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Well,

I tried calibrating my notebook soundcard. Hopeless. Going to wait till the Mobile Pre comes in to do any more. Just running the O-scope with a sine wave output and moving the mouse causes RFI on the trace. Tried running the system cal several times, and quick sweep curve looks like playing a game of artillery on one of those old PET computers -far from flat.

TD
 

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Well,

I tried calibrating my notebook soundcard. Hopeless. Going to wait till the Mobile Pre comes in to do any more. Just running the O-scope with a sine wave output and moving the mouse causes RFI on the trace. Tried running the system cal several times, and quick sweep curve looks like playing a game of artillery on one of those old PET computers -far from flat.

TD
many of notebook soundcard is good, my internal soundcard is very flat. better not to calibrate your notebook soundcard.
first time use True Rta i use the callibrate one but the measurement is never been accurate, i use clio and lms to compare with the true and my notebook soundcard.
this it the picture of notebook, just use loop without any calibrate

my notebook audio in/out


looping mic and headphone out


loop aux and headphone out


i use averege 10, speed trade fast, all calibration off.

but you better use external devices cause more accurates and more reliable than internal one.
i use BB-measurement for mic and the soundcard.
http://bb-measurement.tripod.com/
 

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I hate bringing things back from the dead but wasn't sure that this deserved its own thread. Did anyone ever figure out how to get TrueRTA to show A-weighted curves? Looks like out of the box readings are linear not C-weighted. It's not complicated to apply the corrections just tedious.
 

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You have to use the program's generator and send the signal through your h/u and out through your system via the aux input on the h/u. you have to have a feedback setup, too. otherwise, there's nothing to reference itself to. Basically, loop your input/output. Instructions are on the first page of this thread, I'm pretty sure.
ahh this is the part I overlooked. So if you dont have an AUX port on your deck you are SOL?
 

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Found this on the TrueRTA FAQ:

"Do I need to calibrate TrueRTA with the voltmeter if all I am using it for is the audio analyzer?
No. You only need to calibrate it if you are going to make voltage measurements where the absolute voltage or dBu level must be known. If you are only interested in relative measurements like "there is a peak of +6.25 dB at 500 Hz compared to the rest of the response" then voltage calibration is irrelevant.
If you do not calibrate TrueRTA then the actual Line-In and Line-Out levels will be unknown. When you set the generator output level to -10 dBu the actual output level may be considerably higher or lower. Similarly, an input signal that reads -10 dBu may actually be higher or lower in level."

 

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]Hi I just bought an m-audio mobile pre and I'm unsure about how to calibrate the thing to work with the trurta software. I'll be using the behringer mike connected to one of the xlr inputs. It's hooked up to an acer aspire one via a usb cable. I searched but couldn't find an answer. I haven't tried to hook it up yet because I haven't bought any cables yet and I'd rather not spend the money on any cables I don't need. Any help would be appreciated. Thanks





 

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I stumbled onto DIYMA last night. And this thread is pretty cool! Nice to read so many intelligent posts in a single thread.

I realzie that rta is probably being used to measure setup for competition, just wanted to throw in my .02. Ears are pretty subjective things, different people hear the same sounds a little differently (just as color perception to the eye is very subjective and some people see color (or not) differently than others. Factor in hearing loss due to high spl exposure and that further complicates things.

Using measurement tools to get flat response is great, but don't forget to tune for your own listening tools, your ears! A audibly pleasing setup is not always a sonically accurate one.

A tip: I would recommend monitoring your mic while doing measurements. Use a quality set of headphones to make sure the mic is "hearing" things accurately. The typical gear is not immune from extraneous RF noise (like cellphone emmissions, radio towers etc). If that stuff creeps into the signal while doing a measurement it could throw off your graph.
 

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something weird happened to me last night that i was doing test, I have the behringer Mic (the one that recomend) and a mic mate.

I run the program and the room where i was staying it was in silence, but the rta read some noise, for the level of the noise measured i thought it was like a bad ground in one cable so i started to unplugged everything one piece at time.

