Marine subs
https://au.polkaudio.com/-/media/Fi...kAudio_Product_Documents/db-sub-infosheet.pdf
Considering these for long term peace of mind. 4 of these wired for total 4R and placed on the amps bridged rear channels should yield 95dB with 1w. That's close enough and still cheaper than a pair of 18s on either boat. I'll start with one pair and see the output and draw and such
Two vessels and a booth makes for a bit of a jumble to sort out. I don't want to end up with redundant systems, and every kg matters on the water. Have to find that balance
4x Polk cabs would make for a good marine grade sub array for hire use and I can promote them from the tender
Tender is the heart of the big boat
Bass Shelter can stay on land with the dry use sub
I do have a more suitable vessel to use as a tender for carrying capacity but enjoy the idea of a light beach cat. All these grey HDPE hulls have the same designer
https://au.polkaudio.com/-/media/Fi...kAudio_Product_Documents/db-sub-infosheet.pdf
Considering these for long term peace of mind. 4 of these wired for total 4R and placed on the amps bridged rear channels should yield 95dB with 1w. That's close enough and still cheaper than a pair of 18s on either boat. I'll start with one pair and see the output and draw and such
Two vessels and a booth makes for a bit of a jumble to sort out. I don't want to end up with redundant systems, and every kg matters on the water. Have to find that balance
4x Polk cabs would make for a good marine grade sub array for hire use and I can promote them from the tender
Tender is the heart of the big boat
Bass Shelter can stay on land with the dry use sub
I do have a more suitable vessel to use as a tender for carrying capacity but enjoy the idea of a light beach cat. All these grey HDPE hulls have the same designer
Still pondering config
I feel that 2x Polks would be plenty for vessel use. The money and space saved would be better spent beefing up the 72v bank with more run time
4x Polk cabs would make for a good marine grade sub array for hire use and I can promote them from the tender with one pair and store another pair in the booth
Smartwave, hard docked as a central outboard power nacelle towards the rear of the larger vessel. Permanently left on the water
Beach cat, light duty tender and docked alongside the larger vessel and trailered home
Bass Shelter can stay on land with the dry use subs and extra marine subs plus rest of the hire gear
Trailer, use the current trailer from the Smartwave then build a new one later. This trailer will be adapted to take on either the Smartwave, the beach cat or the booth
Sorted!
I think!!
I feel that 2x Polks would be plenty for vessel use. The money and space saved would be better spent beefing up the 72v bank with more run time
4x Polk cabs would make for a good marine grade sub array for hire use and I can promote them from the tender with one pair and store another pair in the booth
Smartwave, hard docked as a central outboard power nacelle towards the rear of the larger vessel. Permanently left on the water
Beach cat, light duty tender and docked alongside the larger vessel and trailered home
Bass Shelter can stay on land with the dry use subs and extra marine subs plus rest of the hire gear
Trailer, use the current trailer from the Smartwave then build a new one later. This trailer will be adapted to take on either the Smartwave, the beach cat or the booth
Sorted!
I think!!
