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          Seas Prestige 27TDFC ($51)          —     Seas Excel T25CF Millennium ($271)
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3200

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The long, tall spike in each of these spectrograms is the single frequency sent to the speaker driver. It’s the only frequency it should be producing. As can be seen, drivers aren’t perfect. They all produce some harmonic distortion, i.e., frequencies which are multiples of the fundamental. When you look at the spectrograms, you’ll see other shorter lines popping up. Those lines are the harmonics. The more of them and the taller they are, the more harmonic distortion. Second harmonic (the first multiple to the right) is relatively benign even at 40 dB below the fundamental (1%). However, as the harmonics get higher, they are easier to hear, and therefore, the lower their level needs to be, preferably 60 dB or more below the signal, to be inaudible. Both of these tweeters are excellent. Both sound clean. Carefully comparing the two shows the $51 27 TDFC consistently has less 3rd, 4th & 5th harmonic distortion than it’s very expensive big brother. Makes ya wonder.

Makes me glad I did my homework before choosing a tweeter for the Parallel Audio Project. I could have fallen for the Millennium driver. It has an outstanding reputation and it’s beautiful to look at. I could have fallen for a number of other highly regarded, pricey, top-of-the-line tweeters with good reputations and good looks. But I took my time, because at the time I didn’t have any test equipment except for an SPL meter (an uncalibrated one at that), nor the desire to buy and test numerous drivers. After scrutinizing the linear response, distortion and cumulative spectral decay of dozens of drivers, I was surprised to find that there are a few moderately priced drivers of all types, not just tweeters, which perform as well or better than specialty, exotic, or stratospherically priced models. And now that I’ve tested these two for myself, it confirms what I had found, and I’m still surprised. Facts trump marketing. Go tweet that.

To learn more visit [Parallel Audio]

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Canned Music

no preservatives added

What is live? What is canned?

Well, that’s easy. Live is when the musicians are upfront, in person, performing right here, right now. Canned is music that was recorded and later replayed through a sound system.

And that’s what everybody thinks. Think again. Tell me, what’s the difference between hearing a recording through a sound system or hearing live musicians through a sound system?

Most performances today are miked, mixed, amplified, and played through loudspeakers. You might think, because the musicians are performing in the flesh, on the spot, it would be fair to say, it’s live. But let’s face the music, it’s canned. The only step that’s missing is the recording. (And often parts of what you hear at a live performance are prerecorded.) The sound of real, living musicians, playing real, acoustic instruments is being filtered. They may be performing in the moment, but the sound is not live. It’s aliveness has been squeezed through microphones and wires and electronics, leaving us merely with realtime canned music.

That’s point number one. Point number two is this. The only music performances most people experience today are realtime canned concerts. They’ve never heard, or too rarely hear, the sound of unprocessed music. Just yesterday I was talking to a young woman who went to a performance of the Verdi opera, Rigoletto. She commented that it was not miked. The Metropolitan Opera, miked!? Of course not, but in her experience, everything is amplified. She, along with the majority of concert goers, only know the sound of sound systems—most of which are not good and/or poorly operated. It’s no wonder there’s so much nonsense going around about the quality of home audio. The only known reference is other artificial sound. Without the real, acoustic reference, there can be no honest judgment of sound quality.

Then there’s the issue of, “this is the way instruments sound, but that is how I wish they would sound.” I witnessed an interesting example of this dichotomy in a demonstration of three recording techniques, wax cylinder, analog tape, and digital. Two musicians participated, a violinist accompanied by a pianist. They played a short piece captured by the horn of the wax cylinder, and two different microphones, one feeding an analog reel-to-reel tape, one to a computer. All three recordings were done simultaneously. After playback the audience voted on their favorite. No surprise that the wax cylinder came in dead last—noisy, scratchy and lacking in both treble and bass. The winner was the analog recording. Hmm. I didn’t like any of them, but that may have been partially due to the playback speakers. The violin sounded reasonably good on both modern techniques, although slightly more alive on the digital, but the piano was bad, really bad, on both—bottom heavy and muddy—not at all realistic sounding. That bass heavy muddiness was especially evident on the analog recording. So how did the analog recording get the most votes? The violinist summed it up neatly when he was asked to comment on his favorite. Referring to the analog recording he said, “That’s how I would like to sound.” The tonal quality he strives to achieve, not his actual sound, was the reason he preferred the tape. Had he listened to the piano, instead of only to himself, the murky sound would have necessitated qualifying his preference. Curiously, the pianist’s opinion was not queried.

There you have it. If one doesn’t know the sound of acoustic instruments first hand, under varying conditions, or if one has a rosy, idealized sound in mind, there’s going to be disagreement about when reproduced music sounds right.

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