DIY Speakers and Crossovers

Adarsh · « **on:** 8 Dec 2009, 10:31 am »

Hi AC folk!

I'm a new considering building my own speakers. I'm doing quite a bit of reading on the area and have a question about crossovers.

To make things easy I was considering getting a kit which includes drivers and matching crossovers.

My question is can I use these drivers and crossovers in any enclosure or does crossover design/specification depend on the cabinet?

Thanks,

-A

Anji12305 · « **Reply #1 on:** 8 Dec 2009, 01:18 pm »

If the driver is sealed in it's own capsule, you may use most any box.

Most Midrange and Low frequency drivers have an open basket that allows air movement to the rear.

The damping of this "back wave" is part of the art in loudspeaker design.

While you may have some lucky accidents by mixing and matching, staying with an established (and tested) design will provide simpler positive results. There are some VERY interesting designs on the Linkwitz site, and my favorite, Zaph Audio.

http://www.zaphaudio.com/

Wind Chaser · « **Reply #2 on:** 8 Dec 2009, 02:58 pm »

If you're looking for a kit, GR Research... http://www.gr-research.com/ offers a variety of kits that are outstanding by any standard.

http://www.gedlee.com/ ...is also worth checking out.

poseidonsvoice · « **Reply #3 on:** 8 Dec 2009, 03:15 pm »

Quote from: Anji12305 on 8 Dec 2009, 01:18 pm

If the driver is sealed in it's own capsule, you may use most any box.

Most Midrange and Low frequency drivers have an open basket that allows air movement to the rear.

The damping of this "back wave" is part of the art in loudspeaker design.

While you may have some lucky accidents by mixing and matching, staying with an established (and tested) design will provide simpler positive results. There are some VERY interesting designs on the Linkwitz site, and my favorite, Zaph Audio.

http://www.zaphaudio.com/

Quote from: Wind Chaser on 8 Dec 2009, 02:58 pm

If you're looking for a kit, GR Research... http://www.gr-research.com/ offers a variety of kits that are outstanding by any standard.

http://www.gedlee.com/ ...is also worth checking out.

+10 on both recommendations! Seriously Anji is giving very serious and excellent advice. Stick with EXPERIENCED designers. Look for measurements, ask for measurements. You'll see that Earl Geddes and a few others are in rare company in that regard. Your budget can determine a lot but you don't need to empty your bank account to obtain a good design.

Just a cursory glance at the measurements of some loudspeakers by Soundstage! will show you how there are very, very few designers that are in the 'ball park' and most who definitely are not. High price does not necessarily equal high performance.

Anand.

nodiak · « **Reply #4 on:** 8 Dec 2009, 03:21 pm »

Crossovers are designed for a certain baffle width and height, and driver location on the baffle. Imo takes years to develop the ear and skills (no i haven't). A kit will be quicker to get going, and a standard to compare any diy speakers you may want to build.
If you want to go into more discussion post your amp, source, room size, type of music. But be ready for an uh abundance of advice/opinion. If you own(ed) or have heard something you like say so, it would help focus a solution for you.
Don

richidoo · « **Reply #5 on:** 8 Dec 2009, 03:23 pm »

Selah Audio also has well engineered kits at good prices.

A great resource is the Loudspeaker Cookbook by Vance Dickason. It will tell you just about everything you need to know in a well written book. Another of his books, loudspeaker recipes builds 4 speakers step by step, focusing on crossovers.

Play around with a free simulator software like WinISD which will allow you to see how changes in box size and port geometry will affect FR and phase. Then just start building and listening. There is no substitute if you want to learn the "hows and whys".

nullspace · « **Reply #6 on:** 8 Dec 2009, 03:46 pm »

Quote from: Adarsh on 8 Dec 2009, 10:31 am

My question is can I use these drivers and crossovers in any enclosure or does crossover design/specification depend on the cabinet?

A well-designed kit's crossover will take into account the cabinet, dimesnsions and construction, and to use any other enclosure will change the original design -- to what degree, who knows.

Following a well-documented design is a great way to get started building your own speakers. Zaphaudio has been mentioned, and I'll second his designs.

If you find that you like building speakers, I'll second the recommendation of Vance Dickason's book and add that D'Appolito's 'Testing Loudspeakers' is mandatory reading. There's plenty of inexpensive/free measurement and simulation software around, a couple of jigs, some cabling, a measurement microphone, and you'll be set. If you build a kit, I would think it would be a good learning experience if you were able to 're-create' the design using your own measurements and simulations.

If you're looking for a learning experience and not 'the greatest speaker ever' in a kit, the dedicated kit manufacturers are probably more than you need -- find a design from ZaphAudio or elsewhere to follow and take the savings to set yourself up to build your own speakers.

Regards,
John

S Clark · « **Reply #7 on:** 8 Dec 2009, 04:02 pm »

All of the above are excellent options. It is difficult to make a diy effort work without computer measuring equipment, so stick to those projects that have been tested and are known to work. I'd also recommend projects designed by Dennis Murphy found at http://murphyblaster.com/content.php?f=main.html

Adarsh · « **Reply #8 on:** 8 Dec 2009, 11:17 pm »

As always, thank you guys for such a speedy response.

