Is a sealed environment always better for speaker enclosures?

Specifically when dealing with smaller, less powerful speaker. I am aware that certain sub woofers require venting, but I don't know how important sealed boxes are for midrange and tweeter.

Question by Andale_The_Great   |  last reply


Is it ok to put 2 subwoofers in a single sealed enclosure? Answered

Is it ok to put 2 subwoofers (wired in series) in a single sealed enclosure or should they be seperated? My worry is that the single sealed enclosure may cause too much pressure rather than adding more pop to the sound.

Question by Andale_The_Great   |  last reply


Needle valve on the cheap?

I need a needle valve or similar to adjust some pressure with more or less precision. Problems I am facing with commercial solutions at the moment: Needs to withstand about 300psi max pressure, must survive contionous exposure to concentrated ammonia vapour. I already wasted too much money on stainless steel valves claiming to be chemical proof and capable of 6000psi only to find out they use seals that turn to goo in the ammonia vapour and fail. And since the stuff is not really healthy, not easy to get, I would prefer something safer. Real problem is also that the thing should be able to allow for good flow rates when opened fully. Modes of operation: During the active cycle ammonia vapour needs to pass through an opening as big as possible while after that the flow must be shut off. The reverse cycle needs to be adjustable from closed to fully open with great detail to control the flow rate. Current ways to compensate: With a ball valves and extra piping I could seperate the two cycles so I won't have to bother with tiny openings but I would prefer to use only a single connection. With a bypass around the needle valve this could be accomplished better but still looks ugly. Materials out of the question: Copper, brass, normal seals based on rubber, nitrile or similar. Questions: I know fully sealed in.line valves exist for LPG system and similar. Are any of these magnetic valves available for the use with ammonia? And if so: Can they be operated with a neodymium magnet instead of the coil? Even stainless steel valves rated for chemical use and high pressure fail quickly on the seals. Is there anything available that does not use soft seals but for example aluminium instead? Thinking spray pump here... One way ball valve systems like used in simple spray pumps are a great thing. With some aluminium tubing I was able to make a simple valve that with some more attention to detail might even work. But of course there no other way of moving the ball then to use a magnet and with sufficient back pressure even neodymium ones fail to get the ball in the open position and keep it there. Now getting this combine with a needle... If, instead of the ball, a magnet in a teflon shell is used on a spindle I could spin a magnet around the outside to turn the valve with great precision. Has anyone already designed such a thing or would I have to start from scratch here?

Question by Downunder35m   |  last reply


How do I take apart the Onda vx575HD?, I need to access the screen. Answered

Hi, The item has no obvious screws or catches, the ports stick into the side part of the rear frame and there is no other way of internal access other than removing the body. How would I go about remove the rear parts so as to access the screen? For pictures just type in 'onda vx575' on google images. http://www.google.co.uk/images?hl=en&source;=imghp&biw;=1366&bih;=677&q;=onda+vx575&gbv;=2&aq;=f&aqi;=&aql;=&oq;=&gs;_rfai= It's not broken so I'm not going to talk to the manufacturer and there is no warranty anyway. I just have an instructable in mind. Thanks in advance Jack

Question by jackh94   |  last reply


will concrete cure when in a sealed container? Answered

If the container is completely full of concrete, or possibly has a small air space?

Question by theRIAA   |  last reply


How to charge multiple batteries in a strange configuration?

Hi all,  Basically I'm planning on making an electric motorbike within the next year or so and need to know how to charge the batteries. I'm planning to have 8 batteries altogether, 4 batteries connected in series, then the 2 sets of 4 connected in parallel to up the capacity. How would I go about charging this configuration? The batteries are going to be high capacity, deep cycle sealed lead acid batteries. Cheers, - Will

Question by xXAfterBiteXx   |  last reply


Sunbeam Foodsaver Vac430 won't seal bags

It's seems to work without any packaging and sealer is hot but as soon as I try to seal a bag it won't seal but pump sounds like it is working

Question by PamandGlynO   |  last reply


anyone knows how to build a heat seal lidding machine for sealing plastic container and lidding film?..

