Mid and tweeter are largely irrelevant as 80% of the energy in a typical music program goes to the woofer. A sealed box is pointless. It's probably better if I phrase my question a different way. I can get a higher SPL by recreating a 'boombox' sound. How high can tune the port before it just sounds ridiculous.
What (size) woofer are you using?
Is the size restricted?
What about a low tuning with active eqalizer?
Closed box with linkwitz transform?
Why is a closed box pointless, by the way?
Is the size restricted?
What about a low tuning with active eqalizer?
Closed box with linkwitz transform?
Why is a closed box pointless, by the way?
Depends in the crossover frequency and music program!
Tune it up to 200 Hz, if you want, but it’s only going to give you up to +6 dB over a narrower and narrower range of frequency. Beyond that getting more SPL needs more box (and/or driver) or more watts. 100 or more watts is practical off 14.4V, but doing so gets out of “spare parts” territory and into “go buy something (or parts to build) for this”.
Sometimes a speaker is what it is.
high tuning unloads faster.
Driver with more efficiency
is a feasible cure for low power.
Slightly more cone area would help if
possibly.
Is the sub separate, or integrated in one unit.
If high tuning is considered a solution
then a high tuned 6th order bandpass might
work. The extra needed volume could be
just used for a 6.5"
Since quality and possible bass output
more realistic with modern 6.5"
What driver is shown in sim?
Is the system meant to be carried around
or just permanent install
this case and question
I would just use BB4 alignment/volume
and raise 7 to 12 Hz from there.
Only a guess not knowing driver
high tuning unloads faster.
Driver with more efficiency
is a feasible cure for low power.
Slightly more cone area would help if
possibly.
Is the sub separate, or integrated in one unit.
If high tuning is considered a solution
then a high tuned 6th order bandpass might
work. The extra needed volume could be
just used for a 6.5"
Since quality and possible bass output
more realistic with modern 6.5"
What driver is shown in sim?
Is the system meant to be carried around
or just permanent install
this case and question
I would just use BB4 alignment/volume
and raise 7 to 12 Hz from there.
Only a guess not knowing driver
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Okay, so I got it done. Many usefull tips. I used a ridiculously large (80mm) port tuned to 70Hz. I'll post a pic as soon as I get it painted. It's my fault but I don't think many understood what I was trying to achieve.
The 'throw more power at' is a popular yet medieval solution to way too many problems. Yes, I can get 100 watts out 14.4V but what good is a portable with an 8 minute battery life.
I'm surprised you can find any 14.4V battery that'll be run down in 8 minutes of 100w-peak music playback.
Chris
The point I was too-subtly making is this: music typically has a 10dB peak-to-average ratio, so your 100w peaks will be around 10w average. Since batteries are drained by average power, you'll probably find that your battery will last a lot longer than you might expect.
Chris
Chris
I am haunted by memories of my youth. My Hitachi boom-box required TWELVE DURACELLS! Two weeks allowance gone in a couple of hours.
Thanks all. It was a worthwhile exercise. The results did not meet my expectations but it's good enough for the garden. Part of the reason for the initial disappointment is that I used a DVD / Home Theatre for testing. (My amp board hasn't arrived yet).
The exercise offered insight into the way manufacturers do things, and why. My results were inevitable when I tested using regular bookshelf speakers as satellites. Even a small pair of bookshelves provide several more dBs that the pathetic satellites that come with big box home theatre systems. The bookshelves were drowning out the sub.
Another trick they use to compensate for inadequate subwoofers is to lower the resistance. Generally these subs are rated @ 3ohms (some of Sony's are 1.5) to give the sub a little more oomph to keep up with the satellites. My 4ohm sub was always going to be slightly handicapped.
It ain't pretty but it's done and fits under the patio sofa.
Thanks.
The exercise offered insight into the way manufacturers do things, and why. My results were inevitable when I tested using regular bookshelf speakers as satellites. Even a small pair of bookshelves provide several more dBs that the pathetic satellites that come with big box home theatre systems. The bookshelves were drowning out the sub.
Another trick they use to compensate for inadequate subwoofers is to lower the resistance. Generally these subs are rated @ 3ohms (some of Sony's are 1.5) to give the sub a little more oomph to keep up with the satellites. My 4ohm sub was always going to be slightly handicapped.
It ain't pretty but it's done and fits under the patio sofa.
Thanks.