Sorted
I have a good strategy now, this should be highly workable and reduce doubling of gear a lot
2m wide x 3m long light booth with aluminium framing and foam core walls. Short height with pop top roof, standing room at stern and shorter at the bow. The side windows to fold up and hold up the deployed roof. Walk through hatch at the bow end (door) open at back with a half height fold up tail gate. A counter at the stern. Central double deckchair with padded top
In the booth, one pair of 12" Polks subs, A waterproof housing to secure my laptop, audio interface and other sensitive electronics. Access via a panel mounted touch screen. Serrato DJ software will suffice for marine use and the virtual decks can be put up on the touch screen together with a waterproof mouse in the mix. Also, ina waterproof housing and heat sinked to the outside, TPA32xx based power amps for the subs and mains. Much more cost-effective than a marine amp
48v LiFePO4 bank to supply the amps and a 48v 6kw petrol range extender. Roof full of solar and supporting that bank during the day. A 240v AC inverter hooked up to this bank, if there is such a thing for 48v systems. A 12v and 5v step down system would also be handy taps
Up the tender displacement by 250kg with a new central hull, turning it into a tri. This central hull will be like a planning pad for the tender. The tender beach cat hulls are light and can be carried by a person. So they will be kept of the booth roof and just pick up and slotted into the middle hull sides and locked in with tow-bar tongue shear pins
The larger vessel will dock the Smartwave at the stern and under the deck. The beach cat with the booth will pull up into the fore deck dry dock cradle thing. The Smartwaves outboard will be the larger vessel's main drive and the electric drive from the beach cat will be its cruise drive
This drive will need to be on a long leg to make it to the water in the docked position. I can use an electric drive for the jacking plate. The very large transducer for the Raymarine Axiom 9" 3D/side scan/nav console will be fitted to an independent system that can be slotted onto either craft
The trailer will have a secure locker holding the hire PAs. The tender hulls can be left at home when working markets and festivals
This gives config gives me mooring security for the larger vessel
Only one trailer, with a secure locker
Work booth that doubles as family rec camper
A 6m x 4m mothership
Fast and safe aux boat with a 30hp outboard
A day use beach cat that is easy to tow with the booth for holidaying via road
Only one trailer to park, I can repurpose the Smartwave trailer so no need for a new one
Big trailer can be sold to fund the hybrid powertrain
The large vessel has a 3000kg displacement to initial waterline and sinks 100mm for further 1000kg payload. As work brings in money, I can slowly upgrade the power train to another pair of 30s on the back of each main demi hull as well double up on the electric drive
So, plan sorted with a total approach that is very feasible and works out surprisingly cost-effective through the solutions that I have come up with to bring everything together
Thoughts?
I have a good strategy now, this should be highly workable and reduce doubling of gear a lot
2m wide x 3m long light booth with aluminium framing and foam core walls. Short height with pop top roof, standing room at stern and shorter at the bow. The side windows to fold up and hold up the deployed roof. Walk through hatch at the bow end (door) open at back with a half height fold up tail gate. A counter at the stern. Central double deckchair with padded top
In the booth, one pair of 12" Polks subs, A waterproof housing to secure my laptop, audio interface and other sensitive electronics. Access via a panel mounted touch screen. Serrato DJ software will suffice for marine use and the virtual decks can be put up on the touch screen together with a waterproof mouse in the mix. Also, ina waterproof housing and heat sinked to the outside, TPA32xx based power amps for the subs and mains. Much more cost-effective than a marine amp
48v LiFePO4 bank to supply the amps and a 48v 6kw petrol range extender. Roof full of solar and supporting that bank during the day. A 240v AC inverter hooked up to this bank, if there is such a thing for 48v systems. A 12v and 5v step down system would also be handy taps
Up the tender displacement by 250kg with a new central hull, turning it into a tri. This central hull will be like a planning pad for the tender. The tender beach cat hulls are light and can be carried by a person. So they will be kept of the booth roof and just pick up and slotted into the middle hull sides and locked in with tow-bar tongue shear pins
The larger vessel will dock the Smartwave at the stern and under the deck. The beach cat with the booth will pull up into the fore deck dry dock cradle thing. The Smartwaves outboard will be the larger vessel's main drive and the electric drive from the beach cat will be its cruise drive
This drive will need to be on a long leg to make it to the water in the docked position. I can use an electric drive for the jacking plate. The very large transducer for the Raymarine Axiom 9" 3D/side scan/nav console will be fitted to an independent system that can be slotted onto either craft
The trailer will have a secure locker holding the hire PAs. The tender hulls can be left at home when working markets and festivals
This gives config gives me mooring security for the larger vessel
Only one trailer, with a secure locker
Work booth that doubles as family rec camper
A 6m x 4m mothership
Fast and safe aux boat with a 30hp outboard
A day use beach cat that is easy to tow with the booth for holidaying via road
Only one trailer to park, I can repurpose the Smartwave trailer so no need for a new one
Big trailer can be sold to fund the hybrid powertrain
The large vessel has a 3000kg displacement to initial waterline and sinks 100mm for further 1000kg payload. As work brings in money, I can slowly upgrade the power train to another pair of 30s on the back of each main demi hull as well double up on the electric drive
So, plan sorted with a total approach that is very feasible and works out surprisingly cost-effective through the solutions that I have come up with to bring everything together
Thoughts?
