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How well does Zu’s full-range drivers measure Zu's full-range 10.3" driver is amazingly "flat," especially considering its bandwidth is 35Hz to 12 kHz, and that's without electronic manipulation. Designed to be so in hopes of eliminating additional electrical components, crossover parts, impedance matching networks, notch filters and so on which we believe to rob life and body from played back events. We have developed a driver that is capable of over eight octaves of bandwidth, needs no electrical hand-holding and does not introduce beaming problems, harmonic distortions, compression and other dynamic distortions and certainly not Doppler distortions when used in practical, event level, home playback.For reasons unknown to Zu, we think we are a likable bunch of guys, many have been extremely critical of our products, particularly our loudspeakers. Naysayers have by and large challenged Zu on every turn without having touched a Zu loudspeaker, measured it, or listened to it. We at Zu wonder why these armchair engineer feel so impressed to drop their juvenile opinion in public forums; absent credentials and usually completely anonymous. Anyway, to answer the question and get in a bit of bar bangin’ in at the same time I offer the following. (Bangin’ bars: motorcycle lingo for having a good time with your competitor on the race track; car guys call it rubbin' or tradin’ paint). Zu challenger Cdwallace on AudiogoN implies these problems with regard to the Zu Definition: http://forum.audiogon.com/cgi-bin/fr.pl?cspkr&1148220925&openflup&86&4#86 "some single cone problems; 1. Uneven frequency response = less Fidelity 2. The transition from 4pi to 2pi, makes the driver sound as different as two drivers and destroys tone 3. Modulation of high frequencies due to low frequency content. destroys tone and fidelity" The first statement has no meaning as the variables are infinite and understanding limited; people looking to enjoy playback are wise to trust their ears and individual impressions—what is right for one is not right for another; and engineers must have solid practical application with the ideas, devices and theories they postulate on. By frequency response the challenger is referring to amplitude response, efficiency (not Voltage sensitivity) and bandwidth; these are separate but related transducer characteristics as applied to loudspeakers. Measures will vary dramatically depending on measurement technique, equipment, processing (FFT code), signal type (dynamic, steady-state, waveform) and so on. A sincere scientific approach is required if we wish to correlate and advance our understanding of the acquired data. To use tests and measures without defining and adhering to standards is absurd. And you know the word absurd is latin for out of tune.... Generally, based on listening and tests, the majority of single-cone full-range drivers popularly used in hi-fi do have amplitude aberrations, but Zu’s full-range unit is not typical. Zu and contributors spent a considerable amount of time researching and developing the innate amplitude response characteristics, efficiency and bandwidth of the Zu full-range drivers in hopes of eliminating the need to match an electrical loudspeaker level network to it (notch, impedance, all pass, hi or low pass, crossover...). No transducer of any kind is free of noise and distortions, including the Zu. Even so the technically inclined must realize that practical application supports the assertion that Zu’s full-range drivers behave in a linear and accurate fashion. This should also lead the technical thinker to question, “What is the ideal amplitude response in-room vs. open space? Should a loudspeaker system that measures "flat" using an impulse response and FFT processing in open space also measure flat in room? What other techniques should be considered as FFT is considerably older than the vacuum tube? What types of FFT algorithms are employed to acquire the data and so on?” If gated "flat" measures were obtained in-room, accurately reflecting the input signal, which I would contest is almost hopeless, and we were talking about the nature of the single point source sonic event and its development and decay within an enclosed space, say average U.S. living room, would this loudspeaker accurately represent the attack, sustain and decay of music, to use rudimentary musical terms? We should also wonder how important "uneven frequency response" is to the human ear. Consider for example all normal living rooms have amplitude variations of more than 10dB, a minimum intensity difference of ten times. If we assume the transient behavior of a loudspeaker to be amplitude and bandwidth perfect, more or less, and measures so in free space, what will become of the sustain of the note? Will it become overly intense in-room? And the decay, what of it? On the other hand, if a loudspeaker measured more or less "flat" in-room using some steady-state spectrum analyzer, what would become of the transient? How would we use this data and how does it correlate? And this I believe is simply the beginning. Once an engineer or an investigator begins to think in terms of three dimensional space with incredible rates of infinite expansions, acoustic problems can never again be boiled down to such simple statements. For those who wish to increase their understanding of acoustics, psycho-acoustics, nature of sound and "tone" I offer a short list of personal favorite authors that don't get too proof oriented: Helmholtz, Olson, Jeans, Rayleigh, Benade. Need to get some tone in your life? Read "On The Sensations Of Tone" by Helmholtz while listening to Jeff Beck, Eric Johnson, Adrian Belew, James Hunter, Mike Watt, J. Mascis, Zakk Wylde, Hendrix, Django, Page... Tone is different to every guitarist, but every great guitarist gets Tone. All these great guitarists have unique and original styles and sounds yet can all appreciate the others. Zu does its own thing that's for sure. We are engineers, music freaks, inventors, builders, friends, rivals, and some of us are pretty damn good on a dirtbike. |