i personally think they just make something that's good enough to be loud/have decent directivity and have good low frequency extension, then look for ways to make the speaker "musical" with random bumps here and there that will be smoothed out by 20k dollar tube amps which are load dependent or something
Do you believe that "cancelling" technologies like DBA or ART will be the solution?
that's weird, most people i've seen with esoteric setups have either tubes or "musical" amps.Every B&W speaker I’ve ever seen in a store has been demoed with solid state amplification, and I’ve seen very few B&W speakers in audiophile set ups powered by tube amps.
I think it’s very likely they design in a way that to their ears makes a speaker “ disappear” and has to their mind a vivid sonic signature they feel sound more life-like.
From what I’ve seen most speaker designers are quite passionate (or at least started it out that way) and really have specific goals in mind. Some speaker designers obviously have wonkier methods, or goals not aligned with strict neutrality. Forbetteror worse.
marketing speak, they just want to make something that catches the ears of a listener and neutral is "boring"/"sterile".
still a business at the end of the day so i wonder if the marketing team has some input for them or the target consumer's preference (bright "detailed" signature) might influence them or something, and if the designer is genuinely passionate about making shit then more power to them ig. They still sell well from what I can see. Good business at the end of the day
A loss of £8 million after tax isn't what I'd call successful.basically more marketing speak for people who are easy to fool with sweet words. He's a rep, not an engineer, his job is to make the product appealing to the target consumers to stimulate demand and he's doing that successfully
I think you misread the post. He was saying the sales representative was successfully stimulating demand in the original poster.
If he's successfully stimulating demand surely they would be profitable? I'm sure he's stimulating some sales but clearly not enough.
Come on, you know the answer to this. No need to double down. Stimulating demand in one person with marketing poetry does not mean a company is profitable.
I reduced the gain 9dB for the measurements without the L-pad.
. So whatever drawbacks, I think are offset by other tradeoffs.
A few things come to mind.
The L-pad smooths out the driver's impedance peak.
Here is the impedance of a D2 driver mounted in it's lens with no filter (blue), the L-pad only (red), and the complete network (green):
View attachment 508336
Some amps may become unstable with this high impedance.
The impedance resonances do change the frequency response which could be addressed in the DSP filters.
View attachment 508357
But the L-pad appears to be damping the resonances seen in the impedance curve, especially in the red trace where I drive the speaker with only the 8 uF filter capacitor and no L-pad. You can see in the red trace the impedance peaks are interacting with the filter capacitor and making additional response unevenness with higher peak at 600-700 Hz, lower trough at 800-900 Hz, and a larger ripple in the 1-2 kHz region. This translates to less filter EQ needed to get to the desired response. Those closely-spaced ripples are hard to EQ. The cost is 9 dB less voltage sensitivity, which in the case of this driver is actually an advantage for me since it plays absolutely terrifying SPL with just a few Watts.
The impedance resonance anomalies are often best removed at the source in my simple experience, although am not an expert on resonances in non-linear systems. I do see a spike in 2nd HD at 600-700 Hz with the 8 uF capacitor, but it really isn't dramatic. I would be interesting if Dr. Toole or maybe @Frank Dernie have comments or considerations about damping these resonances with the L-pad.
View attachment 508369
This is no big deal on distortion, even if we can see a spike. Perhaps at higher SPL this becomes more dramatic due to nonlinear behavior of these resonances, JBL likely have data but out of self-reservation I won't test that loud!
Thatt 9 dB reduction in sensitivty can be an advatage, the network reduces audible noise allowing the driver to be powered by a range of amplifiers even with elevated noise specs. I actually compared the noise of the driver with and without the passive crossover across a range of amplifiers; PuriFi, Hypex, Bryston, Marantz, and a 1979 Aiwa micro integrated amp
View attachment 508366
I put the mic at the face of the D2 lens, measured ambient noise with an without the L-pad, and compared to the other noisier amps using the L-pad. The Aiwa was thrown in for fun, but actually has acceptable noise with the L-pad. Sorry that the graph is busy with poor colors. Basically the L-pad takes an amp that has barely audible noise like the Bryston and makes it inaudible unless I stuff my ear in the lens.
I think the capacitor for both 6dB/oct filter and DC blocking is a great implementation.
I guess the drawback is if you need a larger amp to account for the 9 dB loss in sensitivity. You also need to change the filter capacitor if you want to change the DSP crossover since they are integrated, but this is minor.
I also think it is a tremendous sounding speaker.
MAB gave you a better answer than I could - thanks MAB!
Very thorough response.A few things come to mind.
The L-pad smooths out the driver's impedance peak.
Here is the impedance of a D2 driver mounted in it's lens with no filter (blue), the L-pad only (red), and the complete network (green):
View attachment 508336
Some amps may become unstable with this high impedance.
The impedance resonances do change the frequency response which could be addressed in the DSP filters.
View attachment 508357
But the L-pad appears to be damping the resonances seen in the impedance curve, especially in the red trace where I drive the speaker with only the 8 uF filter capacitor and no L-pad. You can see in the red trace the impedance peaks are interacting with the filter capacitor and making additional response unevenness with higher peak at 600-700 Hz, lower trough at 800-900 Hz, and a larger ripple in the 1-2 kHz region. This translates to less filter EQ needed to get to the desired response. Those closely-spaced ripples are hard to EQ. The cost is 9 dB less voltage sensitivity, which in the case of this driver is actually an advantage for me since it plays absolutely terrifying SPL with just a few Watts.
The impedance resonance anomalies are often best removed at the source in my simple experience, although am not an expert on resonances in non-linear systems. I do see a spike in 2nd HD at 600-700 Hz with the 8 uF capacitor, but it really isn't dramatic. I would be interesting if Dr. Toole or maybe @Frank Dernie have comments or considerations about damping these resonances with the L-pad.
View attachment 508369
This is no big deal on distortion, even if we can see a spike. Perhaps at higher SPL this becomes more dramatic due to nonlinear behavior of these resonances, JBL likely have data but out of self-reservation I won't test that loud!
Thatt 9 dB reduction in sensitivty can be an advatage, the network reduces audible noise allowing the driver to be powered by a range of amplifiers even with elevated noise specs. I actually compared the noise of the driver with and without the passive crossover across a range of amplifiers; PuriFi, Hypex, Bryston, Marantz, and a 1979 Aiwa micro integrated amp
View attachment 508366
I put the mic at the face of the D2 lens, measured ambient noise with an without the L-pad, and compared to the other noisier amps using the L-pad. The Aiwa was thrown in for fun, but actually has acceptable noise with the L-pad. Sorry that the graph is busy with poor colors. Basically the L-pad takes an amp that has barely audible noise like the Bryston and makes it inaudible unless I stuff my ear in the lens.
I think the capacitor for both 6dB/oct filter and DC blocking is a great implementation.
I guess the drawback is if you need a larger amp to account for the 9 dB loss in sensitivity. You also need to change the filter capacitor if you want to change the DSP crossover since they are integrated, but this is minor.
I also think it is a tremendous sounding speaker.
Voltage generated across the voice coil ("back EMF") is approximately proportional to coil velocity, so if mechanical nonlinearities dominate (as they tend to around the fundamental diaphragm resonance), maximizing this velocity feedback via low (or even negative) source impedance will help linearize the system.
In the RL circuit? Yes, but less than in the other one. Assuming an ideal inductance, the shunt impedance goes to zero at DC. Since the source impedance seen by the driver is the parallel combination of R and L, the source impedance is then zero at DC. In practice, of course, inductors have some parasitic resistance, but it will still be much lower than the shunt R in an L-pad.
