Is there a better way to estimate the spl of the woofer at 4 Pior in room, than the conventional -6dB vis à vis of the 2 Pi datas ?
As many can't measure outside the bass in its cabinet, should we need to put the SLS12 in the 70 L load and measure inside with the modes ? So to be clearer put the mic at the main seat spot, whatever it is 3 meters, to have an estimation of the sensivity at 2.83V in the room, then measure the others drivers at the same spot, from there make the offset measurement for Vituix ? So designing not on axis but with the offset of the listening sweet spot ?
I mean for the ones wanting to design it in their room and not in a virtual anechoic room for an universal filter construction project.
As many can't measure outside the bass in its cabinet, should we need to put the SLS12 in the 70 L load and measure inside with the modes ? So to be clearer put the mic at the main seat spot, whatever it is 3 meters, to have an estimation of the sensivity at 2.83V in the room, then measure the others drivers at the same spot, from there make the offset measurement for Vituix ? So designing not on axis but with the offset of the listening sweet spot ?
I mean for the ones wanting to design it in their room and not in a virtual anechoic room for an universal filter construction project.
See here
and here for merging examples
It's a very long thread, I would start with the VCad manual and how to carry out the measurements
https://kimmosaunisto.net/Software/VituixCAD/VituixCAD_help_20.html
https://kimmosaunisto.net/Software/VituixCAD/VituixCAD_Measurement_REW.pdf
https://kimmosaunisto.net/Software/VituixCAD/VituixCAD_help_20.html
https://kimmosaunisto.net/Software/VituixCAD/VituixCAD_Measurement_REW.pdf
Huh? Why would you promise something like that? How are you going to deal with the impedance peak? What's wrong with a 20 mH inductor?
Price if you put it in séries with woofer ans need low resistivity.
If you need a 60eu inductor, maybe it's better to get a more expensive woofer that would better match what we need.
Notches do not require a low dcr coil cause you have a resistance connected in series, even if adding notches is an additional cost.
https://www.rumoh.eu/crossover-part.../22.0mh-iron-cored-discs-0.50mm-rdc-3-600-ohm
https://www.rumoh.eu/crossover-part.../22.0mh-iron-cored-discs-0.50mm-rdc-3-600-ohm
The limit is clearly the budget and the availability.
The wavecor is >100 usd/euros. NE149W-08 is clearly better on specs and <70euros/usd, but we are waiting distributors, april/may ?
if the marmite cockroach you are talking about is the SB 4", many says like @profiguy, the SLS woofers are not good candidates to climb too much (here 320 hz to meet the SB12.
That's why I advocated for a 5" or the given up of a 12" if a 4" is prefered.
I do think the Gema open kit from the SB Acoustics has too much things wrongs : First the expensive SB34RNXL is not able to climb as high as the crossover cut off of this design to meet the SB12. Then I believe the mismatch is Sd size with a huge gap like 12" + 4" is not the best idea of the day ! Linton 85 Anniversary : 8"+5" ; Harbeth 40 : 12"+8" .
Do we want the revival of the shape AND the defaults of the oldest designs at the same time ??
It should not be so hard to choose a 5" , Peereless HDS (or else 5") off shelves yet from the above lists .... or make a decision like : the requirements are too stricts and it's going to be a waste for the monney involved. Danger being to have more monney in the wood and filter than the drivers perhaps. I don't know. YMMV but some talked choices above are certainly good enough.
Imo the geographical difficulty should not stop the project. It can start with partialy shared BOM of drivers or not.
The wavecor is >100 usd/euros. NE149W-08 is clearly better on specs and <70euros/usd, but we are waiting distributors, april/may ?
if the marmite cockroach you are talking about is the SB 4", many says like @profiguy, the SLS woofers are not good candidates to climb too much (here 320 hz to meet the SB12.
That's why I advocated for a 5" or the given up of a 12" if a 4" is prefered.
I do think the Gema open kit from the SB Acoustics has too much things wrongs : First the expensive SB34RNXL is not able to climb as high as the crossover cut off of this design to meet the SB12. Then I believe the mismatch is Sd size with a huge gap like 12" + 4" is not the best idea of the day ! Linton 85 Anniversary : 8"+5" ; Harbeth 40 : 12"+8" .
Do we want the revival of the shape AND the defaults of the oldest designs at the same time ??
It should not be so hard to choose a 5" , Peereless HDS (or else 5") off shelves yet from the above lists .... or make a decision like : the requirements are too stricts and it's going to be a waste for the monney involved. Danger being to have more monney in the wood and filter than the drivers perhaps. I don't know. YMMV but some talked choices above are certainly good enough.
Imo the geographical difficulty should not stop the project. It can start with partialy shared BOM of drivers or not.
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Way over budget and also no longer available.
Here is my sim of an over-the-budget, NLA driver... 😂 😂😁
This is not the "real" baffle, but I'm hoping it provides useful information. Consider whether mocking up a similar XPS foam board would be worthwhile for the SB12MNRX - it won't be exact, but it will at least be comparable to the 4" and 5" drivers that I measure.
I just choose a middle ground between the height and width of the JBL L100 and something about an inch bigger in both directions. My test baffle is 26-1/2 inch high and 15-3/4 inch wide. No edge treatments at all, just a rectangular baffle with sharp edges. I put the midrange centered vertically and center down 9" from the top. I also built a cardboard box 15 inches deep to more accurately reflect the off-axis measures with cabinet sides to reflect off of.
The key to even midrange FR on a large format 3 way speaker is the specific baffle circumference and length / width ratio. That's mainly due to the smaller diameter midrange (needing) being more reliant on the baffle step carrying alot of the lower mids further down. Without the baffle surface area, the midrange wouldn't have enough sensitivity to cross from a larger diameter LF driver. As some have already figured out, taking lead from existing designs, these baffle dim ratios have already been determined a while back by the big boys in the speaker building business. This is something that should be simmed, being so much easier to hone in on with Vcad, etc.
@shadowplay62 This is really nice, desirable power response and directivity trend off axis. The little mid dip is in the right place and actually a good thing.
In my own recent, still learning from experience, trials... a 500Hz bump in response, which guessing often from baffle/diffraction effect, gives annoying slappy upper bass sound. Take it away and sounds golden, cleaner. Regardless, this thread has been been very informative with nuggets of wisdom.
The off axis average in that above graph is great for a speaker that can play loud. The peaks and dips are in the right places... at least as long as HD doesn't also peak in those areas.
??
I think it was clear that we can forget it. Nobody are stocking them in Europe.
