lauck@bergil.DEC (01/14/85)
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I guess I'm not that much of a purist. I'd rather listen to music via
fuses than to silence. I'd also rather have any blown components replaced
under warranty. Thus I have NOT bypassed the internal fuses in my
VSP LABS Gold Edition (200watt per channel) amplifier, nor have I
bypassed the fuses in my Snell Model A series II speakers.
Since last April when I replaced my aging and underpowered MacIntosh
amplifier with the VSP Gold, I have replaced EVERY speaker fuse, some
several times. In each case it was due to carelessness on my part,
coupled with a certain amount of flakey connectors. Perhaps I'm more
spastic than others, but it is awefully easy to screw up. Example: my
power down sequence is the following: 1) preamp gain to zero, 2) power
off the amp, 3) wait 30 seconds, 4) power off the preamp. Without the
delay or the zero gain I blow speaker fuses.
I haven't repeated any particular type of screw-up, I just keep finding
new ones. Anyhow, what if I had a power failure while playing music?
With a different system, e.g. more drivers or less amplifier power, and
possibly a power control system or a preamp with effective power on/off
muting, I would think about removing fuses, but I doubt I would do it. The
fuses were engineered into my components for a reason and I wouldn't want
to remove them. Perhaps in the future I will procure components which don't
need fuses.
Tony Lauck
decvax!decwrl!rhea!bergil!lauckwmartin@brl-tgr.ARPA (Will Martin ) (01/22/85)
> Example: my > power down sequence is the following: 1) preamp gain to zero, 2) power > off the amp, 3) wait 30 seconds, 4) power off the preamp. Without the > delay or the zero gain I blow speaker fuses. > > Tony Lauck > decvax!decwrl!rhea!bergil!lauck This is interesting; does this sequence also apply when there is a signal continuing through the system? For example, if you have a tuner playing and it is NOT turned off, so you get signal through the power amp as it discharges its capacitors? This is how I normally switch off my system; I have everything plugged into a power strip, but never use that main switch -- my preamp power switch controls its switched outlets but not the preamp itself, which is modified to be always on. I hit the preamp power switch, which cuts the power to the power amp and a couple other units. Let's assume I have a tuner playing, which is controlled by its own power switch. The tuner signal continues to be fed through the always-on preamp to the shut-off power amp, which uses up the remaining power in its capacitors by amplifying the signal in a dwindling fashion for several seconds, and winds down to nothing. I then turn off that tuner and anything else that needs turning off. (This isn't done that way for any real reason, it's just the habit I've gotten into. My speakers are Klipschorns, which seem indestructable. They weren't even bothered when a capacitor self-destructed on an earlier power amp; made a LOUD boom, though!) What I'm wondering is whether the fact that your power amp capacitors are still charged when you power off your preamp causes any turn-off thump of the preamp to be amplified and fed to the speakers? If you drained your power amp by playing a signal through it continuously as you turn it off and let it die out natually, when you turn off your preamp there won't be any oomph or power left in the shut-off power amp to do any amplication of that preamp turn-off thump. I guess letting a turned-off power amp sit for a while lets at least some of the power drain out of the capacitors also, so that would have a similar effect. (This is assuming no fancy circuits in any of this gear, with relays or crowbars or whatever, which would cut off signal when power is cut, or short things to ground, or whatever...) Regards, Will Martin USENET: seismo!brl-bmd!wmartin or ARPA/MILNET: wmartin@almsa-1.ARPA