i'm looking to build a bicycle trailer system with a pair of proel flash8 96dB 8" two ways to start, then add a pair of high efficiency 12s in a sealed car box and eventually another pair of 12s. i plan on using a pair of 12v 7a batteries in series for a 24v 7a system crossed over at 70Hz with inline passive crossovers using sure electronics modules. what i'm wondering about is the best way to wire/amp the subs for efficiency & without stressing the amps. my first impulse was to use a pair of 2x100w modules (originally i planned on biamping to a pair of larger air motion tweeters, but i scored the proels for just $100, and i can roll immediately with them). right now, i'm thinking of getting a more cost effective 4x100w module, but worry that would put more strain on the amp, & think 2x100w mains and 1x200w sub is the way to go. running the subs in stereo would be a waste of power, wouldn't it as per the +3dB rule of "free power" when doubling speakers on a single amp channel. right? finally, wouldn't it be best to load the subs at 8 ohms for an easier load on the amp? sure amps put more power out at 4 ohms, but especially pushing the amps to max power, wouldn't 8 ohms better protect the amp(s)? the woofers i'm looking at are 8 ohms, so they'd be 4 ohms as a pair to start. the 4 ohm versions roll off about 10Hz higher and are slightly less efficient. basically, i'm asking if 2x100 @ 8 ohms + 1x200 @ 8 ohms is the optimum way to go, especially using smaller batteries. my basic understanding of loads and efficiency tell me that's the way to go. many thanks in advance for a more tech saavy evaluation of my plan
i don't actually have it yet, but i decided on a $150 schwinn trailer i saw at walmart for two reasons... 1st, it's 29" wide between tires making it possible to fit a pair of 14" wide sub boxes between them and 2nd, because it uses real wheels with spokes, so i'll be able to run higher tire pressures. i used to have an instep bicycle trailer i intended to build a system on, but it had plastic rims which didn't have lips to secure the tires. i aired them up at 60-80psi, and within a day of each other, they blew their innertubes with gun loud pops. i want to be able to run at least 80 psi tires to make hauling a heavy load all day easier. another thing i like about the schinn vs the instep is that it doesn't have raised tabs for mounting the "roll bars" to so i can mount a flatbed flush to the frame instead of mounting it on 1 1/2" risers for both a lower center of gravity, and a nicer look. i didn't get serious about attempting another trailer system until i took a yardstick to the schwinn and looked sub boxes up to see if i could fit a pair of 12" boxes. most trailers can't. my first attempt at a trailer system was sad... i collected everything i needed for a 12v system including a pair of really cool power acoustic amps that had big blue round plasma (borg) lights that flashed to the beat and made different patterns for different songs. it was going to use a downward pointing 10" sealed sub and 4 NHT superzeros, 1 at each corner, but i discovered too late, once i started building the frame, that i couldn't get it out my 2nd story door because it crashed into the guard rail. now i'm on the ground floor, and even if i wasn't, a flatbed system is much lighter than a heavy 2x4 framed system and will be easier to break apart. all i have to do now, is collect everything i need. i already have my mains issue solved.
Maybe work on your text delivery to entice people to engage with you.
Spelling, grammar, formatting, thought flow etc it loks like a thought gallop.
Secondly I can see that you have read a bit, but it still needs to coalesce in a practical way, I mean there is theory and what works for you in practice, only you can work that out for yourself.
EG: you may discover that you neither want or need 100W of anything on a bicycle.
Spelling, grammar, formatting, thought flow etc it loks like a thought gallop.
Secondly I can see that you have read a bit, but it still needs to coalesce in a practical way, I mean there is theory and what works for you in practice, only you can work that out for yourself.
EG: you may discover that you neither want or need 100W of anything on a bicycle.
If going for 8R final impedance per channel, i'd suggest a higher voltage to have enough "drive" for the chassis. 36V (or 3xSLA) would be nice then.