It has been quite some time I have been searching around in the internet, web pages, articles, instructables, make magazine or any other DIY thread and forums for a guideline or instruction on how can we built ourselves a heat seal lidding machine which can be used to seal a lidding film to a plastic container which is widely used by the food packaging company. There are a lot automated and sophisticated commercial machine being manufactured by many companies which priced at 10, 20, and even hundreds of thousands dollars. Even for a simple small mini hand operated machine cost up to 1,000 dollars.. I believe I am not the only one who are searching an instruction to DIY this machine, at least for own usage at home for small quantity operation. It is great if there are someone who brilliant, an inventor who can guide us in building this kind of machine. So far that i search, i found out that the closest article about heat seal is an instructable article "how to make a heat sealer" by klee27x. Hope that there is someone out there who can gave us light, either theoratically or a real deal about it.

Question by izhrin   |  last reply


Automatic Bottle Filler, Seal and Capper and Label Applicator.?

HELP!!! OK, I have put together a awesome new group of liquid based products for a variety of uses (being vague bc it's to much to go over now). But before my investor group will commit to stage 3 of funding (stage one was a small infusion for the chemistry and product development, and stage 2 is on my own dime). Now I have 30 days to come up with plans and a protoype assembly line to produce the first 500K in units...it needs to be fully automatic, not semi-automatic...at least for each individual process. I have researched the net and there are alot of semi-auto systems i can fully automate, and the big boy systems are just out of my reach until I get stage 3 funding...i have to produce a min of this much product in an effort to get it on the shelves of the clients we have setup. I need to fill round bottles (2.5 and 4 oz and 12oz), fill flat sided quarts and gallons, and hopefully at some point round and flat sided 3,5,and7 gallon buckets. i know that this can be one machine with different run setups or 3-4 different similar systems. then I need a sealer, basically applies the pressure sensitive seal then heats it and seals it form spilling, tampering etc. then a separate system that screws the cap on finally and importantly applies either the peel and stick pressure sensitive pre-printed labels, or heat transfer label or silk screening... OK before anyone says a thing...i know its very complex, I know it's gonna cost some money, but I do know it can be done DIY style... so your thoughts, input, links to similar parts and pieces or ideas, etc...

Question by IdeaVault   |  last reply



how do i seal and coat the inside of my microwave?

The microwave interior (where you put the food) rusted out in one corner i need to fill it (with what ) and coat it to make it look good and be properly sealed but with what do i coat it? so far everything i have used has caught on fire. thank you   

Question by fixitnotbroken   |  last reply



My stubborn Sealed lead acid battery refuses to charge!?

Just the day before it was working perfectly fine! And all of the sudden it doesn't! Its about 10 Amps and i was planning to use it but know it wont charge. Its about 2 times wider than those batteries that alarms use(look in that big box in the wall there is a lead acid battery in there) in my case i had 2. Its kinda like the one in the picture,Except a bit taller

Question by ReCreate   |  last reply


If I tried to strangle a seal, would it's blood eventually become alcoholic? Answered

I read that when low on Oxygen, diving mammals switch to fermentation instead of respiration, which would make their blood alcoholic. At least, this is what I think.

Question by hydrnium.h2   |  last reply


How can I make a cheap foam for sealing spaces - that's not edible by bugs :-)?

That's basically it - a cheap bulk foam filler. Thanx

Question by Baatjes   |  last reply


what can I do with 12V sealed lead acid battery's?

If got a couple of 12V sealed lead acid batteries. What can I do with them? Perhaps A fun Tech project thing or something? Because they are perfectly fine and I got them for free. I'm not planning on throwing them out, but I don't know what to do with them either. So can anyone help me out?

Question by theexternaldisk   |  last reply


I want to combine 2 - 12 volt 12 amp hour sealed lead acid battery's with 2 - 12 volt 50 sealed lead acid battery's

I want to extend my driving distance I know if I got with 4 - 12 volt 50 sealed lead acid battery's it will take 14 hours to charge the set of 4 and I do not know even if I bought a new 2 amp hour charger that it the charger will last very long being run for that long of time I wan to combine 2 - 12 volt 12 amp hour sealed lead acid battery's with 2 - 12 volt 50 sealed lead acid battery's is this a safe thing to do will the higher amp lead acid battery's do damage to the lesser one's ? this set up is for a E-bike which takes just under 25 amp hour draw I've seen the draw get into the first bar of red but only in winter when it's rile cold say about - 47 Celsius

Question by Cleasonsook   |  last reply


How difficult is it to replace the seals on a pump action BB rifle about 20 yrs old ?

