sjc@angband.UUCP (Steve Correll) (02/04/85)
> Consider the electrical signal flowing through the wire as a flow > of water through a pipe. If the pipe is too small, then the flow > of water will be restricted. If the pipe is large then there is > little restriction to the flow. If an electrical signal's flow is > restricted it will disturb the signal received by the speaker... Basically, you're correct. To put it another way, everything that conducts current "impedes" the flow somewhat. When current must flow through two conductors in a row (first a cable and then a speaker), the conductor with the most impedance soaks up the most power. If the cable had zero impedance, the speaker would get all the amplifier's power; but if the cable and the speaker had the same impedance, half of the power would be wasted in the cable. Any practical wire has much less impedance than a speaker, so that's not the problem. But the impedance of a speaker varies drastically with frequency. An "8 ohm" speaker may vary from 2 ohms in the treble to 20 ohms in the bass. The impedance of a cable is relatively constant by comparison, so (for that hypothetical speaker) the cable will steal a bigger share of the power in the treble than in the bass, making your speaker sound weak in the treble. All else being equal, thin wires exhibit more impedance than thick ones. A thick enough wire steals so little power that you don't notice the variation with frequency. > I've heard that some people solder there speaker wires (and other > wires?) to the connecting posts as they feel it gives a better contact > and the loss of flexibility is worth the improved performance. That's not unreasonable. Poor connections can degrade the signal more than the oxygen content, capacitance, or brand name of your cables. If you want to try soldering, use 60%-tin/40%-lead solder (the solder will isolate the wires from air, so gold isn't necessary) having a rosin core (*not* acid core). Use an ordinary soldering gun or pencil whose tip doesn't exceed about 3/16 inch. The secrets of soldering (if you don't already know them) are (1) scrape the metal surfaces very clean (2) rig them so they can't wiggle--the human hand can't hold them steady enough (3) get them very hot (4) apply solder to the metal surfaces, not to the tip of the pencil or gun (5) remove the tip after the solder has flowed around the joint and (6) don't wiggle anything till the solder has cooled completely. Poor connections between the phono cartridge and amplifier can also cause problems because the signal is so weak and susceptible to radio-frequency interference; the connection can act like a diode and demodulate the RFI. A less drastic solution here is to buy the cheapest gold-connector cables you can find (e.g. Radio Shack). Periodically unplug them and scrape clean the non-gold connectors on your equipment. > I was a member of the RCA Music Club and the International Preview > Society. I quit both of them during the last year. Both sent me > offers to become 'Half Price Member for Life'... I don't know whether this is standard policy, but you're not the first to encounter it. -- --Steve Correll sjc@s1-c.ARPA, ...!decvax!decwrl!mordor!sjc, or ...!ucbvax!dual!mordor!sjc