My Current Project...(Teasers...)

[Wolf]

It's likely the 'chamber' they have at PE.

It's basically a booth like you get into at the ENT for hearing tests, or for recording vocals. They have added the wedges to the walls, and the former window is the mic/driver interface depending on the function intended.

Later,
Wolf

[mattp]

Nice anechoic chamber. So the graph above was in the chamber? Any gating? I'd love to see some detailed pics about the chamber so we could diy one...

It's likely the 'chamber' they have at PE.

It's basically a booth like you get into at the ENT for hearing tests, or for recording vocals. They have added the wedges to the walls, and the former window is the mic/driver interface depending on the function intended.

Later,
Wolf

Ben is correct, this is the chamber here in the lab at PE. Not so much a booth but an actual room (~1500 cuft) with a non treated floor. It's good to around 450 Hz and yes that distortion was gated at 5ms. We usually blend our FR curves for spec sheets around 500-600 Hz. The tweeter for this test was about 61" off the floor on two stands stacked.

I have attached frd and zma files for anyone who wants to fiddle. Everything is 2.83V/1m, woofer is blended to nearfield at about 720 Hz.

Epique Woofer.zma
TL Tweeter.zma
Woofer 0deg.frd
Tweeter 0deg.frd

[jhollander]

Nice, might play if you have the T+W file...

[mattp]

Nice, might play if you have the T+W file...

Sorry John, if you are asking for a different file than I posted I'm not sure what that would be. Can you elaborate?

[jhollander]

Matt I would need the T+W file to be able to find the offsets between the drivers.

[JoeCaWWW]

Wow! That's awesome, man!

[Wolf]

That's bigger than it used to be then.
Wolf

[Vader540is]

Beautiful work.

[rpb]

Ben is correct, this is the chamber here in the lab at PE. Not so much a booth but an actual room (~1500 cuft) with a non treated floor. It's good to around 450 Hz and yes that distortion was gated at 5ms. We usually blend our FR curves for spec sheets around 500-600 Hz. The tweeter for this test was about 61" off the floor on two stands stacked.

I have attached frd and zma files for anyone who wants to fiddle. Everything is 2.83V/1m, woofer is blended to nearfield at about 720 Hz.

[ATTACH]n1419249[/ATTACH]
[ATTACH]n1419250[/ATTACH]
[ATTACH]n1419251[/ATTACH]
[ATTACH]n1419252[/ATTACH]

This was fun playing with. My x-over uses a lot of parts to smooth some bumps. Probably isn't practical, but If you like big x-overs.....

[mattp]

Quick question for anyone who has used TL N26CR2-A tweeters in the past (I don't think there are many...)

Due to the peak in the woofer, in order to get away with a minimal-component XO with no notch these really want to be crossed around 1300 Hz second order. Is this a safe XO for these tweeters? My listening tests don't show any real strain even at higher levels but I know these are fragile and I realllllly don't want to literally break one.

John Hollander has been graciously helping me get these as good as I can get and proposed asking anyone that has used them before. Here is the first sim he came up with. I have only listened to this one so far. I do not see any issues in the distortion plots at all... and nothing is shouting at me during listening tests.

[mattp]

Actual measurements. Distortion was taken at 5v with 1/24 smoothing.


Top is overall, bottom is tweeter only with XO.

[mattp]

For anyone curious this is 0-45 degrees.

[mattp]

Since I cannot edit my other post...here is overall measured with individual driver roll-offs.

[Wolf]

I would still likely place an LC across the woofer and see if you can't get to -50dB on the breakup. As low HD and resolving these should be, I would remove all doubt and kill that blemish. This also might allow you to shift the xover higher, as I think Xmax could be your issue, not HD. I would try some higher output with xover and see, but 1500+ w/o waveguide is probably recommended. I have a set of TL, but not that model.
Wolf

[Wolf]

And a cap of about 1uF across your padding resistor will lift the top.
Wolf