How much have drivers improved

Out of interest...

I'm using some relatively old scanspeak 8545 and 9500 drivers and I was wondering how much driver technology has moved on since these were first made. Assuming that everything in the build is properly implemented, do the latest drivers offer much improvement over these? I supposed I'm mainly interested in drivers of a comparable cost to these units.
 
Not a lot of improvement in the most recent years.

Case in point, improvements in drivers haven't been nearly so grand in the past 60 years as many would have you believe. Look at the JBL LE8T- an underhung, AlNiCo motor with a shorting path, and was in production WAY back when. Still sounds superb today.

Most cones still use paper, most motors still use the same old whatnot, and anchient field coil technology is having a resurgence. There have indeed been some improvements but they're not so common, nor dramatic, as most would have you believe. That said, some of the current motors are pretty slick, the TD motors, the Differential JBLs, some of the modern underhung neos from scan speak, tang band, and others.
 
Newer vs. Older

The most significant change in speaker design has nothing to do with improving sound quality; rather, it has to do with the increase of cobalt pricing that occurred years ago. The only difference between very old and relatively new drivers of equal quality, is the older ones will exhibit deterioration of suspension elasticity and a diminution of the magnetic field strength in the voice coil gap. An older, rebuilt driver, in many cases, is a superior buy, than that of a new one.
 
The older Scan-Speak drivers are still excellent drivers that sound very nice, IMHO. There have been advances that are beneficial to the overall quality of speaker drivers like XBL2 motors and Neo magnets to name a couple.

Has this resulted in earth shaking changes?

Not as far as I can tell, although drivers like the Exodus Audio "Audacity" midwoofer, designed by my buddy Kevin Haskins, has certainly raised the bar and has recently caught the interest of diy'ers.

Best Regards,
TerryO
 
The most important change have been is in the designing method of driver.
Now designers use computer to design drivers.
They use finite element analysis for motor design as well as cone design.
Few even design the chasis by this method.
To us, efficient motor design improves the weight & FEA design of cone makes cone better by improving breaking points.
 
The most important change have been is in the designing method of driver.
Now designers use computer to design drivers.
They use finite element analysis for motor design as well as cone design.
Few even design the chasis by this method.
To us, efficient motor design improves the weight & FEA design of cone makes cone better by improving breaking points.

Palesha,

The use of computers has certainly allowed designers to do the computation faster and can allow for modelling, but the programing is still done using mathematics that has been around for awhile. The Thiel Small parameters have contributed more to the understanding of driver performance than anything else.

I know several excellent driver designers, and while I'm sure that they can do the computations manually if necessary, they use computers for speeding up the process.

Just my 2 cents worth,
TerryO
 
Yes. surely mathematics is required for software.
But designer can simulate with endless opportunities.
The computer simulation have played very important part in FEA design of motors.
Similarly in the cone design.

I know one 3" driver designed for one chinese company by swedish designer.
He has developed one software for motor design. Also sells one more software for cone design.
The 3" driver quality made a chinese company big player in multimedia business.

so i think computer have played very significant role in modern driver design including XBL. Same can be said about driver testing. One German company have made state of art driver testing equipment. All is with computers.
All mechanical work reduced. But above all is human brain, which makes all this possible.
 
Yes. surely mathematics is required for software.
But designer can simulate with endless opportunities.
The computer simulation have played very important part in FEA design of motors.
Similarly in the cone design.

I know one 3" driver designed for one chinese company by swedish designer.
He has developed one software for motor design. Also sells one more software for cone design.
The 3" driver quality made a chinese company big player in multimedia business.

so i think computer have played very significant role in modern driver design including XBL. Same can be said about driver testing. One German company have made state of art driver testing equipment. All is with computers.
All mechanical work reduced. But above all is human brain, which makes all this possible.

palesha,

Computers are a handy tool and certainly increase productivity. Dan Wiggins who holds the patent on XBL2 is a friend of mine and I'll have to ask him sometime how he developed it. I do know that he wrote his own driver design software and in fact JBL offered to buy it from him. He declined, but has designed over a half dozen drivers for JBL, as well as other manufacturers and is also under contract with Microsoft.

Best Regards,
TerryO
 

rjb

Member
2004-06-08 8:58 am
Piha
E J Jordan in his 1963 book, covers the maths he used to design speakers, and in later Wireless World articles covered the development of his metal cone units. However talking to Doreen Bance, his wife at the time, the final refinement was always through listening tests.
I suspect the same is true for modern designers, despite the availability of computers, laser interference technology, etc, so the final arbitor is still the human ear, with all the baggage that goes with that. It finally comes back to opinion, (or in some cases what sells best).
 
E J Jordan in his 1963 book, covers the maths he used to design speakers, and in later Wireless World articles covered the development of his metal cone units. However talking to Doreen Bance, his wife at the time, the final refinement was always through listening tests.
I suspect the same is true for modern designers, despite the availability of computers, laser interference technology, etc, so the final arbitor is still the human ear, with all the baggage that goes with that. It finally comes back to opinion, (or in some cases what sells best).

The driver designers that I know personally certainly listen to prototypes built from their designs to check the sound and for any other issues before any production runs begin. This not only assures quality, but is also a prudent financial move!


Best Regards,
TerryO