Speaker Testing Rig - your thoughts?

[AllisterMcRae]

I know it's not perfect and that the environment is a bit confined. But in 3 hours I was able to get full polars on horizontal and vertical for 2 drivers every 10 degrees.

I set listening height between the mid and tweeter. It's a bit physically high from the ground. But that can be changed in v2.

I did a bit of simple code to setup to give the vertical angle offsets. Horizontal on a notched turntable at 10 degrees per.

Eyes are a bit crossed from effort. But tempted to see the numbers on version with 1/2 roxul-filled cavities... Though these are full sized volumes designed around the drivers.

...excited for when the new tweeters arrive so I can get on the crossovers for this project .

What would you recommend as things that I should be doing here to improve the acoustic performance and/or efficient use of this rig?

[chrisn]

Maybe some pillows/blankets/insulation on the floor and above on the door. How did the measurements turn out?

[rpb]

I would simply check for issues off axis, out to 45 or 60 degrees, then design a x-over based on the on axis measurements. I only know of one member here that will argue this point. I imagine that he will chime in to say I'm wrong. I would estimate that 95% of the accomplished builders here do things the way I'm suggesting, and get the same end results. I'll not argue the point further.

[AllisterMcRae]

I would simply check for issues off axis, out to 45 or 60 degrees, then design a x-over based on the on axis measurements. I only know of one member here that will argue this point. I imagine that he will chime in to say I'm wrong. I would estimate that 95% of the accomplished builders here do things the way I'm suggesting, and get the same end results. I'll not argue the point further.

I need every word from those more experienced (and everyone, really), in simplifying how I'm going about all this. (God knows my attempt at "perfection" is killing my timelines). Thank you!

[AllisterMcRae]

Maybe some pillows/blankets/insulation on the floor and above on the door. How did the measurements turn out?

The little things. ...I wonder how heavy the door would get if I lined it with roxul (too heavy).

The measurements came out alright. Though I left it on automatic gating - I'm going to go in there and see if I can adjust some of the IR settings to get a better output.

As of right now:

[DeZZar]

Nice. I like the microphone mount.

This is what I came up with for the same problem a little while ago - has been working pretty well.
https://techtalk.parts-express.com/f...surement-stand

[AllisterMcRae]

Solid build. I love how simple and strong it is.

[billfitzmaurice]

I always measure outdoors in two steps. I first do a ground plane measurement, which gives the half space result below to baffle step. Then I face the cab up with the mic suspended above it, which gives the half space result above the baffle step. The two are spliced to give the final result. If I want polars I do that with the cab facing up by rotating the cab on either axis.

[AllisterMcRae]

I always measure outdoors in two steps. I first do a ground plane measurement, which gives the half space result below to baffle step. Then I face the cab up with the mic suspended above it, which gives the half space result above the baffle step. The two are spliced to give the final result. If I want polars I do that with the cab facing up by rotating the cab on either axis.

Sounds like an elegant way to do things. Will there be some ground reflection bouncing back up to the mic from the ground in the half space measurement?

[billfitzmaurice]

There would, below the baffle step frequency. That's why you discard that portion of the plot and use the ground plane result there. Alternatively you could dig a hole in the ground deep enough to place the baffle at ground level and back-fill around it, giving a one step half space result, but that's a lot more work. Roger Russell at McIntosh used that method, as it was far less expensive than building an anechoic chamber.