I guess my confusion is that I use the terms as interchangeable when they technically aren't..
Pls take my example of the same driver in a sealed box tuned via Linkwitz transform, to match the response of the driver in a necessarily larger BR box tuned to 31Hz.
I know the sealed box will put out less SPL at 2.83v, than will the BR, using the same passband pink, that has the full bandwidth of intended operation
(for this example, 31 to 100Hz).
And I know the sealed will require much more power to reach the same SPL.
Like said before, this is easily measurable..
What am I missing or misinterpreting about what you're saying?
As I don't begin to understand how you can say sensitivity depends only on BL and mass & area of cone...
In my blind test, i can locate the source precisely with sine waves and is meaningless.
It was just a gain of time because i can do it with music but it is a lot more time consuming and i don't want too loose too much time for a problem than annoy me each time i listen my loudspeakers and therfore is already identified.
Hide-and-seek is a funny game, if i always win with subs it is because i'm lucky that's all
If you don't follow your last sentence then you are missing my point, which is that what you claim as "I know" cannot possibly be true. Hence something that you have convinced yourself is true, isn't. It's simply physics, but if you don't understand that then you can't follow my proof.
'I know' because I have made numerous measurements of different boxes using the same driver tuned to the same response.
Measurements using the technique I described.
Are you saying a box doesn't matter for efficiency/sensitivity?
That's what it sound like to me???
Above resonance, the "box" doesn't make any difference, only near resonance and below does the box enter into the equation. (Some form of baffle is assumed here as an open baffle is certainly less efficient, but even then at some HF, even an open baffles efficiency must match that of a baffled driver.)
You need to read up on loudspeakers as you have some misconceptions about how they work. And if your measurements show differences then you are measuring something different than what you think you are.
You need to read up on loudspeakers as you have some misconceptions about how they work. And if your measurements show differences then you are measuring something different than what you think you are.
I'm sure I need to read up more..self proclaimed dummy
But that resonance, the BR port, adds a heck of a lot of efficiency vs the power boost it takes to get a sealed box to the same f3, does it not?
Please realize the measurements I described don't go by the industry's method to define sensitivity.... you know, pick a certain level of SPL on the response curve, and tie it to nominal impedance and voltage used . That commonly used spec is sad at best imo.
What I laid out measures the the average sensitivity for a signal evenly spread across the entire passband.
Again, if I want the same SPL from a sealed box and a BR, where the transfer functions have been made identical for both boxes, I will need to apply more voltage, more power to the sealed. This is using pink.
Seems like simple physics.
What am I missing?
I went to your web site through your signature and saw you were interested in stained glass. You should add a link to your stained glass work to your signature, too. After I learn to DIY my speakers I want to DIY stained glass to add ambiance to the home theater.
Hi Mitch, only the first part was for Earl - and I have noticed your informed posts on similar issues so I am pleased to have your comments.
The DSP solution was what I had planned to deal with the horn driver offset, more or less the standard solution these days.
But the system is for home theatre (so quite a lot of channels), music, even some vinyl still.
It would be nice to encapsulate the offset solution within the speakers and have a nice flexible solution that doesn't depend on software.
I am so tired of stuff that ceases to work after the latest OS update, or new computer, or the company orphans the product, or some weird interaction with the BIOS happens, or copy protection in software messes up, or a new connector standard renders all the hardware obsolete, or ... I am sure you know what I mean.
It does occur to me to aim for an acceptably flat amplitude response and have phase correction in the software as an additional "perfectionist" layer.
Like the removal of the all-pass phase of the LinkwitzRiley for example, I haven't looked into this much yet.
Best wishes
David
Following the discussion about closed box versus bassreflex, I found this whitepaper, boldly titled: Why Bassreflex is not Suitable for a Subwoofer.
The author is a Professor in Mechatronics and member of the team behind this loudspeaker:
The author is a Professor in Mechatronics and member of the team behind this loudspeaker:
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Yes, I meant it in this sense too.
Yes, I am aware of the natural delay of the woofer.
But in, say, a LinkwitzRiley crossover the natural delay of the woofer is already accounted for to maintain the correct phase relation if the drivers are in the same plane.
So to allow for a driver set back from the baffle we need a different crossover to do it "correctly".
And I don't know a systematic analysis to cover this situation, comparable to Linkwitz's analysis of the no offset case.
I hoped someone would already have worked this out for me.
Best wishes
David
David, check out this thread "Quasi-optimal" crossover for high-efficiency loudspeaker system