For example, i have one 4R 12" bass on one channel and 2x 8R+Tweeter and 6/12dB x-over in parallel on the other channel, running the amp at 36V with ease. Total system power is 2x175W at 4R and 36V.
For example, i have one 4R 12" bass on one channel and 2x 8R+Tweeter and 6/12dB x-over in parallel on the other channel, running the amp at 36V with ease. Total system power is 2x175W at 4R and 36V.
well, i was planning to start with 2 x 12v 7a batteries with just the mains, and then adding a second pair of 12v batteries down the road on a separate circuit for the bass. do you think a 36v 7a setup would be enough to run the entire system for say 8 hours? most of what i intend to do is lower volume cruising, but would like the option to max things out if crowds decide they want to dance. so you're saying everything i've planned is good except you'd add a 3rd battery to go to 36v, correct?
https://www.youtube.com/watch?v=hQW4LpiDisM
let the haters hate
a lot of people used to get jazzed up over this system including the hot double D MILF that freaked on my leg
i am fighting back against nearly 30 years worth of lousy music you can't dance to since REAL hip-hop was offed and have had it listening to souless techno, gangsta crap and spitters in general. no funk... no positive... it has to be stopped! i want to dance again. this is the ONLY WAY
oh i DEFINITELY want 100w+. i've already done the sonic impact thing with a bike system, and couldn't even hear it rolling in front of a night club. this system is intended for parties, if i can get people motivated. not just that, but i want a system that can embarrass car systems bikes are cooler than cars style. this system is intended to be lady bait and a demo of what higher quality sound is. a lot of locals here like to blast their annoying hillbilly music on cheap, lousy sounding, toy PA speakers with lighting effects. i'm trying to do the exact opposite of the status quo here in every way. no car, no lousy sounding toy speakers, no port boom, no hillbilly music, no gangsta crap, and better sound than i've heard out of most bike systems with crappy auto coaxes. i want to do woofer cooker with a bike.
https://www.youtube.com/watch?v=hQW4LpiDisM
let the haters hate
a lot of people used to get jazzed up over this system including the hot double D MILF that freaked on my leg
An externally hosted image should be here but it was not working when we last tested it.
i am fighting back against nearly 30 years worth of lousy music you can't dance to since REAL hip-hop was offed and have had it listening to souless techno, gangsta crap and spitters in general. no funk... no positive... it has to be stopped! i want to dance again. this is the ONLY WAY
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look just do it
ps: P=VI,
Ah = ampere x hour
you're listening to SPL not Watts,
and read up on boundary reinforcement
ps: P=VI,
Ah = ampere x hour
you're listening to SPL not Watts,
and read up on boundary reinforcement
that's the plan. will build the system as finances allow. i just wanted to check to make sure i've planned the electronics right.
i'm quite familiar with boundary re-enforcement (put subs in corners) and planned on using a downward facing sub with my last trailer, but i want the subs facing up for aesthetic reasons... showing the woofers off, and NOT having fugly wires sticking out of the top of the trailer. i want a clean looking installation, unlike my saddlebag system. besides sounding like crap, a lot of bike systems REALLY look like crap. f i could afford it, i'd go full custom, but using cheap off the shelf car boxes it's possible to put a nice looking system together. the mains with their asymmetrical backs will be the weak link in the looks department, but i'm planning on building some kind of box grille to hide them.
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For boundary reinforcement and showing off some drivers, double the number of drivers and couple them? Point 2 up and 2 down?
Hi,
FWIW high tyre pressures are much less efficient than optimum
tyre pressures. Its pointless specifying a given PSI. It totally
depends on the tyre size and its effective loading.
This isn't a forum known for sexism, I suggest you desist.
rgds, sreten.
FWIW high tyre pressures are much less efficient than optimum
tyre pressures. Its pointless specifying a given PSI. It totally
depends on the tyre size and its effective loading.
