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Looking for some opinions on which setup is best for someone interested in using a laptop for Real Time Analysis of a car audio system?
Software? (Free vs paid) and what Mic setup is good, better, best?
 

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TrueRTA, ARTA, and SMAART with a calibrated microphone and something like the USB MobilePre for your preamp are the way to go. Just a warning, if you go with the USB MobilePre, you will have to make your own cables.
 

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Funny. After purchasing TrueRTA, I finally messed around with REW's RTA and it looks more than capable to me...

Unless I'm missing something I think REW is just fine vs. TrueRTA. And its free.
 

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this is my RTA
run it off my ASUS tablet, and a usb converter, and a dennon ribbon mic. no stand. i havnt used it yet my self yet, still learning how to tune. i havnt gotten my setup set up 100% yet :\
 

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Discussion Starter #6
this is my RTA
run it off my ASUS tablet, and a usb converter, and a dennon ribbon mic. no stand. i havnt used it yet my self yet, still learning how to tune. i havnt gotten my setup set up 100% yet :\
Eviling, what program are you using?
 

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Trurta
 

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I like this
 

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TrueRTA is the easiest software to use.
ARTA, HolmImpulse, and REW are all good free programs to use but ate a bit more complex...though, they give you much more information than truerta. The level you need is dependent in what you want to do.

In short: pure RTA program goes to true. Otherwise, the free ones have more power and are free, albeit more complex.
 

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TrueRTA is the easiest software to use.
ARTA, HolmImpulse, and REW are all good free programs to use but ate a bit more complex...though, they give you much more information than truerta. The level you need is dependent in what you want to do.

In short: pure RTA program goes to true. Otherwise, the free ones have more power and are free, albeit more complex.
but in what way is it easier to use? i havent used true RTA, but ive used REW, and for frequency sweeps REW is really easy to use, so for that purpose i think it makes zero sense to spend $40.
 

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you hit "go" and you're recording. that simple.
You can use your own cd as well, so there's no need to have cables running from the laptop to the headunit/dsp/whatever source you want to use to playback the stimulus. The benefit not only lies with using pink noise cds of your own and saving cabling... the real benefit IMO is being able to watch music as you listen. For example, if you hear a note in a song that doesn't sound right, you can use TrueRTA to figure out where that peak may be. It's not easy, but it's doable. You can't do this with an FFT based program.
Of course, you have the option to use true to generate the stimulus but it's not a must.

aRTA and Holm both use FFT based measurements. Does REW do FFT only or does it also record live (RTA)? If it's only FFT (gated impulse) then trueRTA wins out for the car audio crowd.
While I'm not saying this is bad, it is a bit more confusing to the newcomer. Especially when they're trying to determine what the window size should be and adding to the fact they have to use cables to generate the tones/sweeps/noise. With True you can pop a cd in and record live. Just 'simpler' overall. In car audio, the use of True makes more sense; there's no point in windowing the impulse given the amount of reflections.
 

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you hit "go" and you're recording. that simple.
You can use your own cd as well, so there's no need to have cables running from the laptop to the headunit/dsp/whatever source you want to use to playback the stimulus. The benefit not only lies with using pink noise cds of your own and saving cabling... the real benefit IMO is being able to watch music as you listen. For example, if you hear a note in a song that doesn't sound right, you can use TrueRTA to figure out where that peak may be. It's not easy, but it's doable. You can't do this with an FFT based program.
Of course, you have the option to use true to generate the stimulus but it's not a must.

aRTA and Holm both use FFT based measurements. Does REW do FFT only or does it also record live (RTA)? If it's only FFT (gated impulse) then trueRTA wins out for the car audio crowd.
While I'm not saying this is bad, it is a bit more confusing to the newcomer. Especially when they're trying to determine what the window size should be and adding to the fact they have to use cables to generate the tones/sweeps/noise. With True you can pop a cd in and record live. Just 'simpler' overall. In car audio, the use of True makes more sense; there's no point in windowing the impulse given the amount of reflections.
I use the RTA on REW

RTA Window

not sure about the FFT stuff.. and if anyone else looking to spend $40 is not sure either then its likely they dont need to spend $40..? I would recommend people who have an EQ setup try to use REW first and then if they feel it lacking go to true RTA.

dont see why you cant use a cd with rew either (although i dont see why anyone would want to do that... ive never viewed it as a "benefit")
 

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I use the RTA on REW

RTA Window[/url


Looks like you're good to go, then. Live RTA is something most response measurement software doesn't have. In fact, if it doesn't have live measuring, then it's not RTA by definition. But, it looks like REW does have it, and the options look good as well (similar to True). Having not used this feature (that I recall), I'll just say by spec that it looks to be an easy rival to True.

