AURA NS3-193-A81 & my WT3

[Chris Roemer]

These arrived from ms in about 2 days. I got the black ones. Total cost ran about $16 each. Break-in just consisted of pushing back and forth to near Xmech a few times with my fingers. Used 30g added mass. Pe 20w. Sd about 4.7 sq.in. Values are average of 2 test units.

parm/spec/preBI/postBI

Re .../ 7.6 / 7.4 / 7.4
Fs .../ 80 ./ 93 ./ 84
Qes ./ .73 / .90 / .80
Qms / 8.0 / 5.8 / 5.2
Qts ./ .67 / .78 / .69
Vas ./.044/.027/.035
Le .../ . . / 1.13/ 1.12
Mms / 4.3/ 4.6 / 4.4

Fs comes down pretty close to spec after exercising the suspension.
Qms not even close to spec. Curious.
Qts also close to spec. post break-in.
As Qts comes down, if Fs also drops, and Vas rises, box model doesn't change appreciably.

'Night.

Chris

[Whitneyville1]

Re: AURA NS3-193-A81 & my WT3

Thanks Chris. I'll plug you numbers into WinISD and recalculate my speakers and see what "answers" I get. The lack of Le #'s made me wonder. The "specs" are enough off of your measurements that my calculations may be contributing to my "issues".

[PWR RYD]

Re: AURA NS3-193-A81 & my WT3

I suspect that after more break in the values for Fs, Qts, and Vas will approach published specs. I can't explain what's going on with the Qes and Qms though.

[Chris Roemer]

Re: AURA NS3-193-A81 & my WT3

I suspect that after more break in the values for Fs, Qts, and Vas will approach published specs. I can't explain what's going on with the Qes and Qms though.

Qts is calculated from Qes and Qms:

Qts = (Qes x Qms) / (Qes+Qms)

As it turns out, Qes has a lot more to due with Qts than Qms (has to do with Qts).

The NS6 woofers I got from PE were WAY OFF "spec", even after break-in, requiring a box nearly double the size the the specs indicated (not good).

I wonder how Curt's measured?

[PWR RYD]

Re: AURA NS3-193-A81 & my WT3

I think you mean Qts has a lot more to do with Qes than Qms ;)

[lostboy77]

Re: AURA NS3-193-A81 & my WT3

What are you planning to do with the NS3s?

[Chris Roemer]

Re: AURA NS3-193-A81 & my WT3

What are you planning to do with the NS3s?

Why, Pico Neos of course!

0.15 cf about 11"h x 5"w x 9"d witha 1.25"d x 7" long vent.
Like to run the pair off the Lepai amp.

[its_bacon12]

Re: AURA NS3-193-A81 & my WT3

Why not break them in off some old radio alarm speaker output on static (white noise) overnight?

[dthomas]

Re: AURA NS3-193-A81 & my WT3

These arrived from ms in about 2 days. I got the black ones. Total cost ran about $16 each. Break-in just consisted of pushing back and forth to near Xmech a few times with my fingers. Used 30g added mass. Pe 20w. Sd about 4.7 sq.in. Values are average of 2 test units.

parm/spec/preBI/postBI

Re .../ 7.6 / 7.4 / 7.4
Fs .../ 80 ./ 93 ./ 84
Qes ./ .73 / .90 / .80
Qms / 8.0 / 5.8 / 5.2
Qts ./ .67 / .78 / .69
Vas ./.044/.027/.035
Le .../ . . / 1.13/ 1.12
Mms / 4.3/ 4.6 / 4.4

Fs comes down pretty close to spec after exercising the suspension.
Qms not even close to spec. Curious.
Qts also close to spec. post break-in.
As Qts comes down, if Fs also drops, and Vas rises, box model doesn't change appreciably.

'Night.

Chris

Le looks high for such a small voice coil. Have you calibrated your woofer tester in a while?

[Chris Roemer]

Re: AURA NS3-193-A81 & my WT3

Le looks high for such a small voice coil. Have you calibrated your woofer tester in a while?

