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Peter Larsen[_3_] Peter Larsen[_3_] is offline
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Default What's with all these new SIXohm Stereo Speakers coming out?!

skrev i en meddelelse
...

geoff wrote: "- show quoted text -
No. 4 or 8 are the common specs, but the spec is for the minimum load
impedance, so ann amp specced at 8 ohms *may* have trouble with a 6 ohm
load on peaks, but a 4 ohm output won't have any problem at all..


And 16 doesn't matter - if your amp will do the lower ones, it'll be
just fine with a lesser load (= higher Z).


geoff "


So you're saying that I can safely hook up speakers with a 4ohm
sticker on the back to my 8-16ohm receiver, but not a 6ohm.


Your 8 to 16 ohm receiver is probably spec'ed like that because of the cost
of iron and electrolytic capacitors required for a proper powersupply.

I am however not making any guarantee of what it will and will not tolerate,
generally a transistor amplifier comes with circuitry to protect it from
excessive current demand. There are idiotic exceptions, but if the required
protection circuit messes unduly with the sound then the output transistors
were chosen to fit the budget from the sales department rather than the
design requirements.

Generally for an amplifier for home use I'd expect 60 percent more output
power specified for each halving of load impedance because that is the
design choice that _tends_ to allow largest unclipped peak power, no promise
made.

Way back in time somebody tested output power of a number of large power
amplifiers in real loudspeaker loads, I think the worst result was held by a
300 watt amplifier that went into current limiting at 11 watts in a real
world loudspeaker, I also think I remember the brand but they probably do
not make them like that now so it is intentionally omitted.

Clear as mud to me, but I'll trust you on this.


Lower Z = higher load (current demand).

Kind regards

Peter Larsen