Making Speakers

[alex_kyuss]

Hi all, hope your all well. I am looking at making myself a pair of 2 x 18 inch subs and I was wondering if anyone could give me any good websites with designs and plans that can be used. After google search I haven't found much thats usfull

cheers all

[bruce]

After google search I haven't found much thats usfull

cheers all

 

Go to the search button above - NOT the google one, the one at the very top - and search for "speakerplans". All one word. It'll bring up half a dozen very relevant threads, most of which mention http://www.speakerplans.com/ ...

 

 

Moderation: Bruce beat two of us to this one - so I've removed them as they both said the same thing!

[Jivemaster]

The standard of woodworking needed is beyond many people, and the cabinet tuning takes time and effort. Oh! And a 2 x 18 is huge and heavy - say one and a half sheets of 19mm birch ply for the box and more for the reinforcing webs.

 

Keep one dimension small enough to pass through a single door, otherwise there may be places you cannot take them to!

[Modge]

Or the room they were built in :)

[paulears]

Modest woodworking skills are needed, but more important is machinery. A decent bench saw is critical, as is a router and biscuit jointer. The real problem with this kind of thing is that if you work out the costs of the components, it may simply not be worth it. 15" drivers are expensive, 18" ones even more so. Small things like speaker clamps and bolts - connector panels and handles are not that much, but still they mount up. If you dont have the power tools, you'll have to hire them - a hand saw is no good for cutting large panels (although some B&Q depots or similar will cut panels to size for you on their wall saws). The last thing is finish - proper paint finishes cost a lot of money, and take practice to apply, and carpet is just as tricky if you've not done it before. If you put castors on them to move them, that's another £60. All in all, you could buy some pretrty good ones, with a professional finish for not much more than the materials cost - and, they may actually sound better!

[Rich]

The standard of woodworking needed is beyond many people, and the cabinet tuning takes time and effort. !

 

I disagree. You can get all of the wood cut at B&Q for a small fee, and the woodwork is very simple for a 2X18" box (I presume we're talking BR).

 

As for the tuning, if you look at the recommended plans they are already tuned (providing you use the correct drivers). If you wish to tune your own designs then programs like Bassbox Pro and the free WinISD will do it all for you, plus give you graphs for frequency response, SPL and cone excursion to name a few.

 

I've built many BR designs using wood cut from B&Q and it's been dead easy. I have no previous cabinet making experience.

 

Check out the B&C website (www.bcspeakers.com), the Fane website (www.fane-acoustics.com) and the Selenium website (www.seleniumloudspeakers.com) for more plans.

 

The Selenium website contains lots of plans for horn loaded loudspeaker systems. These are much more difficult to build but will be much louder and have a better transient response at some frequencies. The plans also have detailed cut sheets. View the site in Portuguese to find the plans, they're not a available in English.

 

Also check out the Speakerplans forum - huge amount of speaker building knowledge on there.

 

Modest woodworking skills are needed, but more important is machinery. A decent bench saw is critical, as is a router and biscuit jointer. The real problem with this kind of thing is that if you work out the costs of the components, it may simply not be worth it. 15" drivers are expensive, 18" ones even more so. Small things like speaker clamps and bolts - connector panels and handles are not that much, but still they mount up. If you dont have the power tools, you'll have to hire them - a hand saw is no good for cutting large panels (although some B&Q depots or similar will cut panels to size for you on their wall saws). The last thing is finish - proper paint finishes cost a lot of money, and take practice to apply, and carpet is just as tricky if you've not done it before. If you put castors on them to move them, that's another £60. All in all, you could buy some pretrty good ones, with a professional finish for not much more than the materials cost - and, they may actually sound better!

 

A bench saw is not critical, nor is a biscuit jointer. I've built horn loaded mid tops with a circular saw, you need a good blade and a straight baton with some clamps. I agree cutting 8X4 sheets isn't easy with one, but B&Q will do the hard work for you. As for jointing, you can get away with a butt joint with screws and PVA.

 

Aldcroft Adhesives sell a water based, textured finish speaker paint. It is very inexpensive and easy to apply (17.50 will do you a pair of 2X18" cabs and it goes on with a roller). This paint is used by Void Acoustics on their products, and it is also used by a leading UK speaker manufacturer.

[paulears]

Hmm, ok - I defer to your better judgement. I found the opposite. A hand operated circular saw against a guide works as long as you keep it horizontal, and hard against the guide - something I must be bad at. The butt joints are fine, but I don't find them strong enough - well at least on MDF, they seem better on 18mm ply. My first efforts appeared great until somebody climbed up on on one and the top cracked at the joint with the vertical panel. PVA is strong, but the shear strength wasn't enough. My broken one was screwed and glued, but failed. I bought a biscuit jointer and these make much stronger joints.

 

The paint info is useful - thanks for that.

 

One good tip - get plenty of sash cramps - you can never have enough! (and extra hands come in very useful too)

[SteveB]

Alex,

 

There are also some useful links at speakerstore.

 

http://www.speakerstore.nl/index.php?l=nl&pg=5

 

Although the information about the finish is useful it doesn’t affect the performance very much. If you will be using the speakers yourself a lick of paint would work. It all depends how much you want or are able to spend on the appearance. The main thing is that the cabinet is physically solid and the joints are air tight. I wouldn’t go so far as Bill Fitzmaurice (he sells speaker plans) does and recommend filling large gaps with polyurethane glue, but if you can get a straight cut with a bread knife that is fine. Table saws and routers help but if you have the skill and are prepared to put the effort in it is possible to build speakers without them. You may be a cabinet maker and find all these comments a bit patronising, I don’t know. Only you know whether you have that ability. Another thing to consider is whether you have room to build a large cabinet. I have a large garage/workshop (complete with table saw and router) but some of the folks that post on the speakerplans forum use their kitchens and/or gardens.

