Hivi B2S as tweeters?

[gainphile]

How good are they as tweeters, let say 1kHz - 20kHz?

Any experience ?

[sreten]

Hi,

At 78dB sensitivity suited to mating with a very small "subwoofer".

http://www.linkwitzlab.com/Pluto/intro.htm

/sreten.

[holdent]

[Disclosure - I haven't used this driver!]

The sample response graph provided by PartsExpress (http://www.parts-express.com/pdf/297-432.pdf) looks pretty rough (the manufacturer's spl curves appear to be "optimistic"). At 78 (2.83v/1m)(dB) its sensitivity is very low. You'd likely end up spending more time and money trying to tame this curve than it would be worth.

Why not go with the actual 2" driver used in the Pluto - the AURA NSW2-326-8A? Or try the larger HiVi B3N 3" driver? Both have got excellent reviews and are more sensitive. The B3N is about the same price but the Aura is about $8 more each.

What application were you thinking of using this for?

[gainphile]

Basically this is the situation: I am using Vifa TC20 for OB speakers and a no-name brand for the rear firing tweeters. Crossed at 1.5kHz and audibly strained as the Fs of these drivers are 1.5kHz. Now, this is temporary until I can get something more decent, but low-Fs tweeters are quite expensive and will easily se me back $250 for 4 of them (Vifa DX27, etc.)

I have the Pluto so NSW2 is on hand. I also like it's sound I think they are very detailed and smooth. But not convinced that would be great for OB as the rear chamber acts like pipe. Looking at B2S, it has similiar radiating area as NSW2 and a "normal" loudspeaker shape. As they are opened-back it would eliminate the need of rear-firing tweeterst too as a bonus.

I guess I just have to try them for $30 a pair ... was hoping that someone has done the task . I'm not convinced with the high frequency resolution of 3" FR. I got Tangband which rates better at Zaph site compared to B3N and they're not great nor detailed like proper tweeters.

[a_tewinkel]

How about a Tangband W2-800SF? It has good sensitivity (87 dB) and response up to 20 kHz.

[planet10]

Originally posted by gainphile
I'm not convinced with the high frequency resolution of 3" FR.

Fostex FF85K* makes a really good tweeter. I'm listening to a pair XOed at~333 Hz as we speak.

*(have to admit i haven't listened to a stock one yet)

dave

[Stuey]

Hi gainphile,

I've used the B3S in a similar speaker to Zaph's (same filtering, slightly smaller box) and you're right, it doesn't have the same detail up high as a proper tweeter.

In my case, nice for the application, though, as a non-fatiguing (near field of course) bedside speaker. Detailed enough close up.

Cheers

Stuey

[gainphile]

Thanks all for the ideas. It seems like 3" is the maximum size of "possible tweeters". I will try to use my NSW2 on OB and will report tonight...

If that didn't work then the only way is to invest on normal dome tweeters with low Fs.

[gainphile]

It turns out that the Aura NSW2 used in Plutos are good for OB.



These are open-backed so ideal for dipole speakers. Front near-field measurement is similiar to the datasheet. But my worry on pipe resonance from the rear is real. This is what measures nearfield from the back (ignore the absolute SPL level, they are uncalibrated).



Measured from the farfield (80-100cm) this resonance has the influence on the summed dipole signals.



Equalization value for the notch filter is easily calculated. Fs=1.6kHz, Q=3, depth=-8.5dB. Using software parametric equalizer and pink noise this is the equalised response:




Frequency response of NSW2 is limited to around 15kHz. I feel it lacks the extreme sparkles (tymphany, etc). But what is gained from these tweeters are extreme 'cleanliness' of midrange sound. Must be the pistonic property of titanium cone. I notice guitars and female voice are extremely good. Cymbals are ok but not great.

I think it's a keeper but let's wait for a week or so. Tomorrow off to jaycar to build the analog notch

[Stuey]

Hardly in the same class I think, but my impressions of the B3S are similar.

It has an alum/magnesium cone which gives that cleanness in the mids, such as with cow bells, guitar, and fem. voice. Best part about this speaker, in fact.

Surprisingly, they give me a lot of enjoyment listening to good FM radio.

Stuey