# M-Audio Fast Track Calibration on Mac



## Cizonor (May 15, 2011)

I am new to REW, and am running into some issues calibrating my soundcard, a M-Audio Fast Track. I am concerned that my output signal is running through my input and back out the same output, creating a loop. I am using a Mac, and I can't locate a way to keep the mic input signal from looping back out the output. Any ideas? 

Thank ypu!


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## EarlK (Jan 1, 2010)

Hi,



> I am new to REW, and am running into some issues calibrating my soundcard, a M-Audio Fast Track. I am concerned that my output signal is running through my input and back out the same output, creating a loop. I am using a Mac, and I can't locate a way to keep the mic input signal from looping back out the output. Any ideas?



- Turn *off* the "Direct Monitoring" on the "Fast Track" soundcard ( button #5 = *OUT* ) .










<> EarlK


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## EarlK (Jan 1, 2010)

> ,,,,snip,,,I am concerned that my output signal is running through my input and back out the same output, creating a loop.,,,,,snip,,,,,


Alternately, if you're using the original Fast Track (USB), turn the *Mix Control* (#4) all the way to the right ( fully clock-wise ) . 









<> EarlK


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## Cizonor (May 15, 2011)

Earl,

Thank you for your reply. It appears that as long as the direct monitor button is off (not depressed) there should not be a loop. 

Here is the measurement I am getting. Not the flat line I was hoping for. Any more thoughts? Thanks so much.

48K










44K


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## Cizonor (May 15, 2011)

Still working on posting pics, haha.

http://www.flickr.com/photos/[email protected]/5741740907/

http://www.flickr.com/photos/[email protected]/5741740907/


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## EarlK (Jan 1, 2010)

The Mac computer can itself create audio loops ( which cause feedback problems ) .

I don't have a modern MAC here ( or else I'd post my own screen shots of what to do to help guide you properly with this next bit of advice ) ; 

Here's one screen-shot ( *taken from here !* ) ;










- If ( for some reason ) the "thru" box was checked in the above pic / one would create a feedback loop of input to output ( & on & on ) .

- Also make sure your Macs builtin microphone is not choosen as the "default" input ( or mute it ).










- Obviously, if this "*Audio MIDI setup*" utility is "news to you" ( as it is to many ), then go find where it is on your Mac , open it up & play around with its settings ( to stop sending input to output ) .

<> EarlK


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## Cizonor (May 15, 2011)

Earl,

The MIDI setup interface was a great idea, but unfortunately, it has not resolved my poor measurements. I muted all of the inputs/outputs except for the M-Audio Fast Track input/outputs, and still no luck. I even tried running an output from the computer's headphone jack to the M-Audio input to see if that made a difference, and the measurement is consistently inconsistent between 20 and 600 hz. 

I am running out of ideas...

Does anyone know of a usb soundcard that plays well with Macs & REW???


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## EarlK (Jan 1, 2010)

> snip,,,,,I even tried running an output from the computer's headphone jack to the M-Audio input to see if that made a difference, and the measurement is consistently inconsistent between 20 and 600 hz. .....snip


- Hopefully that was done using a proper stereo splitter cable ( at the Mac end ) .

- Also go back to all the audio control panels that allow the user to set the sampling rate / then set them all to 44.1K , 16 bit ( and once again, try a calibration ) . 

- Failingly that, ( as a reality test ) see if you can get a good calibration of your Macs internal sound card .

<> EarlK

ps ; What Mac are you using and what OSX version is it running ?


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## Cizonor (May 15, 2011)

Hi Earl,

Thanks again for your help. I used the proper splitting cable, I set everything to 44.1K/16bit, and same measurement.

So I measured the internal sound card - exact same measurement!

http://www.flickr.com/photos/[email protected]/5744764050/

I am using a 2010 IMac running 10.6.7.

???


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## JohnM (Apr 11, 2006)

When you make a loopback measurement go to the Scope graph and see what the captured input signal actually looked like, post a screenshot of that if possible. What input levels does REW show when you play a test signal (with the loopback connected)?


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## EarlK (Jan 1, 2010)

EarlK said:


> - Failingly that, ( as a reality test ) see if you can get a good calibration of your Macs internal sound card .
> 
> 
> 
> ...


- Well, that reality test suggests that the problem is not your M-Audio Sound-Card ( unless you complicated things by leaving it plugged in while running the internal S-C test ) .

*Okay , last kick at the can ( I'm out of ideas now ) ;*

- Get into the preferences area of your "iChat" program and then either mute or disable ( any or all of) its' sound functions .

- Do the same with "Skype" ( if you happen to have it loaded on your machine ) and any other sound producing software .

*Observation :*
- All your attempts at Calibration ( to my eyes ) appear to have the trace of another sound source mixed in ( albiet out-of-phase ) with the loopback trace. 

*Hand-Off :*
FYI, JohnM is the author of REW, so I will now leave you in his capable hands .

<. EarlK

PS : Here's your "Scope Graph" for JohnM to review ;


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## Cizonor (May 15, 2011)

Gentlemen,

Thanks for your ideas. It is awesome to be able to get a dialogue on this. My wife just doesn't get my frustration, haha. So I disabled ichat and skype and still no luck. The scope is below:

http://www.flickr.com/photos/[email protected]/5749505332/

I also plugged the Fast Track into a Microsoft computer at work today and got a ruler flat line, so it is definitely not the Fast Track.

http://www.flickr.com/photos/[email protected]/5748958787/

Any more thoughts???


