Can the 15″ SB42FHCL75-6 / Honeycomb play up to ~500 Hz, crossed over to a suitable midrange unit in a 3 way layout?
The FR seems good enough (maybe the 1.5 KHz peak will have to be notched out...?)... It is called a "sub"woofer by the manufacturer, which leads me to think that it is meant to play below ~100 Hz only...
The FR seems good enough (maybe the 1.5 KHz peak will have to be notched out...?)... It is called a "sub"woofer by the manufacturer, which leads me to think that it is meant to play below ~100 Hz only...
A desirable trait of a subwoofer driver that will be used at midrange frequencies, is good inductance control (shorting rings).
SB Acoustics remains silent about this aspect in the data sheet, which suggests that it does not have any. Also, check out this test:
Test Bench: The SB42FHCL75-6 15” Subwoofer from SB Acoustics | audioXpress
SB Acoustics remains silent about this aspect in the data sheet, which suggests that it does not have any. Also, check out this test:
Test Bench: The SB42FHCL75-6 15” Subwoofer from SB Acoustics | audioXpress
Test Bench: The SB42FHCL75-6 15” Subwoofer from SB Acoustics | audioXpress said:
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Are you talking about HT special effects sub, or a woofer for a three way? Personally, I much prefer about a 10 to a 5 to a tweeter. A good 10 can do 200 or 300 cleanly.
Just looking at a frequency sweep does not tell you anything about the polar response, transient response or distortion. I consider a 15 as either a PA ( very different driver) or a special effects sub. I would not even use a 15 for my music system.
But your system, your experience. Do whatever and learn. A lot of "sage" advice here is split from those of us who have built and failed and those who sit in chairs saying they did.
I am sure SB would make you 1000 or more pieces with a custom shorting ring.
Just looking at a frequency sweep does not tell you anything about the polar response, transient response or distortion. I consider a 15 as either a PA ( very different driver) or a special effects sub. I would not even use a 15 for my music system.
But your system, your experience. Do whatever and learn. A lot of "sage" advice here is split from those of us who have built and failed and those who sit in chairs saying they did.
I am sure SB would make you 1000 or more pieces with a custom shorting ring.
The midrange driver I am planning to use is the Volt VM752, which is not good below 500 Hz. It seems to be the only high output soft dome midrange driver available to DIY people.
The speaker design follows the tradition of the most revered British studio monitors like the ATC SCM150ASL Pro. The LF to midrange crossover here is @ 380 Hz, but they have a proprietary house built midrange driver.
The speaker design follows the tradition of the most revered British studio monitors like the ATC SCM150ASL Pro. The LF to midrange crossover here is @ 380 Hz, but they have a proprietary house built midrange driver.
What a load of rubbish. Too much moving mass to do what? We can see from the measurements provided above that it works absolutely fine up to 500Hz. Cross there with a 4th order acoustic slope and you're good to go. This is far more of a classic woofer than an actual sub and it's sensitive to boot.
I would also not do that, 300Hz with a higher order (at least 2nd order, preferable higher) would be ok, but i would use it as a real subwoofer (<150Hz). at 500Hz you will need a very steep lpf (4th order or even higher) to avoid the resonances higher up (starting at 600Hz). It's not only the peak at 2kHz that is bad, but also the smaller resonances lower that will hearable.
I see. Dome mid. You have no choice but to cross that high. I made few systems with mid dome and always crossed at 900Hz. But i built 4way.
You should be fine.
Go build and see. I would not cross a 15 to a 2, but I have been building speakers for 45 years and made enough mistakes to have an opinion.
Again, I suggest just an on-axis frequency response is a very limited description of the driver. There is this little problem of physics. Some have tried to build drivers where sections worked independently, think Ohm Walsh, but never successfully. Current best materials technology attempts to simulate a perfect piston.
Again, I suggest just an on-axis frequency response is a very limited description of the driver. There is this little problem of physics. Some have tried to build drivers where sections worked independently, think Ohm Walsh, but never successfully. Current best materials technology attempts to simulate a perfect piston.
Let’s assume for now that this will be an active speaker, so matching sensitivities among the drivers is not a requirement. If he is trying to emulate that ATC SCM150ASL Pro, he needs a good 15” driver, one that can reach up to 500 Hz to mate with the Volt 3” dome. ATC does it, and are able to charge $22000 (on sale!). JBL uses their 15” driver up to 700 Hz in the M2, so this is not an unreasonable demand to put on a 15” woofer.
So the question is can this particular SB woofer do the job? Based on the published specs, I would say yes. But the only way to really know is to build a speaker and see how it sounds.
So the question is can this particular SB woofer do the job? Based on the published specs, I would say yes. But the only way to really know is to build a speaker and see how it sounds.
I think it comes down to the age old argument of what level of non-linear distortion is audible. Comparing the SB34 and SB42 on hificompass site, the 'farfield' HD measurements show the SB34 to be 20dB lower than the SB42 in the ~100 to 400Hz region at 60dB abd 40dB below the fundamental (respectively). Whether 40dB below for the SB42 is still audible, I don't know