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Discussion Starter · #1 · (Edited)
Nominal spl @ 2.8vrms 1m = 85db. All measurements are taken unbaffled in free-air which explains the roughness in the response. The drop below 1khz is also due to the unbaffled loading. The yellow curve is good up until 1khz, for those interested in the low end performance. Note the 2 peaks at 5khz and 9khz, which are consistent in all the measurements. Excellent off-axis performance all the way out to 8khz.



Very clean decay.



Some serious energy storage issues at these frequencies.





Very clean waterfall. I suspect the ridge at 200hz and 500hz is the room.



All distortion measurements taken at 96dbspl at 1m. A fairly loud, real world listening level.

Poor performance at 100hz. Extremely high 3rd order and 2nd order distortion.



Better, but still somewhat high. For a less discerning ear/environment this would be a suitable highpass point.



Here would be a good point for a highpass ~1% distortion.



Excellent results at all the following frequencies < 1% distortion.






Overall, an excellent driver when used from 300hz and up. All the higher order distortion (nasty) products are very low in level, even at a full 96db. I'm very impressed.

Very nice BL curve. Almost perfect symmetry and flat, with smooth rolloffs on both sides. No wonder this driver had such low distortion. LE curve is also spectacular, probably due to the dual faraday rings in the motor. Kms looks good as well, with a slight forward bias.

This is a well built driver. 1 way xmax = 6mm.



Again, excellent quality control. T/S parameters are nearly spot on with manufacturer's specs.



Positives:

1. Very low distortion
2. Excellent linearity and well built all around

Negatives:

1. Rough upper end response both on and off-axis
2. Somewhat poor transient response
 

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man the peerless drivers are looking better and better lol

I jsut wish could fit the 5.5" mainly due to the higher sensitivity

and whats up with that 30 degree off axis? below 500hz

and hey my dang what other drivers are you testing??? just wondering if I need to hold on that pay now button :)
 
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Hi npdang,

Thanks for all the very useful data.

One thing though I'd like to point out: when the driver is not baffled the peak around 1800 Hz shows up, but when you do baffle it, the peak disappears. Stored energy measurements will reveal much better results.
 

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Which Audax are you referring to? PR170MO? On a side note how do the AP170MO fair in a car enviroment.

Crap! Just found out I bought the wrong ones. I thought I was getting the PRs..... :mad:
 

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What should be the upper limit on the response of the driver, as it looks 300hz up to how high....And how would this drivers response and detail be explained....or compaired to, as you (Dang) said it had somewhat poor transient response....Any ideal xover points for best results?
 
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demon2091tb said:
What should be the upper limit on the response of the driver, as it looks 300hz up to how high....And how would this drivers response and detail be explained....or compaired to, as you (Dang) said it had somewhat poor transient response....Any ideal xover points for best results?
As I already stated, the transient response of these drivers is just excellent! Do not measure them unbaffled because if you do you get unwanted resonances. The response when baffled is ruler flat and waterfall, transient response, is just top notch up to 3000 Hz!

You could also use the 830882.
4.2 dB more efficient and usable up to 3000 Hz. Very good distortion figures from 200 Hz up.
Below you see the 830882 close range measurement (mic in the plane of the surround) when put in my super duper resonant free enclosure. The waterfall depicts mainly the 2nd order highpass function of the closed box. The driver adds little. Breakup occurs at 4000 Hz but is well controlled and needs no special measures other then chosing the right combination of crossover frequency and slope.



 

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hey jeroen_d ive got the same mids im my kick panels of my rig, and for some reson they dont sound very good to me very grainy sounding in the higher feq. i dont know i cant explane it very well, it gets realy bad when your listning to hard rock like mudvayne and such :( . ive got them crossed at 200 6db and about 3.5k 18db no eq'ing or any thing.
 
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banginheep said:
hey jeroen_d ive got the same mids im my kick panels of my rig, and for some reson they dont sound very good to me very grainy sounding in the higher feq. i dont know i cant explane it very well, it gets realy bad when your listning to hard rock like mudvayne and such :( . ive got them crossed at 200 6db and about 3.5k 18db no eq'ing or any thing.
What is the volume of enclosure? If they are not put in a small closed box, 6 dB/oct at 200 Hz will severely stress the driver if played loud with hard rock. After all they only have a surface of 53 cm2.
 
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Anyway, 6 dB at 200 Hz is not recommended. I would say cross them at 240 Hz minimum and with 12 dB/oct. To play really loud, stick to the recommended 300 Hz by npdang.

Listen to the midwoofer without the tweeter to check if it is really the mid. Bad integration with the tweeter can let the system sound harsh. Ofcourse I don't know anything about your crossover skills, so this advice could sound a little bit disrespectful. If so, I'm sorry for that.
 
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