With more thought, refined it further. I will set up a 4 way docking system
The Smartwaves seaworthiness is not to be underestimated. It's like a mini 4WD of the sea. Smartwave as utility craft. Smartwave docked under the beach cat, forming a tri for extended over the water use and holidaying by road. The lot can dock with the mothership, Smartwave can undock leaving the mothership. The beach cat can also undock with or after the Smartwave. Smartwave can dock with the trailer
Electric hybrid beach cat for day use, with booth for day use at the beach. Can dock with the Smartwave, trailer and mothership. 6kw electric hybrid with twin motors. One on the back of each hull
Booth, fold down roof, can dock with trailer and beach cat
The Smartwaves seaworthiness is not to be underestimated. It's like a mini 4WD of the sea. Smartwave as utility craft. Smartwave docked under the beach cat, forming a tri for extended over the water use and holidaying by road. The lot can dock with the mothership, Smartwave can undock leaving the mothership. The beach cat can also undock with or after the Smartwave. Smartwave can dock with the trailer
Electric hybrid beach cat for day use, with booth for day use at the beach. Can dock with the Smartwave, trailer and mothership. 6kw electric hybrid with twin motors. One on the back of each hull
Booth, fold down roof, can dock with trailer and beach cat
Some multimeters can measure up to 10 amps, others ~300ma (.3amp). The TPA3221 probably draws under a watt (1000ma) at idle.
Since you are going to have loads (boat motors etc.) that draw far more than 10 amp, probably invest in a clamp meter that can read up to 600 amps.
Pink noise would be more similar to the dynamics of music than sine waves.
Without a speaker load the amplifier won't draw much current.
The speaker's sensitivity will determine how much power used to make 96dB at one meter.
An 86dB 1w/1m speaker will draw 10 watts to make 96dB, about all the TPA3221 can do at 12v with an 8 ohm load.
I think the subwoofer for your proposed project will be a tiny fraction of the work, and the multi-purpose concept will compromise it's usefulness.
“A boat is a hole in the water you throw money into” has been a pretty accurate description so far for me, but I've had fun doing it 😉 .
I found the more systems added, the more failure modes occurred, often at the worst possible time.
Cheers,
Art
Economy true RMS auto range
Looks like only 10A for AC. Will get a clamp type as per your recommendation. Is there a decent power meter like the SMD devices but at a better value price that you can also recommend?
Determining the draw at comfortable ambient and max levels will help to work out the LiFePO4 bank. I think I can fit 4x 100AH in series, but this only gives me 100AH @48V total. Would need 4 more packs to double that capacity, and that would be impractical (pardon any incorrect use of jargon)
Struggling with determining if 100AH at 48v would be sufficient to run a quiet ambient volume at night without the EVRE kicking (EV range extender)Can easily carry 600w of that eBay panel linked earlier. I wonder how much can they help unload the battery during day use? Let's assume a pair of those Polks and two of these boards linked below for the subs and mains for marine use. I can make a waterproof housing for the amps
Dual-core TPA3255
I am unsure of settling on 48v system in conjunction with the range extender. I hope I am right that it makes for a good PSU for the TPA32xx amps and designed to quickly top the bank back up and saves on getting a separate generator
Let's make an allowance for nighttime non-marine use with the option of running a pair of those SBA Rosso 18s to get better system efficiency (stored in the trailer locker until needed)
That is the amp for the portable audio bench cab
The marine booth use would be two of those 86dB subs on the linked dual-core board and the 48v 100AH bank. Struggling with the draw for that 96dB max ambient. Does 10w sound about right?
They also make for the largest on board items and the largest long term drain on the battery bank
I agree with you re complexity and scope
Started a list for the electrical system. This will be hosted and updated in the original post. Trying to sort out the jumble and build a plan of attack
Blanket solar 300w
I think this type will suit the marine use better. It will be interesting to start with this on the portable audio bench and see how well it can support two of these modules linked below as the built-in bench amps. This is the one with the single 12v 10AH LiFePO4 battery. Will be interesting to see if it can run the amps with the battery acting as a buffer for that 96db average SPL
TPA3221
If this panel works out, It will be a neat addition to the project BOM with 4 units to start off with on the roof of the booth plus the EVRE as the charging system for the 100AH 48v LiFePO4 bank. The Dual-core TPA3255 amps would run directly off the battery bank. Looks like there are plenty of choices for 48v to 240v inverters for running some things
I think this type will suit the marine use better. It will be interesting to start with this on the portable audio bench and see how well it can support two of these modules linked below as the built-in bench amps. This is the one with the single 12v 10AH LiFePO4 battery. Will be interesting to see if it can run the amps with the battery acting as a buffer for that 96db average SPL
TPA3221
If this panel works out, It will be a neat addition to the project BOM with 4 units to start off with on the roof of the booth plus the EVRE as the charging system for the 100AH 48v LiFePO4 bank. The Dual-core TPA3255 amps would run directly off the battery bank. Looks like there are plenty of choices for 48v to 240v inverters for running some things
10A should be enough to measure the idle load of your 12vDC items individually.