My gram-pa gave it to me at 15 and worked great! Now the air doesn't compress or hold when pumped, grrr. It's a Daisy I think.

Question by JulieS257   |  last reply


How to magnetize new refrigerator door gasket????

Refrigerator door gasket came unmagnetized. Very expensive, and, royal frustration thus far. Got the thing installed okay, but there is no 'seal'. Supposedly, according to Whirlpool, they don't need magnets in the fridge door gaskets to seal.....(Yeah, right) Any way to make a gouzer? Figured I could depend on help here. If I had enough magnets, I'd make my own. Also, why are the gaskets on the door?

Question by littleangels   |  last reply


12v to 12v lead acid charger? Answered

Is there any way to make or buy a 12v battery charge another 12v battery?

Question by Daniel Deacon   |  last reply


Low Power pc?

Right for some time now I have been thinking of building a computer that is low power 20w max needs to have some processing power preferable duel core i have been looking at 'intel D510MO' link to spec > http://www.ebuyer.com/product/191127 What i would like is for someone to advise me on what to buy to keep the power low (20w or less) and the performance high at a fairly low price

Question by Daniel Deacon   |  last reply


How to steam open an envelope?

Any suggestions on how to steam open a sticky sealed envelope?

Question by jshhndsd91   |  last reply


Where is the manuel tire pump vaccumn sealer that used to be on this site?

The manuel floor tire pump for bikes etc was shown to be altered to suck air out instead of forcing air in. It could be used to seal jarsof dry seeds etc. I could not download it the other day and now I cqn't find it.

Question by zenniagirl   |  last reply


I have a leak between a PVC pipe and a fitting, whats a good glue to seal it with. Answered

I tried plumbers goop but it only get a few shots before the seal breaks. The leak is between a modified bushing in which I grinded the lip off and a 11/2 in pipe. Its for a piston valve air gun.

Question by imthatguy1125   |  last reply


What voltage can heat gauge 24 nichrome wire 30 cm long successfully? Am building a polythene sealing machine

Am building a polythene sealing machine using nichrome wire, I use 9v battery but is not heating. What voltage should I used and can I use ac or dc

Question by Gopep   |  last reply


how do i put 2 gloves together and make the seal between the two wateright? Answered

I know this is a strange question but i am working on a project and i need to fill a glove with mineral oil and then put another glove inside of that glove so the oil surrounds the hand. the problem i am having with this is the seal i am trying to make it with hot glue by putting the 2 gloves around a cup then putting a ring of hot glue around the inner glove then folding down the lower glove. my first attempt failed and my second has multiple holes that are hard to patch. any ideas on how to do this easily? i only have four gloves 2 for practice and 2 for the prototype which will enter a competition on the 26th. PS: i am kinda in a hurry i have until the 23rd to get this project done.

Question by harry88   |  last reply


repair a tire pump? Answered

Hand pump offers little to no resistance when pumping. loss of seal inside the pump cylinder.

Question by    |  last reply


Can a marble size glass bead be made and vacuum sealed with Hg Liquid Mercury in it? Answered

I'm in need of this one item if it is possible to produce according to goverment documentation discovered after world war 2 and from old experiments done by the captured scientist this is possible was originally intended to be the core of stage 2 anti gravity machine 1 sphear was found and the documents later backed up to be fact that hitler was ingaging in experimental space technology during world war 2 when a U-Boat was discovered with Hg Mercury and many more items relating to the project known as the bell do to the shape of the gravity machine i been researching this since i was extreamly young and recently found last piece i needed to my alchemic equation and i have begun working on a free energy reactor but i need a Marble Size Hollow Glass Bead Filled with Hg Liquid Mercury to be the core for the prototype will pay anyone to make the Glass Bead filled with Hg Liquid Mercury and Vacuum Sealed  for me because i am limmited as to what i can an can not have in the hospital also huge credit will be given to those who help when published It's finally Published here on instructables.com .

Question by maskofdarkness22   |  last reply


How is the piston on an old manual vac. pump repacked using leather sealant(packing) for which it was designed?