not sure about the FFT stuff.. and if anyone else looking to spend $40 is not sure either then its likely they dont need to spend $40..? I would recommend people who have an EQ setup try to use REW first and then if they feel it lacking go to true RTA.

dont see why you cant use a cd with rew either (although i dont see why anyone would want to do that... ive never viewed it as a "benefit")
FFT/Impulse/Windowing has it's place and can be a great tool when used wisely. If you don't know what it means you should read up. TrueRTA doesn't have this feature.

dont see why you cant use a cd with rew either (although i dont see why anyone would want to do that... ive never viewed it as a "benefit")
I don't see anything that says you can't use a CD with REW. My point was that with programs that do impulse measurements, it's almost always required you use some sort of loopback system so the program knows when the signal was sent and it can do it's own delay to get the appropriate received time of response. From there you can do your own window to filter out environment-based response additives. This requires cabling. Sometimes that cabling can be a bit of a PITA (ie: if you use a mobile pre and you have to make your own cables for the loopback portion as mentioned by ChrisB, above).

I certainly view the ability to not have to use a loopback system as a benefit for one reason: less cabling.
Now, I often still use the software's generator simply because I can pause the noise directly from the program. BUT, I carry the laptop measurement rig around to a lot of car audio shows/meets and others' homes to do measurements. In some of these cases an AUX may not be as accessible as the CD player itself. In some cases, such as with Pioneer headunits, the aux input is not standard. These reasons are why I find the ability to use a CD source as the stimulus more accommodating. In other cases when an AUX is accessible (and I happen to have the appropriate aux connector available whether it be 3.5mm or L/R RCA), I'll use that along with the software to generate the stimulus.

Furthermore, as I mentioned above, the ability to use real music is HUGE. You can pick out key hotspots you may not otherwise catch via pink noise, which has been shown by Toole to not be as reliable for noting resonances. Music is the only source that can highlight certain issues such as resonance and for those less trained in the art of golden-earings (hey, funny joke!), having an RTA to key in on certain trouble frequencies is invaluable. I've done this many times myself.



All that said, REW certainly looks like a good alternative to True. I'll have to give that a go again.

FWIW, I'm now using Datyon's OmniMic system for my measurements.

- Erin
 

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Would a microphone that came with something like the Denon AVR-3808 or the Pioneer DEH-80prs be sufficient to use as a calibrated microphone with one of these programs?
 

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Looks like you're good to go, then. Live RTA is something most response measurement software doesn't have. In fact, if it doesn't have live measuring, then it's not RTA by definition. But, it looks like REW does have it, and the options look good as well (similar to True). Having not used this feature (that I recall), I'll just say by spec that it looks to be an easy rival to True.



FFT/Impulse/Windowing has it's place and can be a great tool when used wisely. If you don't know what it means you should read up. TrueRTA doesn't have this feature.



I don't see anything that says you can't use a CD with REW. My point was that with programs that do impulse measurements, it's almost always required you use some sort of loopback system so the program knows when the signal was sent and it can do it's own delay to get the appropriate received time of response. From there you can do your own window to filter out environment-based response additives. This requires cabling. Sometimes that cabling can be a bit of a PITA (ie: if you use a mobile pre and you have to make your own cables for the loopback portion as mentioned by ChrisB, above).

I certainly view the ability to not have to use a loopback system as a benefit for one reason: less cabling.
Now, I often still use the software's generator simply because I can pause the noise directly from the program. BUT, I carry the laptop measurement rig around to a lot of car audio shows/meets and others' homes to do measurements. In some of these cases an AUX may not be as accessible as the CD player itself. In some cases, such as with Pioneer headunits, the aux input is not standard. These reasons are why I find the ability to use a CD source as the stimulus more accommodating. In other cases when an AUX is accessible (and I happen to have the appropriate aux connector available whether it be 3.5mm or L/R RCA), I'll use that along with the software to generate the stimulus.

Furthermore, as I mentioned above, the ability to use real music is HUGE. You can pick out key hotspots you may not otherwise catch via pink noise, which has been shown by Toole to not be as reliable for noting resonances. Music is the only source that can highlight certain issues such as resonance and for those less trained in the art of golden-earings (hey, funny joke!), having an RTA to key in on certain trouble frequencies is invaluable. I've done this many times myself.



All that said, REW certainly looks like a good alternative to True. I'll have to give that a go again.

FWIW, I'm now using Datyon's OmniMic system for my measurements.

- Erin
@bikinpunk , you seem to be very knowledgeable in this subject, i just pmed you a question, if you could get back to me id appreciate it! thank you
 
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