TrueRTA Calibration Tutorial

[jets88]

]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

[radioflyer97]

I started usin TrueRTA when i got me PXA H701. This was the first tuning i did. Of course I've since tinkered with the SPX 17MB midbass settings so i'll have to re-tune from scratch later in the week.

[sonyslave]

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.

[avences]

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?

[goodstuff]

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

[captainobvious]

Originally Posted by goodstuff

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.
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

Ideas ?

[captainobvious]

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.

[stereo_luver]

If anybody is done with using this set-up let me know. I might want to give it a shot too.

[ratso1]

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.

[thazy2]

Hello gents.


Would a Youtube video of how to be out of the questions. I see it for everything els...


curious......

[goodstuff]

Originally Posted by captainobvious

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.

Missed this. What happened? I was going to suggest different cable or soundcard but I guess different computer works just as well.

[bikinpunk]

alright, I'll try to do a tutorial on using TrueRTA in the next few weeks.
Frankly, it's very easy to use as long as you have the appropriate gear (mic, good soundcard of some sort, and software).

So, what do you guys want to know? Try to be specific if you can. I'll do my best to write up a short tutorial soon.j


Actually, check out this thread:
Tuning your car using a pc based measurement setup

This has some good info on using the RTA. But, again, if fellas are having an issue with using the software itself, then I'll be glad to write short tutorial on getting started with TrueRTA sometime in the next week or two.

[ratso1]

Originally Posted by bikinpunk

On the audio setup (bottom right of the screen, right-click the speaker, then go to “adjust audio properties”, then click the ‘audio’ tab)…

Do you have the ‘sound playback’ set for the laptop’s sound card, and the ‘sound recording’ set for the microphone’?

your suggestion about re-doing the setup guide is a good one, i was really surprised by how bad the 'rta for dummies' thread is. no offense to the creator who put a lot of work into it. but rta themselves seems to be using it as their main manual and emailing them gave me no answers either. i think what is confusing to me is i don't get any of the above options when i right click my volume control. i take it it's different for vista 64? or is it just the built in soundcard for my dell? what i get is listed a couple of posts above and i'm still not sure how to set it?

[jbholsters]

Why would you need to use the pink noise generator in the software? That makes no sense at all. The software is just reading spl at frequencies. If the pink noise track on your CD was correctly made, it should work fine. Tell me why I am wrong.

[bikinpunk]

it's easier to generate and pause (stop) the pink noise from the laptop than it is to reach inside the car and pause it.

ie: convenience.

[jbholsters]

IC, I just run it until the battery goes dead. That stops is too.

[bikinpunk]

you need to get a bigger battery, mang!

[less]

Thanks for this info folks. I've had my collection of RTA goodies for a couple weeks now but am only now getting the chance to play with it some. I really wish I'd just dropped a few more buck and went for the Maudio usb instead of going with the mic mate - because most everyone here is using the M-audio or a similar device.

I've got a good selection of software in addition to TRUERTA - including synrta - winmls - ARTA and others, and I am interested in trying some of the things NPD did in his thread that is linked above - such as using impulse tests to time align perfectly... but for some reason I can't get winmls to give me a machine number so I can register for the trial period. Are there other software programs out there that allow for this type of testing? I've been using discs instead of the built in generator, but I wonder if using the generator, the timing could be synced and the timing could be checked using TRUE>

Also - I'd like to learn about gated testing and impulse testing. IF anyone runs into particularly informative posts (the For Dummies level is probably about right for me lol - but I'll brave higher order info too), please link'em up!

Thanks again. Erin, I appreciate your taking the time to share this stuff... I know its easier just to do it on your own and shut up!

Jim

[jets88]

Originally Posted by ratso1

your suggestion about re-doing the setup guide is a good one, i was really surprised by how bad the 'rta for dummies' thread is. no offense to the creator who put a lot of work into it. but rta themselves seems to be using it as their main manual and emailing them gave me no answers either. i think what is confusing to me is i don't get any of the above options when i right click my volume control. i take it it's different for vista 64? or is it just the built in soundcard for my dell? what i get is listed a couple of posts above and i'm still not sure how to set it?

i just setup truerta on my vista 64 bit computer yesterday. rightclicking the speaker icon will give you 4 options. All of them except open volume mixer will open the same box. i only played with it for about a half hour and this is what I did. I set the mobile pre as default in both the recording and playback boxes. I first looped chanell one to itself and turned the volume knob on the mobile pre up untill I got the clipping light on and then backed off untill it went off. It's funny I couldn't get a flat line that way on channel one.

I then tried channel 2 and looped the channels to themselves and set the volume untill right before it clipped and it worked. I got a flat line. I kept the settings in the volume controller the same, mobile pre default, I can't remember where I set the volume in the recording and playback windows now but I know I used either 1/2 or full volume. i'm not sure why channel 1 didn't work either. Just remember to switch the mike input if you switch channels on the mobile pre.i'm gonna play with it more on the weekend and see if I can get channel 1 working. Also remember to use the right channel on truerta if you use channel 2 on the mobile pre. Hopefully this helps.

[jbholsters]

OK, so I am trying to calibrate this thing. I have a moble pre. I hooked up a 1/4" jack from 2/R in the output section and ran it to ch2 inst/line on the input section.


Is this right so far?

In the original post is says:
"In playback side all sliders except wave/mp3 and master volume should be muted. If you can't see the line-in slider, enable it through options/properties and mute it. This is crucial if you don't want to have some nasty microphone feedback. In recording side select line-in, if you can mute the others, do it."

Slide all sliders where? To max volume?
If I check the mute box in Master (mine says speakers) it is a "mute all" button.

[leorbolato]

Great, thanks...

[Lars Ulriched]

I got Beringger mic to do this but dont have the usb sounds card and been looking for the M audio card but unable to find it here.....can anyone tell me if I can use this instead Sound Blaster X-Fi Surround 5.1?

[jets88]

Originally Posted by Lars Ulriched

I got Beringger mic to do this but dont have the usb sounds card and been looking for the M audio card but unable to find it here.....can anyone tell me if I can use this instead Sound Blaster X-Fi Surround 5.1?

It looks like it should work. It has 1/8 " jacks so make sure you have the right cables to calibrate. You'll aslo need a XLR to 1/8" converter for the mic. I've only used the mobile pre so I can't be positive it'll work but give it a try and let us know how it works out.

[thazy2]

Anyone of you Pro's or semi-Pro's care to make a YT video for us dummies? We just cant figure it out. If you need expense money, i can help.....


I think the video will help many Newbies...............................





thanks.

[OBXTINTWORX]

i am trying to use TrueRta as an SPL meter.
I have the DBX Rta Mic and a micmate.
i can't get any reading over 122db!
The three cars i tested all should hit louder than 122.
any input is appreciated.