[Dr.Cmnsky]

Hello all.  I wanted to know exactly what I need to buy in order to measure my speaker's response in-room? I'm talking any adapters, cables, splitters, pre amps, usb sound cards, mics, etc.  I've reviewed several guides and they were a bit confusing. I dont want to spend a fortune! Please advise... Thanks!

[JLM]

Do you really want to know?  (You may not like the answer or the solution.)   

Behringer DEQ2496 with microphone is the non-PC method to test and provide 31 frequency bands of equalization (but careful you should avoid adding much gain).  Lots of folks should chime in on software methods, especially from the AV world.

Bass/mid-bass (below 300 Hz) is typically the biggest issue.  The best answer is to use 3 or 4 subs.  Check out the AudioKinesis circle (under the circles tab) as a good example.  Many will try EQ (but that should be the last step) or treatments (that should be the 3rd step) but the multiple subs approach (other than avoiding cubic rooms) should be your first solution (but it cost $$$).

[Dr.Cmnsky]

Well, I'm looking to turn my laptop into a speaker output measuring device. I'd like to perform sweeps to identify the differences if any for changing speakers or adding room treatments.

[kc8apf]

I read a lot of those guides as well.  I finally settled on the following hardware:
http://www.m-audio.com/products/en_us/MobilePre.html
http://www.cross-spectrum.com/measurement/calibrated_cm140.html

I also picked up a cable to do an external loopback (output connected to input) so I could cancel out the effects of the MobilePre.  Cross spectrum also sells calibrated mics which you'll need if you plan to do anything higher than ~250Hz.  For the software side of things, REW works well for measuring room effects and should do a decent job at higher frequency analysis.

[SoCalWJS]

I decided against doing the REW method in order to avoid all the problems(cords, sound card, Rat Shack Meter inaccuracies), and bought the OmniMic. A bit of $$, but an all in one solution that is easy to use to get the answers you need.

Pretty content with the results (just be prepared to get sick of the test tones and the constant feeling that if you move the speakers just a little bit more, the FR will be smoother )

[MaxCast]

Here is a good read from HiFizine

http://www.hifizine.com/2011/06/bass-integration-guide-part-1/

[JohnR]

I decided against doing the REW method in order to avoid all the problems(cords, sound card, Rat Shack Meter inaccuracies),

None of those are a REW issue...

[sts9fan]

I went the MobilePre Cross Spectrum route. REW is a great program. 
I have not used the OmniMic but I doubt it is better. 

[Ethan Winer]

I wanted to know exactly what I need to buy in order to measure my speaker's response in-room?

The freeware REW software with a $50 Behringer or Nady microphone and USB sound card with phantom (microphone) power is all you need to do a complete analysis. Full details here:

Room Measuring Primer

--Ethan

[Dr.Cmnsky]

I'm lookin' on Amazon and about to order the following:

M-Audio MobilePre - M-Audio
Behringer ECM8000 Condenser Ultra-Linear Measurement Condenser Microphone

The total is about $168.

Does this sound about right?

[randytsuch]

I spent a little more on the mic, to get a calibrated one.

I bought this one
http://www.cross-spectrum.com/measurement/calibrated_dayton.html

but they also sell calibrated Behringers.

Note that calibrated means that you get a file that can be used to correct the measured data.  Using the correction data should get you basically flat frequency response.

Randy

[Dr.Cmnsky]

I see - Thanks. I take it that the calibration is essential?  Ack - Disregard my previous response. I'm going to get that one.

[Dr.Cmnsky]

I purchased the following:

Microphone
Calibrated Dayton EMM-6
http://www.cross-spectrum.com/measurement/calibrated_dayton.html

Would the  ART USB Dual Pre work for this purpose? It's pretty cheap.
http://www.amazon.com/gp/product/B002KEAT78/ref=oh_details_o01_s00_i00

and a 25 foot XLR cable.

[JohnR]

Good call on the calibrated mic from Herb

The ART should work, but see this and also search for it with "Room EQ Wizard" to see if people are having success (a quick look shows a lot of threads on HTS). The "mix" knob will need to be all the way to the right I suspect.

FWIW I'm doing a roundup of some measurement gear for September HifiZine



 http://johnr.hifizine.com/2012/07/10/measurement-roundup/

[Dr.Cmnsky]

Thats great. There are far too many poorly written articles out there!

[poseidonsvoice]

http://seriousaudioblog.blogspot.com/2012/04/should-you-get-your-measurement.html

Anand.

[JohnR]

Thats great. There are far too many poorly written articles out there!

Thanks for the vote of confidence I've decided to structure it as a series of reviews of each item, as doing complete tutorials will be too time-consuming, esp. if it has to be done for two platforms.

With some initial test done, I'm impressed by the Focusrite Scarlett 2i2. Here are the loopback responses for 44.1, 48, and 96 kHz sample rates. At 96 kHz, it's basically ruler flat from 10 Hz to 40 kHz.



The MOTU and the Focusrite are two completely different types of unit. I didn't realize it when I bought them... so long ago, like yesterday? As usual, you can't have your fish and your kettle in the same pot at the same time.

[Dr.Cmnsky]

So, I've purchased the

ART USB Dual Pre ($75)
Calibrated Mic
XLR 25 ft Cable

I already have a Boomstand, but threw out the microphone adapter.

Does anyone know what adapter/holder I need to  buy?

and finally - what other cables am I missing?

[JohnR]

The mic comes with a mic holder with a removable insert to adapt to 1/4 or 1/2 inch stands. So you should be right there.

I would suggest a 4m USB (type A - type B) cable. That is unless you want to buy long RCA leads. But you can get the USB for about $5 on ebay.

You will need adapters to get the output of the interface into your system. From the looks of it, a pair of 1/4 inch to RCA adapters will do the trick. But check the manual to make sure that they don't mind having unbalanced 1/4 inch jacks plugged into them.

Finally you will want a loopback cable for calibration. Something to plug the output right back into the input.

[Dr.Cmnsky]

Awesome. I plan on using my desktop (which is about 15ft away from the LP).

So I'll go with:

Dual 1/4 to RCA  ($9)
http://www.amazon.com/Hosa-Cable-CPR204-Dual-Inch/dp/B000068O19/ref=sr_1_3?ie=UTF8&qid=1342014132

13 ft + possibly a smaller 5ft adapter.

Would that work or should I pay $20+ for the 20ft cable?

Thanks for all of the help