 

Again, depending on your ability, it might be worth looking at winisd which will let you design your own cabinets. It isn’t too difficult to use. This thread at Harmony Central gives some pointers.

 

http://acapella.harmony-central.com/forums...d.php?t=1074743

 

Good luck,

 

Steve

[lightsource]

The standard of woodworking needed is beyond many people, and the cabinet tuning takes time and effort. !

 

I disagree. You can get all of the wood cut at B&Q for a small fee, and the woodwork is very simple for a 2X18" box (I presume we're talking BR).

 

 

A bench saw is not critical, nor is a biscuit jointer. I've built horn loaded mid tops with a circular saw, you need a good blade and a straight baton with some clamps. I agree cutting 8X4 sheets isn't easy with one, but B&Q will do the hard work for you. As for jointing, you can get away with a butt joint with screws and PVA.

 

 

 

Just remember that accurate wood cutting is probably one of the most important factors in enclosures. Remember a circ saw blade may be 3mm dia.

 

Therefore 2 pieces cut 'either side' of the line could cause a 6mm difference between 2 panels, which is really not good when final assembly starts.

 

Don't have a biscuit jointer (although I do have biscuits in the bread bin :) ) Whilst they may be useful in some cabinet designs, I have found no use for them in high power applications. I always use the pin and glue approach, although I do tend to add a couple of screws, just to keep everything together while the glue's drying.

[dbuckley]

One good tip - get plenty of sash cramps - you can never have enough! (and extra hands come in very useful too)

Aha! I hear Norm there... "you can never have too many clamps in a workshop"

 

Have a look at the Lab Subwoofer forum, and I mean look, don't post (leastways unless you've read every posting for the last few months and fully understand the local etiquette), and you will get a number of opinions about homemade subs, where to get plans from, and how well they work.

 

Edited to say - you have no idea how lucky you are to have those lovely saws at B&Q; the sheds here have nothing similar, so it is no fun getting an 8x4 (old money size, 1200 x 24500 for the young) home and then having to cut the thing up....

[paulears]

The comment on the saw width is pretty important - the wall saws at B&Q are great - IF they are used by skilled staff. The important thing for them is safety - that appears the focus of their training. asking for exactly 1045mm is tricky. Even if they can deal with mm (not certain in some stores) They often ignor the machine engraved measures and do it with a tape - and sometimes from the wrong side, so the saw blade width error gets included. The horizontal guide in my local store has saw cuts in the ali - where they started to saw through the guide! - how I can figure!

 

The other thing is that some of their ply has quite a few voids, making finish more trouble.

[SteveB]

Just a general comment not specifically aimed at the original poster, but picking up on the ‘oops one panel is 6mm less than the other’.

 

First off don’t panic. One comment in this thread that is important by its absence is that of getting dimensions accurate to sub mm lengths. Modern computer software is great for answering what if questions. What happens if the port is slightly too long or short? I don’t know the volume the drive unit takes in the cabinet so what happens if the volume alters slightly?

 

I’ve just done a simulation of a 2 x 18” cabinet (to stay on topic) using Eminence Kilomax drive units. I started with the predicted cabinet volume of 1500ltrs and adjusted the tuning to get a flatish response. I then created a new model with the same parameters which I could vary. Losing 200ltrs from the volume altered the response less than 1dB as did varying the port length by 1cm either side of the original (smaller shorter ports are more critical to length change). Dropping the volume down to 1000ltrs and slightly raising the tuning frequency gives a slightly flatter response and only raises the -3dB point from 20Hz – 23Hz.

 

As can be seen even not so small variations in the above cabinet aren’t that critical so if one panel has been cut 6mm too small the chances are that trimming the others down won’t be disastrous. If someone else is doing the cutting you can also emphasise that it is more important to ensure that panels with the same dimension are the same and if one is slightly out they all need to be out rather than making corrections on individual cuts.

 

Obviously it is best to be accurate to the calculated design (especially if there is only a 5mm clearance between the back of the drive unit and cabinet), but the advantage of rolling your own is that you are aware of the performance compromise needed to fit the cabinet in the back of your van.

 

A final word of warning. If the original design was a 50ltr cabinet you are on your own if you try to reduce the size by 100ltrs :)

[alex_kyuss]

Hi guys thanks for the reply guys.

Its been really helpful. I have been put off a bit and I think I may just go out and buy some.

Cheers all

[oxogoxo]

Hi guys thanks for the reply guys.

Its been really helpful. I have been put off a bit and I think I may just go out and buy some.

Cheers all

 

alex.check out thomanns ,free delivery and 3 year guarantee with low prices u might find your stuff there.best of luck it looks like too much hard work trying to build them I agree.

[itinerant baker]

It may not be easy or all that cheap to do a good job, but it'll be well worth it if you do. The plans on speaker plans are very good, and as has been said the knowledge on the forum is amazing. If you use the plans and do a good job you'll have excellent speakers at a lot less than you would pay for them if manufactured by a company - admittedly probably more than you'd pay for some red disco speakers, but they'll p*** on them from a great height. Spend a month or 2 going right through the site and generally researching the idea - there are even a few people who post on the forum who will build certain cabinet designs for you (if you cross their palm with silver of course).