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| Thread ID: 76731 | 2007-02-14 01:39:00 | buying an amp. | Fergie (6508) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 524582 | 2007-02-14 01:39:00 | hey all. i'm thinking about buying some floorstanding loudspeakers. a few i like are here: first, (www.trademe.co.nz), second (www.trademe.co.nz) or these (www.trademe.co.nz) first, thoughts on these? look ok for the price? anyway, i'm confused as hell as to what amp i should get, should the amp have a higher or lower RMS rating? and i see amps rated like 145w, but then its only 50w per channel. Take this one for example (www.trademe.co.nz) would this be good enough to power the above speakers? what should i be looking for in terms of specs for the amp to power those speakers. cheers |
Fergie (6508) | ||
| 524583 | 2007-02-14 02:12:00 | 1) The RMS power rating of the speakers need only be high enough to cope with the amp you use. 2) Unless you are (i) deaf, (ii) a real headbanger who wants to go deaf, or (iii) live in the country far from human habitation and want to listen to your favouite music while down on the 'back 40', you will find that any of those speakers will drive you out of the house at 25W RMS input, let alone 50 watts. The average listener who wants to stay on good terms with the neighbours will not use more that 5-15 watts of amp power-out during normal listening, and maybe up to 25W for your favourite songs. Buy whichever of the three speakers you like best, your amp can be anything from 25W RMS per channel up to 100W and you will still be smiling. Those into heavy metal, head banging, listening to music while stoned, or drunk, or both, will find 100W RMS totally inadequate. If playing Abba or Barry Manilow it is not nice to use more than 1W per channel, and the speakers should be laid face down on pillows. The amp pictured will be more than adequate unless you are an audiophile or hate the neighbours, and you can choose your speakers on price/appearance. The pictured speakers are all adequate, though personally I'd go for the Sapphires Cheers Billy 8-{) |
Billy T (70) | ||
| 524584 | 2007-02-14 03:07:00 | Is the impedance of the speakers any issue? I notice some of the speakers are rated at 6 ohms, whilst others are 8 ohms. Do they have to match with the rated impedance output of the amp or anything like that? | roddy_boy (4115) | ||
| 524585 | 2007-02-14 05:01:00 | The speaker impedance is less of a consideration now than it was with valve amplifiers. They had output transformers and if the load was wrong the valves were not running correctly, and this could cause extreme distortion (among other things). Transistor (or MOSfet) outputs have very low impedance, and the load impedance matters only to the extent that at a given output voltage, lower impedance speakers will draw more current (thus power). Taken to extremes, you could exceed the amplifier's rating at maximum output. But you will probably have blown the speakers first. :D At sensible volumes, the ampolifier won't notice the difference between "6 ohm" and "8 ohm" speakers. At some frequencies they will have the same impedance, anyway -- the impedance is frequency dependent. |
Graham L (2) | ||
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