Really intrigued by the SBA satori drivers, so I decided to give them a try and start a build with them.
Instead of starting from scratch I want to go with a proven design. Troels’ SBA MW19 looks really interesting to me.
However I was wondering, if I would ever feel the need would it be possible to add a woofer and make it a three way construction like Jeff Bagby did with the Kairos three way? (Possibly sealing the port on the MW19 monitor).
Assuming it is possible: at this point I am thinking about either SB34NRX75 or SB29NRX75.
Correct me if I’m wrong, but sensitivity wise this shouldn’t be much of a problem I think (90dB for SB34, 88dB for SB29 and 88dB for the monitor).
For the Kairos three way Jeff Bagby uses a passive crossover between the woofer and the monitor (in his case a LR2 at 200Hz).
Would this be advisable or would it compromise the monitor’s performance? Would an electronic crossover be better?
Instead of starting from scratch I want to go with a proven design. Troels’ SBA MW19 looks really interesting to me.
However I was wondering, if I would ever feel the need would it be possible to add a woofer and make it a three way construction like Jeff Bagby did with the Kairos three way? (Possibly sealing the port on the MW19 monitor).
Assuming it is possible: at this point I am thinking about either SB34NRX75 or SB29NRX75.
Correct me if I’m wrong, but sensitivity wise this shouldn’t be much of a problem I think (90dB for SB34, 88dB for SB29 and 88dB for the monitor).
For the Kairos three way Jeff Bagby uses a passive crossover between the woofer and the monitor (in his case a LR2 at 200Hz).
Would this be advisable or would it compromise the monitor’s performance? Would an electronic crossover be better?
If in doubt and without a chance to test, I advise to build the proven 3 way kit right from the start.
You can't make a two way into a three way without re-designing the crossover.
You could add a subwoofer, preferably active, without too much difficulty. A sealed box with a 7" driver does lend itself well to sub integration without any modification.
You could add a subwoofer, preferably active, without too much difficulty. A sealed box with a 7" driver does lend itself well to sub integration without any modification.
That would probably be better. Maybe I should take a look at the kairos three way.
Maybe I'm not using the right terms. I got my idea from Jeff Bagby's three way kairos.
He used what he calls a (sorta) universal crossover. In the paper Jeff says the following:
Link: https://app.box.com/s/a4bqr447s7ox7v9kt7r9tjui0h7yqkrv
Troels did something similar with an electronic crossover (although that was more of a pre-study): 10C77
I like your idea about adding an active subwoofer, I think that should work pretty well for my needs. I'll look into that, thanks!
with respect to not being able to turn a two way into a three way without redesigning the crossover, I'd say yes and no. If the two way has a passive crossover and you go active for the woofer to two way then you can do it.
That is what I did with my MTM's I always intended to use my 10" woofers down the track, I got the mtm's how I wanted them and then I designed the active crossover to work with the woofers and MTM's as they were. It worked very well without needing any redesign of the MTM's passive crossover.
If on the other hand you were trying to change a passive two way design to a passive three way design then yes, I would think a crossover redesign would be necessary.
Tony.
That is what I did with my MTM's I always intended to use my 10" woofers down the track, I got the mtm's how I wanted them and then I designed the active crossover to work with the woofers and MTM's as they were. It worked very well without needing any redesign of the MTM's passive crossover.
If on the other hand you were trying to change a passive two way design to a passive three way design then yes, I would think a crossover redesign would be necessary.
Tony.
A link that you provided is a nice way of explaining how things work. 2 way satori you're interested in is a really bass capable loudspeaker in a 30 litres enclosure and I would be perfectly satisfied with it but that's an unknown with other people. If you are interested in solving technical issues and you believe that you will eventually make it work, then it's probably safe enough to build the 2 way.
Some woofer amps include active LR4/LR4 crossovers, and even a 3-5 band frequency equalizer to smooth some room effects.
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For a single 3-way TMW speaker cabinet, you will get the best sound if you build the Satori MW19P into a well engineered 0.5cuft sealed volume with Qtc = 0.6-0.7 for optimum transient reproduction down to -F3 = 72Hz, and bi-amp to a sealed volume 12" woofer.
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You will get the most flexible usage model if you build the Satori MW19P into a 0.8-0.9cuft ported separate TM cabinet volume to -F3=38Hz like Troels SBA MW19 monitor or Illuminator monitor, and construct a separate woofer cabinet. You get multiple uses (desktop, dorm, bedroom, kitchen) with just the modest size/weight ported TM monitor. You can plug the port for improved midbass transients, and bi-amp (LR4/LR4 @80-100Hz) with a sealed woofer.
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A musical woofer(Mms=99g) like the 12" SB34NRX75-6 in a sealed 4.4cuft volume reaches -F3 = 35Hz. A more expensive Plate-Amp which provides bass equalization can produce deeper bass in a smaller box volume plus modest room equalization.
A 12" subwoofer(Mms=192g) like the Dayton RSS315HFA-8 trades lower efficiency of 85db to produce -F3 = 35Hz in a 3cuft box without equalization, and deep loud bass with a large amp with boost.
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How good are your wood working skills/shop?
1) construct simple boxes
2) construct complex low diffraction baffle boxes
3) purchase pre-built cabinets from Parts Express
Also consider SB's new range of white 'deep ceramic' drivers..utterly gorgeous. A 3 way shouldnt be too hard to model, all drivers seem well behaved. The 8" 4 ohm has 90db sensitivity / f3 of 30hz in 45 litres.
It looks really nice, but the construction looks a bit hard to be honest.
Thank you for the thorough response. I really like the idea about the flexibility, so I'm leaning towards building Troels' SBA WM19 monitor as is and adding a woofer later. Preferably the SB34NRX75-6 with a good plate amp.
About the wood working skills I would say I can construct simple boxes. The cabinets of the SBA WM19 monitor shouldn't be a problem.
Do you mean the PNW versions of the drivers, or am I missing something?
These.. altho those white satori's are gorgeous too, so stick with your plan imo
SB Acoustics :: COMING SOON
SB Acoustics :: COMING SOON
32y0
If you decide to purchase pre-built TM cabinets like the Parts Express designs with a flat baffle:
--you can consider a fast T-M transfer like a LR4/LR4 crossover to reduce the noticable time delay effects.
---Woofer Plate amp is often LR4/LR4, and with LR4/LR4/LR4 on the W-M-T all drivers are in phase.
--you can consider a L-C Ladder time delay element on the tweeter instead of the 2-level stepped baffle in the Troels WM19
--------Troels uses an L-C delay in the Illumininator Monitor.
If you decide to purchase pre-built TM cabinets like the Parts Express designs with a flat baffle:
--you can consider a fast T-M transfer like a LR4/LR4 crossover to reduce the noticable time delay effects.
---Woofer Plate amp is often LR4/LR4, and with LR4/LR4/LR4 on the W-M-T all drivers are in phase.
--you can consider a L-C Ladder time delay element on the tweeter instead of the 2-level stepped baffle in the Troels WM19
--------Troels uses an L-C delay in the Illumininator Monitor.
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