I have to build the box to make it manageable to ride. That thing above is a nightmare and too heavy.
https://www.parts-express.com/Dayto...ngRngrA7WECPRtPAcbjQBtcfDm1rurUxoCTlwQAvD_BwE
This is what I've used in the past. Maybe thats where I need to head again. With one of these...
https://www.parts-express.com/Dayto...u0ynGBfwJvm-4ui2fTuHtyucbpq6IVQxoCfjUQAvD_BwE
This is what I've used in the past. Maybe thats where I need to head again. With one of these...
https://www.parts-express.com/Dayto...u0ynGBfwJvm-4ui2fTuHtyucbpq6IVQxoCfjUQAvD_BwE
Thats what I'm doing. But I need thoughts on the speaker. maybe my guess of a 15 was too big. maybe a 10 is more in line with 3.5 CF.
Certainly 10" or less.
Maybe planet10 has something designed that would fit.
https://www.diyaudio.com/community/members/planet10.346/
Maybe planet10 has something designed that would fit.
https://www.diyaudio.com/community/members/planet10.346/
Define 'loud' and how low are you willing to 'sacrifice' as my 'knee jerk' response to your wants/needs is multiple 8" horn drivers, so not particularly light at ~8.46 lbs/ea., but the price one pays for high SPL.
At a glance, (4) side/50 L sealed won't make a lot bass, but ~40 Hz hi-passed - up BW peak SPL will basically be limited by how much power is available up to the driver's 240 W/ea..
At a glance, (4) side/50 L sealed won't make a lot bass, but ~40 Hz hi-passed - up BW peak SPL will basically be limited by how much power is available up to the driver's 240 W/ea..
I could live with a 40 bi-pass.... but that weight is perhaps too much. Also, check out that dayton 24v amp I linked above. I doubt I'd get anywhere near the max of those drivers you linked. A much lighter built 8" might be better to make an array.
I made a very successful trailer with that DVC dayton 10" I linked... two of them, with a four channel dayton 24v amp.
Didn't click on any links, just a quick response to a loud portable bike (sub) woofer. That said, its 50 W/side sims >115 dB/m/4pi from 40 Hz-up, peaking at >125 dB/70 Hz-up.
I've been playing with speakers on bikes for a few years now, and settled on a "brute force" approach:
https://instagram.com/batteryacidsoundsystem
That said, after crashing the bike and breaking my leg in a pretty bad way, I'll happily be a loser with a trailer because I'll be able to transport a bigger rig in a safer manner.
My suggested approach is balance of compromises that suit me:
10" or 12" lightweight low/mid (not a pure subwoofer driver) in a compact ported box tuned to 50~60Hz, with DSP for EQ, high & low pass and powered by either class D car amp on 12V LiFePo4 or a 36V chip amp on Li-ion (ie repurpose an e-bike battery).
Whilst the latter solution is more effective on paper, its also involves a lot more stuffing about with a steeper learning curve.
If you're just looking for bass on a regular (not cargo) bike then maybe drop down to a pair of 8" woofers each side in as large a box you can handle hanging off the bike.
My next system is planned to be a 100AH Renogy 12.8V battery powering a Pioneer GM-D9500F for mid/top and GM-D8500M for 4 or 8x 12" bass boxes... on a trailer!
Bass boxes aren't quite "subs", they'll be Eminence Delta 12LFA in 80L boxes tuned to 50hz made from 12mm ply. Those drivers arent special but I already own them, would suggest neo magnets if you're buying new. Going for bigger boxes than current because... trailer!
Wouldn't think about horn speakers for bass on a bike, and IMO any supposed inefficiencies with the above approach to amp and speaker design can easily be made up for with an extra few kilograms of battery (nevermind the cost though).
There are so many compromises that it's about what suits you - cost / complexity / reliability / output / weight / size / looks etc... and you might take a few attempts to find the right compromise.
https://instagram.com/batteryacidsoundsystem
That said, after crashing the bike and breaking my leg in a pretty bad way, I'll happily be a loser with a trailer because I'll be able to transport a bigger rig in a safer manner.