I have several antique manual piston vacuum pumps all of which need the pistons "repacked" with leather gaskets. The leather sealing gasket is specific for this type of antique pump and allows the lubricated piston and leather sealant to provide an airtight seal between the piston and the internal cylinder walls into which it inserts. The piston rod is pushed inward by way of handle which is attached to the piston rod in the cylinder. On manually pulling the handle or lever outward, and thus the piston, air is evacuated from a bell jar via tubing and a valve, the bell jar resting on a round metal plate or stage (sealed with vacuum grease) to which the tubung communicates and subsequently communicates with the pump. Upon pushing the pump lever inward (and thus the piston), air pulled into the pump cylinder on the evacuation stroke is vented to the exterior by means of a one way communication between the fore side of the piston and the aft side of the piston and to the atmosphere by way of a hole in the closed end of the piston cylinder. The cycle is repeated as necessary. Does anyone know how to repack the pistons with the required leather seals, or have a source for the leather seals, or know of a craftsman who knows how to accomplish repacking of these historical pumps (antique scientific instruments). Thank you for your attention to this matter.

Question by pm7289   |  last reply


How to make a charger for a 4 volt 4.5 ah sla battery? Answered

I have a 4 volt 4.5 ah sealed lead acid battery out of a cordless phone battery backup thing and I have no way to charge it. Does anyone know how to make a charger for it or even at what voltage and amps to charge it at? Thanks.

Question by JasonYMN   |  last reply


What can I do with these???

Hello again, I want to bug you guys again, if you remember, I just fixed these JVC speakers as the seals were gone on the plexiglass. Now that's fixed, I've been noticing that when I play almost any song past volume 20-22 I can really notice a lot of turbulent noise from the tubes, and it's not the seals this time, they seem to be holding out. It just sounds punchy and the noise coming from the tubes kind of ruins the fact that I fixed the seals already, theres 4 screws around where the tube goes into the subwoofer chamber, but I tried taking it out, but it still wouldn't come off even though the 4 screws were removed. Does anyone have suggestions on how I could make these speakers sound better??

Topic by Punkguyta   |  last reply


How do you build a mini ecosystem? Answered

It will be built inside a container that's about 30cm by 30cm by 20cm. Once finished, it will be sealed with a lid forever. It has to be sustainable, viable, and reasonable.

Question by    |  last reply


can you make expanding foam yourself?

You can buy it in cans and i've seen 2 chemicals mixed to make it. can it be homemade with easy to get materials?

Question by jvherbin   |  last reply



Dissolving Epoxy Answered

I have a project where I have an antique electronic part that is sealed with epoxy. Is there any way of dissolving the epoxy in order to view the original parts? This is so I can construct a replacement part.?

Question by Foxtrot70   |  last reply


is there a foodsafe and heat resistant adheisive?

I am joining copper tube to a stainless steel pot lid, i have joined them but want to make an airtight seal. is there an adheisive i can use that will be heat resistant and not react with alcohol?

Question by the rowdyboy   |  last reply


What size of diode do I need to connect my solar panels up to two sealed 12V batteries connected in series?

I'm not worried about over charge for they will have constant drain on them.

Question by SYMMETRY   |  last reply


What effects does running a gasoline engine with propane have? Answered

I know that propane will run a gasoline engine, but besides the hoses and seals drying out is there any massive loss in output or any other kind of wear on the inner workings?

Question by luckymoonboy1   |  last reply


How could I charge two Sealed Lead-Acid batteries at the same time and power 2 differnet devices? Answered

Could somebody please help me? I cant find a way too charge 2 SLA's at the same time and run 2 seperate devices and make it so I can power one device one one battery and another device powered by the other battery. There some some writing on the battery casing  But I don't really understand but it reads: ______Constant Voltage Charge_______ I        Voltage Regulation                                I I           Cycle Use           14.4 - 14.7V            I I        Standby use           13 .15 - 13.8V        I I    Max charging current                  1.2A       I _________________________________ Any help would be appreciated. Thanks in advance.

Question by CyclonicNinja   |  last reply


Valve that shuts off once a set pressure is reached?

For something I am in the process of designing, I need a valve that can be connected to a high pressure source and will allow the gas from the high pressure side to to flow into a sealed container on the other side until a pre-set pressure is reached. It should then shut off. The system used to do this should also be able to handle a very high pressure spike (possibly even the type of compressed pressure wave generated during a super-sonic combustion / detonation) on the sealed container side. If you can provide a diagram or the name of a type of valve or even just a description of how this could be done it would be appreciated. No computer controlled stuff please. ##################### The answer I have discovered is to use a regular diaphragm-type pressure regulator. ######################

Question by Jaycub   |  last reply


if you added a second speaker instead of a port in the enclosure, what effect would that have on the sound?

