After grappling with trying to put my subjective impression into words, maybe a few thoughts on Amir's objective measurements.
The near field resonances from the sub look slightly alarming. It is hard to tell how relevant they are going to be further away, or since they are beaming up, at the listening position. I wonder why they are so strong. Maybe this is feedback pushing nonlinearites to higher orders? Cutting the bandwidth of the output will also diminish the phase reserve available for LF feedback. Tough call on how to optimize. Maybe an acoustic absorber integrated into the grille? But in order to filter those resonances, the grill would have to become deeper.
Distortion-wise, very nice performance. As mentioned before, there is no evidence of harmonics exciting the cone modes of the W22EX midbass. The tweeter is straining around 2 kHz at higher SPL. Did this newer version of the DXT get a new motor with better saturation and/or some demodulation?
I wouldn't make too much of the 700 Hz distortion peak that appears only in the 100 dB/1 m measurement. It is defintely not excitation of the cone mode because the frequency is wrong and it excites all harmonics equally. I would guess it is something that rattles in the room, the test rig or (unlikely) the speaker cabinet. It appears well damped at low and intermediate SPL but at some point, whatever damping there is comes to a limit or it starts hitting something that resonates.
Lastly, I did an overlay with Amir's measurements of the KEF R11 Meta. I have chose that speaker because I have the R3 Meta which shares the same Uni-Q driver and also, because Amir's Klippel measurements appear highly consistent among themselves (other than some very early reviews). I also suspect Amir's microphone has lower distortion than Erin's and maybe Nuyez'. This is the reason why I didn't choose a Reference Meta review which would be closer in price to the LS1c but hasn't been measured by Amir.
This is the LS1c at 96 dB/1 m and the R11M overlaid with transparancy. The R11M is clearly about 20 dB better from 1.5 to 3 kHz. This might be the DXT straining. Most of this is HD2, so probably not critical. But HD3 is also about 5 dB and HD5 about 10 dB higher. In the range of 0.5 to 1.5 kHz, there is maybe a slight advantage for the R11M but they are really close.
The range below 200 Hz is interesting. The LS1c is easily 10 - 15 dB higher throughout, and this is not just HD2 but also HD3 and HD5 where the R11 M is consitently lower. The R11M sports four 6.5 in woofers AFIK without demodulation and has no sub. The Reference series woofers are better (compare Amir's review of the Reference 4c or Erin's level dependent measurements of the R3 and Reference 1). The LS1c has a single 8 in driver, but it sits on a wide baffle, it has two massive copper rings, and it is supported by a woofer. So what is going on here? We know back from Zaph's and HobbyHifi measurements that the W22EX is not as good far down as e.g. the 22W8555, but because it is crossed over to the sub, this should not matter here. So is it those resonances from the sub popping up here?
We get a similar picture at 102 dB for the R11M and 100 dB for the LS1c. The KEF is lower at LF and HF. It is now a tad worse in the 500 - 1 kHz range, but then it is also outputting 2 dB more. As to how relevant this all is, probably not so much.
On a side note, I'd be interested in hearing what the rationale is behind the tweeter upgrades. What do those beryllium and now carbon ply domes to either objectively that would show up in the NFS measurements or subjectively? Were there also motor upgrades?
The near field resonances from the sub look slightly alarming. It is hard to tell how relevant they are going to be further away, or since they are beaming up, at the listening position. I wonder why they are so strong. Maybe this is feedback pushing nonlinearites to higher orders? Cutting the bandwidth of the output will also diminish the phase reserve available for LF feedback. Tough call on how to optimize. Maybe an acoustic absorber integrated into the grille? But in order to filter those resonances, the grill would have to become deeper.
Distortion-wise, very nice performance. As mentioned before, there is no evidence of harmonics exciting the cone modes of the W22EX midbass. The tweeter is straining around 2 kHz at higher SPL. Did this newer version of the DXT get a new motor with better saturation and/or some demodulation?
I wouldn't make too much of the 700 Hz distortion peak that appears only in the 100 dB/1 m measurement. It is defintely not excitation of the cone mode because the frequency is wrong and it excites all harmonics equally. I would guess it is something that rattles in the room, the test rig or (unlikely) the speaker cabinet. It appears well damped at low and intermediate SPL but at some point, whatever damping there is comes to a limit or it starts hitting something that resonates.
Lastly, I did an overlay with Amir's measurements of the KEF R11 Meta. I have chose that speaker because I have the R3 Meta which shares the same Uni-Q driver and also, because Amir's Klippel measurements appear highly consistent among themselves (other than some very early reviews). I also suspect Amir's microphone has lower distortion than Erin's and maybe Nuyez'. This is the reason why I didn't choose a Reference Meta review which would be closer in price to the LS1c but hasn't been measured by Amir.
This is the LS1c at 96 dB/1 m and the R11M overlaid with transparancy. The R11M is clearly about 20 dB better from 1.5 to 3 kHz. This might be the DXT straining. Most of this is HD2, so probably not critical. But HD3 is also about 5 dB and HD5 about 10 dB higher. In the range of 0.5 to 1.5 kHz, there is maybe a slight advantage for the R11M but they are really close.
The range below 200 Hz is interesting. The LS1c is easily 10 - 15 dB higher throughout, and this is not just HD2 but also HD3 and HD5 where the R11 M is consitently lower. The R11M sports four 6.5 in woofers AFIK without demodulation and has no sub. The Reference series woofers are better (compare Amir's review of the Reference 4c or Erin's level dependent measurements of the R3 and Reference 1). The LS1c has a single 8 in driver, but it sits on a wide baffle, it has two massive copper rings, and it is supported by a woofer. So what is going on here? We know back from Zaph's and HobbyHifi measurements that the W22EX is not as good far down as e.g. the 22W8555, but because it is crossed over to the sub, this should not matter here. So is it those resonances from the sub popping up here?
We get a similar picture at 102 dB for the R11M and 100 dB for the LS1c. The KEF is lower at LF and HF. It is now a tad worse in the 500 - 1 kHz range, but then it is also outputting 2 dB more. As to how relevant this all is, probably not so much.
On a side note, I'd be interested in hearing what the rationale is behind the tweeter upgrades. What do those beryllium and now carbon ply domes to either objectively that would show up in the NFS measurements or subjectively? Were there also motor upgrades?
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