In general, people don't 'mess' with a sub to hear it, on the DIY forums. They build something to suit their needs, if there is nothing commercially available. Measuring the room transfer function before anything is designed or built is the best way forward, compared to building something and hoping for the best.
I fail to see how you can manage to invest literally thousands of hours to develop and build out all of what you have mentioned while caring for a baby full time over even 10 years.
You have developed a boat previously which has not been built yet. You plan on using a 13B rotary engine to save fuel, to go 70 kms one way to fish with this thought exercise? There are a multitude of reasons why a rotary is a bad plan, not withstanding the noise, plug fouling, oil burning and apex seal issues. The continuously moving combustion chamber is less efficient than a conventional engine in converting the potential of the fuel into power output. Add in the expense of mix oil, and i'd not touch one with a 10 foot pole, figuratively.
What's the harm of a few bucks here and there? Those few bucks turn into big money over time, and this money can be used in many other ways, including investing in your retirement. You've previously mentioned that you were good at making money, not at keeping it, and I feel that if this is true, you are on a path that is somewhat self centered and your priorites may be off kilter.
To give you some context, I've built a lot of things in my lifetime, and have seen others fail at less daunting tasks.
Someone in my hometown took a perfectly functioning 1978 Corvette pace car that was only a handful of years old at the time ( 4 years old ) and started to modify it, because he felt it burned too much fuel. He took out the original Chevy small block V8, and in place of it went a tired, worn out, sludged up Chevy 4.3L V6 out of a delivery van with hundreds of thousands of kms on it, along with a 5 speed manual transmission. Extensive weight savings were attempted, the dash was gutted and fitted with a keypad and relays to start it. After almost a decade of hacking up bits of aluminum plate with a hacksaw and files, and making fiberglass parts it was ready for the road. To his dismay, the car achieved a real world 1.5mpg increase in town, despite having gone to narrower wheels and tires, lightening the car, re-gearing the final drive ratio, and replacing the engine / transmission combination.
He spent literally tens of thousands of dollars on suspension bits, tires, wheels, interior pieces, lightweight seats, and other miscellaneous supplies along the way. Those tens of thousands of dollars could have paid for the fuel to enjoy the original vehicle as it was. Instead, the money was wasted, the project shelved under rotting tarps until 2001 ( almost another decade ) before being sold for the sum of $ 500 as is for a hacked up low mileage car.
Even then, he couldn't remember the combination to the keypad to start it.
If you want a thought experiment, purchase a shake flashlight, you will get some context as to what your proposed endeavor will be. Shake it, or even lightly twist it to move the core through the magnets, and measure the amount of power output. I have a feeling that there is a reason no one else is doing it, because it's not worth doing, period.
The amount of money invested in trying to harvest 'free' energy instead could instead be used to run a generator for trouble free power when needed, the Honda inverters are quite frugal on fuel, an EU2000i/2200i would be my choice.
The amount of money invested in trying to harvest 'free' energy instead could instead be used to run a generator for trouble free power when needed, the Honda inverters are quite frugal on fuel, an EU2000i/2200i would be my choice.
Please allow me my confidence in that. Being a chronic insomniac helps too
Plenty of folks on here taking time to work out a solution to their real or perceived needs
But I have built others that work very well commercially and privately. The 13B has a following here. The bay crosser design is based on an EDF and the 13b is the cheap option. One means of crossing the bay that was ultimately discarded in favour of the electric 6m slow cat
The crazy is still there. One day I will cross the bay via GEV. I am riding the absolute peaks of tall chop at 30 knots in level trim now with 30hp 2 stroke and can WOT when everybody needs to slow down. This is also in more safety than the boats floundering in chop. I am able to bank into complete steering lock at WOT too and with 3 on board and sudden stops are safer then a regular boat too. The vessel is at marine survey too! Next iteration will target a bumpless bay crossing at around 40 knots and complete detachment from water. It really doesn't take long to make things once a plan has come together
Indeed, self-centred. An actual effort to spend some time on myself for now, trying out things that I always wonder about. Even if I can find 20mins to move things forward an inch
Think of my participation on this forum as a full-time housewife with a baby and some pocket money to buy coffee and lunch. I go without lunches and cook to get some things of interest. I won't be returning to full-time work either but a working retirement. My injuries from an accident haven't healed up the best either. Something like boat hire and soundsytem is appealing, I am finding it a bit distasteful in having justify everything to attract some help on the electronics and audio side of things
I have built many things too. The peacock neon signs around Sydney's Capital Theatre were my handiwork in 1993 and there are 10000 adult trees along Cooks River that I planted in the same year. So what?