-A

hdspeakerman · « **Reply #9 on:** 8 Dec 2009, 11:33 pm »

Don't forget Parts Express and Madisound if you want diy speakers or kits. Howard

ps: It can become addictive!

S Clark · « **Reply #10 on:** 8 Dec 2009, 11:57 pm »

Quote from: hdspeakerman on 8 Dec 2009, 11:33 pm

Don't forget Parts Express and Madisound if you want diy speakers or kits. Howard
ps: It can become addictive!

The Parts Express and Madisound kits offer good value, but you'd get better sound from stuff designed by Danny Richie or Dennis Murphy. There are lots of guys that are pretty good at crossovers, but these guys go beyond "pretty good".

Wind Chaser · « **Reply #11 on:** 9 Dec 2009, 12:24 am »

Quote from: S Clark on 8 Dec 2009, 11:57 pm

but these guys go beyond "pretty good".

I can't speak for Dennis, but when it comes to crossovers, Danny at GR Research is the man! He can make almost any speaker sound significantly better.

richidoo · « **Reply #12 on:** 9 Dec 2009, 01:01 am »

Quote from: hdspeakerman on 8 Dec 2009, 11:33 pm

ps: It can become addictive!

Got that right Howard!

Adarsh · « **Reply #13 on:** 9 Dec 2009, 01:12 am »

Those ScanSpeak drivers seem a little bit pricey, does anyone know of floorstanding designs using Fostex drivers that are similar to the SP95s?

Kanimambo,
-A

S Clark · « **Reply #14 on:** 9 Dec 2009, 02:03 am »

Quote from: Adarsh on 9 Dec 2009, 01:12 am

Those ScanSpeak drivers seem a little bit pricey, does anyone know of floorstanding designs using Fostex drivers that are similar to the SP95s?

Kanimambo,
-A

It is often the case that a more expensive driver requires less components in the crossover than one with a more ragged response curve. You may save a few bucks drivers only to spend more in the crossover and get less audio fidelity for your investment.

Perhaps we are much overdue in asking specifically what are your goals? Could you describe the room in which these will go, your amplifier, and generally what you listen to and how loud? Also, budget?

Adarsh · « **Reply #15 on:** 9 Dec 2009, 02:09 am »

Ah I see, well it looks like this will be project for after I leave college

The room itself is not very large maybe 9 square meters. I haven't got any amplifiers yet, but I hope to shop around some vintage joints and get something not too expensive like a Pioneer. Would a Pioneer be sufficient for this job?

The source will be my MacBook Pro and iTunes.

So, as you can see I'm not looking to fork out more than a 3 figure budget on this project. Also I'm not expecting to get SACD CD or anything like that. The best from a Mac setup will suffice.

Thanks for your help

S Clark · « **Reply #16 on:** 9 Dec 2009, 03:58 am »

OK, I've got a much better picture of what to recommend.
Option A- easy and cheap
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=300-652&utm_source=Parts-Express&utm_medium=Flash+Panel&utm_content=B652+11-24-2009&utm_campaign=Home+Page+Flash+Panel&utm_source=Parts-Express&utm_medium=Flash+Panel&utm_content=B652B+12-04-2009&utm_campaign=Home+Page+Flash+Panel
After college, give them to an underclassman or use them in the bedroom and get a set of something better.

Option B- Two of these cabinets
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=302-720

and either: http://www.gr-research.com/index.asp?PageAction=VIEWPROD&ProdID=146 OR
http://murphyblaster.com/content.php?f=MB20.html

You would have to cut out the holes for the drivers, and solder the crossovers, but overall, most of the hard part is avoided by buying the cabinets. You end up with a very nice set of compact speakers that will travel with you after college for less than $500. Both use the M130 midwoofer that goes surprisingly deep in .5 cubic ft (down to 50Hz). You can't go wrong here.

Look for a used integrated amp, or find a cheap T amp (Sonic Impact<$70)

Adarsh · « **Reply #17 on:** 9 Dec 2009, 04:48 am »

S_Clark, thanks for the suggestions.

I'm curious to know what your reasoning was behind recommending bookshelf speakers.
Do these speakers churn out the same quality as would floorstanding speakers such as the SP95?

S Clark · « **Reply #18 on:** 9 Dec 2009, 06:39 am »

I'm figuring your in college, but soon to leave. Most college grads start off in an apartment with space as a premium, hence the smaller speakers. However, add a pair of subs to the last two options and you still fill a large room with quality sound.
If you build the larger variations from either Murphy or Richie, it will be harder to buy prebuilt, prefinished cabinets. Most college students don't have a garage full of power tools.

I just checked out the SP95 that you mentioned... a large cabinet, 3way crossovers, pricey drivers... unless you have the tools, not a practical project... and not cheap.

I just noticed that you were considering the Audioengin A5. That would also be an excellent choice if you need an amp as well.

MerlinWerks · « **Reply #19 on:** 9 Dec 2009, 03:19 pm »

Although not in stock at the moment, a lot of people seem to be happy with THESE, more build info can be found on the PE board. Seems like a pretty sweet deal, especially for the first time...