While browsing loudspeakerdatabase I noticed bass drivers have wildly different step response. At 60hz most long and medium throw drivers don't even remotely track the input signal.
The cheap Goldwood with only 2mm xmax does a lot better
The only driver I could find doing slightly better than the Goldwood is the insane 31.5" Fostex
If we disregard the practicality of it, would 4 Goldwood drivers sound better than one driver with 4x the xmax and 4x the price in the low bass region (30-120hz)?
How important is step response and which driver parameters are important for good step response?
The cheap Goldwood with only 2mm xmax does a lot better
The only driver I could find doing slightly better than the Goldwood is the insane 31.5" Fostex
If we disregard the practicality of it, would 4 Goldwood drivers sound better than one driver with 4x the xmax and 4x the price in the low bass region (30-120hz)?
How important is step response and which driver parameters are important for good step response?
They look like burst responses rather than step responses to me. Presumably the Fostex has the lowest cut-off frequency and therefore less phaseshift at 50 Hz than the others.
Cutoff doesn't seem to be the only factor.
Here is a driver with 4x the xmax of the Goldwood and the same fs
Here is the Goldwood
I don't really know how to relate this to real world bass quality.
I want make open baffle speakers that are 60cm wide and can be up to 250cm tall. So I have the option to have a crazy amount of woofer area. If low xmax sounds tighter/cleaner it may be worth it. But otherwise I could spend the same on higher xmax speakers and have a more manageable speaker size.
So don’t use tonebursts. Unless you know how to interpret the outcome. Something about Fourier analysis…
Exactly. A woofer, whether open-baffle or mounted in an enclosure, forms a mechanical highpass filter system. A highpass filter exhibits amplitude response and phase response, both of which vary with frequency. The tone burst responses shown are actually quite good.
See https://community.klipsch.com/index.php?/topic/172686-ht-2-12-subs-vs-1-15-sub/#comment-2555558 for a purely mathematical simulation using mathematically "perfect" filters.
What you're seeing here is nothing more than phase shift from the high pass nature of the woofer.
So if I EQ the B&C to the same frequency response curve as the Goldwood........
......the tone burst graph will also be the same?
So one is just a function of the other and tone burst doesn't give you anything that you cannot get from looking at a frequency and phase plot?
This is a FFT of a 5 cycle burst vs a continuous sine. Note that most of the burst energy is in harmonics and sub-harmonics, so if your device does not pass those frequencies, the burst will be severely distorted.
These answers go a little over my head.
I feel I ask something like "what is the distance from my house to your house" and and I get an answer involving the diameter of my car wheels and the pressure in my tires in stead of something like "100-110 km depending on the route".
I feel I ask something like "what is the distance from my house to your house" and and I get an answer involving the diameter of my car wheels and the pressure in my tires in stead of something like "100-110 km depending on the route".
Showing the speaker behaves just like a high pass filter demonstrates that what you see is based on the response and it can be reversed by modifying the response as needed.