Another Full Range 3" Driver question (Dayton ND90-8 vs. Aura NS3)

[981CS]

I've found conflicting information about these two drivers (Dayton ND90-8 vs. Aura NS3). I thought they were exactly the same, but I've been told that the Dayton version is more of a "copy" and not the exact same thing as the Aura.

I can find the Aura in stock (the 4 ohm version at least) but now I'm wondering how well that will work with the notch filter that Carmody spec'd out for his 4 ohm sprite. Anyone used both of them? I've used the Dayton 4 ohm version, but never the Aura 4 ohm.

[Chris Roemer]

The ND90s MIGHT have "similar" 8ohm and 4ohm versions, but there really is no 4ohm AURA "equivalent" to the 8ohm NS3-193-81A (which Dayton's ND90-8 "appears" to be based on).

[LOUT]

Does that mean the 4ohm Aura that 981CS is seeing "in stock" is probably a different style/model which isn't really comparable?

[LOUT]

Their specsheet claims look pretty similar in a lot of places, but they also have some differences that I'm unsure whether or not they could be measurement errors or manufacturing quality/drift or if they're pretty constant differences.
https://www.parts-express.com/pedocs...on%20Sheet.pdf
https://www.parts-express.com/pedocs...ifications.pdf

Comparing the 8ohm versions' specs, it looks like the impendance slope is very similar and the largest frequency peak (~+5db around 7.5-8Khz) is also pretty similar, but the rest of the measured frequency response supposedly has some differences...so I'm guessing a notch filter that gives some BaffleStepComp or something that tames that peak should work for either (assuming the 4ohm versions are like this and the notch is designed for them). But I think anything more specific that needs to be really precise might lose something in translation between the two brands.

[981CS]

The one I see in stock is at madisound.

Aurasound NS3-193-4A1 3" Full Range, Black Cone, * 4 ohm *

So is this not an "equivalent" to the ND90-4?


Appreciate the help on this as I'm definitely not sure of the history of these drivers.

[Chris Roemer]

Well, your 4ohm NS3 (at ms) DOES look at LEAST as comparable to the 8ohm AURA as the 4n(ohm) Dayton looks to IT's "cousin" - from a box model perspective.
If you really want a 4n system, and you want the less expensive driver (AURA vs ND90), and your ? is whether Paul's 4n filter will be appropriate for the AURA, then I can look at that for you.

I've never (personally) used the ND90s (or 91s), but I HAVE used the ND65s and the 105s (I think they're great).
My "piconeo" project (10 yrs ago?) DID use the 8n NS3 (unfilterd) in a 0.15cf vented box. for a pretty impressive (bass-wise) "desktop" build, back in the day.
Today I'm using some 2-ways (old morel mdt-44 tweeters) using Dayton's TCP115-4 in a vented 0.10cf box. Nicer. Strong bass to 40Hz (on the desktop) even though WinISD (and my OWN DATS measurements) shows them pooping out closer to 50. Pleasant surprise.

[Whitneyville1]

The Dayton ND91's are a little different beasts than the Aura NS3's in both the 8 ohm and 4 ohm versions. The Dayton ND90 is closer to the Aura NS3 8 ohm than the Dayton ND91. To me, the Aura NS3-8 with a very simple resistor "notch filter" run full range sounds very, very good. To go insane, put an XO and an ND20 or ND28 tweeter on top and have a super desktop computer monitor speaker. The 4 ohm versions of ALL these speakers are just enough different to be different. They sound a little different, with a little less bass.

[981CS]

If I had to pick I'd just buy the Dayton ND90-8 and be done with it as I know Carmody's filter is simple and effective on that driver. But, I'm running out of time and the only version I can find in stock is the Aura NS3 in 4 ohms.

If it is different enough to where Carmody's filter for the Dayton ND90-4 needs to be redesigned...I'm not sure I have that kind of time. If you want to give me an opinion of if it'd work I am willing to try. I just don't want to lose the bass that little driver is capable of (not to mention very decent mids as well and not horrible at highs).

It is interesting that the ND90-8 has better bass than the ND90-4. I had not noticed that.

[LOUT]

I think the 8ohm versions of speakers usually have slightly lower Fs and can reach slightly deeper bass compared to their 4ohm sisters...but I don't think the end result is nightVSday (that's just a guess though).

[jhollander]

I have at least 2 different versions of the ND90s and also the ND91's so somewhere along the way PE changed the supplier and specs. If Chris would look at the notch with the 4 ohm that's probably your best bet. I can't swear to it but I recall my 4 ohm modeled better F3 than the 8 ohm

[Chris Roemer]

The FR plots of the 4ohm vers. looks sig. different above about 4kHz.
Paul's "soft notch" on the ND90 depresses the area around 2k (mainly).
For the AURA 4ohm you don't need as much depression (since it looks "flatter") and I'd drop the target area down to maybe 1k?

Try Paul's 3-el filter (for the AURA) but substitute 2ohms (for the 6ohm resistor) and try 33uF (for the 8.2uF cap).
You can't really duplicate the ND90's FR w/a simple filter on the AURA, but I think this will get you closer than the ND90 filter.
Let us know how it goes.