Measuring subwoofer TS params

icbcodc

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Hello John, how is it going?

I got a JL 12 inch subwoofer (12W3V3-4), and I'm making a enclosure with a port according to the data (size) provided by JL for this subwoofer.

But there is no fill information for this enclosure , I don't know whether I should fill some glassfibre into the enclosure.

So I'd like to test the T/S parameter of this SUBWOOFER, but I don't have a suitable holder to make it vertical, can I measure it horizontally like this:

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John Mulcahy

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The results would be affected by the orientation, though I don't know how large the effect would be. An alternative might be to measure the performance when it is installed in its enclosure and see if the fill produces a result closer to what you are looking for, or ask JL what they recommend.
 

icbcodc

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The results would be affected by the orientation, though I don't know how large the effect would be. An alternative might be to measure the performance when it is installed in its enclosure and see if the fill produces a result closer to what you are looking for, or ask JL what they recommend.
Thank you , John

Could you help me to align the phase for woofer and subwoofer using REW?

I found the size information for its enclosure from JL website and made a enclosure.

I tried to align the phase for subwoofer and front speakers in a Benz E300L with the REW sweep file for measurement including timing ref,but failed.

I used 3 way speakers for the front audio system with half active crossover in this car. That means the mid-range speaker and the tweeter are in one way,the woofer is in the other way.

The subwoofer of JL is in another way.

Now I would like to align the phase for subwoofer ,mid-range speaker and tweeter.

Because the timing ref audio is played from mid-range speakers,when I measured the phase of subwoofer,I had to play the front mid-range speakers with subwoofer together.

When I measured the phase of front woofer,I also had to played the timing ref audio from front mid-range speakers.

Then I get two phase cures from the subwoofer(mid-range) and woofer, and I knew the woofer need to be delayed, then I delayed the woofer,but the tweeter and mid were not delayed,new phase of the woofer would not change.

Should I delay the mid-tweeter speakers and woofer together? then made a new measurment and compare the phase of the woofer with that of the subwoofer?


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John Mulcahy

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You should play the timing reference signal from the side you are not adjusting. For example, if you want to adjust delays for the right side drivers, send the timing signal to the left side.
 

icbcodc

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You should play the timing reference signal from the side you are not adjusting. For example, if you want to adjust delays for the right side drivers, send the timing signal to the left side.
Hello John

I played the timing reference signal from the left sied tweeter only, and measure the subwoofer and the right woofer phase seperatedly, but there is an error message :

42676


Something wrong!
 

John Mulcahy

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I don't see any error messages or problems with that file. It does not seem to have the particular measurements that were in your screenshot, though they are very similar. Do you still get the error message? When does it appear?
 

icbcodc

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I don't see any error messages or problems with that file. It does not seem to have the particular measurements that were in your screenshot, though they are very similar. Do you still get the error message? When does it appear?
Yes, I measured again today, but when I pressed the "Align phase at cursor" button , I got the same error message.:mad:

You can try it.
 

John Mulcahy

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I think I see how that can happen. Please tick the box "Show phase traces" and the error message should stop appearing. You do not have to leave the box ticked if it makes the graph difficult to read.
 

icbcodc

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I think I see how that can happen. Please tick the box "Show phase traces" and the error message should stop appearing. You do not have to leave the box ticked if it makes the graph difficult to read.
Cool! Thank you very much.

But I think the tab should be mandatory before pressing the Align phase at cursor, cause information is there already, just not shown.

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