Need help on building crossovers.

[Fishtails]

Hi people

I was wondering if anyone can point me to a thread on making your own two way crossovers or if anyone has a good link.

Thanks!!

[bauzace50]

Hi,

go to www.madisoundspeakerstore.com They are one of the oldest suppliers to speaker builders, and have several books on speaker design. Alternatively, they could design a crossover for you, depending on the specifications of your drivers.

Be aware that optimal crossover design accounts for specific drivers in specific cabinet application, and specific testing and corroboration are preferred. A general-purpose recipe can hit or miss.

Note that passive crossover capacitors for loudspeakers are of the special Non-Polar variety, usuallly supplied by Speaker Builder vendors. The regular polar capacitors are not used in speaker crossovers.

Regards,
bauzace50

[analogaudio]

http://www.trueaudio.com/ild_abt1.htm

[cafe latte]

Hi people

I was wondering if anyone can point me to a thread on making your own two way crossovers or if anyone has a good link.

Thanks!!

Jaycar sells all the stuff to make your own including the boards so you can just slot the components in, both 2 and 3 way. I tried to find out about modding crossovers on another forum, but all the responses I got were basically its a black art and you wont be able too . Anyway after some help here on VE and lots of research I found what I needed to know. Get a book on speaker building which is what I am going to do to try and understand a bit more, but I dont think that if you have the curves of all the drivers and you know the sensitivity of the drivers it will be hit and miss. As long as you cross over away from the drivers resinance freq and you match your drivers correctly with resistors I cant see why you should not get a good result as long as you have the correct port length for box size (dont forget lining the box makes the port see a bigger box).
Regards
CL

[josephazannieri]

Yo Fishtails:

This may not be what you were looking for, but I suggest some BOOKS that have good basic information on coossover design. Anybody remember books? I even have some, but I am OLD.

1. Hi-Fi Loudspeakers and Enclosures, by Abraham B. Cohen, Hayden Book Co. 1968. This is the book that gave me my basic understanding of how to build crossovers and how to set them up. This is pre-Thiele Small, and pre-computer, but it gives a good chart for figuring out component values for networks.

2. Loudspeaker Design Cookbook by Vance Dickason, Audio Amateur Press, 2000. There is a new seventh edition. Crossover formulas are great, and permit you to figure everything. This is the current basic reference on all aspects of speaker design.

3. Advanced Speaker Systems, by Ray Alden. Master Publishing, 1995. Ray Alden is a high school math teacher who does a unit where his kids build speakers as a math project. The book is great because Alden tells you which buttons to press on your TI 13 scientific calculator to get the results you need. Alden a has a new book called Speaker Design 101, which is similar in philosophy.

The Loudspeaker Design Cookbook is readly available everywhere, such as Parts Express and other electronic suppliers. It gives good criteria and discussion of the advantages and disadvantages of each design configuration.

I realize that books are not websites, but these books are recognized as good authorities, and everything in them is true. Websites may or may not be as reliable.

And good luck from the old reader, mired in the paper past,

Joe Z.

[charlieblue]

My favorite site on diy projects would be Elliott Sound Products. Straight up, clean and informative. Please see the page on crossovers :
http://sound.westhost.com/projects-3.htm

Have been for ages wanting to do his project No09 crossed at 150Hz, which is ideal for my wideband driver. Unfortunatelly, my hands are now so shaky , the other day it took me 15 minutes only to open a power plug, reverse polarity and close it back again ... and I did not solder the leads either...

Anyhow, even if you never try any of the projects on Elliott's website, you will learn a lot just by reading through... I know I did

Best,

Charlie

PS. Hey Fishtails, did I mention, Elliott is in the land down under, just like you are ? Thumb's up for supporting the local economy!

[andyr]

Unfortunately, my hands are now so shaky , the other day it took me 15 minutes only to open a power plug, reverse polarity and close it back again ... and I did not solder the leads either...

