Do more sensitive drivers offer less distortion at "normal" listening levels? [message #17124] |
Mon, 25 October 2004 06:44 ![Go to next message Go to next message](/forum/theme/AudioRoundTable/images/down.png) |
akhilesh
Messages: 1275 Registered: May 2009
|
Illuminati (3rd Degree) |
|
|
HI Everyone, I was just wondering if more sensitive drivers offer less distortion at levels around 90-95 DB. For example, would a lowther, fostex type cone driver (rated at say 100 db for the sake of example) offer less distortion, since it is being fed less than a watt? ANother example, would a horn-based compression driver rated at 95 db, without the horn, offer less distortion? thanx -akhilesh
|
|
|
|
|
Re: Do more sensitive drivers offer less distortion at "normal" listening levels? [message #17127 is a reply to message #17124] |
Mon, 25 October 2004 12:40 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) ![Go to next message Go to next message](/forum/theme/AudioRoundTable/images/down.png) |
![](http://audioroundtable.com/forum/images/custom_avatars/5.gif) |
Wayne Parham
Messages: 18756 Registered: January 2001
|
Illuminati (33rd Degree) |
|
|
Most harmonic distortion from speakers comes from asymmetry in the motor. Generally speaking, the less movement that's required, the lower the distortion. So since high efficiency speakers in horns don't have to move as far for the same SPL, they generally offer lower harmonic distortion. There are other tradeoffs and things to consider, as is true of all things. For one, high-efficiency designs are generally reduced in bandwidth and sometimes response isn't as flat. If you optimize for efficiency, you generally de-optimize other parameters. Everything is a series of compromises. You want top speed? You might trade fuel economy. You want max output? You might lose some response at the extremes. The best solutions I've found are those that give me many of the advantages of horns while not sacrificing too much in response. My solutions all seem to be around 100dB/W/M in quarterspace or eighthspace, which is pretty high efficiency but not fully optimized in that direction.
|
|
|
|
|
|
|
Another perspective [message #17267 is a reply to message #17133] |
Thu, 23 December 2004 21:25 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) ![Go to next message Go to next message](/forum/theme/AudioRoundTable/images/down.png) |
Earl Geddes
Messages: 220 Registered: May 2009
|
Master |
|
|
After numerous studies of nonlinear distortion, in loudspeakers and otherwise, I have concluded that nonlinear distortion is not a primary factor in sound quality. This agrees with the work of Shawn Olive at Harman. What, IMO, does make a difference - directivity. Most High efficiency loudspeakers are more directional because they tend to be bigger. This directionality helps to minimize room refections and diffractions which are audibly very negative factors. But high directivity in and of itself is not enough, it must also be well controlled. Both the direct response and the power response have to be equal and this must be done with a high degree of directionality to achieve good imaging and presnce. but the room itself must also be done right or the loudspeaker won't make a whole lot of difference. No, I don't think that its the high efficiency of larger drivers and waveguieds that matter, but it is there inherent narrower directivity that is the primary factor.
|
|
|
Re: Another perspective [message #17269 is a reply to message #17267] |
Fri, 24 December 2004 11:58 ![Go to previous message Go to previous message](/forum/theme/AudioRoundTable/images/up.png) ![Go to next message Go to previous message](/forum/theme/AudioRoundTable/images/down.png) |
![](http://audioroundtable.com/forum/images/custom_avatars/5.gif) |
Wayne Parham
Messages: 18756 Registered: January 2001
|
Illuminati (33rd Degree) |
|
|
Hi Earl, Good to see you here, and thanks for your opinions. I agree with you about directivity. I like cornerhorn speakers with all flares set for 90o horizontal dispersion because then directivity is matched throughout the audio band, and wall reflections are minimized. With narrow vertical directivity, floor bounce is reduced too. A 40x90 flare works nicely with mids and tweeters placed at ear level. The pattern angle drop from a 40o flare is one foot for every 33 inches, so if the midhorn is placed three feet from the floor, the floor bounce is about 8.25 feet out, and not particularly problematic. That's my favorite implementation. As for distortion, I can really hear the difference between a driver with a shorting ring and another similar driver without one. It makes about 20dB reduction in second-order harmonics. But that's harmonic distortion that I'm hearing. What kinds of non-linear distortions are you talking about? Things like breakup modes or non-linearities in the motor movement? Wayne
|
|
|