources, like a guitar amp or a snare drum. Don't get out of sorts with having to turn the input knob higher. The critical thing to worry about is the signal level vs noise level.

An alternate approach is to add an inline preamp, such as the Cloudlifter, FETHead, KlarkTeknik CT1, or SE Dynamite. These are preamps, powered by your 48V phantom power, and provide about 20-25dB gain which should be plenty. That is the approach that Shure used to create the SM7dB.

 

[rob aylestone]

Almost all dynamics perk up at lot when an in-line preamp is used. Surprisingly so actually. Lots of dynamics traditionally got used at a distance from a speaking voice and early preamps were optimised for that and worked pretty well, but modern interfaces don’t perform well with gain set to 9 on a 1 to 10 scale. SM7B mics always seemed to be used with a preamp, but I tried AKG202 and 222 with the same preamp and was quite surprised.

 

[gecko zzed]

You aren't by any chance, connecting your dynamic mke via XLR to jack into channel 2?

 

[TalismanRich]

You aren't by any chance, connecting your dynamic mke via XLR to jack into channel 2?

Good point... the second input is for an instrument, which is going to be looking for a level much higher than a dynamic mic.

 

[JacobFrånMinisteriet]

You aren't by any chance, connecting your dynamic mke via XLR to jack into channel 2?

The UM2 has a combined XLR/6.3mm jack for input 1 which i was plugged into via an XLR to 6.3mm cable. I was under the impression that the preamp will be active nonetheless, but of course as @TalismanRich is rightly pointing out, that input is looking for a hotter signal. I have ordered an XLR to XLR cable which should show up today and I will try and see if that fixes my problem. Thank you to everybody for your advice, I will update in a few hours to report my findings.

 

[JacobFrånMinisteriet]

The UM2 has a combined XLR/6.3mm jack for input 1 which i was plugged into via an XLR to 6.3mm cable. I was under the impression that the preamp will be active nonetheless, but of course as @TalismanRich is rightly pointing out, that input is looking for a hotter signal. I have ordered an XLR to XLR cable which should show up today and I will try and see if that fixes my problem. Thank you to everybody for your advice, I will update in a few hours to report my findings.

As a little sidenote:

During the recording of the album, I was using the sE x1, plugged into input 1 via XLR and this other sm58 copy, which i was running via an XLR to 6.3mm cable into input 2. Because the levels from the sm58 copy were so low, I tried swapping the cables, meaning i was only running the sm58 into input 1 via XLR, but if I remember correctly, there was no noticeable change. I don't have that equipment where I am currently living, so I can't test it again, but it would be weird if this new dynamic mic works fine with an XLR to XLR. It's possible I left the 48v power on by accident and that caused some issues. As I said, I will report my findings and go from there.

 

[JacobFrånMinisteriet]

Hey all!

I have been recording for a while, even an album with my band (which is still in the mixing stage...), so I would say I have the basics down. However, I can not get any dynamic microphones to a usable output level with my Behringer UM2. I also use an sE electronics x1 (condenser, so it takes 48v) and that works perfectly, I am getting good levels with it. Further, I also have no problem running bass and electric guitar into the audio interface, they all produce good recording levels.

So my question is why it is almost impossible to get usable levels with the dynamic mics? I have recently bought an SL 75C by Behringer (sm57 copy) and have previously also used an sm58 copy by a different brand. Even with gain maxed out on the interface and gain boost plugins, I'm getting hardly usable levels, even when recording louder sources (guitar close-up and kick drum). I have read about the need for a preamp, but is the UM2 really too weak to get a normal dynamic mic to a usable level?

I hope this question is not too stupid and appreciate any help.

So it turns out plugging into the combined jack/XLR vie the 6.3mm option was the problem. It works perfectly fine now.

 

[TalismanRich]

That makes perfect sense.

The 6.3mm jack of input 1 is for a line level input which would be ~.3 to 1.4 volt. A dynamic mic signal is on the order of 1-2mV (1/1000 V). Instruments like a guitar or bass will be anywhere from 0.5V to 5V depending on if it is an passive or active pickup. The difference between a line input and an instrument input will be the impedance. A line level will generally be 10 to 50kΩ whereas a guitar input could be 500kΩ to 1MΩ.

As you do more study (and ask questions to resolve issues) you'll start to learn how different systems are set up. Even today, we learn things. There is a thread about a wireless system that gets overloaded with hot guitar pickups like on an Ibanez Jem, but work just fine with lower output pickups like a Stratocaster or Les Paul. Manufacturers are usually pretty good at stating relevant specs, but not always!