One of my favorite advantages of designing for DSP is how much simpler bass system design is, and how much better the end result is. Back in the day we needed to experiment with box volume, port specifications (length, crossection and flare, both ends) and, very tricky, internal baffling. The possible combinations were endless and the process of getting to the target took an adjustable mule and lots of hot glue and time on your knees. If you couldn't judge each iteration in a snap you were dead. And if you found yourself talking yourself into liking the end result, yup, dead.
Now we merely characterize each driver by observing what box volume results in best transient behavior - read: rise and settle times - then use that number each time we use that driver. We just manhandle the amplitude response in the processor to 'buy back' bottom end. So it' a clean process without relying on resonance to puff things up.
The idea is a breakthru for custom work because we can pretty much just cut-and-paste a build together from our stable of characterized drivers.
The volume layout of this four-driver three-way pretty much just falls into place with some consideration of economy of material. Barely a high school geometry project. There's plenty of room for a streamer bay at bottom.
You can see that we can pack a lot more transducer onto the baffle because the volume requirements are so much lower.
And, very nice, we can isolate the two woofers covering the same band. With a vented alignment, dividing the box volume in half like this results in about for times as much port, so the overall box dimensions so suffer badly that you just put up with the issues of two woofers sharing the same load.
Not a bad size. About what we had with Blue Heron, but much, much, much more speaker.
Testing for proof of concept was easy, if a bit silly looking. Two 9.5" Satoris in their proper volumes, one 7.5" Satori and, just for giggles, we toggled in and out a 'weak sister' bottom octave system that really couldn't keep up. So, no, we couldn't hit the target in the bottom half of the bottom octave - but we sure could convince ourselves that the 4x10" 1KW idea will hit a walk-off home run. Half that much is probably more than fine.
There's an FA252 hiding behind, driving the LF pumps.
With just the mains playing, a nifty range of bandwidth/amplitude trade-offs was apparent. And we're enjoying the kind of LF resolution we've come to expect. A little more because they're twins. And the midrange seems quite comfy rolling in at an arbitrary 120Hz with a five pole Butterworth. That's a fine point we'll worry about later. Anyway, we're both at 'thumbs up'.
Next, make some sawdust. Important not to get too attached to an idea - not to invest too much, not to make the proto's too pretty. We'll make a raw set that can we can launch into the dumpster without a second thought if they don't measure up. Just me, it's Murphy's Law upside down, make 'em pretty and, of course, they'll suck. I'm not superstitious, but you can doom your own project by getting too in love with it.
Now we merely characterize each driver by observing what box volume results in best transient behavior - read: rise and settle times - then use that number each time we use that driver. We just manhandle the amplitude response in the processor to 'buy back' bottom end. So it' a clean process without relying on resonance to puff things up.
The idea is a breakthru for custom work because we can pretty much just cut-and-paste a build together from our stable of characterized drivers.
The volume layout of this four-driver three-way pretty much just falls into place with some consideration of economy of material. Barely a high school geometry project. There's plenty of room for a streamer bay at bottom.
You can see that we can pack a lot more transducer onto the baffle because the volume requirements are so much lower.
And, very nice, we can isolate the two woofers covering the same band. With a vented alignment, dividing the box volume in half like this results in about for times as much port, so the overall box dimensions so suffer badly that you just put up with the issues of two woofers sharing the same load.
Not a bad size. About what we had with Blue Heron, but much, much, much more speaker.
Testing for proof of concept was easy, if a bit silly looking. Two 9.5" Satoris in their proper volumes, one 7.5" Satori and, just for giggles, we toggled in and out a 'weak sister' bottom octave system that really couldn't keep up. So, no, we couldn't hit the target in the bottom half of the bottom octave - but we sure could convince ourselves that the 4x10" 1KW idea will hit a walk-off home run. Half that much is probably more than fine.
There's an FA252 hiding behind, driving the LF pumps.
With just the mains playing, a nifty range of bandwidth/amplitude trade-offs was apparent. And we're enjoying the kind of LF resolution we've come to expect. A little more because they're twins. And the midrange seems quite comfy rolling in at an arbitrary 120Hz with a five pole Butterworth. That's a fine point we'll worry about later. Anyway, we're both at 'thumbs up'.
Next, make some sawdust. Important not to get too attached to an idea - not to invest too much, not to make the proto's too pretty. We'll make a raw set that can we can launch into the dumpster without a second thought if they don't measure up. Just me, it's Murphy's Law upside down, make 'em pretty and, of course, they'll suck. I'm not superstitious, but you can doom your own project by getting too in love with it.
