Im confused now, silicone or chemical metal to glue woofers/grills to baffle? Or do you mean, Glue woofers/grills to baffle with chemical metal, then seal around the woofer with silicone?
BJ
Woofer magnets to brace -> chemical metal
Woofer gasket to grill and baffle -> silicone (solvent free)
Thank you so much Saturnus, that helps a lot.....
my hole saws arived today and I'm hoping to have the tweeters by the end of this week so woofers to baffles is my job for next weekend.......
I shall order some black non corrosive silicone sealer to glue the woofers to the baffles so that if any squishes out from the behind the black grill that is inaccessible when I fix the woofers, it wont be too noticable......
My plan is to clamp the woofers by using small screws into the baffle to hold the woofers and grill in place while the silicone sets..... I have been wondering whether I should remove the screws once the silicone has set, or leave them in place for a bit of extra support but I dont want them to come loose and rattle around in the box once it is sealed shut. I may fix the screws in place by ensuring that I smear sealant arond the screw heads when sealing the woofer edges......
Oh, decisions, decisions........
BJ
my hole saws arived today and I'm hoping to have the tweeters by the end of this week so woofers to baffles is my job for next weekend.......
I shall order some black non corrosive silicone sealer to glue the woofers to the baffles so that if any squishes out from the behind the black grill that is inaccessible when I fix the woofers, it wont be too noticable......
My plan is to clamp the woofers by using small screws into the baffle to hold the woofers and grill in place while the silicone sets..... I have been wondering whether I should remove the screws once the silicone has set, or leave them in place for a bit of extra support but I dont want them to come loose and rattle around in the box once it is sealed shut. I may fix the screws in place by ensuring that I smear sealant arond the screw heads when sealing the woofer edges......
Oh, decisions, decisions........
BJ
I dont know, if the sound differs to a normal boominator build, since I never heard one...
but I also thought that especially stereo sound might sound weird, so I at least used a extra thick piece of wood to seperate the two cabinets. In general im quite happy with the sound- only when you turn volume to the max (while hanging on a strong enough 13,5v external power supply) , the sound starts getting weird (cant describe it more accurate). however, I am not sure if that is due to acoustical properties of the cabinet, or the amp behaviour, or maybe the volume itselve... How is it with the regular boominator??
Yes I use acetic acid-free "neutral cure" clear GE Silicone II. Its around everywhere here and pretty cheap.
Yes I got my piezos from Piezo Source, they are the only company that makes the original models and they're only a few towns away so shipping was cheap! (although they're pretty feather light)
My epoxy is pretty viscous and doesn't run so it would work. And there is flexible-curing epoxy as well. Saturnus you use only silicone to stick together the baffle assembly and remove the screws? Does silicone work as a glue that well? It would be annoying to use screws and ugly on the front too, but I would think it makes the box more secure.
Yes I got my piezos from Piezo Source, they are the only company that makes the original models and they're only a few towns away so shipping was cheap!
(although they're pretty feather light)My epoxy is pretty viscous and doesn't run so it would work. And there is flexible-curing epoxy as well. Saturnus you use only silicone to stick together the baffle assembly and remove the screws? Does silicone work as a glue that well? It would be annoying to use screws and ugly on the front too, but I would think it makes the box more secure.
Hello,
I'm building a bicycle soundsystem for the critiaclmass ride based on boominator. Already have a working AMP6 and am currently using it with two small speakers that fit on a bike rack.
Me and my mates decided to build our own speakers, and since none of us knows much about building them, i hope i'll get some help from you guys.
The idea is to cut the original boominator in half - one of the box will be slightly larger, containing the battery and amp (we are also planning to include a preamp for mic). Could you please take a quick look at my sketchup and suggest changes? I had to move the bass port and am a little worried about the opening top - the longterm plan is distributed sound (when more system are built, we'll transmit music on a radio frequency, or maybe wifi), so i want good access to the compartment to add new stuff.
https://dl.dropbox.com/u/3679557/soundsystem/main speakrer.png
https://dl.dropbox.com/u/3679557/soundsystem/main speakrer.skp
https://dl.dropbox.com/u/3679557/soundsystem/little speaker.skp
How do you feel about this?
