15 Aug
2009
15 Aug
'09
6:44 p.m.
On Sat, Aug 15, 2009 at 10:10:51PM +0200, Arnold Krille wrote:
For speakers you want the impedances to be about the
same
so the efficiency is high.
No. Power amps have very low output impedance, typically less
than 0.1 ohm. Speakers are voltage-driven. They have to be for
good damping. You can easily 'feel' the difference. Disconnect
a speaker and gently tap the cone, you will feel it's 'soft',
and it may even produce some low frequency tone. Now connect
it to the amp and switch on the amp. The cone will feel quite
'hard'. What you feel now is the low impedance of the amp which
allows it to control the movement of the cone - it makes the
speaker resist any movement that is not driven by the amp.
Ciao,
--
FA
Io lo dico sempre: l'Italia รจ troppo stretta e lunga.