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CauYem
08-31-2008, 01:12 AM
I need help from the expert to make a set up to measure audio response. Please advise on which RTA program to use & equipments needed. I don't want to spend a lot of money & end up with a whole bunch of useless stuffs as I did with other hobbies.

Thanks.
Cau Yem

richluvsound
08-31-2008, 01:51 AM
Google "SMAART"

Robh3606
08-31-2008, 07:09 AM
Try the free version of True RTA. If it works well in your computer you can purchase an upgrade for reasonable money. Make sure you check it out before you order an upgrade. I have had issues with it in 2 different computers and sound cards so make sure it's working well first. You are going to need a measurement microphone and a phantom power source. The Behringer ECM 8000 is good for the money and you can get a battery powered Crown PH-1A phantom power source off E-Bay or find another alternative like an inexpensive mixing console.

That's probably the cheapest way to get an RTA set-up unless you go hardware and purchase one of the inexpensive Behringer set-ups like the 8024 that have the RTA built in. In that case you won't need the software or the phantom power source. If you go the hardware route you can sell it once you are done with it. Any of the free or inexpensive software you will not be able to that.

Price it out.

Rob:)

http://www.trueaudio.com/rta_down.htm

CauYem
08-31-2008, 10:42 AM
Thanks for the quick response!
I spent many hours last night (stayed up until 3:30 am) to search on the net, and came across many RTA (including SMAART) with different prices with different recommended equipments. Most RTA programs work (recommend) with certain sound card, microphone & calibrator.

I need help from the from the experts, who already have a working set up so I can get it running the first time. My intention is to get a medium level set up for long term use. I can spend some money for the set up, but not the exuberance price for some of the RTA/equipments I found on the net.

Robh3630,
Thank you for suggesting True RTA along with the Behringer ECM 800 & Crown PH-1A. What are using for your measurements? Would please advise me on the complete list of equipment needed?

If you have pictures of your working set up, would you please send or post them up so?

Thanks,
Cau Yem

boputnam
08-31-2008, 11:41 AM
If it were me being you, I'd think about starting with the Gold Line 30M8 RTA (http://cgi.ebay.com/Gold-Line-30-M8-audio-RTA_W0QQitemZ200250598091QQihZ010QQcategoryZ113484 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem).

This example will surely sell inexpensively, and has some good functionality. A great starter unit.

The description sounds identical to the way mine works - I'll bet there is nothing wrong with this unit.

Robh3606
08-31-2008, 01:07 PM
I use a Behringer 8024 as my RTA. It's a stand alone unit. Here's another free software package you would need a Microphone and Phantom power source for.

http://www.libinst.com/SynRTA.htm

http://www.cheapbandgear.com/MICROPOWER_PS400_p/ps400.htm

Rob:)

Mr. Widget
08-31-2008, 01:11 PM
For ease of use I'd suggest a stand alone unit like one from Rane, Behringer, or one of the many others.


Widget

Zilch
08-31-2008, 01:34 PM
http://audioheritage.org/vbulletin/showthread.php?t=19843

grumpy
09-01-2008, 03:13 PM
A laptop, cheap measurement omni, TrueRTA, (as have all been mentioned)
and toss in one of these:

http://www.fullcompass.com/product/344718.html

(Mic preamp with phantom power and USB output)

make for a portable system as well, and inexpensive if you already have
some of the components.

I don't -strongly- recommend this particular unit, but it is inexpensive
and will work with normal listening levels. Note that at higher SPLs, even
at the lower gain setting, you can unintentionally run it into clipping
(which you can monitor with the oscilloscope function of TrueRTA).
If you don't pay attention to this, your results may be somewhat ...
confusing until you realize what's going on.

Regardless, get a stand for the instrument or mic. Helps with placement
repeatability... and your body -will- affect the measurement.

CauYem
09-01-2008, 04:57 PM
Thank you all for your help!

I can afford a mid to hi-end set up for more accurate measurements. I don't want to buy more stuff than I need. This is for a long term project. I'm thinking of either the "Clio" or "Spectraplus" (www.spectraplus.com (http://www.spectraplus.com)) set up. I need help to avoid any rookie mistakes. All of your advises are much appreciated!

Right now, I need is SPL, Phase & Impedance measurements for my presentations at first, but any "value added" graphs will help. I'm working on some custom crossover designs.

Thank you all for your help & advices.

Zilch
09-01-2008, 05:02 PM
CLIO Lite.

Upgrade later.

CauYem
09-01-2008, 05:16 PM
CLIO Lite.

Upgrade later.

Thanks Zilch

What do I need for the set up?

Mr. Widget
09-01-2008, 06:16 PM
What do I need for the set up?You need a PC or Laptop that has XP on it and $1200 for CLIO Lite and the mic.

http://estore.websitepros.com/1736754/Detail.bok?no=129

http://estore.websitepros.com/1736754/Detail.bok?no=272

It is very easy to learn and if you buy this book and read it, you will be able to make meaningful measurements.

http://www.madisound.com/catalog/product_info.php?products_id=143


Widget

Robh3606
09-01-2008, 09:27 PM
I don't want to spend a lot of money

Your looking at CLIO?? So what's your real budget in dollars??

Rob:blink:

CauYem
09-01-2008, 09:41 PM
Your looking at CLIO?? So what's your real budget in dollars??

Rob:blink:

Willing to pay around $1,500.00 or more for an accurate set up. I've been searching around the net & found there are many more RTA set ups than I thought.

I'm interested in both Clio & SpectraPlus systems. Need more advise on microphone & misc stuffs.

1audiohack
09-04-2008, 08:29 AM
Have you looked at the LinearX pcRTA?

I have the Goldline two channel RTA that works with TEF, when using it for sound system set up in conjunction with TDS measurement, that gets it done with one box and a laptop.

If I were using RTA (I wouldn't) for speaker and crossover development without the need for TDS, I would seriously consider the LinearX. You are then in the best of company should you want to purchase driver measurement (LMS) equipment and modeling software like EnclosureShop and or CrossoverShop. I have all of that and will recomend it to anyone.

The manuals, documentation and support you get from them is the best I have ever seen, although I havent seen it all!

Have fun, its a great journey.

Robh3606
09-04-2008, 09:30 AM
You are then in the best of company should you want to purchase driver measurement (LMS) equipment and modeling software like EnclosureShop and or CrossoverShop. I have all of that and will recomend it to anyone.


Yes I would have to second that. Their software is simply awesome. I use CLIO for my measurements and I am happy with that as well.

Rob:)

CauYem
09-09-2008, 06:02 PM
I've received all the parts for the RTA set up: a Beringer ECM8000 microphone, a USB M-Audio MobilePre (w/ phantom power), microphone stand, microphone cables, interconnects, a XP laptop and various RTA software.

The set up was connected to an McIntosh MC275 amp & a pair of Klipschorns in my living room. I was so surprised (and amazed) on my first run, the system was very sensitive. It picked up the noise from the air conditioner vent, and also from my laptop fan (very quiet). My body movements were also recorded on the graph. My laptop & I was about 13'-15' from the microphone, which stood in front (about 3') away of the Khorn. Graphs of Ampl vs. Feq, Phase vs. Freq... were display nicely.

I didn't save the file since the system wasn't calibrated yet. I played a little bit it by adjusting the level on the pre amp to see the response moved up & down. I just want to verify that the system functions the way it should. I'm happy with what I get for my work. I need to prepare for a more appropriate room for the test; my living room isn't the place. I need time to learn do the measurement correctly. I'll buy different microphone to test & compare to the ECM8000.

Thank you all for your help!