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Another thought

0

Posted by Al Sekela on July 6, 2004 at 08:19:13

In Reply to: Cable changes posted by steve on July 2, 2004 at 06:53:11:

Do your speakers have Zoebel networks at the inputs? It is also possible that there is
electrical ringing taking place in the speaker cables. Some speakers appear to have residual
inductance at very high frequencies, higher than the audio band but not what most would
consider RF. They become open circuit terminations to the cables at elevated frequencies,
and this can lead to ringing. A Zoebel network at the speaker would consist of a 10 ohm
noninductive resistor in series with a 0.01 mFd capacitor.

Your amps almost certainly contain such networks to provide protection in the event of
output tube failure, but a speaker cable with good high frequency transmission
characteristics should have some means for damping the out-of-band ringing.

An alternative would be to place Power Wraps around your speaker cables. I put a pair of
standard ones on the short cables from my MA-1s to the Speltz ZEROs at the inputs to my
mid/tweeter crossovers, with definite smoothing of male vocals and similar midrange
voices.

Finally, be sure your cables do not rest upon the floor, especially if it is wood, laminate, or
synthetic carpet. Lifting most speaker cables by an inch or so from such coverings makes a
big improvement in the liveliness and sound-stage. However, the objects used to lift the
cables should not have mechanical resonances. I've gone from ceramic tile pieces, which
are naturally damped by resting on carpet but not very tall, to optical glass prism blanks
(because I found them in a salvage yard) damped with Dynamat and glued to wood riser
blocks. Before I applied the damping and cement, they rang like little bells and added
severe treble harshness.

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