Perfect Step Response

[ackcheng]

I wonder if anyone of you when designing speaker aiming to get a perfect step response.

Stereophile: Measuring Loudspeakers, Part Two

Sure a perfect step response means time coherent which is a good thing, but are the majority of the speakers out there has a lousy step response curve?

JA made this comment on Stereo web page "This is also my view. Of the 350 or so loudspeakers I have measured, there is no correlation between whether or not they are time-coherent and whether or not they are recommended by a Stereophile reviewer."

But of course, there are more than sound that put an equiptment on stereophile recommended list. And I do not fully trust these guys who has a conflict of interest anyway. but still, it is not difficult for a maufacturer to build a speaker with better step response, so why not?

[jackies]

Originally Posted by ackcheng

it is not difficult for a maufacturer to build a speaker with better step response

Where do you get this idea?
It is very difficult, and there are a couple manufacturers striving for that, dunlavy comes to mind...

[ackcheng]

I just thought that with all their resources and since they are running a business. It should be alot easier then DIYers!

[454Casull]

I don't want to see first-order electrical stuff running rampant, thanks.

[LineArray]

I also think, if you optimize a multiway for
perfect step response there will be a price to
pay.

Using 1st order crossovers may cause many
problems like

- tweeter distorsion
- wide crossover range
- woofers contributing to the direct sound while
driven far above their pistonic frequency range.
(resonances, lobing, beaming)

If one decides to make use of first order filters,
the whole design has to overcome those
restrictions.

Typically the quality of the drivers to be used
has to meet further criteria than with higher order
filters.

In my personal opinion the best crossover is not
the simplest possible one, but one that accounts
for the most important tasks of compensation,
also having a balanced energy frequency response
in mind.

Kind Regards

[aczern]

Transient Perfect loudspeakers



Dunlavy

Thiel

Manger

Vandersteen

Quad (ESL)

Spica

Meadowlark Audio

Earthworks

Duntech

Reference 3A

Role audio

MasterSource Audio

Grimm Audio

Myro

[LineArray]

Examples:

Stereophile: Quad ESL-989 electrostatic loudspeaker

Stereophile: Quad ESL-63 loudspeaker

http://www.stereophile.com/floorloud...en/index4.html


Manger:

When it comes to tweeters ... you will find cheaper
ones having very good transient response

[Vil]

Originally Posted by LineArray

I also think, if you optimize a multiway for
perfect step response there will be a price to
pay.

Using 1st order crossovers may cause many
problems like

- tweeter distorsion
- wide crossover range
- woofers contributing to the direct sound while
driven far above their pistonic frequency range.
(resonances, lobing, beaming)

If one decides to make use of first order filters,
the whole design has to overcome those
restrictions.

Typically the quality of the drivers to be used
has to meet further criteria than with higher order
filters.

In my personal opinion the best crossover is not
the simplest possible one, but one that accounts
for the most important tasks of compensation,
also having a balanced energy frequency response
in mind.

Kind Regards

Its possible to use FIR linear phase xovers up to 96dB/oct with digital delay on some drivers if needed. And it works very good ....