My suggested approach is balance of compromises that suit me:
10" or 12" lightweight low/mid (not a pure subwoofer driver) in a compact ported box tuned to 50~60Hz, with DSP for EQ, high & low pass and powered by either class D car amp on 12V LiFePo4 or a 36V chip amp on Li-ion (ie repurpose an e-bike battery).
Whilst the latter solution is more effective on paper, its also involves a lot more stuffing about with a steeper learning curve.
If you're just looking for bass on a regular (not cargo) bike then maybe drop down to a pair of 8" woofers each side in as large a box you can handle hanging off the bike.
My next system is planned to be a 100AH Renogy 12.8V battery powering a Pioneer GM-D9500F for mid/top and GM-D8500M for 4 or 8x 12" bass boxes... on a trailer!
Bass boxes aren't quite "subs", they'll be Eminence Delta 12LFA in 80L boxes tuned to 50hz made from 12mm ply. Those drivers arent special but I already own them, would suggest neo magnets if you're buying new. Going for bigger boxes than current because... trailer!
Wouldn't think about horn speakers for bass on a bike, and IMO any supposed inefficiencies with the above approach to amp and speaker design can easily be made up for with an extra few kilograms of battery (nevermind the cost though).
There are so many compromises that it's about what suits you - cost / complexity / reliability / output / weight / size / looks etc... and you might take a few attempts to find the right compromise.
For your application, these look interesting to me:
12", 93 dB sensitivity, 71 Hz f3 in 1.2 cubic ft sealed, 41 Hz F3 in 2.8 cubic ft ported (this can likely be fudged for a smaller box with decent bass still - if you're interested I'll run the numbers)
https://www.parts-express.com/GRS-12PT-8-12-Paper-Cone-Prosound-Woofer-3-Voice-Coil-8-Ohm-292-806
12", 97 dB sensitivity, 73 Hz f3 in 2.4 cubic ft sealed, ported is impractically large
https://www.parts-express.com/Goldwood-GW-1258-12-Pro-Woofer-290-382
You could use 2 of them in parallel to bring the impedance down to 4 ohms, which is where most of the smaller DC-supplied amplifier modules put out the most power. And if you used the GRS sealed, you could do 4 woofers total if you want to use a stereo amplifier, and still come in around your previously stated total volume target.
If you provide more info about your previous setup with the 10" dual voice coil woofers (box size, coil configuration/power being delivered to it, etc.) we can estimate the differences between them.
12", 93 dB sensitivity, 71 Hz f3 in 1.2 cubic ft sealed, 41 Hz F3 in 2.8 cubic ft ported (this can likely be fudged for a smaller box with decent bass still - if you're interested I'll run the numbers)
https://www.parts-express.com/GRS-12PT-8-12-Paper-Cone-Prosound-Woofer-3-Voice-Coil-8-Ohm-292-806
12", 97 dB sensitivity, 73 Hz f3 in 2.4 cubic ft sealed, ported is impractically large
https://www.parts-express.com/Goldwood-GW-1258-12-Pro-Woofer-290-382
You could use 2 of them in parallel to bring the impedance down to 4 ohms, which is where most of the smaller DC-supplied amplifier modules put out the most power. And if you used the GRS sealed, you could do 4 woofers total if you want to use a stereo amplifier, and still come in around your previously stated total volume target.
If you provide more info about your previous setup with the 10" dual voice coil woofers (box size, coil configuration/power being delivered to it, etc.) we can estimate the differences between them.
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The two I suggested above were influenced by price. Obviously neodymium woofers will be lighter (about 50%), but they're typically significantly more expensive also (2-3x or more).
Using four B&C10CL51, a pair in each 60 liter box (Fb 60Hz), you could expect close to 130 dB at one meter down to 60Hz.
Using softwood 1/2" plywood, each box could weigh under 20 lbs with the 2.6 pound woofers, 35 pounds for the pair total would be possible, even including some bracing.
