Is Umik 2 required for some reason

[Harris48]

Hello. I want to do some scans of my room. I was looking into a mini DSP. I do a lot of recordings for business so I have active, passive, cardioid, super cardioid, and omni directional all types of mics most with XLR connections because all even half descent professional mics use XLR not USB. My mics cost 4 - 7 times more than the UMIK 2. So my question I had a call with this guy, self-proclaimed expert that sells gain matching services told me that the UMIK 2 was the best and absolutely required but this same guy didn't know what XLR or an audio processor even was so this makes me suspect of his "expertise". I'm new to the REW world but very knowledgeable about AV recording equipment, so good chance he could be right, but his presentation raised potential red flags for me. I just don't want waste money paying for an Uber when I already own a bunch of cars if know what I'm saying.

 

[JohnPM]

No, it isn't. Any half decent omni is fine, if you are going to scrutinise the high end response make sure the mic is flat at the top end, most have some variation or peaks above a few kHz.

 

[Deleted member 35357]

Maybe a calibration & a result file is all that is necessary for one of your mics?

Though I have no idea where you can get one done, or which mic would be advised for the task.

UMIK-2 is just you get a ready made package for ease of use and less hassles. You know it will work out of package.
I would dare say the UMIK products are more for home enthusiasts that know enough as a starter pack to get started. As their price isn't out of range.

How professionals work I have no idea, if it's good enough or is there better gear around I don't know yet. I just got started a few days ago with the UMIK-2.

I noticed quite a bit of internal electrical noise with my UMIK-2 connected to my PC as a home user.
50hz mains shows as a 65 SPL Peak with 25Hz & 100Hz having the same issue. Those peaks were in all my measurements showing through.

I don't know if other mics are diffrent (to new to this) but wasn't what I was expecting from this product when I noticed it was doing such a thing.
The source power of your connected device has an effect on how "clean" a signal you can measure. (or it is what is expected from the internal electronics?)

I thought professional gear shouldn't have such issues or do they use these mics with portable battery powered devices, and never noticed?

 

[Harris48]

No, it 't. Any half decent omni is fine, if you are going to scrutinise the high end response make sure the mic is flat at the top end, most have some variation or peaks above a few kHz.

@JohnPM Thanks! This is what youre talking about? So this particular mic wouldn't be good for this purpose?

 

[Harris48]

I went searching for similar measurements for the UMIK 2 and I came across this makes me second guess my previous comment

 

[Blumlein 88]

You can use published response specs to create a cal file for your omni microphone. I've done this for several microphones used in music and confirmed results with a calibrated Umik-1. They drop on top of each other when measuring a speaker if not perfectly certainly very, very close. Also most any omni needs no compensation at 2 khz and less.

I use an image of the published microphone response to apply to Web Plot Digitizer. From that you can create a CSV file which REW can use for a cal file. Watch the short tutorial video for Web Plot Digitizer and it is pretty easy to use.

 

[Blumlein 88]

Here is an example. Red is a Umik 1, blue is an Avantone CK-1 pencil condenser, and orange is a CAD M179 large diaphragm condenser in omni. Not perfect, but certainly usable. These were all measuring the same speaker in the same exact location. Some of the differences above 8 khz could be positional from inexact location on my part. I created a cal file for the two condensers using published response and Web Plot Digitizer.

 

[staticV3]

I went searching for similar measurements for the UMIK 2 and I came across this makes me second guess my previous comment

Here's one more: https://media.discordapp.net/attach...libration_Comparison-4x_foolhardy_Remacri.png
Both are 0deg compensation curves

 

[Harris48]

Great! Thanks everyone

 

[DVDdoug]

Another possible advantage to a USB measurement mic is that the dBSPL level is calibrated to the digital dB level. With an analog mic it depends on the mic sensitivity and preamp gain. But usually we are more concerned with frequency response and not so much the absolute SPL level.

Note that the measurement mic is individually calibrated. If you rely on published measurements from a different sample there will be variations. Maybe not significant differences but it's something to be aware of.

 

[Blumlein 88]

Another possible advantage to a USB measurement mic is that the dBSPL level is calibrated to the digital dB level. With an analog mic it depends on the mic sensitivity and preamp gain. But usually we are more concerned with frequency response and not so much the absolute SPL level.

Note that the measurement mic is individually calibrated. If you rely on published measurements from a different sample there will be variations. Maybe not significant differences but it's something to be aware of.

That is one of the things I like about the UMIK is you know what your dbSPL really is.

 

[Chrispy]

I remember when I first looked into a measurement mic and how to use a non-usb mic what with phantom voltage and setup it just seemed more work than it was worth, so went usb.