I'm building a bicycle soundsystem for the critiaclmass ride based on boominator. Already have a working AMP6 and am currently using it with two small speakers that fit on a bike rack.
Me and my mates decided to build our own speakers, and since none of us knows much about building them, i hope i'll get some help from you guys.
The idea is to cut the original boominator in half - one of the box will be slightly larger, containing the battery and amp (we are also planning to include a preamp for mic). Could you please take a quick look at my sketchup and suggest changes? I had to move the bass port and am a little worried about the opening top - the longterm plan is distributed sound (when more system are built, we'll transmit music on a radio frequency, or maybe wifi), so i want good access to the compartment to add new stuff.
https://dl.dropbox.com/u/3679557/soundsystem/main speakrer.png
https://dl.dropbox.com/u/3679557/soundsystem/main speakrer.skp
https://dl.dropbox.com/u/3679557/soundsystem/little speaker.skp
How do you feel about this?
The idea is called a halfinator, and it has been completely covered in this thread, look through the last 100 pages, and you'll find everything you need.. If you still need some info, read it again
The basics are making a solid brace to isolate the channels, and increase the height of the chambers to compensate.
The idea is called a halfinator, and it has been completely covered in this thread, look through the last 100 pages, and you'll find everything you need.. If you still need some info, read it again
Well, not really, i'm building two boxes, each for one channel - front and back rack, so no solid brace is required; and if playing form only one box, i'll just set my iphone output to mono.
*The smallest size box that it takes to replicate the lively dynamics of a concert is about 0.7 cu ft per woofer.
*You have an excellent example of the modern approach that solves the problem of thin woofer coils high inductance needing high value RC that would sound awful, but fixed by putting the woofer coils in parallel, resulting in half inductance, half the RC, double the audio quality of the crossover, at the expense of double the load. That's the modern approach and works well with amplifiers that are 4 ohm friendly. Electronically, it relocates compromise out of the speaker and into the amplifier. That's good because 4 ohm friendly amplifiers are widely available but really high end woofers are in short supply (much easier to parallel two ordinary woofers to achieve high end).
*And, you've used Piezos, which have a wonderful open sound at the expense of tone and the tone is not a problem with portable players (especially RockBox) that all have EQ's, so the easily doable end result can be really good sounding (sort of like electrostatic, except more powerful) and although quiet playback might not be as clean as a well padded dome tweeter, loud playback is a LOT more clean than a dome tweet because a Piezo does not strain easily (it does not choke).
*There's a lot of support and examples that make Boominator look especially doable, and that's worth a lot.
*And, you've got an outdoor tuned double-woofer, double-channel portable speaker with huge lively blockbuster dynamics, which increases the fun factor to about 400%.
KUDOS!!!
Electronic upgrade?
However, there's a couple of enhancements that I'd like to see, such as amplifiers able to withstand a range of 8v~24v (range is from run-flat battery to charger peak voltage), and also a consideration of bi-amp, to run tweeters on their own amplifier so that any clipping cannot occur at the treble (especially important as the battery runs down). I believe that these two steps would really help.
I wonder if a miniature buck-boost card + miniature amplifier can efficiently run the tweeters with never-clip performance?
Documentation upgrade?
Diyaudio.com has "forever edit" at post 1, so you can put updates, FAQ, Q&A, links to schematics all in a unified location. Although intrAthread links misfire, you can mention the post number. All other links work, including links to Attachments both intrAthread and everywhere.
For an example, check out the Circlophone Build Thread where Post #1 has been edited many many many times, usually in response to a question, a development or for quality control. The first draft wasn't so pretty, but dividing it up into categories solved the appearance difficulty. Usefulness developed over time as answers to questions and solutions collected in post#1. The last major edit was to "cut the chat" to reduce the word count to half while retaining most of the meaning, and even that edit was in response to a question although that particular question was reading comprehension vs long text rather than electronic; but, that was appreciable and useful too, since cutting the chaff made the project even better and easier. Maybe the one non-electronic question was the most useful of all.
Anyway, consider at least some sort of link, drawing, schematic, vendor and post# collection at Post1 to point the way.