A poor attempt!
The green Ford EL Falcon towing the boat that I made while living 3600km from the nearest chandalery has had the Ford 4L inline six replaced by a full conversion to a Nissan LD28T. Better on the slow long gravel roads and I can still hit 220kph on a particular road
My last car was a modded 4L lexus coupe to GT spec for the Nations Cup at Bathurst. Old and still running like as if on rails. Gone when the taxi industry collapsed around me. Falcon is still there back on the island
There are projects that went well and some that didnt, so what?
So what? At no point do we sit down to try to find a way away from even that? Why do you have the DIY bit in your handle anyway?
Prolly because most people prefer boneless cuts and fillets and dont kill and dress their own meats. So totally unable to even entertain connecting the neck bone to the hip bone 🙂
Please read all of the above as written with a tone of bewilderment over the attitude towards my project and my accompaning musings
But you don't have a 'workspace'. Sure, you can do some work outdoors, weather permitting in the carport.
You need to build a trailer.
Then a mobile booth as you call it for sales of music and bass amps and guitars. Then you need to build a propulsion system. Then you need to build subwoofer cabinets and something for main speakers.
Then you need to have someone weld your aluminum pipe dream together.
Randy, it sounds like you have many, many things on the go, and the amount of work you are proposing does not appear to me to be in line with reality in your 3 yr time frame, though I'd be happy to be proven wrong. I wish you luck on your journey. I certainly can't be the only one here that is bewildered with your proposals, constantly changing plans / thoughts and random purchases.
Ohm's law calculator, this may help answer some questions:
https://www.the12volt.com/ohm/ohms-law-calculators.asp
Send an email to PRD real estate in Hervey Bay asking for the availability of commercial/industrial workspace suitable for boat building with at least 9m x 5m open floor area.....they might say, "Randy has been after one of those too but there hasn't been much going around"
Might be a problem for others, especially with monohull, but not a problem with the build plan that I devised and described earlier in the thread. The pair of 6m hulls and 4 x-beams are to be transported to the water on the trailer the 6m hulls are sitting on and bolted on at the sailing club and launched with the tractor. Everything is fitted out on the beachcat which will dry dock with the moored/berthed hulls. Let's hope that the workspace at home that I built this large double axle trailer in will suffice
The only structural welding work required is two of the x-beams in a U shape to form the dry dock between the bows for the beachcat. This is the only welding that that needs to be done by a certified welder. The rest I can do myself
The trailer the 6m hulls are sitting on took me two days to build, get passed and registered. Can you elaborate on the difficulty that you are sensing? The new trailer to be built is only a lil one for the beachcat/booth. Can be put together in a few hours. There is very lil to making a trailer
Sounds like good wholesome DIY fun. I'll ask again, whats with the DIY bit in your handle? Are you not able to bring forth as imagined on the fly? It enables things to just come together after a bit of ponderings. Are you not able to do a simple thing like taking a scrap of alloy, 'seeing' the lines of each component of a dual lever, interlocking remote control box for a set of forward controls and scratch it out and cut it out with a grinder and file it down and bolt it together and it jsut works as expected? I see this radiation from everything
We have very different ideas about how long it takes to make something. Please bear in mind that the pondering stage is the fun bit. After the fight I put up to break out of a very bad situation to something very comfortable, I am allowed a little shopping therapy and to be absolutely wilful. No harm done to anyone so whats the problem?
