NEW Nirvana Super15 Alnico FullRange Driver

[FullRangeMan]

Good News! There is a new big 15 inches ALNICO fullrange driver on the NIRVANA site; no price info yet.
The image on the datasheet is not good unfortunately.
Gustavo
http://www.commonsenseaudio.com/an15alnicospecs.jpg

 

[Godzilla]

Qts .95 is a good candidate for open baffle. A small super tweeter (hidden in plain sight) on a large baffle would complete an interesting speaker. It might look like just another knot on the wood. Surprising only 91db per watt tho... but that offers bass extension. I think it's cool.

 

[Scott L]

specs ?

Take a look att the Xmax... a whopping 1mm

Next, look at the impedance plot vs what's listed as Fs.

Fs is listed as 28.5 and the graph shows 45.

 

[Bob Brines]

Take a look att the Xmax... a whopping 1mm

Next, look at the impedance plot vs what's listed as Fs.

Fs is listed as 28.5 and the graph shows 45.

This is just a guess, but it appears to me that the plots shown are in some sort of box. There appears to be baffle hump, and the roll off starts way too low for anything that approaches a standard baffle. Of course, with a Vas of almost 500L, an infinite baffle needs to be near, well, infinite! DD might want to state his test conditions.

Bob

 

[Scottmoose]

The image on the datasheet is not good unfortunately.

You're not kidding. As per usual with Audio Nirvana, their data sheet appears to be self-contradictory. Take Vas for e.g. Assuming the electrical specs. are true, then the quoted ~493 litres is way off & something around 400 litres would be more like it (I make it 406). Or visa versa.

Yep, looks that way to me too Bob. -3dB Fhm should be around 45Hz from the stated Qe & Fs, but it's lifted into an elevated plateau at almost exactly that point.

The impedance graph looks like it agrees with the claimed Fs though to me -it's in 5Hz increments in the LF.

 

[GM]

Fs is listed as 28.5 and the graph shows 45.

Use SlowView or similar, its impedance peak plot is near enough to 28.5 Hz for me, though of course what one gets may be somewhat different, same as with too many manufacturers unfortunately.

GM

 

[GM]

Take Vas for e.g. Assuming the electrical specs. are true..........

Well, FWIW, I ran the numbers and by altering Sd to 800 L I get near enough to spot on Mms, BL down to two decimal places using the published Fs, Vas, Qes, so for now I'm going with the effective radius being closer to 15.96 cm which seems reasonable to me considering the frame size and small VC diameter.

GM

 

[Scottmoose]

Ah, that sounds favourite. Still doesn't exactly inspire confidence, when you've still got to adjust part of the data for the rest to make sense.

 

[GM]

Yeah, and one reason why I don't promote them.

GM

 

[Scottmoose]

That's two of us. If I was in the market for a big driver, I'd rather get a good pro unit or preferably save a few months longer & put it towards one of GPA's 604s or 212s.

 

[FullRangeMan]

The price info are avaliable, is $999 per pair.
Gustavo

 

[Scott L]

I'm either crazy, or need new glasses

Use SlowView or similar, its impedance peak plot is near enough to 28.5 Hz for me, though of course what one gets may be somewhat different, same as with too many manufacturers unfortunately.

GM

Sure looks okay this time around... I don't know what I was looking at last time ? I sure do apologize.

 

[GM]

No biggie, they just use a higher definition plot than most manufacturers, so good on them for that, i.e. you 'saw' what you expected to 'see' from experience.

GM

 

[FullRangeMan]

New image from the Super15Alnico, looks good...

An externally hosted image should be here but it was not working when we last tested it.

 

[Democles902]

What did you decide to do?
I was thinking of making an open baffle speaker and either use a large full range or coaxial but it sure is hard finding one with a high qts high x-max and low fs. Darn near impossible.
What to do?