If you are running 48Vdc, 10A is 480 watts.
I found my clamp on meter by the side of the road about 20 years ago, so haven't been looking for better values 🙂
100AH at 48v is 4800 watt hours, you could run 480 watts average for 10 hours with no sun.
480 watts average could peak at over 3000 watts. Your neighbor complains at a few watts..
Two subs gains +3dB 1w/1m, so 89dB +10dB=99dB, under 10watt peak, ~1.25 watts average unless you are playing sine waves.
The HardKorr Portable Solar Blanket is a decent deal for a camping foldable panel, but has poor power density 1.43 meters 1.43 meters is big for only 300 watts, around 25% less than standard, and an odd shape for expansion.
May not last long in salt air, or it would say "for marine use". Hardkoor does not list any panels under the "outdoor and marine" menu.
Panels have to meet a standard called IEC 61701 to be suitable for installation near the sea.
Standard monocrystaline panels could go 24 or 48v, get more power per $$ and square meter, and the bimini would be easier to support, since they already have a frame.
Art
Thanks man. Also re the solar. The tips are very welcome. I'll look for a marine type
I have the means to create a floating porch with a SUP. Anyone interested in exploring a bit of wave action power generation? A bit of rope wraped around a motor shaft spool should create a churning action as the porch goes up and down. Can this create AC, be regulated to a charge voltage? A marine brushed DC trolling motor taken out and fitted with a spool as the generator? Even a 50w trickle charge would be handy and keep working at night
As my dad (r.i.p.) used to say: "the problem with free energy is it's so expensive."
This is my beachcat. It makes a case for free energy that is not too expensive if approached the right way
Anyway, that massive aluminium bridge deck structured is engineered for the forces from sail loading. This will be replaced by a framework that bolts to those cross-beam hard points
The overall width will be a road legal max 2m. The length of the deck will be set after some flotation tests but expected to be at least 2.4m long. A standing room roof will be a must towards the back. This would have slant with a shorter front. I am happy for max roof coverage. There has to be some walls, even if they are waist high. Some wall areas can be a like slatted screen with curtains. I can make a sewing machine dance, so fabric work is no issue
Performance for this vessel will be defined by economy and efficiency factors. The highest performance mark would be an entirely self-sustaining propulsion powertrain to 6 knots with its attached audio system. This audio system needs to nail subwoofer system efficiency to meet the performance challenge
This vessel is the one that will be docked between the larger hulls occasionally to create a more seaworthy vessel for extended trips. The following vid shows an extreme case build for a vessel to transport very heavy machinery. The second half of the vid shows on the plane performance in regular seas
What do you guys think? I feel it's a fairly easy build craft wise. Does my approach to the powertrain and audio so far seem like a reasonable plan?
The beachcat looks fun, but not much displacement, and with almost no rocker, the hulls dig into relatively small waves.
Still have memories of flying through the air on a wire after a friend pitchpoled my 16" Prindle cat.
Everything I've read (and saw while in Australia) says 2.5 metres is a legal trailer width not requiring any other special considerations.
So far you have presented many different ideas, but I don't recall seeing a powertrain and audio plan.