 

[Harris48]

I have/had the actual measurement from the mic I want to use but i cant find or threw them away cuz I never thought I would need them..haha

@DVDdoug

...USB measurement mic is that the dBSPL level is calibrated to the digital dB level

So I swear I'm not arguing with you just trying to learn here because I'm a complete noob to this measurement game and appreciate the advice. My understanding is that all mics are analog and the conversion to digital either takes place in the mic(USB) or in a dedicated audio processor. The mic takes in analog waves and has to have power to convert them into sound and digitalize that sound so that it can be recorded electronically. Isn't that like having to take an audio track from a movie and process the signal, amplify it and output it. You can have your TV do it all, an AVR/speakers, or pre/pro/speakers. Each producing better quality as you break up the task into individual components. Just because one does all the steps doesn't mean that they all dont happen so isn't it better to have higher quality components that specialize to do each step? Now as the saying goes the devil is in teh details and my analysis is super high level and can be extremely naive for this situation. @Chrispy I'm just starting to scratch that surface and figure out the time invested vs fun learning vs the $400 cost question.

PS I have no background in audio engineering but for work(and cuz I enjoy this stuff) I had to go super deep into setting up studio and other areas to get high quality recordings. I'm sure there are a million things I don't know.

 

[Harris48]

@Blumlein 88 Web Plot Digitizer is super cool! Mind blowing what people can make. I favorited it in case I have a use for it in the future too.

 

[Blumlein 88]

I have/had the actual measurement from the mic I want to use but i cant find or threw them away cuz I never thought I would need them..haha

@DVDdoug

So I swear I'm not arguing with you just trying to learn here because I'm a complete noob to this measurement game and appreciate the advice. My understanding is that all mics are analog and the conversion to digital either takes place in the mic(USB) or in a dedicated audio processor. The mic takes in analog waves and has to have power to convert them into sound and digitalize that sound so that it can be recorded electronically. Isn't that like having to take an audio track from a movie and process the signal, amplify it and output it. You can have your TV do it all, an AVR/speakers, or pre/pro/speakers. Each producing better quality as you break up the task into individual components. Just because one does all the steps doesn't mean that they all dont happen so isn't it better to have higher quality components that specialize to do each step? Now as the saying goes the devil is in teh details and my analysis is super high level and can be extremely naive for this situation. @Chrispy I'm just starting to scratch that surface and figure out the time invested vs fun learning vs the $400 cost question.

PS I have no background in audio engineering but for work(and cuz I enjoy this stuff) I had to go super deep into setting up studio and other areas to get high quality recordings. I'm sure there are a million things I don't know.

Okay so DVDdoug is letting you know something you may not have thought about. UMIK has an ADC converter built in and knowing the microphone can send a signal over USB so that REW knows the real db SPL you are getting. Your XLR microphones are analog and an audio interface will send the analog signal to an ADC to make it a digital signal. Fine and no problem. However the software has no inherent way to know how the signal level relates to actual db in Sound Pressure Level. or SPL. There are a few ways to calculate it or calibrate it or estimate it and get close. As long as you don't clip the ADC it usually makes no difference to you. You can calibrate a given XLR microphone to a given recording interface and gain level with a little effort or with not much effort if someone has Umik you can borrow to compare.

Oh, and Web Plot Digitizer is the fire for some purposes.

 

[Harris48]

Thanks...Exactly what I wanted to know! I'm going to get the UMIK and MiniDSP. Plus I always promise not to take anything from the the studio cuz each time I do it ends up taking me hours to get everything set up right again

I just hate buying things solely because it's what everyone buying

 

[kiwifi]

How long is that UMIK USB cable?

I use a Behringer ECM800O plus a Motu M4 interface and it works great. Using standard XLR microphone cables provides a more flexible solution in my opinion.

 

[kemmler3D]

this same guy didn't know what XLR or an audio processor even was so this makes me suspect of his "expertise"

Agree...

UMIK in particular is not required, it's just considered convenient because it comes with SPL calibration and you don't need an audio interface to use it. However like JohnPM said any omni measurement mic is good as long as you are confident in the FR and/or have a calibration file.

 

[Blumlein 88]

How long is that UMIK USB cable?

I use a Behringer ECM800O plus a Motu M4 interface and it works great. Using standard XLR microphone cables provides a more flexible solution in my opinion.

I have one of those 49 ft. (15 meter) USB active extension cables for my Umik1. Works just great. It is handy if you have long XLR cables as well.

 

[Berwhale]

I noticed quite a bit of internal electrical noise with my UMIK-2 connected to my PC as a home user.
50hz mains shows as a 65 SPL Peak with 25Hz & 100Hz having the same issue. Those peaks were in all my measurements showing through.

I don't know if other mics are diffrent (to new to this) but wasn't what I was expecting from this product when I noticed it was doing such a thing.
The source power of your connected device has an effect on how "clean" a signal you can measure. (or it is what is expected from the internal electronics?)

Maybe worth purchasing a cheap ADUM4160 based USB isolator to see if this solves the issue....

https://www.amazon.co.uk/Fasizi-Isolator-Eliminator-Industrial-Protection/dp/B09Z2CM1GS

Actually, you may need an isolator that is USB 2.0 High Speed capable like the Topping HS01...

Topping HS01 USB 2.0 High Speed Audio Isolator Compatible with PCM32bit 768kHz DSD512 Native Low Latency USB Isolator: Amazon.co.uk: Computers & Accessories

Topping HS01 USB 2.0 High Speed Audio Isolator Compatible with PCM32bit 768kHz DSD512 Native Low Latency USB Isolator: Amazon.co.uk: Computers & Accessories

www.amazon.co.uk