Looks like SB has new drivers

[LING GOWA]

Just checked the SB site to find they have some new drivers, 8'', 4'' and a new tweeter.
Maybe someone here can help me understand why such low power handling.
60 watts from an 8'' driver is not very impressive.

[Jed]

They both look promising to me. I think they used the lower distortion motor on the 8" driver as well. The 8" has plenty of Xmax to play loud- 6.5mm. I see they are using Seas' p-p method to make it look like the driver has more Xmax for the casual observer.

The 4" looks nice. Can't wait to try it. They might find a home in a new Lineup Series I'm planning.

Jed

[Curt C]

Just checked the SB site to find they have some new drivers, 8'', 4'' and a new tweeter.
Maybe someone here can help me understand why such low power handling.
60 watts from an 8'' driver is not very impressive.

Correction: This post refers to the SB17NRX. I grabbed the wrong driver file by mistake... The comments made here are correct for the 17, and the SB23 are posted down thread... I added the SB17 response and excursion plots here as well.

Power handling is in many cases a non-issue, as the driver in question will reach its excursion limits far before it will reach its thermal (power) limitations. Drivers have to be modeled to determine their actual max SPL.

I calculated the sealed and vented excursion limited power levels of the SB23NRXS45-8, roughly designated as that point cone excursion achieves 115% Xmax, as shown below:

Sealed: Q 0.7 16 liter enclosure f3 65 Hz
Requires 17 watts for 7.5 mm excursion 30 Hz SPL 100 dB

Vented: 20 liter enclosure tuned to 30 Hz f3 47 Hz
Requires 25 watts for 7.5 mm excursion at 50 Hz SPL 102 dB

C

[Jed]

What does the response look like in more volume Curt?

[LING GOWA]

I'm just not sure who they are trying to target with this type of 8'' driver. I also see it as merely average. I wonder what price point they intend for this one. What's with the crazyness after 900 Hz?
The 4'' does look promising. It may find a place now that the Vifa PL11MH09-08 is no longer available. It'll be interesting to see what Jed comes up with.

[Jed]

I think what Curt was implying was the power handling is not lower than average for this size driver. The 8" driver may not be good for a 2 way but will work fine for most applications in a 3-way where a crossover of 400-500hz is often utilized.

[Operandi]

The 4" looks nice. Can't wait to try it. They might find a home in a new Lineup Series I'm planning.

To replace the W4-1337?

If so thats saying quite a bit right there.

[Jed]

To replace the W4-1337?

If so thats saying quite a bit right there.

Can't say until I get some end of January to test and listen to.

[Curt C]

What does the response look like in more volume Curt?

The better question Jed, would be: What would the response look like if I had chosen the correct driver to model? ops:

Above is for the SB17NRX, and gee, for a 6.5" driver, they look pretty good. I stand corrected...

OK, HERE is the SB23NRX, and yes, they look much better:

Sealed: Q 0.7 50 liter enclosure f3/f10 48/28 Hz
Requires 17 watts for 7.5 mm excursion at 30 Hz SPL 101 dB

Vented: QB3 tuning 75 liter enclosure tuned to 28 Hz f3/f10 29/21 Hz
Requires 27 watts for 7.5 mm excursion at 41 Hz and SPL of 103 dB

Vented: Lower Q tuning 75 liter enclosure tuned to 24 Hz f3/f10 30/20 Hz
Requires 23 watts for 7.5 mm excursion at 37 Hz and SPL of 102 dB

Response and excursion plots below.

They still don't need 60 watts for full excursion, tho...


C

[Operandi]

Can't say until I get some end of January to test and listen to.

Cool, looking forward to the results.