Why is good, deep bass so difficult? - Myths and their Busters

Good speakers in a good room sound a lot more satisfying than top end speakers in a mediocre room.

Many people have no idea how good even 2-way systems can be properly set up. Proper room acoustics can make them sound enormous.

Best,

E

There are a lot of good points here. . . I thought my 20.1 Maggies went low until I got the subs set up and dialed in. The difference is incredible. Friends come over and expect to be blown from their seats but with proper speaker placement, using multiple subs, and room correction all they get is an tuneful accurate sound. The support that the subs give to music is very satisfying. After I get asked to turn it up two or three times and get close to symphonic concert levels comments are that the system is so "clear." They don't understand how it can be so loud but not hurt their ears. While I don't think people need to be acoustical engineers or physicists to get the best from their systems understanding basics can make a huge impact. Room interactions are almost as important as the system itself in my opinion. 

So here are a few things to consider.

1. Most woofers double. 40 Hz turns quickly to 80 Hz. 
2. The law of physics would dictate that a 10" woofer will not keep up with a 6" midrange. Too much mass. They must use very stiff suspensions to bring them back to neutral position after each excursion.
3. Woofers are screwed into a large piece of MDF. The very back and forth movement of the diaphragm causes that piece of MDF to resonate. 
4. Massive objects resonate at frequencies that are hard, very hard to deal with.

My system for the three years was using stereo subs and a DSPeaker Antimode 2.0 to do the room correction . I was happy with my bass response until I heard a distributed bass setup at a listening session at another audio files home .Back to the drawing board . I added in two more subs . Installed hi pass caps in my amps used my DSPeakers crossover and stereo sub correction function and good old listening to adjust the levels and now have the best most even bass response in my listening room to date .  Duke is right in this case more subs is less boom in the room .            

That a 12/15" woofer is "slow" is a myth, I’m sorry, I’ve proven it over and over again and much smarter physicists than I have explained it. The real issue is that they produce too much deep bass, which integrates poorly in a room without attention. Give me bass traps, EQ and a pair of 15-18" woofers and I’ll scare you right out of the room they are so fast.

As I recall, the large woofers have to move fractions of the small woofer, and have much larger motors, so any issues of mass are more than offset by efficiency (in regards to displacement vs. Hz). Rule of thumb I learned a long time ago, and I may misremember, is that doubling the drivers is the equivalent of using a single driver 2" larger.

So for instance, 2x 8" = 1 x 10" driver. 2 x 10" = 1 x 12" and so forth.

Point is, there is just no substitute for raw surface area if you want deep and low distortion bass. As I noted at the first posting that started this thread, I can really see why this myth is so attractive.

Now, about movement, yeah, you have something, not only the baffle, but the entire speaker can move due to the woofer forces. Cheap fix: Add weights to the top of a speaker. Like 20 lbs at a time. :)

Best,

E