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


This is a theme that goes round and round and round on Audiogon. While looking for good sources, I found a consultancy (Acoustic Frontiers) offering a book and links:

http://www.acousticfrontiers.com/guide-to-bass-optimization/?utm_source=CTA

Interestingly: AF is in Fairfax, CA, home to Fritz Speakers. I really have to go visit Fairfax!

And a link to two great articles over at sound and vision:

https://www.soundandvision.com/content/schroeder-frequency-show-and-tell-part-1
https://www.soundandvision.com/content/schroeder-frequency-show-and-tell-part-2

Every audiophile who is dissatisfied with the bass in their room should read these free resources.

Let me state unequivocally, deep bass is difficult for the average consumer. Most audiophiles are better off with bass limited speakers, or satellite/subwoofer systems. The former limits the danger you can get into. The latter has the most chance of success IF PROPERLY IMPLEMENTED.

The idea that large drivers/subs are slow is a complete and utter myth. Same for bass reflex. The issue is not the speed of the drivers. The issue is usually that the deeper a speaker goes the more it excites room modes, which the audiophile is then loathe to address.

Anyway, please read away. I look forward to reading comments.
erik_squires

Not a recording studio, but Sterling Sound Mastering in NYC have three pair of Rythmik F15 Direct Servo Feedback Subwoofers in their monitor systems, each with a 15" woofer. Killer bass. Rythmik owner/designer Brian Ding has been asked about the question of woofer diameter versus "speed", and his answer is that his 8" and 12" woofers are no "faster" than his 15", but that the 15" has higher maximum SPL output. Of course, the woofers in his Rythmik subs are servo-feedback controlled.

I have both 12" and 15" Rythmik Subs, but the woofer size is the least important difference between the two. The 12" are used in pairs mounted in Open Baffle H-frames, the 15" in a 4cu.ft. sealed enclosure. OB subs are very different sounding than both sealed and ported, for a number of reasons I won't go into here, but the point is the size of their woofers is not responsible for the difference in sound between the two.

I don't think your 15" sub will keep up with your 6.5" midrange. Not much cohesiveness. To each his own.
Imagine how much trouble his 6.5" midrange has keeping up with his 2" tweeter :)

"the woofers in his Rythmik subs are servo-feedback controlled"

Exactly, because to maintain accuracy and to stay in pace with the "lighter" drivers in the mains, you need a near realtime (servo) feedback mechanism to modulate the movement of the heavier driver.

The servo-controlled woofers in Rythmik subs are described as "stopping on a dime". I liken them to a high-torque engine---very responsive. They "track" the signal very closely; no overhang/overshoot, no bloat or plumpness. Lean and clean!