I took out the mic.....and the graphic didnt went to 0 it kept almost the same with no mic!!! so i was like...what the heck? then i unplugged the micmate, the graphic showed and dissapeared...then showed again but with a minimal amount then dissapear...i though well....it is done....i was looking at the screen and suddenly the sound appeared in the graphic again....something is buzzing i guessed.

Then i realised that the internal fan of the laptop was working.......there was no mic attached....can it interfiere with the measures?
 

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Bringing this one back from the dead. Finally got going on this. Got the software working. Calibrated the sound card. Loaded the better beringer mic correction file. Using uncorrelated pink noise test disc I attempted to take measurements with all speakers playing at once. I guess I should I be playing them one at a time? Now from rereading I guess I need to run the signal (pink noise) from true rta into the aux input of the deck and then measure with the mic. Also the loop back needs to be connected at the same time? Also noticing the shortcomings of the drz eq, mainly no independent eq for hi /mid /low. On a side note the cpu I was using started repeatedly crashing after I took some measurements. I tried swaping a bunch of hardware around, thought it was memory, os virus, harddrive, videocard. Turned out to be the resolution was too high, even though it ran fine and looked fine for a while. Had me stumped. Discuss
 

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Bringing this one back from the dead. Finally got going on this. Got the software working. Calibrated the sound card. Loaded the better beringer mic correction file. Using uncorrelated pink noise test disc I attempted to take measurements with all speakers playing at once. I guess I should I be playing them one at a time? Now from rereading I guess I need to run the signal (pink noise) from true rta into the aux input of the deck and then measure with the mic. Also the loop back needs to be connected at the same time? Also noticing the shortcomings of the drz eq, mainly no independent eq for hi /mid /low. On a side note the cpu I was using started repeatedly crashing after I took some measurements. I tried swaping a bunch of hardware around, thought it was memory, os virus, harddrive, videocard. Turned out to be the resolution was too high, even though it ran fine and looked fine for a while. Had me stumped. Discuss

When i hear about this "loop back" it doesnt make sense to connect the laptop input to its output with a cable IF you are using a micmate. Think about this...you will never USE the mic/aux input on the laptop as your input is coming directly from the usb/micmate. So I think you are correct. Sounds like we (I say we because I just picked up the same setup) need to:
1. Connect the micmate to the usb port.
2. Connect the laptop headphone output to the rca/aux input on the Head Unit.

Now the True RTA program should be able to send its signal through your head unit and be able to record it with the mic/micmate.

My problem is that Im seeing a 40db peak fom 5K on up when just trying the pink noise out of the laptop speakers and recorded through the micmate. Its pretty flat from 20hz on up to 5K but then its a massive hump from 5K-20K. I unplugged my mic from the micmate. All output drops across the board, but theres still a big hump shown from 5K-20K. :confused:
I figured it might be room noise, but doesnt make sense for it to be that loud and it really doesnt make sense to see it when the mic is disconnected :eek:

Ideas ?
 

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Hmm...odd. Must be something with my laptop. Tried it on my other laptop and it is nice and flat. Time to take some in car measurments and see what happens. :)
 

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way back on page one, braves6117 asked a question that was never answered. i have the same question - can anyone help me? i also emailed this to trueRTA but never received a response. i think it has to do with the fact that right clicking on the volume control gives a different response with vista than older systems (or maybe it's just with dell laptops)? anyways to quote what i sent to trueRTA:

when i right click on the sound icon in vista, i get 4 choices: either to choose the mixer, playback, recording devices or sound. sound is obviously not right and neither (i think) is the mixer. if i choose either playback or recording it opens a three tab window. under playback i get speakers/headphone, independent headphones and line 1//2 mobilepre. i can enable and disable these but no "mute". i have all "enabled" and the preusb has a green check next to it. is this correct? under recording i have internal mic (disabled), microphone line/in (currently unavailable), rec playback (working) and the preusb (working, green checkmark). again is all this correct? sorry to be so specific, just wanted to make sure i'm telling you everything.
 
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