-
WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!
LS50 meta's plus sub vs More expensive speakers
- Thread starter Eternals
- Start date
Right, but towers will have more capable midranges to keep up with the bass drivers. The LS50's Uni-Q was no doubt engineered knowing where it would hit excursion limits.
I'm looking at KEF's spec sheets. They show a clear progression of sensitivity and volume as you work your way up:
- LS50 Meta: 85dB sensitivity, 106dB max
- R3: 87dB sensitivity, 110dB max
- R11: 90dB sensitivity, 113dB max
- Blade: 91dB sensitivity, 117dB max
PS I note the LS50 Wireless II does push up to 108dB full-range with its intelligent bass extension. That does suggest at least 108dB should be possible above an HPF in the LS50 Meta. If you too use a 200W amplifier like the Wireless II...
- Joined
- Jan 15, 2020
- Messages
- 6,904
- Likes
- 16,933
KEF states the R2c also with 87 dB (2,83 V / m), same as the R3, according to above plot its around 85-87 depending on the range and averaging.
it's 84.8 dB in reality, and like i said, the addition of an extra woofer on top of the R3 did not increase sensitivity, I doubt the towers show any significant difference in sensitivity.
KEF didn't claim the R2C had greater sensitivity than the R3. They spec it the same 87dB. The R2c and R3 aren't directly comparable - it's sealed versus ported.
It does look like KEF have a tendency to quote a number based on the high part of the frequency response - they show all the FR curves for the range in the R series white paper. And looking at them, yep, if the highest plateau is 90dB, they'll call it 90dB, even if the 100Hz-20kHz average clearly isn't.
But they do that consistently, and the sensitivity curves are progressively higher in each model.
It does look like KEF have a tendency to quote a number based on the high part of the frequency response - they show all the FR curves for the range in the R series white paper. And looking at them, yep, if the highest plateau is 90dB, they'll call it 90dB, even if the 100Hz-20kHz average clearly isn't.
But they do that consistently, and the sensitivity curves are progressively higher in each model.
- Joined
- Jan 15, 2020
- Messages
- 6,904
- Likes
- 16,933
The KEF measurements show clearly that the sensitivity increases:
R3
R5
R7
R11
Source: https://us.kef.com/pub/media/documents/rseries/rseries2018-white-paper.pdf
No, but you claimed that the addition of more bass drivers will raise the sensitivity, but from the data we have that is not necessarily the case. the R2C should theoritically have 3dB higher sensitivity than the R3.
Ofcourse we can compare them, the R2c's woofers roll-off more quickly.
More bass drivers gives you the potential for more sensitivity. In which case the other drivers will need to be made more sensitive to match.
But if you're changing other things, like cabinet volume and adding/removing ports, then there will be other factors.
But in the R2C's case they're actually smaller drivers! 2x130mm rather than 1x165mm. That's only 24% more bass driver area, so it wouldn't even be enough for 1dB anyway.
The dual drivers gives symmetry, and the slightly increased area presumably counteracts lack of port, but it's not enough to make it louder.
If you would pay a little extra attention, you would see the sensitivity dropping off in the mids and highs as you progressively add more bass drivers, with the R3 being the flattest accross the board. Also i just realized how solid the reference line-up is! really state of the art.
I find it hard to discern the trend - the waves seem different in each measurement. Bass is clearly going up monotonically, but the mid and upper vary.
If anything it looks like the tweeter is failing to keep up.
R11 and R3 have massively different midrange, but R5 and R7 look very similar. Looks like R7 could do with a midrange boost.
If anything it looks like the tweeter is failing to keep up.
R11 and R3 have massively different midrange, but R5 and R7 look very similar. Looks like R7 could do with a midrange boost.
- Joined
- Jan 15, 2020
- Messages
- 6,904
- Likes
- 16,933
The higher models are truly tuned warmer but even there for example the R11 is around 87-88 dB while the R3 is around 85dB. Obviously the first number is the limit of sensitivity of the used Uni-Q.
FWIW, here's the 3-way crossover from the R-series paper - you can see resistors R1 and R2 that lower the mid and tweeter levels in the Uni-Q, with the bass drivers determining overall sensitivity.
(Perhaps the R11 might not have R2 if it was well-designed enough that the midrange precisely matches the bass drivers in that 4x165mm config?)
In the LS50 Meta, the midbass determines sensitivity, with the tweeter being lowered by R1.
(Perhaps the R11 might not have R2 if it was well-designed enough that the midrange precisely matches the bass drivers in that 4x165mm config?)
In the LS50 Meta, the midbass determines sensitivity, with the tweeter being lowered by R1.
The design does appear different between the Rx's and LS50/M, but isn't that primarily in the flange/suspension and overall woofer diameter? I think the tweeter waveguide is identical in size and shape.
Colonel7
Addicted to Fun and Learning
12 db slope. Harrison labs makes various Hz passes both high and low
https://www.amazon.com/FMOD-Crossover-Pair-High-Pass/dp/B0006N41KG
Ultrasonic
Addicted to Fun and Learning
Apologies if I've missed that someone else has already mentioned this but the Hegel H120 has pre-amp outputs and so there is no need for a high-level connection here.
this is amazing! thanks for sharing! 12dB slope is a bit slow though, wish there were more slopes option.
Colonel7
Addicted to Fun and Learning
You're welcome. I thought they made 24db too but I can't find any. Most of the reviews that rate them low seem to misjudge the pass db per octave or mistakenly think it's a brick wall.