With the current round of pay in 4s completed, time to add some missing bits like a couple of 3 phase bridge rectifiers, clamp meter, laser tacho, thermometer gun, 1.8kw up stepper to get the 48v for the ebike controller and audio modules. Another 400w up stepper for the water toy. As well as another MPPT charge controller that was on super clearance. I have a biz account with Ali and got some savings over the listed price. A webcam too to make vids of the experiments and such to present here. I'll just have to give up three cups of coffee a fortnight to afford the pay in 4 for these items 😉
Today at the beach was some of the heaviest conditions for launch. The marching short waves were standing up with enough power to slam people over. These conditions will prevail through to April and change to a long roll back through winter into spring. There is a behaviour in this statement that I once again connected to the first exploit that I had worked out. So, I tested to see if the exploit would give the expected result and it does
Did some study with buoyancy and managed to figure out how to use the exploit for harvesting with both the elliptical and the private idea. There is also an excess of wave power with just a foot of chop like yesterday for the elliptical due to being fixed at human scale but I am also correct in predicting that the excess runoff can be harnessed as an upward force moving something sideways. Tomorrow, I will examine some kayak buttocks to see if the built-in sorta cathedral in some fishing types can be used to direct this flow to add hydrodynamically to the thrust. There are usually a bunch at the reuse centre for around $10 each!
Some have splits and such, but HDPE welding is amongst my skill set. If I can find the right type of buttocks, then the kayak can serve as the central nacelle and save making a mid-hull from scratch. The bow shape doesn't matter, as the sci-fi drive was designed to make that aspect redundant As far as forward motion is concerned, there is no hull behind it!!! The power of advances in SWATH :O
The x-trainer will fit on this kayak and connect to the forward x-beam of the cat via a pivot joint and the rear x-beam via strut suspension. GM said in another post that a speaker is just a solenoid. The struts are a needed part to connect the ebike drive to the boat proper while providing the rider some decoupling from the motions of the boat and remaining fairly relaxed supported on SWATH. This means that the struts will always be working, and I want to turn them into such solenoids that can gen working in reverse. Those are the 1m xlimit subs that I was talking about
Another good outcome from today is the subwoofer dimple array under deck idea to regen. Building on an idea that I already mentioned earlier to lift gen efficiency. Buy a setup that has the coils and mags in around a 1.5kw 48v config. Flip it horizontally and connect the cone via custom push-pull cable wound once around a spool over the magnets. It costs about $200 to buy, and I happen to have one lying around to mess with 😀 The ehub
Also on the to-do list. A few months ago I tried to make a couple of 8" PR units and with good results. Will have to make 4x 12" PRs for the pair of Polk subs
Today at the beach was some of the heaviest conditions for launch. The marching short waves were standing up with enough power to slam people over. These conditions will prevail through to April and change to a long roll back through winter into spring. There is a behaviour in this statement that I once again connected to the first exploit that I had worked out. So, I tested to see if the exploit would give the expected result and it does
Did some study with buoyancy and managed to figure out how to use the exploit for harvesting with both the elliptical and the private idea. There is also an excess of wave power with just a foot of chop like yesterday for the elliptical due to being fixed at human scale but I am also correct in predicting that the excess runoff can be harnessed as an upward force moving something sideways. Tomorrow, I will examine some kayak buttocks to see if the built-in sorta cathedral in some fishing types can be used to direct this flow to add hydrodynamically to the thrust. There are usually a bunch at the reuse centre for around $10 each!
Some have splits and such, but HDPE welding is amongst my skill set. If I can find the right type of buttocks, then the kayak can serve as the central nacelle and save making a mid-hull from scratch. The bow shape doesn't matter, as the sci-fi drive was designed to make that aspect redundant As far as forward motion is concerned, there is no hull behind it!!! The power of advances in SWATH :O
The x-trainer will fit on this kayak and connect to the forward x-beam of the cat via a pivot joint and the rear x-beam via strut suspension. GM said in another post that a speaker is just a solenoid. The struts are a needed part to connect the ebike drive to the boat proper while providing the rider some decoupling from the motions of the boat and remaining fairly relaxed supported on SWATH. This means that the struts will always be working, and I want to turn them into such solenoids that can gen working in reverse. Those are the 1m xlimit subs that I was talking about
Another good outcome from today is the subwoofer dimple array under deck idea to regen. Building on an idea that I already mentioned earlier to lift gen efficiency. Buy a setup that has the coils and mags in around a 1.5kw 48v config. Flip it horizontally and connect the cone via custom push-pull cable wound once around a spool over the magnets. It costs about $200 to buy, and I happen to have one lying around to mess with 😀 The ehub
Also on the to-do list. A few months ago I tried to make a couple of 8" PR units and with good results. Will have to make 4x 12" PRs for the pair of Polk subs
If you are raising that as a point, then it means issues such as not having a 'workspace' is a limiting factor for you not to try
or
In arrogance, are implying that while it doesn't limit you, it should limit me
Which one is it?
