History and Types of Loudspeakers

[Sonus]

Good read

http://www.edisontechcenter.org/speakers.html

 

[flez007]

good read, thanks for posting it.

 

[j_j]

What's interesting is how the very first kind of loudspeaker invented (the electrodynamic speaker) is still, for most, the best available. Planars are for the most part electrodynamic with a different motor than a cone speaker. I'd have to say that in the useful (i.e. not budget or sonar) audio space, 99.9% of the rest are electrostatics.

I didn't mention piezo speakers for a reason. I don't do sonar, and I haven't met many audio piezo's that performed the way I'd prefer. Plasma, flame, and other speakers that make ozone aren't really interesting for reasons unrelated to how they sound.

There certainly seems to be some space for improvement in basic mechanisms, but I don't know what it is, either.

 

[GaryProtein]

. . . . I didn't mention piezo speakers for a reason. I don't do sonar, and I haven't met many audio piezo's that performed the way I'd prefer. . . .

I did discuss piezo speakers. You probably didn't scroll down all the way.

 

[j_j]

I did discuss piezo speakers. You probably didn't scroll down all the way.

I saw the discussion. You were similarly enthusiastic.

 

[GaryProtein]

I saw the discussion. You were similarly enthusiastic.

You're right!

 

[Groucho]

I was listening to some 40 year old speakers yesterday, and they weren't bad at all - I really don't think much progress has been made in speakers since they were made. Speakers are now much smaller for the same bass response (at the price of an unnaturally sharp roll-off perhaps) and maybe there are some advantages to narrow cabinets in terms of omnidirectionality (but not according to the Grimm people). The most exciting developments I would say are in DSP, and the possibilities for multi-channel audio, but these are relatively marginal compared to the inventive step of simply putting three dynamic drivers in a box - which c. 1973 gave us large speakers that sounded pretty reasonable. For flat panel enthusiasts we'd already had electrostatics for quite a while then, too, and they've not changed much in the meantime either.

 

[MylesBAstor]

I was listening to some 40 year old speakers yesterday, and they weren't bad at all - I really don't think much progress has been made in speakers since they were made. Speakers are now much smaller for the same bass response (at the price of an unnaturally sharp roll-off perhaps) and maybe there are some advantages to narrow cabinets in terms of omnidirectionality (but not according to the Grimm people). The most exciting developments I would say are in DSP, and the possibilities for multi-channel audio, but these are relatively marginal compared to the inventive step of simply putting three dynamic drivers in a box - which c. 1973 gave us large speakers that sounded pretty reasonable. For flat panel enthusiasts we'd already had electrostatics for quite a while then, too, and they've not changed much in the meantime either.

Is this the Daily Onion?

 

[Groucho]

Is this the Daily Onion?

Ho ho. So what do you see as the really fundamental changes that have rocked the world of stereo speakers? Aluminium baffles? More powerful magnets? Better cabinet bracing? More curves? Smaller, longer throw drivers? Coils of copper wire and capacitors now mounted on printed circuit boards? I see all of these things as minor tweaks around the periphery of a basic design that has hardly altered for decades.

Edit: come to think of it, virtually nothing has changed in the world of turntables, tape recorders and amplifiers either, so maybe it's no great surprise. Maybe they were all fundamentally 'right' 40 years ago, or it's too big a problem to take any further, or maybe there is great conservatism in hi fi. Probably a bit of all of the above.

 

[microstrip]

I was listening to some 40 year old speakers yesterday, and they weren't bad at all - I really don't think much progress has been made in speakers since they were made. Speakers are now much smaller for the same bass response (at the price of an unnaturally sharp roll-off perhaps) and maybe there are some advantages to narrow cabinets in terms of omnidirectionality (but not according to the Grimm people). The most exciting developments I would say are in DSP, and the possibilities for multi-channel audio, but these are relatively marginal compared to the inventive step of simply putting three dynamic drivers in a box - which c. 1973 gave us large speakers that sounded pretty reasonable. For flat panel enthusiasts we'd already had electrostatics for quite a while then, too, and they've not changed much in the meantime either.

Groucho,

Can you put a brand name and type in these 40 years old speakers?

Since you refer specifically to electrostatics, I have owned several pairs of SoundLab A2 electrostatics since the old internal wood frame structure till the current PX technology laser cut frames. Stator configuration, Mylar type and coatings, power distribution systems and crossover design evolutions have also contributed to a large change in sound quality along 30 years.

