SB Acoustics 3-way Build Idea

You're correct, merlinx76, and I apologize. I read the Maximum Excursion (11 mm) instead of Xmax (6.5 mm). Still your statement that a single 18W/8747 is nearly as capable as a pair of 18W/8531s is more than just a bit of an overstatement.
Paul
 
If you model the 2 systems in a sealed box with the same QTC, the 18W has an Fsc nearly 10hz lower which means it reaches Xmax quite a bit sooner. If I model them to Xmax, I get exactly the same db output from a single 18wu vs 2x18w except of course 10hz less low end extension.
 
Actually if you realise what is happening in a real vented woofer system, you might realise this, if properly done, the excursion peaks at a higher bass frequency. The work of low bass frequency is actually done by the port. Those woofers that actually see goes nuts are those that that has bass far below the port tuning frequency. That is when the woofer goes berserk, worst still it has no output. Example rumble from record player. If you can filter out the bass 5-10 Hz below your port tuning frequency, I doubt you will run out of steam...

Oon
 
I don't know how well that translates to real world. How does a little woofer sound playing 800hz while moving around by 9mm even if the motor is very linear? I assume there would be some downsides to the loss in cone area.
Are you aware of the SPL reached when a 7" woofer does 9mm one way at 800Hz? 😀

On low-cut BR systems: Applying a highpass on a vented system is pretty normal in PA. And for us audio fans it also has it's use, either as low end extension or as safety measure for smaller systems playing on the edge. Can be done with dsp easily and just as easily with an active op amp circuit. No news though here. The latter goes back almost 4 decades. FWIM search for D.B. Keele.
 
The cone material will have a large sonic effect. In the SB_line of drivers, there are a few posts which compare both the sonics and the measurements of cones constructed with: polyplastic like the MFC you are considering, paper, aluminum, and ceramic coated aluminum. In one word adjectives:
MFC plastic = smooth
Multi-fiber paper = natural
Ribbed aluminum = detailed
Ceramic coated Aluminum = detailed+

A pair of 8" SB23NBACS45-8 woofers can produce -F3 ~32Hz and save building plus itegrating a subwoofer. SB's ribbed aluminum cones have raised the first main cone breakup to ~4kHz. Can you fit a 3.5cuft cabinet to build stereo 3-way TM-WW, 1-6-(8-8)
Hallo Line Sourece

As I can see, you are very familiar with SB drivers. I am loking to build some 3 way floorstanders (TW29R+MW16P+ 8",10", 12") Do you have some developed projects/ sugestions?

Bestg Regards
 
I just finished a 3-way built around a set of SB Acoustics drivers. I am super pleased with the result. It is a sealed design and I extend the bass down to 30 Hz with a DSP. I find no need for any sub-woofers, especially since the bass quality from the SB23NRXS45-8 is great extended this way.

The build is fully documented on my blog:

Hi EmuMannen, I intereseted this Project Speakers, which final Crossover on 3 picture scheme XO ?
 
I ended up using a fully passive XO (the active and semi-active versions is slightly better but fully passive is more flexible for me amp rolling my vintage amps). I recommend extending bass down to 30 Hz with a LT or similar filter (even with a fully passive XO). Attached is the schema for the passive XO:

1692769993047.jpg
 
I just finished a 3-way built around a set of SB Acoustics drivers. I am super pleased with the result. It is a sealed design and I extend the bass down to 30 Hz with a DSP. I find no need for any sub-woofers, especially since the bass quality from the SB23NRXS45-8 is great extended this way.

The build is fully documented on my blog:

The 3-Way Retro no port, it means "sealed enclosure"...?

 
I just finished a 3-way built around a set of SB Acoustics drivers. I am super pleased with the result. It is a sealed design and I extend the bass down to 30 Hz with a DSP. I find no need for any sub-woofers, especially since the bass quality from the SB23NRXS45-8 is great extended this way.

The build is fully documented on my blog:

in : The 3-Way Retro Part 5 link, I found of DSP tools, what for that? actually its pasive speakers or active speakers? Have you picture rear side of speakers?
 
I have built them as active, semi-active and passive (it is all described in different blog posts). I ended up with the fully passive version but you can build them semi-active or fully active if you want. They look the same from the back in any configuration since the active versions was driven from external amps (including any active XO).
 
I ended up using a fully passive XO (the active and semi-active versions is slightly better but fully passive is more flexible for me amp rolling my vintage amps). I recommend extending bass down to 30 Hz with a LT or similar filter (even with a fully passive XO). Attached is the schema for the passive XO:

View attachment 1205539

I ended up using a fully passive XO (the active and semi-active versions is slightly better but fully passive is more flexible for me amp rolling my vintage amps). I recommend extending bass down to 30 Hz with a LT or similar filter (even with a fully passive XO). Attached is the schema for the passive XO:

View attachment 1205539
If I want to build
I ended up using a fully passive XO (the active and semi-active versions is slightly better but fully passive is more flexible for me amp rolling my vintage amps). I recommend extending bass down to 30 Hz with a LT or similar filter (even with a fully passive XO). Attached is the schema for the

Ikon Diverifikasi Komunitas

I ended up using a fully passive XO (the active and semi-active versions is slightly better but fully passive is more flexible for me amp rolling my vintage amps). I recommend extending bass down to 30 Hz with a LT or similar filter (even with a fully passive XO). Attached is the schema for the passive XO:

View attachment 1205539
If I want to built a full passive version of the speaker, is this xo scheme suitable/ideal?
Can the new version of the sb acoustic speaker with the norex code be used on the xo, or does the design have to be adjusted again

Ikon Diverifikasi Komunitas
 
I am not sure it does and “a more classic” is a matter of definition. I started out with the active and semi-active version of the speaker. The first XO board had to take care of the mid and high element. I therefor splitter the incoming signal at the lowest XO point with an active filter. I then added a separate board for the low element, just replaced the active filter with a passive block, when I made the fully passive version. I kept these branches and XO blocks separate to be able to switch between semi-active and fully passive and I wanted to modify the already made boards as little as possible. I hope it explains why the schematics ended up the way they did.
 
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