The_Lhc said:
davedotco said:
If we equate the performance of the Sonos with that of a decent budget amplifier, as the limited figures suggest, then it is fair to say none of these amplifiers will drive 'the very best' small loudspeakers.
Ok, so what is it about "the very best" speakers that makes them difficult to drive? Why can't good speakers have 8 Ohm impedance and high sensitivity (say more than 88dB/W) for example? I've never really understood why good speakers have to be a difficult load. Not least when you go back to my earlier example of low power tube amps that can only really be used with speakers with sensitivities in the 90s. Typically those systems are never cheap, so you'd hope the speakers are reasonably good at what they do?
In this instance clear evidence of this is difficult due to lack of information, so a 'judgement call' is made based on the figures we do have and many years experience.
Yes, it's unfortunate there's so little technical detail available on the Connect:Amp. Hey-ho...
Speakers are strange devices, particularly small ones. The relationship between driver, cabinet and bass extension is well understood but in essence small speakers with sufficient bass extension to be useable will be inefficient. You can use a ported enclosure to help the bass response but, in a small speaker, you throw away mid band output such that the relative output in the bass is increased.
Ie if a 1khz signal produces 90dB and a 50hz produces 84dB then the bass response is, obviously enough -6dB at 50hz. Use the crossover to reduce the 1khz output to 87db and the bass is now -3db at 50hz, much better!
All of this adjustment requires a more complex crossover, one that might often be more difficult for the amplifier to drive, requiring substantial voltage and current output simultaneously. Better amplifiers will, almost by definition, handle these complexities better, hence the suggestion that 'better' speakers require 'better' amplifiers.
At the other end of the scale large drivers are more sensitive than small ones and when used in reasonably large enclosures the bass extension is naturally quite deep. There is no need to 'throw' away midband sensitivity so the overall sensitivity remains high, crossovers can be simpler so the speakers are 'easy' to drive, so a few watts from a nice valve amplifier will do nicely.
Highly simplified of course but the principles are sound.