That said, the chip amp you have been using can't swing 37 volts output, so won't reach that level.
Bitsmasher's advice in #31 all makes sense, though with a trailer I'd be inclined to use the SS15 tapped horn for the +6dB output gain it has over bass reflex designs, 1/4 the battery power used is a good deal.
Art
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You guys, This is excellent! Let me look these over and think on it. In the meantime, can we talk a bit about these amps? I've been salvaging very high quality panasonic 18650 cells and I have a few of these dayton 18650 holders that integrate well with compatible boards , but the highest voltage they do is a five battery 21 volt holder. I like to charge the cells separately... so no charging feature is needed. I guess my dream is to end up at a 4 ohm system and at a higher voltage... (at least 24v) I own a bunch of three cell 18650 holders... but many of these boards have a cutoff at 24v, and if I used two of these holders, I'd be at 25v.
Also, I'm willing to swap batteries mid evening.
Thoughts?
Also, I'm willing to swap batteries mid evening.
Thoughts?
You can use a step-up or step-down converter (DC-DC), I'm using this https://www.soundimports.eu/nl/sure-electronics-aa-ab32191.html with 10S
As for a bike solution, you could do something like this (without the top):
As for a bike solution, you could do something like this (without the top):
What are the drawbacks to using a dc to dc step up converter, say, from 12 to 36v?
It does not increase the power.
For example, 12V @ 5A would become 36V @ 1.6A.
And that does not include the power losses that will occur in the conversion.
For example, 12V @ 5A would become 36V @ 1.6A.
And that does not include the power losses that will occur in the conversion.
its basically what any off the shelf car audio amplifier already has built in.
they are designed for 12 to 14 volts, and boost converter for voltage
for efficiency you could use a typical class D audio amplifier.
tradeoff is it will pull more current since its 12 volts being stepped up.
12 volts means less series cells, so more cells can be parallel for current capacity.
but your using more current anyways.
or 24 volts is more series cells, so less current reserve since you need more cells
for voltage
the design approach is correct, use a pro audio type woofer for
more efficiency. and even with 20 to 50 watts
a pro woofer is much louder than a hifi woofer.
tradeoff is a pro audio woofer trades bandwidth for efficiency
it wont go super low like a sub.
your basically looking at any typical 8" or 10" pro audio driver.
8" woofer needs about .6 to 1 cubic feet
10" woofer around .8 to 1.3 cubic feet
no need to high tune, its annoying and will unload quicker.
just tune to the Fs of the driver or about 3 to 5hz higher.
Could just look at 10" pro audio drivers for bass guitar.
The Fs will be lower than a PA mid bass.
Basically needs a 1 cubic to 1.3 cubic box and tune the port
to Fs of the driver
they are designed for 12 to 14 volts, and boost converter for voltage
for efficiency you could use a typical class D audio amplifier.
tradeoff is it will pull more current since its 12 volts being stepped up.
12 volts means less series cells, so more cells can be parallel for current capacity.
but your using more current anyways.
or 24 volts is more series cells, so less current reserve since you need more cells
for voltage
the design approach is correct, use a pro audio type woofer for
more efficiency. and even with 20 to 50 watts
a pro woofer is much louder than a hifi woofer.
tradeoff is a pro audio woofer trades bandwidth for efficiency
it wont go super low like a sub.
your basically looking at any typical 8" or 10" pro audio driver.
8" woofer needs about .6 to 1 cubic feet
10" woofer around .8 to 1.3 cubic feet
no need to high tune, its annoying and will unload quicker.
just tune to the Fs of the driver or about 3 to 5hz higher.
Could just look at 10" pro audio drivers for bass guitar.
The Fs will be lower than a PA mid bass.
Basically needs a 1 cubic to 1.3 cubic box and tune the port
to Fs of the driver
Outdoor low end at any kind of volume does not happen with 10" drivers, or with low power. You need to move a lot of air, and this takes large cone area and a fair bit of power. How many riders do you expect to hear the bass from your speaker?