I don't know any famous harpists or famous mediums
Accuracy in Loudspeakers---Define
- Thread starter Tom Brennan
- Start date
JoeESP9
ESL's & tubes since 83
"and what the result?" That's easy to answer. With one's eyes closed there is less distraction from the surroundings. You do realize you're preaching to the choir?
Blind people don't necessarily hear better. However, they do listen better.
JoeESP9
ESL's & tubes since 83
Big electrostatics can do 20Hz to 20KHz. They are a full range driver. We're not all using them because not everyone has the space or wants speakers that are seven or more feet tall and four feet wide. ESL's of that size are relatively expensive and like lots of power.
A conventional dynamic tweeter .3" in diameter will propogate 20KHz as an omnidirectional sources. It has to do with the size of the wave in relation to the size of the source.
Not when it's mounted on a baffle. But what's the point you're trying to make? In post #725 it was claimed that sound radiates in a spherical pattern (which it doesn't always) and therefore onmidirectional speakers are required for accuracy (which they aren't).
After 12 years and 738 posts are we any nearer to defining accuracy?
Yeah, it basically does, unless you're dealing with a large baffle with sharp edges. In that case the wave rolls across the baffle and diffracts off the corners like separate sources. The effect becomes more obvious as the size of the baffle increases.
Siedfried Linkwitz did a whole presentation on this jazz with charts and everything.
The point is that so long as the driver is smaller than the wave form it behaves like an omnidirectional point source. If the baffle is the problem, get rid of it. Isn't that what many modern speakers are going for? Reducing or eliminating the size or profile of the baffle?
As an aside, an omnidirectional radiating point source doesn't need to be a tiny little point. It only needs to mimic one, like MBL drivers do.
Yes, I'm aware of all that. But does is omnidirectionality a prerequisite for accuracy?
In my opinion, yes, to a point. I think it's useful for giving the sound a more natural balance of tone because controlled, undiffracted reflections come across as euphonic distortion that presents as a sense of space. I think that's where horns fall a bit short.
I would say, that more generally, uniform power balance (equal power at all frequencies in any specific direction) would be a prerequisite for accuracy.
Omnidirectionality can be a benefit, if the interaction of the speaker with the room is also controlled, so that the room acts like the original recording space, at least to a significant margin.
However- the biggest reason that omnidirectionality is sort of necessary in home speakers- is that the baffle size required to get truly constant limited dispersion at EVERY frequency- including the bass (i.e, to NOT have the bass go in every direction) is almost always impossibly large. Getting bass to NOT be omnidirectional is almost impossible, in practice. So, the best that can be done, is to make the rest of the spectrum match that. It's easier to make "ambient arrays" and such of tweeters and such in the rear of a speaker to make higher frequencies omnidirectional, than it is to make a subwoofer directional...
Regards,
Gordon.
Yes, in other words, non-coloured off-axis response. That makes sense to me.
That makes no sense whatsoever to me.
Yes, that's certainly one way to make the off-axis response flat, though there isn't really an axis anymore. I'm still not convinced that omnidirectionality is a prerequisite for accuracy though. It would appear that most of the rest of the world isn't either, or else we would see a lot more omnidirectional speakers.
One of the most compelling descriptions of what it is to have "accurate reproduction" of sound, that I've ever heard, is the proverbial "it puts you in the room with the performers".
That's pretty much impossible, if the listening room is severely aberrant in response compared to the original recording space.
This is where room tuning (traps, absorbing and/or diffracting mechanisms, and such) come in. The best loudspeaker in the world, isn't going to make a convincing illusion of the original space, if the room itself is disrupting the time and frequency response of the audio...
Regards,
Gordon.
I don't disagree. However, you said the complete opposite in post #743
That certainly implies to me that you're saying if the original recording was made in a large concert hall the playback should be a room with the same large concert hall acoustics.
A fairly loose definition that may not satisfy the OP.
They aren't meant to. They're meant to reproduce the recording, that's all.
That's not quite what I was getting after. I meant, that the listening room can't have tonal or time-based aberrations, that interfere with the way the spatial cues from the original recording would come through.
In a "bad room" with these sort of tonal and time-based anomalies, an omnidirectional loudspeaker is usually NOT an advantage at all- and actually, one with controlled dispersion may well be the better solution. But then- we're back to the original problem- how controlled is the dispersion at EVERY frequency? And how "involved" will the listener be, in terms of perceived soundstage, listening to such a speaker with non-uniform dispersion vs. frequency characteristics, due to the difference in tonal balance coming to them from different directions?
Regards,
Gordon.
bowtie427ss
Lunatic Member
See, i'm just the opposite.
I don't worry about such things because i know my ears are perfect, and nobody else can hear what i do.