 

[microstrip]

Ho ho. So what do you see as the really fundamental changes that have rocked the world of stereo speakers? Aluminium baffles? More powerful magnets? Better cabinet bracing? More curves? Smaller, longer throw drivers? Coils of copper wire and capacitors now mounted on printed circuit boards? I see all of these things as minor tweaks around the periphery of a basic design that has hardly altered for decades. (...)

You are changing your first statement "much progress has been made in speakers since they were made" to "fundamental changes " . It would be really nice if you clarify what you want to debate.

 

[GaryProtein]

You are changing your first statement "much progress has been made in speakers since they were made" to "fundamental changes " . It would be really nice if you clarify what you want to debate.

OK, my flameproof suit it donned, then I'm out: As an outside observer, I think Groucho just used a different word, not copying and pasting word for word what he originally said.

Forgive me if that isn't the case. Carry on.

 

[Groucho]

You are changing your first statement "much progress has been made in speakers since they were made" to "fundamental changes " . It would be really nice if you clarify what you want to debate.

Is the idea, then, that we must only ever repeat the exact wording in our earlier posts, for fear of changing our statements? My reason for putting a slightly different slant (but not "fundamental" difference) on the question is that my earlier wording elicited mockery but no substance. If I repeat the exact wording I have no reason to think that I will receive a more constructive response. Maybe the respondent misunderstood what I meant, or maybe he understood it but decided to play to the gallery for laughs. Only by changing the wording can I expect to have a more reasoned debate. If you look at it, every thread with thousands of exchanges within it, relies on people reiterating their earlier positions with subtle changes in their wording in order to clarify what they mean, or to develop an argument more fully.

Edit: Thank you Gary!

 

[garylkoh]

Is this the Daily Onion?

I don't think that there has been much progress in fundamental acoustic theory since publication of The Theory of Sound by Baron John William Strutt Rayleigh. It's still a wave, requires a medium to travel through and there are still only three ways to reproduce it.

Baron Rayleigh wrote Volume 1 while sailing up the Nile with his wife. River cruises in the late 19th Century must be very different from cruises these days packed to the gills with food, wine, gambling, music and entertainment.

 

[mep]

Gary-There may not be much progress in "fundamental acoustic theory" as you say, but I think there certainly has been fundamental improvements in how loudspeakers from raw drivers to finished products are designed, built, and tested. I'm pretty sure that speaker designers 40 years ago didn't have the computer software available to them to model drivers, enclosures, and crossover networks that is available today. Nor did they have the advanced electronic test gear that is available to today's engineers and technicians. 40 years ago, the Thiele/Small parameters were just becoming known to people outside of Australia and started gaining widespread acceptance.

 

[garylkoh]

Mark, I was being facetious There was a comment that there have been no progress in loudspeaker design for 40 years.

One example of what computer modelling can do - the formulas for using a port to boost the output of a small loudspeaker is already well known. However, the same effect can be achieved electrically with the crossover network. I showed this at RMAF - a sealed box stand-mount loudspeaker that had prodigious bass. Needs careful modelling to ensure that the impedance doesn't drop to below 2 ohms at the tuning frequency.

 

[mep]

Gary-I'm well aware of the statement that was made about there being no progress in loudspeaker design for over 40 years. I'm becoming convinced that some people on this forum like to make outrageous statements just to start some controversy and/or a fight.

 

[MylesBAstor]

Gary-I'm well aware of the statement that was made about there being no progress in loudspeaker design for over 40 years. I'm becoming convinced that some people on this forum like to make outrageous statements just to start some controversy and/or a fight.

Well there's clearly been no progress in recording technology in the last 50 years!

And the same holds true in missile design too. They're still cylindrical, pointed, have flames shoot out the bottom (usually) and make a lot of noise.

 

[garylkoh]

Well there's clearly been no progress in recording technology in the last 50 years!

And the same holds true in missile design too. They're still cylindrical, pointed, have flames shoot out the bottom (usually) and make a lot of noise.

No progress in digital recording either - we are still using 0's and 1's. How come we haven't started using 2's yet?

 

[mep]

Well there's clearly been no progress in recording technology in the last 50 years!

And the same holds true in missile design too. They're still cylindrical, pointed, have flames shoot out the bottom (usually) and make a lot of noise.

As the Larry the Cable guy would say, "Now that's funny. I don't care who you are."