In fact it was talked here.
The non L is used by some and you can see it in the SB12.3 open source kit (Zaph). It goes flater deeper but needs more volume box sealed than the L version (around 50 liters iirc for a 0.5 Qtc which could be overdamped perhaps. Higher Q makes the volume climbing)
The L version migth needs to be EQ, however limiting exursion in the low end. Or doubled in the cabinet as some made already.
I have no souvenir though of a L version talked with one of the passive radiator from SB Acoustics.
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The non L is used by some and you can see it in the SB12.3 open source kit (Zaph). It goes flater deeper but needs more volume box sealed than the L version (around 50 liters iirc for a 0.5 Qtc which could be overdamped perhaps. Higher Q makes the volume climbing)
The L version migth needs to be EQ, however limiting exursion in the low end. Or doubled in the cabinet as some made already.
I have no souvenir though of a L version talked with one of the passive radiator from SB Acoustics.
.
Unfortunately SB34NRX75L-8 is not designed for sealed but for BR or Transmission line.
Only one project SB12.3 Zaph. Very strange for such good driver.
Only one project SB12.3 Zaph. Very strange for such good driver.
This may be of interest. Here is the near field measurement of an SB34NRX75-6 in a 70 liter sealed box. The solid black line is the un-altered near field, which represents a 2-pi half space response. The dash blue line is modified to represent the 4-pi full space response.
I use this driver as a woofer with a 200 Hz crossover. The NF response peaks at 75 Hz, and is about 5.5 dB higher than the 300 Hz level. This means the driver needs very little (or none) baffle step compensation. In my application, I apply some bass EQ to get a flat response down to 30 Hz.
j.
I use this driver as a woofer with a 200 Hz crossover. The NF response peaks at 75 Hz, and is about 5.5 dB higher than the 300 Hz level. This means the driver needs very little (or none) baffle step compensation. In my application, I apply some bass EQ to get a flat response down to 30 Hz.
j.
Yes specs/features mentions that, but did you try simulate it in sealed?
Here is simple sim in 60 sealed with/without light Linkwitz transform. At 95dB with LT still 10dB headroom.
(If my sim in VCad is right)
The Non L version in same 60 Liter without LT (changed input power a little to show same SPL)
No I didn't try because of low qts. But I will try to simulate. I believe that driver is good but strange is that is not more involved in diy projects.
What you cant see from the graphs is how the thing sound. From my memory most/everyone on DIY pointed the L version as the much better choice. It is a bit more expensive (both drivers are not cheap), but you get 1.5 kg more magnets, dual shorting rings etc.
Maybe simple answer is the L version is a better driver.
Maybe simple answer is the L version is a better driver.
I think the SB34NRX75-6 would be a fine driver in a 3-way system, crossing at 300 Hz or lower. Passive crossovers at 300 Hz are big and expensive. One option is to use an active crossover for the low frequency (in the 200 - 300 Hz range), and then use a passive crossover from mid to tweeter. Use one amp for the woofer, and another amp for the mid-tweeter.
But "big and expensive" is relative. Many people have designed and built passive crossovers in the 200 - 300 Hz range.
But "big and expensive" is relative. Many people have designed and built passive crossovers in the 200 - 300 Hz range.
Here if I take the same LT than @Rokytheman in 57l ( qtc 0.58 ) for the L version plus a low pass 12 dB around 250 hz acoustical (-6dB). show the impedance selected.
in 4Pi space : the max spl at 2.83V is 85.6 dB (numbers on the graph are the brown 4Pi curve).
in 4Pi space : the max spl at 2.83V is 85.6 dB (numbers on the graph are the brown 4Pi curve).
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