Choreboy wrote:
David Martel wrote:

Steve,

Inexpensive 16 ga. "zip" cord from any hardware store makes good speaker
wire. Really, really long runs of wire can affect the performance and sound
but if you keep it under 100' you should be OK.

Dave M.


The problem is resonance. Many TVs have cabinets that resonate at
varous frequencies. The sound from internal speakers will be noisy and
distorted.

The resonance of a room can make a tape recording sound terrible. For
ten years I listened to Koss Pro4AA headphones to avoid the resonance of
room acoustics. Those phones usually performed better than speakers.
In an ideal situation, good speakers could be better; the sound could be
fuller and less harsh.

Then I read about damping factor. It was defined as the ratio between
speaker impedance and amplifier impedance. Feeding speakers with a
relatively low impedance can make a difference because speakers
resonate. They are more efficient at resonant frequencies, and their
impedance is proportionately higher.

My phones were 32 ohms, but receivers were usually designed to feed
headphones through 220 ohms. At frequencies where the impedance was 32
ohms, my phones would be getting 1/8 the voltage from the amplifier.
If, for example, they resonated at 500 and 2000 Hz and their impedance
rose to 220, they'd be getting 4 times more voltage, or half the amp's
voltage. In that case, feeding the phones through 220 ohms would make
500 and 2000 Hz harsh and other frequencies relatively weak.

It cost me only a few cents to change the circuit to a voltage divider
with an output impedance of 0.5 ohm. This meant the voltage at my
phones would be pretty constant for all audible frequencies. What a
difference! The phones were clearer, less harsh, and had a wider, more
even response.

I didn't have to go as low as 0.5 ohm. If I'd built a 3.2-ohm divider,
that would have given me a damping factor of 10 with my 32-ohm phones.
That would probably have been fine.

18-gage copper wire has 6.5 ohms per 1000 feet. If your speaker were 50
feet from the amp, that would be 100 feet of wire or 0.65 ohms. For a
6-ohm speaker, I imagine that would sound fine to most people.

28-gage copper has 66 ohms per 1000 feet. For a speaker 50 feet from
the amp, the resistance would be about the same as the impedance of a
6-ohm speaker. I imagine the difference would be audible.

18 gage sounds big enough for speakers 50 feet away, but the OP might
want to test it by hooking up one speaker through the wire he intends to
use, then using to balance control to see if it still sounds as good as
the other speaker.

The insulation on zip cord usually has a ridge along one of the
conductors. That's how I keep my polarity straight with using it for loudspeakers.

Who cares what it sounds like as long as it is loud.