I know that if you have a ported enclosure on a subwoofer its louder and if its sealed its more precise,  but what would happen if you put a second subwoofer in the enclosure instead of a port? what would the effect be? im just curious.

Question by tokymaru   |  last reply


How do I revive dead lead-acid batteries? Answered

I have one that's been dead for several months. It's 12v, 4AH. It's sealed lead-acid rechargable battery, any ideas on how to revive it? Also, how would you charge this kind of battery?

Question by 1up   |  last reply


How do I repair or replace the accessory vacuum hose on a Food Saver Model V3820?

The accessory vacuum hose stopped drawing a vacuum.  The motor runs. The main part of the machine still vacuums and seals as it is supposed to do.  The reel works and the hose does not seem to be damaged in any way. Everything else seems to work as it should.

Question by james.mullis.165   |  last reply


Are these power supplies good?

The cheap bare metal power supplies from ebay or other sides have been reviewed many times on youtube and people have found that they are actually decent. But I cannot find any reviews of the sealed plastic kind of power supplies. The "bare metal" ones I am talking about look like this, and the "sealed plastic" ones look like this and this. Edit: None of your replies answer my question. I am not asking which one I should choose, I am asking if the plastic ones are just as decent as the metal ones. There are a few reviews of the metal ones, and people have found that they are actually quite decent. Here are some: https://www.youtube.com/watch?v=vwFrP7uK5lM https://www.youtube.com/watch?v=71NWT5vrbk8 But I cannot find any reviews of the plastic ones, so I don't know if they are just as good. I am asking if anyone has gotten any of these and made a review with some tests, or knows of a review of these.

Question by poiihy   |  last reply


Two 4" Drivers in one enclosure?

I want  a very deep Bass as i am getting in my logitech z103...(image attached) I am plannin' to build a sealed 10" cube outta 0.5" thick Plywood and put in em two 4" subwoofer drivers. will i be getting the thing i want???? if not what should be the dimensions???? THnaks in advance!!!

Question by adarshnarsaria   |  last reply


DIY Plexiglass Window

Hey guys, time for another update of what I've been up to lately in my spare time. The other day I just finished a project, where I decided to take some scrap plexiglass and install it as a window in the top of my subwoofer, just like how more expensive pre-built subwoofer boxes have them. I tried to take pictures as I went along with it. Trust me, I may only have a handful of picture, but it took A LOT. Most of the hard work was chiseling the MDF board to fit a groove for the plexiglass to sit in and make a seal. P.S.: Chiseling MDF board is like chiseling cardboard, very easy to take too much out! Also, does anyone have any ideas as to HOW I could get some of the deeper scratches out of the plexiglass??? I'll be taking it apart to re-bevel the edge of the seal once I find the damn wood router, so when I do that I'd like to buff the plexiglass out a bit. Also, I think I own bragging rights for doing this.

Topic by Punkguyta   |  last reply


Need to pick a good 12v rechargeable battery for led camera lights?

I made some video camera lights out of 3 1w MR16 leds. Right now I have a sealed lead acid that works well but is 10 pounds. I need a alternative that will be more mobile and practical. I have considered taping into my cameras phantom power which provides 48v for a mic. 

Question by maxwelltub   |  last reply


Lawn mower blade hub.

I'm trying to figure out how to get the blade hub off of the bottom end of the crankshaft on my TroyBilt - Honda powered mower. There is no set screw that I can find, and it doesn't appear to be a thread off. There is a key, but I can find nothing that suggests how to get this thing off. I need to take it off so I can change the bottom crankshaft oil seal. This is a Honda GCV160 engine. Thanks for any input.

Topic by thebilger   |  last reply


how are fluid bearings made?

I was looking at fluid filled bearings and wanted to try and make one i just cant understand how they are filled and how they can rotate without leaking any ideas on how they are sealed?

Question by sharlston   |  last reply


can i turn a fridge freezer in to just a freezer?

I have and old vertical fridge freezer.( freezer compartment on top).  the seals have pretty much gone on the fridge part, so i am wondering if its possible to completely disable the cooling of the fridge part, while the freezer carries on working. i am assuming also that this will reduce the running cost of the unit if only the freezer5 cheers will

Question by agatornz   |  last reply