They ARE four layer coils.

[lostboy77]

Re: AURA NS3-193-A81 & my WT3

Why, Pico Neos of course!

0.15 cf about 11"h x 5"w x 9"d witha 1.25"d x 7" long vent.
Like to run the pair off the Lepai amp.

I've built a pair of those using the ND90-8 only mine were a little larger and tuned a little lower. I preference is (and what I am running now) is a little smaller (1.25 cf) with a little higher tuning (57Hz rather than 53). This provides 2-3db rise from about 200Hz down which helps with the lack of a BSC. If I were running these on/near wall or strictly near field, then I would go with your option for better bass extension. Amazing little drivers really.

[Whitneyville1]

Re: AURA NS3-193-A81 & my WT3

From the Tech Boys at PE, the ND90's are supposed to be more like the earlier NS3's (Le~.54). The ND91's are supposed to be an improved NS3, but WinISD doesn't show that much improvement. Chris' data shows the "evil fish hook" below 60 Hz tuning in almost any size enclosure with the Aura NS3's. My great plans for a "high pass cap" on my NS3's at ~50-55Hz doesn't look promising as it's too close to Wolf's 500uF NPN he used on his PC Speakers. I can help "fix" the unwanted sub 50Hz response with the EQ function in the 'puter-thingey, but I had hoped to do it passively or acoustically. I guess the humps and dips above 6.5KHz are part of living with an aluminum driver's break-up in it's top 3 octaves. Any of the wise men of taming this driver design, would an ~9.3 Ohm/10-13mf Zobel network be worth the $1 price tag and effort?

[Chris Roemer]

Re: AURA NS3-193-A81 & my WT3

From the Tech Boys at PE, the ND90's are supposed to be more like the earlier NS3's (Le~.54). The ND91's are supposed to be an improved NS3, but WinISD doesn't show that much improvement. Chris' data shows the "evil fish hook" below 60 Hz tuning in almost any size enclosure with the Aura NS3's. My great plans for a "high pass cap" on my NS3's at ~50-55Hz doesn't look promising as it's too close to Wolf's 500uF NPN he used on his PC Speakers. I can help "fix" the unwanted sub 50Hz response with the EQ function in the 'puter-thingey, but I had hoped to do it passively or acoustically. I guess the humps and dips above 6.5KHz are part of living with an aluminum driver's break-up in it's top 3 octaves. Any of the wise men of taming this driver design, would an ~9.3 Ohm/10-13mf Zobel network be worth the $1 price tag and effort?

If you use any kind of XO modeling software, you'll see that parallelling a woofer with a Zobel has absolutely no effect on the driver's response whatsoever. All it does, is flattens the impedance rise above Zmin, so that any low pass components (out ahead of the Zobelled woofer) work in a more predictable way.

[Whitneyville1]

Re: AURA NS3-193-A81 & my WT3

I thought that was correct, except it reduced the impedence "zoom" on a given driver. I'd like to find a good small cheap tweeter to handle 5K-20K with the NS3 small for phasing, cheap because I want to keep the cost down. Very tough combination. I'm hoping Santa will bring me a WT3 for Christmas, and just maybe some active measurement stuff (poor man's Omni-Mic).

[Chris Roemer]

Re: AURA NS3-193-A81 & my WT3

I thought that was correct, except it reduced the impedence "zoom" on a given driver. I'd like to find a good small cheap tweeter to handle 5K-20K with the NS3 small for phasing, cheap because I want to keep the cost down. Very tough combination. I'm hoping Santa will bring me a WT3 for Christmas, and just maybe some active measurement stuff (poor man's Omni-Mic).

Crossing at 5k means you've got to find a tweeter that's <= 1.9"OD.
Part # 275-030 fills the bill. Too bad they just went up $10 a pop.
The 264-1024 tweeter is slightly taller. At 2.1", 5k is just a tad over the edge for that one, 4k would make more sense.