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## Cizonor (May 15, 2011)

One more thought, the only difference I noticed between measuring the Fast Track on the PC versus the Mac (besides the ruler flat frequency response) is that the REW preferences on the PC allowed me to select the Fast Track as an input and output device, whereas the REW preferences on the Mac only allows me to select the "default device" output and Fast Track input. Of course, I have the default device on the Mac set to Fast Track input and output, and I know that the test signal is playing through the output on the Fast Track, so probably not the issue, but in the interest of full disclosure, there you have it.


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## Cizonor (May 15, 2011)

Levels: -12 db output and input


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## EarlK (Jan 1, 2010)

Cizonor, I'm out of ideas for the moment *( edit : see below )* / especially since you were unable to successfully calibrate the built-in Mac soundcard on your iMac .

FWIW, this is the first time that I've been made aware, that REW won't "play nice" with a built-in SC on a modern Mac . That is truly baffling .

Therefore, I'd ( first ) concentrate on getting the built-in card calibrated / & then move-on to the M-Audio once successful . 

While I run a PC ( XP-Pro , SP3 ) here at home / I still have an interest in the Mac world . 
- I installed & got REW running smoothly on a late 2010 Mac-Mini using an * AVID MBox Mini ( 3rd Generation ) * as the soundcard .
- The Mac Mini was running 10.6.4 .
- The * M-Audio Fast Track * line of products is largely just a less expensive version of the offerings from MBox .
- Up until ( your experience here ) I would have assumed your Fast Track would have been a "no brainer" to get working ( so much so, that I've considered buying it ) .

So much for assumptions !

















Perhaps JohnM has some ideas .


<> EarlK

*PS (edit )* : Okay, read  *this iMac success story . * 
- Half-way into the thread another poster ( mtbdudex ) mentions following a certain protocol that gets his 2007 iMac working properly with REW5 . 
- His setup is something that you have yet to try . So there is still hope !
- His 2-part solution involved installing M3D Mixer ( an output mixer that is a JAVA add-on from the following link ) & then within REWs preferences window ( for input device ), he chose "Built-in Input" .


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## JohnM (Apr 11, 2006)

That scope plot looks like an in-room measurement, pretty odd if you only have a loopback connected. Do you hear the sweep when you make the measurement? Wouldn't expect to if it is just looped back to the input.


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## Cizonor (May 15, 2011)

Okay, so I downloaded the M3D mixer, tried the whole two-part solution, and still no luck. I know the plot looks like an in-room measurement, but I can assure you that everything is properly set up for the test. I am not hearing anything, just watching the input LED light up as the test signal is run through it. I did the exact same set-up on a PC and it worked perfectly. I also tried running another measurement program, Fuzz Measure, to see if it came out with a different result on my soundcard, and I got the exact same measurement, which tells me that its not an issue with my soundcard, not an issue with REW, some type of issue with my computer, but for the life of me I just can't figure it out. The fact that my internal soundcard has the exact same measurement also suggests that there is something going on behind the scenes that I just need to locate. Ah, to be obsessed.


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## EarlK (Jan 1, 2010)

Hi Cizonor,

I agree with your assessment that the problem is not REW,( nor the Fast Track sound card, nor the iMacs internal sound card ) .


- Here are 4 different loop-backs that have been filtered through the RealTek Sound Manager ( which controls the internal sound card on my Dell notebook ) .

(i) Note how the graphic EQ effects the loopbacks linearity on the second pic .

(ii) Then note how the "environment settings" ( in the bottom 2 pics ) distort the loopbacks linearity ( even with the EQ still set to "flat" ) .

































- Perhaps if you're spending your time "gaming" with this computer you've engaged a similar environmental-acoustic setting ( somewhere within the iMacs audio settings ? ). That might effect the linearity of all your loopbacks ( though in the PC world, it would only effect the linearity of the soundcard the "environment" is meant to work with ) .

- Sorry to say, but at the end of the day , if this was my iMac ( & because this stuff is important to me ), I'd backup all my files and return the computer for a replacement ( assuming that I had first determined that I wasn't somehow the cause of the machines non-linear audio behaviour ) .

<> EarlK


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## Cizonor (May 15, 2011)

Earl,

That is very interesting. Although I don't do any gaming, I do a lot of audio stuff. I intend to wipe the hard drive and start from scratch. It will take some time to back everything up first, but I will report back with my results.

Thanks again for all your help.

Ciz


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## Cizonor (May 15, 2011)

I am pleased to report that after reformatting the hard drive the M-Audio Fast Track soundcard reads perfectly. Flat as a ruler. Couldn't have done it without your help Earl. Your last post alerted me to the fact that it was def software related issue. 

We're in business now!


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## EarlK (Jan 1, 2010)

Cizonor said:


> I am pleased to report that *after reformatting the hard drive *the M-Audio Fast Track soundcard reads perfectly. Flat as a ruler. Couldn't have done it without your help Earl. Your last post alerted me to the fact that *it was def software related issue*.
> 
> We're in business now!


That's really great news Ciz . I'm glad you got it going ( even if you had to resort to the "Nuclear Option" ) .

This was quite a unique problem / it would be nice to know what ( purged ? ) software was creating the problem . If it comes back, hopefully you can pinpoint the cause and let us know for future reference . 

Thank-you for adding to the knowledge base here at HTS ( your tenacity has really paid off ) . 

<> EarlK


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