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I keep making these word heavy posts to think out aloud and sort out an iron the developments in my own way. Writing them down like this helps me keep track too and share my thoughts with anyone who can keep up
Had a lot to share, so missed one important update. By using a dual vc at 90 degrees to each other, can generate 30v with two fingers. When the watt meters and clamp arrive, I will be able to work out the power produced (still trying to figure out what to use as a realistic load, one that doesn't under or overload at various simulated wave periods)
Around the same physical size as a cheap 8" woofer with a small magnet, but with the cone inverted to a dome. The 30v is around 30-40mm xmax, will measure when correctly loaded for realistic result. Free running, A 9 unit array might be cool. A full bridge rectifier on each vc and rectifiers paralleled to lift current per unit. Then create a series parallel array with the 9 pairs of doubled rectifiers. Is there a less twisted than 72 diodes to combine 18 voice coils into something an MPPT charge controller can use?
No one wants to assist with custom coils. What would be the reasons for me to detail the how?
Had a lot to share, so missed one important update. By using a dual vc at 90 degrees to each other, can generate 30v with two fingers. When the watt meters and clamp arrive, I will be able to work out the power produced (still trying to figure out what to use as a realistic load, one that doesn't under or overload at various simulated wave periods)
Around the same physical size as a cheap 8" woofer with a small magnet, but with the cone inverted to a dome. The 30v is around 30-40mm xmax, will measure when correctly loaded for realistic result. Free running, A 9 unit array might be cool. A full bridge rectifier on each vc and rectifiers paralleled to lift current per unit. Then create a series parallel array with the 9 pairs of doubled rectifiers. Is there a less twisted than 72 diodes to combine 18 voice coils into something an MPPT charge controller can use?
No one wants to assist with custom coils. What would be the reasons for me to detail the how?
Very new to doing this but looks like 1.5A 30V with finger push. So 45w per vc. I think will be better to series VC for higher voltage
It needs 3Nm for full stroke and the number s are 45v 1.5A per coil. Without roll surround and just riding a centre pin. A ball/dome cone will be needed to push with at least 3Nm to get the numbers on paper. Can push harder by hand once a dome is on. Need to work out a spring for good return. Magnet/coil dia 50mm and height 100mm. Total motor structure and 'cone' and basket lifted a bit to around the size of a 10" subwoofer with a very tall 100-150mm tall neodymium motor structure
Will need to make a basket to hold this and the pin with the ball. A stainless floating shaft and its bronze components from Penn spares department is around $30 and can serve well here to hold the dome and magnets. Coils are fixed to the housing. Let's be a bit conservative for any losses from the floating shaft (originally engineered by Shimano to eliminate this loss) and rate this at a good 100w 90v pulse per wave. I am considering an array of 10 units in parallel now, adding one at a time with spare funds
Total unit cost for the prototype will be around AUD $60. But getting parts for 10 units places me in the wholesale price per lot
We could have arrived at those results and prolly better working together, and I still can't fathom why you guys don't want to be a part of this and the difficulty with deciphering the ramble
Here is another detail that I just realised while thinking about the xlimit. The length of the movement can be up to 1m. I am doing the 100-150mm tall for ease of construction for the under deck array. This thing can run the full wave with a long enough floating shaft, making a very long pulse of around 2 seconds each
The hand bone connects to the nek bone 😉
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I think it was in the 90s when I read a mention from Bob Carver about having to overcome back EMF from the original Sunfire subwoofer drivers. This has been haunting me for half a lifetime. When you folks started bringing up the cons of solar and wind earlier in the thread, this jumped out as a foul free way of engaging the waves to utilise that back EMF
Sub gen
Solved the actuator setup ina crazy way. If I fit 4x the motor structures to the dome cone, It becomes self-supporting on a DIY pin and no longer need the Shimano type floating shaft setup. Also makes it easier to better centre the xmax within the xlimit of the housing. The voltage produced over the 8x coils would remain that 30v fingered, but power would go up 4x. Due to the 4 structure being in parallel. At one time, I used to get NiTi alloy wire guides made up in the hundreds. I have it within my skill set now to make a restoring coil spring for the 'spider' by creating a shape memory in straight wire using heat
A successful roll surround that can handle 60mm of peak to peak would be best to seal off the dome from the assembly to prevent water ingress. Since its not for audio playback, might just get away with one roll surround passing to another in dual concentric to get the 60mm of travel. The centre pin can keep things linear. Been thinking for a while to finish of the custom PR units but when I raised the pin and NiTi spring in an earlier discussion on custom PRs, no one could imagine the config
After a recent exchange on the forum on vc heat losses, the Re for each vc set at 1R. I have no idea how to do the maths on the two vc being placed in series after a full bridge rectifier on each and don't know if this is the best way to sum the power or to series the coils and then rectify
It's meant for gen, but I am keen to hook this up to an amp to see if it can make bass too. I think series parallel of the coils to 4R or so to one pair of input leads to the amp will do
I am being deliberately vague about the details, but all the clues are there in the salad to date. To explain, will come with the finished prototype if it works as expected. There is a field that is slowly growing on this forum. Anyone familiar with making the tools for that should twig on already as to where I borrowed the nek bone from
Anyone still standing their ground on the pointlessness of making a subwoofer derived device to wave gen?