This isn't a forum known for sexism, I suggest you desist.
rgds, sreten.
my mountain bike balloon tires are RATED at 40 PSI and absolutely SUCK at that pressure! it's like riding through mud at 40 PSI whereas the bike rolls much better at 80 psi. there's a REASON 10 speed racing bikes use 100+ PSI. lower pressure eat up efficiency in the form of tire flex and creating heat. my feet know perfectly well what rolls better and what doesn't. the crappy plastic rims on my last trailer forced me to stick with a piddly 50 PSI which, again, sucked, probably even moreso with little 20 inch wheels. my trailer rolled much smoother at 80 PSI plus, only the plastic wheel s had no lips to hold the tires. high PSI = minimal energy transfer as well as a rougher ride. when you've tried hauling a couple hundred pounds with 3 x 20 inch tires and 1 x 16 inch tire, then you can tell me what i already know about rolling resistance.
sexism? what sexism? FACT: a sexy MILF freaked on my leg, and yes, i want to use my system to attract the opposite sex. what's YOUR problem SJW? are you offended by heterosexuals? i said absolutely NOTHING demeaning about women! YOU need to take a chill pill control freak. GREAT! this forum doesn't have a mute button
again, with one cabinet facing down, ugly unprofessional looking wires will be sticking out of the top of everything. it's visually unacceptable to me. i'll be perfectly happy with whatever output i can get out of the 4 woofers facing upwards. besides, PART of my intention with this system will be showing it off as a clean installation with all wires etc. hidden. as an acoustic suspension lover, i'm more concerned with sound quality than extension. 4x97dB = 103dB per watt and at 150 (real world) watts, that should equal 124dB minus bass rolloff... nothing to sneeze at for a BICYCLE system, especially when a lot of cars only have 1 low efficiency 12 inch. i can live with whatever the limits of my system will be. i just know it will be much louder than 2 x 5 inch at 85dB driven by 10wpc. i'm not SPL drag racing, just trying to build a nice sounding system worthy of dancing to. BTW, last night i rolled with someone who has a 2x12 inch ported bike system playing vintage funk and disco tracks and even at lower cruising volumes, people were going nuts & dancing wherever we went. it was a lot of fun except for the part where i had to wait for everyone to get drinks on 3 bar stops. i headed home on the 4th stop
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a few years ago, when i had the other trailer, i paid and excellent woodworker to goof up a pair of 4 x 6 1/2" towers that were going to be internally illuminated by color changing LEDs and put in the trailer by tilting it back 90 degrees and just sliding them in only he took it upon himself to change EVERYTHING i specked and shortened the towers so he could add 1 inch foam spacers all around with the woofers so bunched together they wouldn't fit. still, i might keep that tilt idea for this system when in "parked mode" standing the woofers up on the ground and putting the mains up high on tripod stands. regardless, the system will be louder than a boombox and that's all you really need for a dance party.
one other problem with mounting the woofers facing downwards is that i'll not only be mounting the batteries, amps and wires to the bottom of the trailer, but also that down the road i want to mount downward facing color changing LEDs, possibly even projecting shapes and don't want to mount anything to the subs.
Hi,
Its got nothing to do with diyaudio, but you are a victim of a myth.
The myth is high pressures = faster, the reality is they feel faster.
MTB tyres at 80psi off road will be awful, and MTB tyres on road
will also be awful generally, whatever pressures you run them at.
The invention of the pneumatic tyre proved they had lower
rolling resistance than solid tyres by flexing over minor bumps.
Too hard is bad, what you want is optimum tyre pressure.
Optimum tyre pressure goes up the smoother the roads you
ride and goes down the rougher the roads you ride. It changes
drastically depending on the width of the tyre, lowering as the
tyre width increases, 100 psi+ may be needed for skinny racing
tyres, but is too high for most tyres sizes wider than racing tyres.
Fatter your tyres the lower the optimum tyre pressure.
The heavier you are increases optimum tyre pressures,
and that of course will apply for the loading of a trailer.
rgds, sreten.
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