Speaker sensitivity vs SQ

bdp24,

I agree with you about the relative merits of Soundlab electrostatic speakers vs. the Altec Voice of the Theater speaker.  The Altec tonal coloration is way too unnatural for my taste as well.  At one time I considered buying Soundlab speakers.  But, while most of the commercially available compression driver systems suffer from too much tonal issues for my taste, I've heard many custom systems that sound very good; I ended up with such a system.

I feel the same way about many other high efficiency speaker types, such as full range single driver systems.  I ultimately don't like their tonal balance and rough frequency response (notable exceptions are Charney Audio and certain Voxativ models).

I like some systems that use "fullrange" drivers as wide range drivers in multi-way systems.  In some, a woofer supplements the fullrange driver, in others, a tweeter is added on top.  An example is the Soundkaos Model 42 (fullrange driver plus a Raal ribbon tweeer on top).  My favorite system utilizes an old Jensen M10 fieldcoil driver (13" fullrange driver) in an open back cabinet (open baffle) operating full range, but with a first order high pass crossover to a tweeter supplementing the single driver (the system I heard had a Jensen RP 302 tweeter, but, I am told that a Western Electric fieldcoil 597 driver is better).

Pa speakers are much more sensitive than hifi speakers, but produce more ditstortion and do not have the same frequency range. To compensate they require active filtering and subwoofers. Making a sensitive speaker isn't that complicated: a woofer with a stiffer suspension (= less lower frequency) and a compression horn tweeter (= more distortion). A pa speaker with the sensitivity of an average  hifi speaker would require a truck full of amplifiers to achieve the same decibels. That's why in sound reinforcement only the max db level of a speaker is most  important. for each 3 db more, the amplifier power has to be doubled!

@larryi,

You may wanna add Tannoy Canterbury Prestige GR speaker to your list of speakers that has exemplified themselves in achieving excellent tonal balance from a single driver.

The Canterbury’s sports a 15-inch dual concentric single chassis driver that incorporates two separate drive units, integrated into one. If you like, you can further read about the merits of dual concentric driver on Tannoy website. Here I wanted to express briefly, the frequency response from 15” driver is pretty flat throughout the entire audible frequency range. The Canterbury’s are excellent speakers capable of delivering very detailed, integrated, dynamic and warm sound. I also dig their traditional look with exquisite birch plywood cabinetry and champagne gold metalwork :-)

@tomic601 asked:  

"are you 3D printing the waveguide?"  

No. I looked into it and concluded that was impractical. The piece is 22" in diameter.

Duke

Aside from your personal likes dislikes in speakers the main advantage of Highly efficient speakers (> 95 dB  with 1 watt at 1 meter) is the greater dynamics that can be achieved.  Doubling the power of your amplifier will only give you a 3Db gain in SPL.  Lets take a look at the power requirements for a couple of speakers,  Setting the max SPL at 116 Db. the B&W 603 S2 is rated at 88.5 DB @ 1 watt input.  To produce 116 Db you will need a 1Kw amp.  My old Altec A7-500's are rated at 103 Db at 1 watt and can Produce 116 dB with a little over 16 watts.  To my ear this is why some speakers sound muted/sluggish on rim shots and other sounds that require fast response.
disclaimer the math is approximant but close. My personal system uses a set of speakers that are rated at 84dB at 1 watt and my power amp is rated at 1Kw RMS and tests to 1.1 Kw/channel both channels operating..   I can only say that switching from a MC2100 to the larger amp was like cleaning a dirty windshild and bass is tight as a drum pun intended.