Attachments
Plus the 48v 100AH bank under consideration and the solar panels, not yet decided
That's the powertrain and audio system. One system. Only the electric thrusters will be fitted to the beachcat, the rest of that list are marked for booth install to meet those goals for not doubling up on the gear. Looking at a marine grade Android head unit as the system heart and filters for the channels. And the Yamaha AG06mk2 ina waterproof compartment for live inputs for mic and bass. As well as a fanless embedded CPU type mini pc in that compartment and a DIY type touch screen on the counter top for my virtual mixing decks and Windows access
The main pro audio front end mixers and synths will be in travel cases with clear lids for only land and larger vessel use
The mobile audio bench project is independent of the above and aimed for the workshop
Original post is being kept updated with the preliminary BOM
This is true for when rigged for sail, as the load pitches the bow down. When powered from the stern, sail hulls tend to pitch up due to the shape of the buttocks. As the throttle goes up, so does the nose
The Tennant hull solves this issue for both under way and at anchor. I have used this before with success as the last boat that I built, The feature can be built as a set of wings on the prop hub. Basically foil assist for level motion. Wave piercing is ok, it's the stabilising feature through the chop with the plumb bows. But the native tendency of a sailing hull is to pitch up when powered from the stern. The foils are to counter that and will have trim and tilt for setting the poise to the conditions when under way
Bugger, I went to the transport office to register the big trailer a while back and was told that it was at limit at it's 2m and the hulls couldn't be built any wider. I have been working with the spec from a bush turkey for the past two years. I didn't even bother to check up since the info had come from the source
Cool, 2.5m makes it easier to work with
I pulled the hulls out from storage yesterday. They will need a bit of clean up. I also pulled out the 50lb rated 12v trolling motor to setup as the drive for it for upcoming COG and sink tests. My 110AH AGM should be plenty for this use. I bought both together for use on the Smartwave, but not yet fitted due to recovering from a bad leg injury over the past year. I hope the new battery is still usuable after all that time
Last edited:
Today I ordered the pair of Polk marine subs
https://www.polkaudio.com/en-us/product/car-and-marine-speakers/db1242-svc/112444.html
And two of the dual-core modules for mains and subs
https://www.aliexpress.com/item/100....order_list.order_list_main.10.77481802zj2OBh
These amps will run from the 48v LiFePO4 bank, but they are still to be acquired and may be a while yet, as the new boat powertrain will be funded from the sale of the large trailer once the hulls are permanently moored. At that time I will splurge on a decent bank and charging
For now, the powertrain for the beachcat will be the 65lbs 12v marine trolling motor and 120AH AGM already acquired over a year ago and kept new in storage
SWNG 65/54 (SHADOW MK II)
https://cdn.shopify.com/s/files/1/0551/9733/5740/files/Watersnake-Shadow-MK-II-Manual-2018.pdf
This can only supply 12v to the amps, but I have that 12-26v up stepper that I can use in the meantime. These things are cheap, so I might get a 12-48v up stepper too
Will use the 54lbs motor to sort out the power requirements for the craft and see how much more power do I need to get that 6 knot cruise speed (mackerel trolling speed). My proposed 48v powertrain is only dual 2.5kw BLDC motors and may not reach the target speed. There are other considerations like prop dia and pitch as well as motor KV rating too
Smaller props and high speed motors are good for better top speed but take longer to accelerate. I will be able to work out the type of prop and RPM that suits the hulls after running the 65lb Watersnake for a while and swapping out props on that. I may end up building my own thrusters using motors and custom props. The newer toroidal props would be safer around swimmers, and it's likely that I will need a larger prop on a lower KV motor for displacement speeds
I really want to push all the project subs during testing phase using the mobile bench at the boat ramp car park. My 1000/1 JL amp developed issues a while back and this thing is half my age and has had a very tough life. I have always felt that the amp felt knee capped. This is due to its poor dynamic ability. I need a class d true kw class mono amp that is 1R stable as the gorrila amp in the car to drive my 12W7 and any subs getting tested at the ramp. This prolly means an amp with a true 2kw dynamic ability by my reasoning. The JL amp just doesnt have that burst legs
Recommendations for a reliable unit that also offers good value?
