Maker Pro
Maker Pro

Help building a crossover

tuato

Sep 18, 2010
3
Joined
Sep 18, 2010
Messages
3
Hello, i need some help about a crossover for my hi-fi speakers. I've got a Beyma 12ga50 and a Tweeter inside a Marshall Cabinet and i wanted them to play guitar with a POD XT fx modeler through an HH head amplifier. Well, I've been reading out there about the need of a crossover to get the full range of frequencies for my speakers, and i'd like to build one by myself.

The problem is that i don't know what kind of components i must use, i mean , the Farads, the kind of coils etc....

If anyone here could help me with these things it would be great, thanks in advance.
 

hevans1944

Hop - AC8NS
Jun 21, 2012
4,878
Joined
Jun 21, 2012
Messages
4,878
The Beyma 12ga50 is a "full musical range" loudspeaker and doesn't require a crossover network. But you didn't specify what Tweeter you are using with this speaker. To protect the Tweeter from low frequencies you can install a small capacitor in series with the Tweeter leads. Try a one microfarad plastic (non-polarized) capacitor rated at 16 V or more. If the sound isn't "bright" enough on the high end of the frequency spectrum, you can increase the capacitance. If it is too "bright" you can use a smaller valued capacitor.

There is plenty of DIY information on the Internet to allow you to build a crossover network, but most of it requires you to know a lot of electrical information about the speakers. You might want to start with this page for the big speaker and find a similar one for the Tweeter before embarking on your quest.
 

tuato

Sep 18, 2010
3
Joined
Sep 18, 2010
Messages
3
specs.jpg Thanks for your reply, it looks very easy to get the tweeter works. I send you the specs of the Tweeter, it's a Beyma T-2030, i hope it's useful.
 

hevans1944

Hop - AC8NS
Jun 21, 2012
4,878
Joined
Jun 21, 2012
Messages
4,878
Great! Now go to this page, plug in the speaker impedance (8 ohms, both speakers), and select whichever type of crossover network you want. I would start with the simple Butterworth filter at 2000 Hz (as recommend by the Tweeter datasheet you posted). This uses one capacitor and one inductor.
 

Sunnysky

Jul 15, 2016
541
Joined
Jul 15, 2016
Messages
541
There are a few more critical details.
The cap needs to be a high quality non-polarized cap. A non-polar electrolytic may work, but polypropylene is much better (PP) http://www.digikey.ca/product-detail/en/nichicon/EXH2E705HRPT/493-13830-ND/4694507

The inductor should not saturate with a couple Amps and must have a low DCR value. In this case pro's use only large diameter air core magnet wire coils.

Also use the lowest impedance, not 8 Ω, which is nominal.
 
Top