Are subwoofer drivers okay for usage in a tower? They would obviously only take the low frequencies. If so, do they need their own separate cabinet from the other drivers?
@ Yes, each driver which does not have a sealed back needs to be physically isolated from the others. Why? Well, imagine a sealed cabinet with a powered big woofer and a smaller open-back midrange. The woofer moves IN. That pressurizes the cabinet, which tries to push the midrange cone OUT. They will thus fight each other unless isolated.
If there are three drivers in the tower, with an rms rating of 40, 50, and 60 watts, would the tower be rated for the average rms (50 watts) or total (150 watts)? Building on that last question, do the rms ratings have to be super close to perform well?
@ Sorry, but let me tell you as a loudspeaker engineer that speaker power ratings are pretty meaningless. Some companies do stringent testing before assigning those numbers, but any given piece of music and cabinet design etc may not match that. Plus, many cheaper companies just put inflated numbers to appeal to ignorant consumers.
"Head_Unit’s Rules Of Protection" are:
1) If when things start to sound distorted or odd you TURN IT DOWN, you are unlikely to ever break anything.
2) If you constantly "turn it up to 11"
you will break something.
NOTE: the size and power ratings of the speakers and amp do not affect rules 1 and 2. (In any case, specs for amps are often not thorough and for speakers pretty meaningless).
Now as far as if your amp is big enough, that is another matter. How loud do you want to play (with clean sound)? What speakers do you have? Is there a sub? Describe the room and what it connects to. Because you can definitely have too small an amp if you have inefficient speakers in a big space and you want to play loud.
@ That said, if you have a specific combination you can always ask if folks think they are compatible power-handling wise; likewise the amplifiers. The collection of "tribal wisdom" can help elucidate clarity in these murky audio waters.
If so, can that be bypassed by making tower a sealed cabinet?
@ Ported cabinets use the port to resonate with the air in the cabinet, kind of like a car wheel hanging on the springs. This means around the port frequency the woofer moves little and the air in the port moves a lot. So a port can extent the bass and reduce excursion. Now in life there is no free lunch, so the problem is that at lower frequencies the port no longer resonates and just acts like a leak.
@ By comparison, at lower and lower frequencies the sealed box limits the excursion of the woofer.
@ So the ported speakers moves less around the port frequency, but below that bottoms out more easily compared to the sealed speaker.
@ As for the sound, the ported box can have stronger bass at the expense of worse transient response. In other words, each musical note won't stop and start as cleanly due to the resonance. How "worse" this actually sounds depends on the tuning and a zillion other factors.
Lastly how expensive should I expect a pair of diy towers to set me back?
@ Send me the money, and I'll get you a great set of parts.
@ Now if you want to be boring and do it yourself, then what you spend could vary a lot. A simple cheap 2-way could be I dunno, $200 if you made cabinets yourself out of MDF. From there the sky is the limit
@ As for the crossover, those are simply not well designable unless you have a way to actually measure the drivers. You cannot rely on factory measurements, as each factory uses different equipment and techniques. (If you used all the same brand of drivers and their frequency AND impedance measurements all had the same format then maybe you could, if they had raw importable data available. You'd need software that could import the data and simulate the crossover).
@ It's a big learning curve and some expense to do all that, so it is far simpler to get a driver+crossover kit. But if you want to go for it, hey, good luck! You can get help here.
@ You can get a premade cabinet with many kits, or make your own.
@ I second this, and third it. Vance is not only a nice guy, he is super smart and has measured by now literally a ton of speakers.
@ A note of positive hope: whatever speaker you build, you'll always hear something new out of the music. So go for it!