Bill Fitzmaurice

Of course. But one need not be an arborealist to know that maple and walnut will have higher density than poplar and spruce, while luthiers know which species give them what they, or their customers, want. Also of course. One disadvantage to high density wood is weight, so to keep the weight down you need to go with some measure of hollowing out the body. Mine I made of all rosewood, neck through, with the bouts made in two pieces, each hollowed out to about 6mm thick. This gives the high density advantages of bright tone, tremendous tuning stability and almost endless sustain without being too heavy. I like the looks of it too.

Wood species, and therefore density, makes a lot of difference in tone, as it directly impacts the resonant properties of an instrument. Speaker size alone doesn't. Interestingly I've noticed that a high percentage of those who think that wood density doesn't matter also think that the cone size does. 🤔

Myth. It would be true if voice coils reacted to electron waves within the realm of the speed of sound. They don't. They react within the realm of the speed of light. It's a good thing too, because the frequencies of the notes played are determined by how fast the cone moves. If larger cones moved more slowly you might play a C but it could be heard as a B. 😒

Compared to free-space, which is outdoors and elevated by at least a wavelength, on the ground is half-space, closer than 1/4 wavelength to a wall is quarter-space, closer than 1/4 wavelength to a corner is eighth-space. Each space reduction adds 6dB. This mainly applies to the lows, where speaker output is 360 degrees. 1/4 wavelength at 120 Hz is about 70cm, so ideally that's the furthest out you want the cab baffle from the wall. True. Where either the cab or you relative to each other or a boundary results in a 1/2 wavelength differential between the original source and a reflection there's a cancellation notch. Said boundaries include the floor and ceiling, so often the worst listening position is on the stage, where you can be getting multiple low frequency cancellations from walls, floor and ceiling. Further back in the room where the distance relationships are much longer the lows can be considerably louder than on the stage. This phenomenon was responsible for the myth of wave propagation, the notion that one must be a given distance from the source for a sound wave to fully develop and thus be fully heard. It's easily disproved by listening to the same speaker outdoors, where there are no boundaries that can cause cancellations.

Using more speakers outdoors is appropriate, as you're losing some 6dB or more of boundary reinforcement. That requires doubling the cab count to come out even, especially in the lows. The main issue with using dissimilar cabs is whether they'll integrate to help each other or whether they'll fight each other. You'll want to try it in a practice situation first.

When EQ'd for the same frequency response you cannot tell the driver size. You can have a dozen drivers of the same size with a dozen different frequency responses. When cabs have the same cone displacement, be it from one larger driver or more than one smaller drivers, they have the same maximum output. The only factor that's attributable to cone size alone is the dispersion angle, it grows narrower as the cone grows larger. Even that can be tweaked, and for that matter a pair of tens placed horizontal will have narrower dispersion than a single eighteen. In the end one factor, be it cone size or any of the more than a dozen factors that sum to give the end result, doesn't determine said result. It's that sum total.

While I'm at it, shelf style ports have two issues. The short height dimension can lead to chuffing, and they don't do double duty as braces unless located between the drivers. While this isn't a bass cab, it's a sub, I use the same design features in direct radiator bass and PA mains cabs: https://celestion.com/blog/build-this-21-inch-bass-reflex-enclosure-featuring-the-tsq2145/

Those dimensions give an approximate volume of 50L per driver with 55-60 Hz tuning, so the tuning is too high and the box is too big. A dividing shelf doesn't do anything other than to add bracing to the panels that it connects. You should have bracing, but as far as that's concerned a shelf is one of the least effective methods.

Unless the low pass inductor is seriously undersized, resulting in high DCR and potentially going into saturation, a low pass filter won't cause clipping of the low notes. That's usually the result of inadequate driver xMax/Vd, sometimes by the cab size and tuning. If you went with the WinISD default of 41 L per driver with 58Hz tuning you'd run out of excursion at only 80 watts per driver at 50Hz and lower. Without knowing the cab specs that's all I can offer. If I was using that driver I'd ignore the WinISD default and go with 30L per driver and 45Hz tuning. If you did use the WinISD default making the port(s) long enough to get to 45Hz tuning would be better, and since the net box volume should be smaller as well you've got the room for it.

And that's why the riders for major touring acts specify Ampeg SVT.

It's simple, whoever bought the rig wasn't a bass player. 😒

You need a cable with 1/4" on one end and Speakon on the other. What's labeled as Direct Output goes to a mixing console, not a speaker. Read the manuals. If you don't have them do a search to find them. BTW, you're in the wrong forum. This is the PA section. 😒

A perfect example of why I stopped going there 13 years ago. It's like watching the Gallaudet University Marching Band, led by Stevie Wonder as the Drum Major. 🤥

Normally I'd agree there, but...the SP212 isobaric configuration means that while it has two twelves it only has the output of a one twelve. A proper 212 will give the OP what he needs, save the SP212 for those gigs where it's enough on its own.

A few items of disagreement. First off, he loaded that cab with replacement Celestions, so what the frequency response is one cannot say. Second, most of the power with electric bass is in the 2nd and 3rd harmonics, so when you play a 41 Hz open E what's mainly there is 82 and 123 Hz. By and large a speaker f3 of 50 Hz is sufficient, even for drop tuning. The SVT 810 f3 is 58 Hz. And lastly where hearing yourself is concerned that's mainly in the upper midbass through the midrange, roughly 200 Hz to 2kHz. As for "In terms of the angled / stacked speaker cabs, I’d have to disagree in my experience. The only times I’ve done that I’ve hated the sound - too harsh and right behind my head." when you aim the cab at your head rather than your calves you hear what the audience hears. If you don't like what you hear neither will they. The EQ should be set so that it sounds good on the speaker axis, not 30 degrees or more off axis. To remove the room from the equation I always walk out onto the dance floor for sound check, adjusting the EQ so that it sounds good there. If that results in less than optimal tone on stage I live with it, I'm playing for their enjoyment, not my own.