Etrike
Lucky, it only needs just a few machined/printed parts. You folks would prolly call this a dysfunctional vehicle too since the systems are borrowed from the beachcat
There is around 20L gross under the seat for the subwoofer box, amps and ehub controller. Can anyone think of other drivers to give a run here?
Solved the actuator setup ina crazy way. If I fit 4x the motor structures to the dome cone, It becomes self-supporting on a DIY pin and no longer need the Shimano type floating shaft setup. Also makes it easier to better centre the xmax within the xlimit of the housing. The voltage produced over the 8x coils would remain that 30v fingered, but power would go up 4x. Due to the 4 structure being in parallel. At one time, I used to get NiTi alloy wire guides made up in the hundreds. I have it within my skill set now to make a restoring coil spring for the 'spider' by creating a shape memory in straight wire using heat
A successful roll surround that can handle 60mm of peak to peak would be best to seal off the dome from the assembly to prevent water ingress. Since its not for audio playback, might just get away with one roll surround passing to another in dual concentric to get the 60mm of travel. The centre pin can keep things linear. Been thinking for a while to finish of the custom PR units but when I raised the pin and NiTi spring in an earlier discussion on custom PRs, no one could imagine the config
After a recent exchange on the forum on vc heat losses, the Re for each vc set at 1R. I have no idea how to do the maths on the two vc being placed in series after a full bridge rectifier on each and don't know if this is the best way to sum the power or to series the coils and then rectify
It's meant for gen, but I am keen to hook this up to an amp to see if it can make bass too. I think series parallel of the coils to 4R or so to one pair of input leads to the amp will do
I am being deliberately vague about the details, but all the clues are there in the salad to date. To explain, will come with the finished prototype if it works as expected. There is a field that is slowly growing on this forum. Anyone familiar with making the tools for that should twig on already as to where I borrowed the nek bone from
Anyone still standing their ground on the pointlessness of making a subwoofer derived device to wave gen?
Etrike
Lucky, it only needs just a few machined/printed parts. You folks would prolly call this a dysfunctional vehicle too since the systems are borrowed from the beachcat
There is around 20L gross under the seat for the subwoofer box, amps and ehub controller. Can anyone think of other drivers to give a run here?
Randy: the Incredible Hulk or Magneto?
So you can get half the power with a finger push as typical people can sustain with their whole body, which after mechanical conversion losses is reduced to ~25% electrical output 🙄.
The clues are easy to see: when you are several orders of magnitude off in figuring the potential of your "very new" endeavors, impossible outcomes appear easy to achieve.
Similar to your Cub Sandwich thread, where your simulations were off by more than an order of magnitude, but you had no clue:
A subwoofer derived power generation system will take up far more of the limited space available on a small watercraft, while also costing and weighing far more per watt output than a permanent magnet rotary generator.
If your point is to build a boat that demonstrates inefficiencies, you're on the right track!
Art
This thread looks to be a train wreck of rambling OT material. If it doesn't get back on track it will be closed.
For stuff not directly related to audio we have 'The Lounge'.
