PDA

View Full Version : Need Recommendation for Analyzer (FFT, TDS, etc.)



David Dryden
01-24-2005, 06:19 AM
Hi guys. I need a recommendation for some analyzer software. I've been out of the loop for a number of years, so I'm not familiar with what's the latest and greatest. In addition to designing sound systems for schools and small venues, I also will go out and tweek them after our installers get everything in place. Up to this point, I have been relying upon my ears and a small spectrum analyzer. This has worked fine for the most part, but I am working on a system right now that has a specification that requires documented proof of performance when completed. The spec suggests FFT (SMAART, Terrasonde, B&K) or TDS (TEF, MLSSA, WinMLS).

I had looked into SMAART at one time, and think it may do what I need, but I am not sure what the differences/advantages are between the FFT vs. TDS. Can someone help me decide what's best? :blink:

Mr. Widget
01-24-2005, 10:14 AM
I recently purchased the Clio system. It will do FFT measurements (similar to SMAART), as well as Sinusoidal (similar to LMS/Leap), and MLS (similar to MLSSA). I have been very happy with it.

You can get their Lite version with calibrated mic for $700. If you need more functionality it is a software upgrade. The manual is pretty good. You will also need to buy Testing Loudspeakers by Joe D'Appolito (http://www.amazon.com/exec/obidos/search-handle-url/index=books&field-author=Joe%20D%27Appolito/104-3953399-5975910)

In the States you can buy the lite version here. They also have a review of the older DOS version... most of the good is still there and much of the bad has been fixed. http://www.audioxpress.com/bksprods/kits/kc-cliom.htm

Widget

lfh
01-24-2005, 11:13 AM
In addition to designing sound systems for schools and small venues, I also will go out and tweek them after our installers get everything in place. Up to this point, I have been relying upon my ears and a small spectrum analyzer. This has worked fine for the most part, but I am working on a system right now that has a specification that requires documented proof of performance when completed.

To me it sounds that you need to be able to measure STI or RASTI. I suggest you look at the current TOTL (and $$$) for reference, e.g. EASE/EARS (http://www.renkus-heinz.com/ease/ease_intro/intro_about_aura.html) for simulations and MLSSA (http://www.mlssa.com/) for measurements. (At least this is what I think is TOTL - I've been "out of the loop" for a while myself...) At the MLSSA site, the full manual is available, as well as an overview paper that explains the capabilities of the system and the advantages of the MLS-approach in general. Most likely there are SW/HW packages that offer more "bang for the bucks", but the mentioned systems should offer some inspiration and insight into what's available.

Oldmics
01-24-2005, 05:22 PM
What are the proof of preformance requirements for the job you are now involved in?

You may need more than one tool to do your required test confirmations

All of the formats so far mentioned are excellent in there own rite.It is all about your specific application.

In my "live" application world,I prefer the FFT measurement system.

I personally use Praxis for componet evaluation and Smaart Live for complete system applications.Each program does something different and more precise for my particular applications.I also use Audio Control devices for other measurements (mostly STI) due to there ability to get the results faster.I have not yet had a call to preform a RASTI test.

Quote from Mr Widget

"You will also need to buy Testing Loudspeakers by Joe D'Appolito (http://www.amazon.com/exec/obidos/search-handle-url/index=books&field-author=Joe%20D%27Appolito/104-3953399-5975910) "


Just buy that book anyway!!!!! It should be on a must have list for anybody in audio.Great book.

Oldmics-Who has more acoustical questions than answers???????

David Dryden
01-25-2005, 05:35 AM
Thanks for all the responses. What the spec says is that they want left and right speaker system frequency response, center array frequency response, speaker system phasing, and SPL uniformity. We're using EAW LA-325's for left and right mains, an EAW DSA-250 for the center, QSC power amps and Rane DSP.

I know the specs aren't asking for anything real complicated, but they ask for written proof of performance. Besides, this is an opportunity to requisition the software and hardware from management to do this sort of thing, both for this and future jobs :D.

Will SMAART Live work for me in this type of application? Of course, I may *ahem*, borrow the system to check some things at home occasionally ;).

Oldmics
01-25-2005, 08:26 AM
For the specs that you need to fullfill,Smaart Live will do all those chores and allows for many more.

As with any new program acquired there is a learning curve to consider.

Hardware is also necessary to interface into your laptop computer(eg,analyzer mic and usb interface)This acquistion also needs to be calculated into your budget.

My other concern is that if more demanding acoustical measurement criteria is in your future,additional programs or stand alone hardware may become necessary for you to purchase.Other posts have referred to STI measurements. I believe the STI measurement is an up and coming demand for acoustical consultants.

Now even though Smaart Live will not do the STI measurements ,its sister program Acoustic Tools will allow for that chore.

The Acoustic Tools program is of coarse an additional purchase.

SIA (the vender of Smaart) will allow a discount when initially purchasing both programs.

And don"t forget "Testing Loudspeakers" by Joe D'Appolito (http://www.amazon.com/exec/obidos/search-handle-url/index=books&field-author=Joe%20D%27Appolito/104-3953399-5975910) " I highly recommend it.

Oldmics

David Dryden
01-25-2005, 09:07 AM
Glad you brought up STI. The company I work for does alot of commercial fire alarm business. It's not here quite yet, but I can see STI certification requirements looming on the horizon for voice fire alarms systems. Maybe we could get Acoustic Tools when the time comes.

With regards to hardware, I know SIA recommends and sells Earthworks lab mics, etc. They also mention the use of an outboard mixer and USB preamp. I have a Symetrix 2 channel mic pre. Connected to the laptop's stereo line in, would this suffice? Just trying to figure out how much smelling salts to have on hand when I go to the boss with my request! :crying:

P.S. Thanks for the book recommendation. I'll get it!

Oldmics
01-25-2005, 09:33 AM
In reality-any test quality mic that is reasonably flat will work as long as you have the calibrated files from the test microphones manufactor to enter into the Smaart system.Once the files are entered then the program smooths out any dips or peaks in the mic thru software correction.


The EarthWorks are great mics,just pricy.I am a dealer and can sell you those. If you want me to offer you pricing just send me a P.M.

Interface thru the laptops stereo line in can be done.You have to be able to control the right and left input signals independently.This means controlling the volume on and off independent of each side along with independent input level control for each side.If your laptop will not do this (and many will not)get a USB interface that will allow you this control.

I think that the Symetrix will probably work for you.

Oldmics