Best,

Charlie

I'm wondering why you did this (reverse polarity), Charlie? Because, surely, it means that the mains fuse in your device that's connected to this plug is now on the "neutral" wire, rather than the "active" wire - which is bad.

BTW, I have been using Rod's P09 XO boards for the last 12 years in my 3-way active Maggies (although I have modified the slopes from standard values).

Regards,

Andy

[charlieblue]

Hi Andy,

It must be 10 years now since I first read this article on how to wire the mains :
http://www.soundstage.com/weaver01.htm
Recently I came up to an update on this, saved it somewhere then lost the link.
Typical for my receding memory, and hairline

Anyhow, I thought its was just about time I tried out the tweak, only with a twist: first try by listening tests, then measure the voltages and confirm the actual tweak.

Well, I tried the first polarity change, taking notes all along, and then prety much gave up: cannot seem to find any time to listen to music, much less go on experimenting .

But, I haven't lost hope yet, my summer vacation is coming up fast! That's 2 weeks of happy tweaking for me

Best,

Charlie

[andyr]

Hi Andy,

It must be 10 years now since I first read this article on how to wire the mains :
http://www.soundstage.com/weaver01.htm
Recently I came up to an update on this, saved it somewhere then lost the link.
Typical for my receding memory, and hairline

Anyhow, I thought its was just about time I tried out the tweak, only with a twist: first try by listening tests, then measure the voltages and confirm the actual tweak.

Well, I tried the first polarity change, taking notes all along, and then prety much gave up: cannot seem to find any time to listen to music, much less go on experimenting .

But, I haven't lost hope yet, my summer vacation is coming up fast! That's 2 weeks of happy tweaking for me

Best,

Charlie

Yes, Charlie - I read the same article about 10 years ago, too! Although the one I have (I printed it out) is slightly different - much longer! Here's my link FYI (in case it's the one you forgot):
www.boundforsound.com/tweak.htm

I do this test as a matter of course with all the kit I build - in fact, I always use a DPDT mains switch which has the active & neutral reversed on one side, for easy switching/comparing. However, IMO the way you should really go about it is (forget the 'listening'!):
* make up a short (1' long) extension cord which swaps the mains polarity
* plug the device into the wall normally and measure the voltage, as the article describes
* then plug it into the 'reversed' extension cord and re-measure
* if the latter config is the lower voltage, you need to reverse the pair of wires to the mains transformer, at the mains switch. That way, the fuse remains on the 'active' line.

Regards,

Andy

[charlieblue]

Yup...that's the one, great article !
Thank you Andy, both for the link and the tips !

[Whitneyville]

Come on over and visit (better yet join) the Parts-Express.com Tech-Talk Forum, and download Jeff Bagby's Passive Crossover Designer free (yes free!) software, and we'll have you talking elliptical second order filters as opposed to third order Likwitz-Riley cross-overs, in no time at all! PCD let's you use your computer instead of pages and pages of math, that isn't even of the same order of accuracy your 'puter-thingey can do in a split-second. Before you buy one part, you can "test" thousands with the same software several very prestigious speaker manufacturers use to design and refine (in one case) $40,000 (each) speaker systems on. Years ago, cross-over design was "black-magic" because the math was so intense and we didn't know all the things about drivers we needed to measure. Now we do, and it's very easy, and down-right cheap to do, then you punch in the numbers into the program and play with it. Do you want maximum accuracy? Click-bang. Maximum volume (SPL) in a given size enclosure? Click-bang. Flattest frequency response? Click-bang. You want ALL of these and see how they interact? Click-click-click. This has some possibilities....eh?

[andyr]

Come on over and visit (better yet join) the Parts-Express.com Tech-Talk Forum, and ... we'll have you talking elliptical second order filters as opposed to third order Likwitz-Riley cross-overs

AIUI, L-R filters are always even order ... ie. 12/24/48dB etc.

Regards.

Andy