Dear Mr Moderator
Gen is definitely off-topic. Solar adopted as top up for an off grid sound system project that is definitely bass heavy. Project slowed down with members chiming in regarding the inefficiencies of solar and wind on water
Please take note that I have been bringing up subwoofer back EMF for quite a while now in other prior discussions wishing to learn more about this and describing how this has been on my mind since Bob Carvers mention of having to tame this. It's been on my mind for some time to find a way to use this as its a closed system behind the diaphragm and something that 'EMFs' without blades or the constraint of a particular time of the day
Do you feel that the lounge would be the best place to document the equipment, process and method to make custom DIY:
1 - Roll surrounds with large xmax
2 - Composite cones
3 - Rotary motored subwoofer
4 - Passive radiators with large xmax
5 - Methods to create a large xmax with a linear motion and very compliant movement
6 - Front end transport cases
7 - Waterproofing of amplifier modules and such
8 - Marine grade subwoofer enclosures
9 - Personal mobile subwoofer systems
10 - Off grid power for large subwoofer arrays
11 - Massaging the iron law to bring down enclosure sizes
There is a stage of pondering that goes hand in hand in the predevelopment stage. If this stage is best served in the lounge, then please relocate the thread there. We can always look at brining it back here at a later stage or separate the topic into a number of different threads all over the forum in the specific areas
It is not my style to use distasteful words and my apologies in repeating the words and sentiments directed to my person or project during my response to request to watch it fold out or take a closer look
I have been brought up in a word heavy text environment and assume this the normal case for all. Rambles and ponderings are the gears that grind things down to working solutions. also known as the preamble. It's a big project and things will fall in place. Your intervention though is at a point where most of the systems are worked out and will be presented in a pictorial build process
Is there a time limit as to how long to take to first create a whole that doesn't compromise each part?
Dear Mr Moderator mon
Moving forward. Have edited the first post now that each system is sorted. This goes beyond this thread and what I have been working towards for the past year, spread amongst a number of threads and at various stages already. All are tied together so will be presented in the ongoing in mostly pictorial form with an open invite for discussion or elaboration on any aspect
Thanks and regards
Randy
Tiny40s
First task is breaking in the racer driver for the Tiny40s project. I am fitting this to a z623 cab and will let it run overnight
First task is breaking in the racer driver for the Tiny40s project. I am fitting this to a z623 cab and will let it run overnight
The thread must stay on topic, its a simple as that 🙂
The same rules apply to everyone. Keep it on topic and relevant to subwoofers and diy audio. If that doesn't happen then the thread will be locked.
Planes, bikes, trailers, the weather, swimmers... non of that belongs in this forum. This thread seems to have become a journal for your day to day interests and activities as much as anything.
Mr moderator, I already agreed to focus mostly on the bass, I am not a delinquent and tire of repeated threats
I will state this much, if linear and switching PSU's are on topic for a highly integrated subwoofer design than so is live gen as PSU
Payload, windage and space are equally on topic as WAF or placement around living room furniture. All of these are constraints on shape, volume, qty deployed and appearance
Think on this, multiple units allow higher system efficiency for given power but at the cost of space, weight and cost. These are important things to work out
Working all of those out is a required step for an integrated subwoofer
It's a constant obsession with basslines and the transducers and cabs that produce that. Even the swimmers are something to design acoustically away from or towards to fire 😉
It is already clear that we do not share the same point of view as to the legitimacy of the constraints faced by my project as being equally important as those raised with any other subwoofer projects such as the examples of WAF, placement and directivity
If you haven't already worked out, the project is making listening to basslines as much part of my everyday life as possible. This means making lots of different subs and things that can fit subs
Please take the time to go through the ramble and see how hard I have worked daily to either work around or accommodate those constraints so that I may successfully have a pair of 12 Inch subwoofers on board a very limited vessel
I feel quite dejected regarding the moderator intervention. With the belief that the statement of requirements is headed by the average 96dB of onboard bass being able to be produced around the clock on a marine platform that displaces not that much more than the subwoofers cabs
Pondering, revisions, doubters and naysayers are part and parcel of some bit projects coming together and motivation to 'nail it'. My mind has been too negatively charged and preoccupied by this to do much at the moment
Pondering, revisions, doubters and naysayers are part and parcel of some bit projects coming together and motivation to 'nail it'. My mind has been too negatively charged and preoccupied by this to do much at the moment
OK, skipped to post 156..
Rather than feeling dejected and negative, why not post results of your "first task" in the real development work?