The Non-tweaker's Guide To Tweaks Page 3

Speaker Tweaks
Just the usual things: keep them away from walls and corners (unless they're specifically designed for such placement); use sturdy spiked stands or Tiptoes if appropriate; experiment with varying the vertical and horizontal angles; use the best cables you can afford; use spade lugs rather than banana plugs; if you have to use bananas, use ones with a high-pressure spreading action (eg, WBT). Almost every speaker I've heard sounds better with the grille cloth removed; depending on the manner in which the grille is attached and depending on how acceptable you find the appearance of the speaker sans grille, removal of the grille is probably the most universally applicable speaker tweak.

System Tweaks
AC plug orientation: This is quite a well-known tweak, and, with some components (not all), the effect is quite substantial. The procedure is to disconnect the component (CD player, preamp, etc.) from the rest of the system, turn it on, measure the residual voltage appearing on the chassis (use any voltmeter, connect the black probe to a known ground, and touch the red probe to a metal part of the chassis), pull out the AC plug and plug it in the opposite way, measure the chassis voltage again, and leave the plug in the orientation that resulted in a lower chassis voltage, marking the orientation for future reference. The most noticeable effect of going through this procedure for every component in the system is improved midbass clarity (reduced intermodulation with hum, I guess).

Clark Johnsen, author of The Wood Effect (see below), suggests listening to the system with all the AC plugs oriented for minimum chassis voltage, reversing all the plugs and listening again, then using the orientation that sounds better. Although I don't understand why the reversed orientation should sound better, it would be at least instructive to listen to the contrast. (In my system, the "correct" orientation does sound better.)

AC line cords, speaker cables, interconnects: I won't get into the issue of the role of cables in determining sound beyond saying that, indeed, they can play an important role, but I want to say something about the positioning of these cables. This is another area that one can easily get paranoid/compulsive about, but I think it's reasonable to keep AC cords away from interconnects and speaker cables whenever possible, also interconnects and speaker cables from each other, crossing them at right angles if necessary.

Finally, although much too expensive to be considered a tweak, the Tice Power Block is a great product that really does work as claimed, bringing about a significant cleaning up of AC power, with major gains in sound quality.

Absolute polarity: Clark Johnsen's The Wood Effect (footnote 1) reviews evidence and opinion on the importance of this variable. Absolute polarity (sometimes called absolute phase) is best thought of as a system characteristic, and refers to whether a sound that originally started out as compression followed by rarefaction (ie, positive then negative) is reproduced that way rather than as rarefaction followed by compression (ie, negative then positive). Given components either maintain or reverse absolute polarity, with the result that the system as a whole may be in correct polarity for one source (eg, CD player) but not for another (eg, phono). Recordings themselves may be recorded in or out of absolute polarity, and, to make things even more complicated, polarity may not be the same for the whole recording, or may vary for different instruments in a multi-track mix.

The audibility of absolute polarity differences under laboratory conditions with test signals has been demonstrated by Stanley Lipshitz and others, but there is some controversy about how important (as opposed to statistically significant) the effect is under normal listening conditions with less than purist recordings, and about how sensitive different people are to reversal of polarity. As far as I'm concerned, although I can hear the difference with some recordings (the Chesky Test CD provides a good demonstration), I'm not driven to a fit of frenzy whenever a reversed-polarity recording assaults my ears. I certainly would not want to switch speaker cables (Johnsen suggests this is more effective than electronic signal reversal) whenever I suspect the recording to be of the wrong polarity.

So, why include maintenance of absolute polarity as a recommended tweak? Well, it costs nothing, and, other things being equal, it's better to have the system in rather than out of absolute polarity. (Of course, this does not guarantee that all recordings will therefore be polarity-correct...) The Chesky Test CD is ideal for determining which connection maintains absolute polarity; you then have to check if an LP known to have been recorded in correct polarity sounds better with the connections as set for CD or in reversed configuration. If the reversed sounds better for LP, the cartridge connections should be reversed. Some preamps have an absolute-polarity reversal switch; owners of these preamps can play with this parameter to their hearts' content. My Aragon D2A digital converter has remote-controlled polarity reversal; although it's useful for making some critical comparisons, I find it leads me to listen for sound rather than to the music (the audiophile's Achilles' heel).



Footnote 1: Available from The Audio Advisor (800 942-0220) or direct from the publisher, The Modern Audio Association, 23 Stillings Street, Boston, MA 02210, Tel: (617) 357-8040, for $7.95 plus $1.05 shipping and handling.
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