RE: Actually, I just want to reduce distortion

High Efficiency Speaker Asylum

Need speakers that can rock with just one watt? You found da place.

Posted by Paul Joppa (P) on August 7, 2012 at 18:18:15

In Reply to: Actually, I just want to reduce distortion posted by Frihed89 on August 7, 2012 at 14:27:26:

Bandwidth is also not the same as distortion.

We may have a communications issue, since so many terms have very narrow and precise technical meanings that do not match all that well with the broader meanings in non-technical talk. Rather that start a dictionary, I'll try to address the distortion issue:

The distortion you hear with large-scale music, on 90dB speakers, with a 2- or 3-watt amp, is most likely clipping - the amp cannot produce the instantaneous transient pressure peaks, Being a SET with no feedback, the clipping is "soft", which is to say it is gradual and does not produce the nasty sharp-sounding distortion of hard clipping, characteristic of solid state and (to a lesser degree) high-feedback tube amps.

To alleviate this problem, you must use speakers of greater efficiency, or an amp of greater (peak) power capability. As you noted, speakers of greater efficiency will reproduce any hum of other noises more efficiently as well. An amplifier of greater power output will solve the problem, but only if it does NOT produce more hum/noise.

The technical term here is "dynamic range" - the difference between the residual hum/noise and the maximum power before clipping. For example, consider a typical 2A3 amplifier with AC heated filaments and no feedback. It might produce 0.002 volts of hum; that's 0.0000005 watts into an 8 ohms speaker. The same amp will produce typically 3.5 watts at the onset of clipping. The ratio between those, expressed in dB, is 68.5dB. That's the dynamic range of the amp. With speakers at 90dB, it will produce 95.5dB of sound, and with no signal the hum will be about 27dB.

Now most audiophiles want a minimum of 102dB peaks, so if you are among them you'd need 96dB speakers. The hum level in your room with the same amp would then be 33dB. Whether you can hear that hum depends a lot on how quiet your listening room is.

This IS the high efficiency forum; be aware that many people here feel that an increase above the 102dB I mentioned above is well worthwhile.

Hope that helps.

This post is made possible by the generous support of people like you and our sponsors:

Follow Ups Full Thread

Topic - Increases in speaker bandwidth and sensitivity - Frihed89 10:09:56 08/07/12 (13)

RE: Increases in speaker bandwidth and sensitivity - Inmate51 08:15:40 08/10/12 (0)

RE: Increases in speaker bandwidth and sensitivity - claudej1@aol.com 18:34:33 08/09/12 (0)

Actually, I just want to reduce distortion - Frihed89 14:27:26 08/07/12 (3)

RE: Actually, I just want to reduce distortion - drlowmu 10:08:21 08/08/12 (0)

RE: Actually, I just want to reduce distortion - Paul Joppa 18:18:15 08/07/12 (1)

Thanks, it does - Frihed89 21:37:11 08/07/12 (0)

RE: Increases in speaker bandwidth and sensitivity - tomservo 13:19:53 08/07/12 (0)

RE: Increases in speaker bandwidth and sensitivity - Paul Joppa 13:13:45 08/07/12 (1)

RE: Increases in speaker bandwidth and sensitivity - Frihed89 14:18:48 08/07/12 (0)

RE: Increases in speaker bandwidth and sensitivity - djk 12:49:00 08/07/12 (3)

size? - Frihed89 14:17:18 08/07/12 (2)

Enclosure size - badman 15:02:25 08/07/12 (1)

Thanks, that helps a lot. - Frihed89 21:39:46 08/07/12 (0)

Follow Ups

RE: Actually, I just want to reduce distortion - Paul Joppa 18:18:15 08/07/12 (1)

Thanks, it does - Frihed89 21:37:11 08/07/12 (0)

Post a Message!