Jig question

[guru_jeff]

Do I need a wallin jig or is there something else that is simple out there? I'm a little intimdated by the complex schematic

I've purchased a Behringer ECM 8000, Behringer xenyx 802, M audio transit sound card. I plan to use ARTA to measure FR and speaker parameters.

[claudio]

Hi Jeff,
for acoustic measurements you can use a simpler jig: check my home page, you will find all the infos. Be aware to use lot of care, not to burn your Transit.

[guru_jeff]

All I saw on your website is the wallin jig. I must be missing what you are refering to

[claudio]

For acoustic measurements: folder SW Acoustic. Meas. / Cables

For electric measurements: folder SW Setup / Cables

[guru_jeff]

what were you refering to when you said be careful not to burn my transit. Is there an order in which I should connect the wires or is it the line in must be set at a certain voltage level or something so I don't overload it.

[claudio]

You must take into consideration that usually the sound cards max input voltage is 2.5 V or less, therefore feeding your LINE IN with an higher voltage will cause damages to your card.

It's all written in my HP, please take some time to read it all.

[augerpro]

Couldn't he use a voltage divider similar to what is used for Soundeasy to protect his card?

[claudio]

Sure he can, I describe this option (voltage divider) as well, in my HP.

In acoustic measurement, using the jig I suggest, there is not the need of any voltage divider IF you pay attention to the mic-pre volume; when using the reference coming from the amplifier output, however, you need a voltage divider. I don't use, and therefore compensate, the amplifier output as reference, being its response flat in the audio spectrum.

[mightydub]

I built a jig that essentially the cables Claudio described, but in a box with a couple of switches to make it easy to go from calibration mode to measuring Z or frequency response. I found that my sound card has enough drive on the line out for doing impedance measurements.

Study Claudio's tutorial and start with a really basic jig - you can modify and add to it as you go.

Thanks Claudio for your tutorial - it really helped me get going with Speaker Workshop.

[claudio]

Originally posted by mightydub

Thanks Claudio for your tutorial - it really helped me get going with Speaker Workshop.

I'm glad it helped you out!
Many informations of my tutorial can be used for others measurement programs as well.