Arta?

[donradick]

Looking for a good basic package to do some measurements. I've played a bit with the free version, and it looks like the registered version will also give me impedance measurments. I've got a recent HP laptop with Windows 7, so the full-duplex sound card should be ok.

So, should I go for it, or should I knuckle down and try to learn SoundEasy?

don

[billfitzmaurice]

Re: Arta?

I prefer HolmImpulse. You will have to find instructions how to use it (there are a few on various forums) as it doesn't come with them.

[Froste]

Re: Arta?

I may be wrong, but I think the Free version of ARTA will allow you to make ZMA files. (will need to build a Jig(test box)).

[Face]

Re: Arta?

I may be wrong, but I think the Free version of ARTA will allow you to make ZMA files. (will need to build a Jig(test box)).

No, you need a registered version. A jig isn't required though, but it would be preferred.

[diy speaker guy]

Re: Arta?

No, you need a registered version. A jig isn't required though, but it would be preferred.

I've been using LIMP (the part of ARTA used for measuring t/s parameters) unregistered for at least the last 2 years. I can't remember if it will let you save the file as a zma directly but that isn't necessary since you can just trace the impedance sweep. A jig is absolutely required, it connects the device under test to the computer. It's only 1 resistor and a couple of 3.5 mil jacks, very easy to make. It doesn't even matter what value the resistor is, as long as you know what it is.

A single sweep can take up to 3 minutes or so, if you can't live with that you might be happier with a woofer tester. Otherwise, I recommend LIMP very strongly. If LIMP had not worked for me I would have tried Speaker Workshop next but that program requires a slightly more complicated jig.

I do not like the other 2 parts of ARTA for frequency response measurements, I only use LIMP for impedance. I prefer Room Eq Wizard and HolmImpulse for my frequency response measurement needs.

[critofur]

Re: Arta?

I've used it to measure impedance (it's a another program in the ARTA folder, called LIMP? I think>) - I also think I was able to use it with free version. I simply hooked up the resistor + aligator clips version of the "jig".

I got tired of getting confused with my jig and problems with my soundcard etc, so I got WT3 and find it much more convenient. Anytime I want to measure a driver (not FR) it's quick and easy...

[charlielaub]

Re: Arta?

I can highly recommend ARTA for frequency respones measurements. I use this all the time. It has a good manual, and once you get the hang of how to do it, it works great. For best results you need a calibrated mic. Although the PE version of the ECM8000 is good, for better accuracy and a wider range of calibrated frequencies, you can get a calibrated ECM8000 from Cross Spectrum Labs in Springfield, MA. This is a sample calibration report. Don't forget that this mic needs a phantom power supply or a mic preamp with phantom power!

The procedure with ARTA for measuring FR is:
1. Impulse measurement
2. Set Gate times on measured impulse
3. Perform a gated frequency response measurement
This will get you FR without phase. You can also perform a more complicated version that requires two input channels but will also give you phase.

One other tip that you may not know about is that, for the best results with this kind of measurement, the speaker should be moved away from boundaries such as walls, the ceiling and the floor. PE sells an inexpensive Pro Monitor tripod stand that is great for this purpose. You need to bolt a small piece of wood on to the part of it that is designed to be screwed in to the monitor, and then put your speaker on that, about half way between floor and ceiling, and at least that far out from the walls.

I haven't used LIMP, since I have a woofer tester. The WT is super convenient and doesn't require a jig. It's worth it if you will measure drivers on and off, since it's more or less plug and play. This also gives me the piece of mind that I will not connect my jig wrong, and send voltage in to my sound card that will fry my computer!

-Charlie

[markk]

Re: Arta?

PE sells an inexpensive Pro Monitor tripod stand that is great for this purpose. You need to bolt a small piece of wood on to the part of it that is designed to be screwed in to the monitor, and then put your speaker on that, about half way between floor and ceiling, and at least that far out from the walls.

-Charlie

Hey, I use that. It works really well and it's on sale...

[donradick]

Re: Arta?

Thanks guys!

I do have an ECM8000 (uncalibrated) and a Rolls preamp that I got a few years ago on the 'bay.

I've got several boxes of buyout drivers I've accumulated over a few years, and I dont build that much, so the plan is to use the free LIMP for ZMA plots, and HolmImpulse and free ARTA for FRD plots.

Good tip on the PE pro monitor stand. Been meaning to get one of those, along with a mike boom.

don