Thank You! You just confirmed my analysis:
Also, you just confirmed the OP is wrong!
Could you, please, make the same type of graph for vented loudspeaker (with HornResp)?
I am confident it will confirm my analysis for vented box efficiency:
He didn´t. He pulled true efficiency based on apparent power graph from the hornresp, not "SPLe based on real power".
No it wont. As the graph from Hornresp is Efficiency, not a SPLe.
This was purely anecdotal, not causal, and the approach is like stuffing your ears, doing "lalala"...
Still, 18IPAL is more efficient at, and below tuning, even with apparent power:
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I just did something similar. Same size enclosure as before, vented with Fb=25Hz. Again the Seas is grey and the IPAL is Black. Ignore the port resonance at 200Hz.
I checked my Seas A26RE4 input data and it matches the datasheet, Re=6.3 BL=9.7, Fs=25, Vas=169, Qm=3.84, Qe=0.43
There is no question in my mind that the IPAL has higher output per watt than the Seas driver in a 100L ported box throughout the bass range. This ignores the loss in efficiency caused by voicecoil heating that will effect the Seas driver far worse than the IPAL.
I checked my Seas A26RE4 input data and it matches the datasheet, Re=6.3 BL=9.7, Fs=25, Vas=169, Qm=3.84, Qe=0.43
There is no question in my mind that the IPAL has higher output per watt than the Seas driver in a 100L ported box throughout the bass range. This ignores the loss in efficiency caused by voicecoil heating that will effect the Seas driver far worse than the IPAL.
Great!
Only if it could show further difference with real power.
Now, keep in mind the IPAL has much stiffer suspension, diminishing true efficiency of the motor some more than Seas. The High Bl motor alone runs much further. Therefore Low Qes speakers took place in the manufacturers portfolio to push the SPL further.
Only if it could show further difference with real power.
Now, keep in mind the IPAL has much stiffer suspension, diminishing true efficiency of the motor some more than Seas. The High Bl motor alone runs much further. Therefore Low Qes speakers took place in the manufacturers portfolio to push the SPL further.
IPAL requires the stiff suspension and heavy cone to survive abuse in the prosound environment. Even more could be achieved if this ruggedness was not required.
Interesting to note my sim showed higher efficiency than yours, on both drivers. Was your enclosure 100L?
Interesting to note my sim showed higher efficiency than yours, on both drivers. Was your enclosure 100L?
Yes, once the 1000N peak can show at the cone, stuff must be very rugged, otherwise something is going to give. I just pointed to the fact that if all else was equal, and we compared just motors, we would see even more difference in efficiency, as you noted too.
Yes, my enclosure was 100l. We would need to compare full screens of input data I guess.
Yes, my enclosure was 100l. We would need to compare full screens of input data I guess.
Our numbers are quite different especially for the IPAL. The spec sheet gives BL=24.5 for the IPAL and 9.7 for the A26RE4. Those numbers came off the current datasheets for those two drivers.
I just spotted your second driver is the 18DS115, not the IPAL.
I just spotted your second driver is the 18DS115, not the IPAL.
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Thank You again! You confirmed my analysis that Efficiency graphs for vented speakers must have valley around the tuning frequency (here around 25Hz), plus two peaks (here at around 17Hz and at 45Hz/60Hz) - all corresponding to the impedance vs frequency graph of used woofers in a vented enclosure.
Bolded: You compared 10" hi-fi Seas woofer with 89dB/2.83V/1m sensitivity (89dB/1W at 8 ohms) to 18" pro IPAL woofer with 97/1.4V/1m sensitivity (97dB/1W at 2 ohms). That is totally unfair - that is the extreme example of apples to oranges comparison. Please compare the same 18IPAL woofer to any other 18" pro woofer (non - IPAL), for example Eighteen Sound 18NLW9400, or RCF LF18N451, or B&C 18DS100, or B&C 18DS115. You will be surprised how similar they will be to 18IPAL.
@cowanaudio:
You are right. My mistake. Still after speaker correction, I got different numbers. Yours reach nearly 2% efficiency at ~16Hz. Maybe different version of hornresp has different equations and corrections.
Also phase angle in the Hornresp is so hard to read. //Could we install the same version, and would you post your input table? Thank you.
You are right. My mistake. Still after speaker correction, I got different numbers. Yours reach nearly 2% efficiency at ~16Hz. Maybe different version of hornresp has different equations and corrections.
Also phase angle in the Hornresp is so hard to read. //Could we install the same version, and would you post your input table? Thank you.
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That is not what he confirmed you, as you wrote exactly this:
You asked for different confirmation. And so called "SPLe" indeed is not efficiency, which you claimed too. I think I never denied that the efficiency would have this shape. I denied that SPL under 1W of input power would copy that shape. And indeed it does not copy that shape. I was only one to show that to this moment though.
yes, because they have strong motor. with either high Bl (mostly) or weaker suspension. :-D That´s the reason behind it.
It was fair when Seas shown you bigger numbers in the voltage driven simulator, wasn't it? Before it was wrong, now it is just unfair. Of course it is. We are not discussing fairness though.
I went as far as asking the creator of Hornresp to add this function for us, so we do not have to count like crazy. Let´s see where it goes. I would be burning through time and money doing it manually, so it makes sense to even pay for the David´s job to have it implemented, as it is big and misunderstood problematics.
There are only two very small differences in your HR input screen compared to mine. My Lp is 75, giving slightly higher tuning frequency (Ap is the same). My BL is 24.5 per the current spec sheet. I direct entered BL off the spec sheet rather than let HR calculate it. Everything else is identical. I'm on HR 50.70
My version is 53.20 and After the last correction you provided, I still get different outcome. :-(
Under 6% efficiency in band, under 1% the bottom peak.