To avoid the intrAthread link to post# misfire trouble, you could start a new thread "Boominator Documentation" so that all the links will work and you won't have to re-type a bunch (just link instead). In this way, all content, including experimental, is posted on the big thread, but only proofed content (and working build results) is linked to the little thread's post#1. Then you wouldn't have to answer the same question 700,000 times.
Lastly, link to your documentation thread can be put into your Signature line so that the documentation can be found.
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The most significant problem is that there are no chips or chipset available that can do precisely what it required for a universal amp.
In order of importance.
1) 4 channels.
This is due to the design being prepared for the use of an active crossover, analog or digital, particularly when better drivers are used. And specifically when a normal tweeter is used.
Not a problem. Just use more chips if needed. TAA4100A is four channels already.
2) 10V to 30V tolerance.
This one is the most tricky one. Running 2 batteries in series while charging means that up to 29V is supplied. Almost all single chip solutions have a hard limit overvoltage protection of 25V-27V even if the chips nominal absolute maximum rating is 30V. If the overvoltage protection could be removed there would be quite a few chips that would do the job.
I am not aware of any other chips than TAA4100A, TDA7498, and TK2050 chipsets that fulfill this requirement.
3) 3.2 Ohm load capability
Another tricky one as it's technically possible for most chips but only if they run in PBTL, so that means one channel per chip which naturally puts a limit to how small you can build the amp. Although you can probably easily get away with running the tweeter channels on a single chip as the each will only have under half of the output current of a woofer channel.
The TAA4100A is 3.2 Ohm load capable at 29V into the required 3 "channels".
4) Minimal board size
The absolute maximum physical size including casing and/or heatsink is 66x58mm width and height. Length can be made longer if needed with few modifications to the design but in the original design 150mm is the length between the venting holes.
An amp9b in a Hammond 1590N1FL case is 66x40x149mm including the mounting flanges, so there's room to attach an additional heat sink on the "bottom" of maximum 66x121x18mm if needed (a Wakefield 559 series multi-finned heat sink works well here. It's 61x117x12mm and has 6 mounting screw holes).
5) Minimal power consumption
TAA4100A is 220mA.
TK2050 chipset with 3 output drivers is 205mA to 400mA depending on actual output driver.
TDA is 120mA with 3 chips.
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I am having a bit of an issue. I ran 12 gauge wire for the Tripath to lifepo4 with gold plated 4mm bullet connectors, but I have no on and off switch wired.
I have a switch that is rated at 120v@5A (so 400w+) however I am slightly worried about the resistance and voltage loss from heat by putting a switch into the circuit....am I being really stupid? Are we talking about like 0.05w power loss from replacing 1cm of 12gauge wire with a small switch? Anyways any advice would be grateful, or how anyone else wired their power switch. Thank you in advance.
I have a switch that is rated at 120v@5A (so 400w+) however I am slightly worried about the resistance and voltage loss from heat by putting a switch into the circuit....am I being really stupid? Are we talking about like 0.05w power loss from replacing 1cm of 12gauge wire with a small switch? Anyways any advice would be grateful, or how anyone else wired their power switch. Thank you in advance.
Yeah. It's probably much less. Typical initial contact resistance is about 10mOhm which is around 0.0015W but resistance drops far lower than that after initial contact.
These are the ideal resistors for original ksn's right?
20 Pcs 1W 33 Ohm 33ohm 5 Carbon Film Fixed Resistor | eBay
I also found 1/2W 33ohm.
20 Pcs 1W 33 Ohm 33ohm 5 Carbon Film Fixed Resistor | eBay
I also found 1/2W 33ohm.
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Actually those are carbon film not carbon composition. You need to search for that exact word "carbon composition".
For example RC1330KB Kamaya | Mouser
For example RC1330KB Kamaya | Mouser
Reconnoiter for unbreakable parts.
This is really hard. I checked the TDA7492 setup for 50w+50w tolerance, and it had a voltage range of 10v to 26v. But no, that won't do. Normal "12v" batteries go right down to 9v under load and "bump" 8v on bass beat, which this amplifier can't play because it already fainted at 10v. Oops!
Question:
Will this work out with the ~18vdc cordless power tool battery packs?
The trick seems to be to choose an amplifier that cuts off at the make/break damage or not voltage of a given battery. But the high voltage range needs to be within the capacity of both using and withstanding an excellent solar panel, and arrays of that can output a rather stiff 24vdc in brightest sun.