I really need some help with working out how much solar panels would be needed to support the Watersnake at WOT to avoid draining the batteries please
https://www.polkaudio.com/en-us/product/car-and-marine-speakers/db1242-svc/112444.html
And two of the dual-core modules for mains and subs
https://www.aliexpress.com/item/100....order_list.order_list_main.10.77481802zj2OBh
These amps will run from the 48v LiFePO4 bank, but they are still to be acquired and may be a while yet, as the new boat powertrain will be funded from the sale of the large trailer once the hulls are permanently moored. At that time I will splurge on a decent bank and charging
For now, the powertrain for the beachcat will be the 65lbs 12v marine trolling motor and 120AH AGM already acquired over a year ago and kept new in storage
SWNG 65/54 (SHADOW MK II)
https://cdn.shopify.com/s/files/1/0551/9733/5740/files/Watersnake-Shadow-MK-II-Manual-2018.pdf
This can only supply 12v to the amps, but I have that 12-26v up stepper that I can use in the meantime. These things are cheap, so I might get a 12-48v up stepper too
Will use the 54lbs motor to sort out the power requirements for the craft and see how much more power do I need to get that 6 knot cruise speed (mackerel trolling speed). My proposed 48v powertrain is only dual 2.5kw BLDC motors and may not reach the target speed. There are other considerations like prop dia and pitch as well as motor KV rating too
Smaller props and high speed motors are good for better top speed but take longer to accelerate. I will be able to work out the type of prop and RPM that suits the hulls after running the 65lb Watersnake for a while and swapping out props on that. I may end up building my own thrusters using motors and custom props. The newer toroidal props would be safer around swimmers, and it's likely that I will need a larger prop on a lower KV motor for displacement speeds
I really want to push all the project subs during testing phase using the mobile bench at the boat ramp car park. My 1000/1 JL amp developed issues a while back and this thing is half my age and has had a very tough life. I have always felt that the amp felt knee capped. This is due to its poor dynamic ability. I need a class d true kw class mono amp that is 1R stable as the gorrila amp in the car to drive my 12W7 and any subs getting tested at the ramp. This prolly means an amp with a true 2kw dynamic ability by my reasoning. The JL amp just doesnt have that burst legs
Recommendations for a reliable unit that also offers good value?
I really need some help with working out how much solar panels would be needed to support the Watersnake at WOT to avoid draining the batteries please
Last edited:
Am I working this out correctly? 50A max draw and 12v supply, so 600w? If this is correct, I think maybe add a 300w panel at a time until the load on the battery disappears on a good day. Is there a better way to sort this out?
I don't quite understand the panels. Are they modular, can they be run in series to get 48v and parallel to get higher current? If I can work like this then I may be able to run 4x 10v 300w panels in parallel to get max potential on the best day of 1200w and later run them in series for the 48v system upgrade
The draw would be a combination of propulsion and audio. If I am at WOT then the system is likely to be at WOT too, or to be accurate, running the loudest comfy SPL just like in a car while crossing the bay
I seriously intend to implement some square metres in a kite to take advantage of the wind, so let's see if the 120AH AGM battery in hand can last a day running the audio first. Lol the amps are rated 2400w between the two modules, but I doubt I will need that for on board volume. The thrusters would be for in close work and dead calm days
Let's set a target date of the first day of summer for the boat naming/launch day for the beachcat
I don't quite understand the panels. Are they modular, can they be run in series to get 48v and parallel to get higher current? If I can work like this then I may be able to run 4x 10v 300w panels in parallel to get max potential on the best day of 1200w and later run them in series for the 48v system upgrade
The draw would be a combination of propulsion and audio. If I am at WOT then the system is likely to be at WOT too, or to be accurate, running the loudest comfy SPL just like in a car while crossing the bay
I seriously intend to implement some square metres in a kite to take advantage of the wind, so let's see if the 120AH AGM battery in hand can last a day running the audio first. Lol the amps are rated 2400w between the two modules, but I doubt I will need that for on board volume. The thrusters would be for in close work and dead calm days
Let's set a target date of the first day of summer for the boat naming/launch day for the beachcat
The smaller models have a " MAX.THURST(LB)" (can't spell thrust correctly..) equal to their amperage (a little too convenient), the SWNG 65/54 (SHADOW MK II) 65 would draw 65 amps.
Yes, though the Peukert effect will limit the amperage available from a 120AH AGM, and discharging below 50% will age your battery considerably, limiting it's potential storage capacity, further reducing the amperage available.
https://www.batterystuff.com/kb/tools/calculator-for-load-specific-run-time.html
Real world testing will be the best way to sort out what will actually occur with various wind and wave conditions.
The added wind loading of additional panels will help or hinder at various points of sail.
Yes, solar panels in series adds voltage, in parallel increases current.
In series, the total current is determined by the panel with the lowest current rating.