Under 6% efficiency in band, under 1% the bottom peak.
I just installed 53.20 and now I only get 5.8% at 70Hz and 0.8% at 16Hz. I liked the old version better 😠
I don't update HR too often because I'm on Linux and It's a bit more of a chore to update than on a Windoze machine.
I don't update HR too often because I'm on Linux and It's a bit more of a chore to update than on a Windoze machine.
Glad it is the Hornresp Version. Are we going to continue like that, to extrapolate the "SPL efficiency" with CosFi implemented? I am still weirded out by the Hornresp impedance phase graph. It turns around all four quadrants. 😯
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Don't I know it. I run Arch BTW 🙂 .
So to sum all of this up, a higher motor strength will have higher output and lower real power consumption than a lower motor strength driver with all else being equal? I'm not sure why that's controversial.
Maybe a stupid question, but when we are talking about efficiency, are we talking watts or VA?
Low watts can still have high VA, and therefore high current due to the phase, and voice coil heating is I squared x R, not watts
On my speaker that I posted the impedance of earlier, the impedance phase goes from +45 to -45 degrees just above port tuning, so VA would be almost 2 x watts at those points
Brian
Low watts can still have high VA, and therefore high current due to the phase, and voice coil heating is I squared x R, not watts
On my speaker that I posted the impedance of earlier, the impedance phase goes from +45 to -45 degrees just above port tuning, so VA would be almost 2 x watts at those points
Brian
Real power = U x I x CosFi [Watts].
We are talking about real power. That is with some leeway considered as heating power. That is the same thing as Isquared R x cosFi. Same Watts of real power.
45 degrees results in 0.7x or /0.7 power, not double/half. Double/half is 60 degrees. And indeed that is what happens. Those high Bl beasts turn phase around 60 degrees over wider band. 💪
We are talking about real power. That is with some leeway considered as heating power. That is the same thing as Isquared R x cosFi. Same Watts of real power.
45 degrees results in 0.7x or /0.7 power, not double/half. Double/half is 60 degrees. And indeed that is what happens. Those high Bl beasts turn phase around 60 degrees over wider band. 💪
Reporting back about my Seas 10" adventures:
Goal is to find a woofer with any efficiency that can do 20-200Hz and have a nice scooped response, because I like the way it sounds at low listening levels.
Measurements were done with the two different Seas drivers in right and left cabinet.
The other channel was muted during measurment.
Measurement distance was 50 cm away with the infamously bad Minidsp Umik-1 microphone.
Measurements tell me I have a lot of work to do with room treatment to get rid of room modes. I included an old measurement of an Eminence Lab12 12" subwoofer, which measures equally as terrible and with the same exact room modes below 100Hz!
After ten minutes listening I could not hear the difference between the Seas A26RE4 (blue line) and Seas W26FX002 (black line). It was only when I put my ear against them could I hear what was going on. Seas A25RE4 has slightly extended midrange, so works okay in a two way.
But I am planning for more exciting lower midrange (a modded Lowther PM2A) and I need a woofer that can do 20-200Hz. Enter Seas W26FX002 - this driver is more damped and has better control of the bass, even if my room modes are completely uncontrollable. It also has a nice rolloff above 200Hz, which is exactly what I want from it. One less crossover component to worry about. The bass is really deep and I need some heavy room treatment to fix it. Or just use Room EQ.
Since we are supposed to compare high efficiency drivers VS low efficiency drivers, here is the JBL K140 (Red line) in the same enclosure, but with ports on the front. Oh, and look - there is no 550Hz dip. Could it be the front facing ports I used to have? It just never went low enough to be used without a subwoofer. When playing at low listening levels, which I often do, I prefer a scooped graph, not the opposite. Same was the case for the 15PR400 in the same cabinet. To get more bass out of these large 15" PA woofers, I could have built a gigantic 170L cabinet, but 75L was already quite large. But they would never be scooped like these two Seas drivers.
Goal is to find a woofer with any efficiency that can do 20-200Hz and have a nice scooped response, because I like the way it sounds at low listening levels.
Measurements were done with the two different Seas drivers in right and left cabinet.
The other channel was muted during measurment.
Measurement distance was 50 cm away with the infamously bad Minidsp Umik-1 microphone.
Measurements tell me I have a lot of work to do with room treatment to get rid of room modes. I included an old measurement of an Eminence Lab12 12" subwoofer, which measures equally as terrible and with the same exact room modes below 100Hz!
After ten minutes listening I could not hear the difference between the Seas A26RE4 (blue line) and Seas W26FX002 (black line). It was only when I put my ear against them could I hear what was going on. Seas A25RE4 has slightly extended midrange, so works okay in a two way.
But I am planning for more exciting lower midrange (a modded Lowther PM2A) and I need a woofer that can do 20-200Hz. Enter Seas W26FX002 - this driver is more damped and has better control of the bass, even if my room modes are completely uncontrollable. It also has a nice rolloff above 200Hz, which is exactly what I want from it. One less crossover component to worry about. The bass is really deep and I need some heavy room treatment to fix it. Or just use Room EQ.
Since we are supposed to compare high efficiency drivers VS low efficiency drivers, here is the JBL K140 (Red line) in the same enclosure, but with ports on the front. Oh, and look - there is no 550Hz dip. Could it be the front facing ports I used to have? It just never went low enough to be used without a subwoofer. When playing at low listening levels, which I often do, I prefer a scooped graph, not the opposite. Same was the case for the 15PR400 in the same cabinet. To get more bass out of these large 15" PA woofers, I could have built a gigantic 170L cabinet, but 75L was already quite large. But they would never be scooped like these two Seas drivers.
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