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You're funny.

I'm not even slightly interested in who you are. I'm only interested in ideas.

You're wrong. In the case of a bass reflex speaker we are not merely cascading responses, we are adding them - we hear the speaker driver and the output of the port. Intuitively, we can't correct the sum of the two (make it into a single transient impulse) because the port 'echoes' whatever we...

I never mentioned linearity - it's basically linear. Are you claiming that the driver chained with a resonator - that has to go through a delayed undershoot before it becomes in-phase - is minimum phase?

But if ported had never been invented, you wouldn't even worry about it. Audiophile budgets are usually in the thousands of dollars, often tens of thousands. Speaker drivers start in the tens of dollars and might stretch to hundreds. MDF comes in huge sheets for $40. I don't see why it's...

What does that mean? An audio system can certainly be designed to give no phase modification (it might need to add some latency, however). It will, always be true, of course, that a 1mm length of cable is causing some phase shift. Just not very much. So your statement is literally true, but not...

Gradually homing in on this. I present to you three statements: 1. Linkwitz says: "Vented bass speakers are resonant structures and store energy which is released over time. For accuracy, bass must be reproduced from sealed or open baffle speakers that are non-resonant." 2. Some maths forum...

I wonder if the nature of music is helping us here. Chords played higher up on the piano keyboard sound fine, but at the bottom end sound terrible. Any keyboard improviser or composer knows to start making their chords 'sparse' as they go lower. The theory seems to be that our hearing is less...

Yes, it's incredible how this could ever be an issue - it's such an obvious refinement that any designer should include in their products. I can only think that many are not really product designers at all, but mere data sheet implementers and/or ideological zealots who think that such...

KEF say that the ideal shape is a hemisphere that expands and contracts, and that their tangerine waveguide converts a conventional moving hemisphere into something that approximates the expanding one. I think.

Let me try to be more precise. The generalised way to correct a system's foibles is to invert its impulse response, so that if you feed an impulse in, you get the same impulse out (but amplified or converted into sound pressure, or whatever). A latency delay may be necessary to achieve this. I...

I don't think you're quite following the argument..! No one tries to correct a BR speaker in the time domain. If its frequency response shows loads of bass then it's a result!

The speaker itself is perfectly stable. I'm talking about using DSP to get to a time domain duplicate (not a frequency domain approximation) of the signal. It is the overall system that would be unstable.

To make the output a duplicate of the signal - even in the time domain.

In simple terms, consider, what we would need to do to eliminate a room reflection at the listener's ear. We would send out an impulse from the speaker, and it would be picked up by the ear, followed by a delayed reflection of the impulse. We could eliminate the reflection by sending out an...

But I can invert a transfer function only if the result is stable. With a ported speaker the delayed output of the resonator is higher than the output of the cone driving it so it would not be stable.

There are several aspects in play, it seems to me. - In frequency response terms, a ported system can behave absolutely perfectly when fed a steady sine wave. This is not an issue. - There are, however, phase shifts that are associated with the port, that vary with frequency in a characteristic...

Two very obvious things: 1. The old woofers were usually sealed 2. The baffles were wider, placing the baffle step at a lower frequency - a fundamental difference that cannot be eliminated with EQ. I recently had some pretty large three-way Goodmans speakers from the 70s and they were really...

You would have thought that a tone with a strong second harmonic would be a reason to hear them as the same note? (if I am following the argument) If an iphone does the missing fundamental trick with its tiny speaker, does it not work for them?

The "I know but can't be bothered to say it, so look it up" ploy is so cliched, discredited, pathetic. If you know what you're talking about, then say it. If you don't, then don't. (I'm not quite as nice a person as @oivavoi :))