TS > TS > LS> Well, how well does the crown 10kw amp old up
TS > TS > I don't recall.  Note that it's rated at 2/3 of an ohm, not TS > 8
TS > ohms.  Obviously they're good enough for the target
TS > TS > customer mil contractors.
TS > LS> Quite stable, more stable than the Crest Audio 1000x series.
TS > Note that those Crown amps are audio amps, but the intended
TS > use is NOT to feed audio to speakers.  It's to see what
TS > might fail from resonant or other undamped vibration in
TS > electronic or mechanical structures.
Hehehe.  Well, i just like an overdamped amplifier, it gives my spinal cord a 
bit more traction than i would probably want.
TS > LS> As you know, or should know, the impedance of a
TS > LS> speaker is a reactive load, never stays at one
TS > LS> impedance.  I could visually see that happen over the
TS > As you might have noted by now, I work with RF as well as
TS > audio.  In tuned RF circuits, it's more normal to use an
TS > impedance bridge, vector voltmeter, or network analyzer to
TS > tune critical matching points in a transmission system for
TS > matched resistive elements of impedance, and to make
TS > reactive elements negligible at a carrier frequency and
TS > minimal and symmetrical around it.
TS > In speakers you do not have a reactive load.  You have a
TS > load some element of which is reactive, operating over a
TS > wide enough band and with transient needs such that it's
TS > not practical to use matching networks.
TS > LS> woofers at 800 watts RMS near clipping from my amps
TS > LS> (8 ohms, dipping to 3 ohms at 50 hz, a characteristic
TS > LS> that Yamaha would not explain).
TS > Many speakers tend to have a resistive and inductive
TS > reactance component that contribute about equally to the
TS > total Z.  In a woofer, the resistive element's value is
TS > approached as you go down in frequency approaching DC,
TS > where the X(L) drops to zero.  The speaker when in use acts
TS > as a motor/generator, and often has a dynamic change in
TS > impedance based on its mechanical construction and loading
TS > from the enclosure, those mechanical factors changing the
TS > electrical load presented to the amp based on voice coil
TS > position and motion.
TS > You're unlikely to see full specs published on most
TS > speakers, as the details can get a bit complex.  With solid
TS > state design, it's easiest to just use overkill damping
TS > factors and assume a good amp can provide current wasted on
TS > reactive load demands that don't transfer real power.
TS > OTOH, resistive loading by a voice coil may transfer more
TS > energy to heat as magnetic fields are generated to move the
TS > voice coil than reactive current loading.  There's a
TS > certain amount of art to transducer design, not readily
TS > definable in scientific terms.
TS > LS> Current gain from the amp, not the wire!.  My amps can carry 100
TS > amperes
TS > Modern solid state amps are designed as voltage gain
TS > circuits, whose outputs are nominal zero ohm current
TS > sources.  If such amp designs were based on current gain,
TS > the output would bouce all over the place based on load
TS > impedance variations.  Gain is the ratio of in/out.  In
TS > solid state electronics, the Hfe of a transistor is the
TS > most common application of current gain.  Some industrial
TS > telemetry uses current loops for noise immunity.  That's
TS > not the term you apparently mean here.  It sounds like you
TS > mean to say peak and sustained current sourcing capacity.
TS > LS> per channel continuous, 200 amperes peak.  I tested
TS > LS> this out about 20 times a year when the speaker wires
TS > LS> short circuited and then melted the insulation on my 10 guage
TS > cabling.
TS > Unless you defeated normal AC line protective devices, how
TS > did you sustain 100 amperes?
Simple, plugged the amp into a 25 ampere 120 volt plug, 120 volts dipped to 
90 volts, and that's what i measured using an ammeter in parallel with a 8 
ohm speaker.  The speaker did not like it, i measured 167 volts at 100 ampers 
into the speaker.  I noticed amps are getting very efficient, 75 percent 
efficiency rating is on all my amplifiers with this class AB dual rail 
tem.
TS > TS > #6 or 8 wire would likely survive.  #1 Cu would be required TS > 
or
TS > that current under NEC if it were house wiring.
TS > TS > Allowable voltage drop under NEC translates to undesirable TS >
TS > damping factor degredation for audio.
TS > LS> Hmmmm.  NEC standards do not come into play on speaker
TS > LS> cables, unless you are *certain* about the current
TS > LS> gain coming out of the amp *steadily and continuously*.
TS > NEC standards do apply to speaker wiring as is being
TS > discussed, and these power levels don't receive low voltage
TS > code benefits.  Code regulates cable types for various
TS > installations, plenum exposures, etc.  As to use of high
TS > voltage code standards, they're only a guideline for safe
TS > wire heating.  Damping factor would be quite poor at the
TS > voltage drops allowed by NEC for 120 VAC, and so usually
TS > you want wire that well exceeds sizes where heating is a
TS > problem.
Hmmm, i will get back to you in a moment (1 day apart from this message), i 
used up my 240 minutes/day.
Laszlo Sokolai
Team ANTI-Windows95/PRO-OS2/PRO-Unix
lsokolai@bbs42.com
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