I tried holding this back to 15vdc (max car alternator like voltage for TA2020, TA2021 which are car amplifiers), with a rather massive zener and ballast resistor array as a voltage limit; however, the solar panel was much too good and burnt up my limiter in minutes and with a LOT of smoke. Chopper style efficient limiter like the CMP charger is only useful when the amplifier is off, because choppers create PWM pulse signals on the power line (he say "pop, pop, pop, pop"). Impasse for the TA2020, TA2021 so far, unless I use much weaker solar that is only capable of extending runtime rather than strong enough for full charge while run.
But, at first glance, the TDA, plus cordless tool battery pack, plus at least 3 of the 5w solar panels (each with its own schottky), looks as if it may maintain the battery somewhere in the range of 15v~20v in good sunlight. It looks like neither minimum nor maximum range causes any breakage. I don't see any problems. Do you see any problems?
Treble question:
What amplifier do you prefer for tweeter amp treble quality? Given that the tweeter has a series capacitor, the load seen by the amplifier is so very light that it is within the capacity of some headphone amplifiers. If this is possible, then the 8khz "shushy" or piezo lisp can be leveled so easily by installing an additional tiny size RC at the feedback-shunt area to boost 16khz up level with the 8khz of the piezo. The end result of that is the big theatrical everywhere open sound imaging of an electrostatic, but with the rather large exceptions of pricetag and weatherproofing, which are easier with piezo. I just don't quite know what cute little hi-fi amplifier to use for tweeter amp and also meet the requirements of unbreakable operating voltage range.
This is really hard. I checked the TDA7492 setup for 50w+50w tolerance, and it had a voltage range of 10v to 26v. But no, that won't do. Normal "12v" batteries go right down to 9v under load and "bump" 8v on bass beat, which this amplifier can't play because it already fainted at 10v. Oops!
Question:
Will this work out with the ~18vdc cordless power tool battery packs?
The trick seems to be to choose an amplifier that cuts off at the make/break damage or not voltage of a given battery. But the high voltage range needs to be within the capacity of both using and withstanding an excellent solar panel, and arrays of that can output a rather stiff 24vdc in brightest sun.
I tried holding this back to 15vdc (max car alternator like voltage for TA2020, TA2021 which are car amplifiers), with a rather massive zener and ballast resistor array as a voltage limit; however, the solar panel was much too good and burnt up my limiter in minutes and with a LOT of smoke. Chopper style efficient limiter like the CMP charger is only useful when the amplifier is off, because choppers create PWM pulse signals on the power line (he say "pop, pop, pop, pop"). Impasse for the TA2020, TA2021 so far, unless I use much weaker solar that is only capable of extending runtime rather than strong enough for full charge while run.
But, at first glance, the TDA, plus cordless tool battery pack, plus at least 3 of the 5w solar panels (each with its own schottky), looks as if it may maintain the battery somewhere in the range of 15v~20v in good sunlight. It looks like neither minimum nor maximum range causes any breakage. I don't see any problems. Do you see any problems?
Treble question:
What amplifier do you prefer for tweeter amp treble quality? Given that the tweeter has a series capacitor, the load seen by the amplifier is so very light that it is within the capacity of some headphone amplifiers. If this is possible, then the 8khz "shushy" or piezo lisp can be leveled so easily by installing an additional tiny size RC at the feedback-shunt area to boost 16khz up level with the 8khz of the piezo. The end result of that is the big theatrical everywhere open sound imaging of an electrostatic, but with the rather large exceptions of pricetag and weatherproofing, which are easier with piezo.
I just don't quite know what cute little hi-fi amplifier to use for tweeter amp and also meet the requirements of unbreakable operating voltage range.
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Compared to the discussions between danielwritesback and saturnus, my question is rather puny and shows my ignorance in electronics...... I want to have an input (3.5mm stereo jack socket) and a thruput (another 3.5mm stereo jack socket) so that I can link the same sound source with multiple boomboxes...... Is it as easy as wiring the two jack sockets in parallel so that the input signal can be "shared", or is there some other consideration that prevents it from being that easy? and if so, how should I wire it?
*BJ*
*BJ*