Speaker Crossover

How to Effectively use a PC for your DIY Speaker Projects – Speaker Crossover:
Have you been interested in making your own DIY speaker crossover? Speaker building has never been easier than it is now. The DIY speaker projects and products that are available on the market can be combined to create a state of the art playback system with extremely high performance.

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Digital crossovers are breaking new ground for transparency and fidelity and now the latest DAC processors are available to be used with a PC. Many of these DAC solutions are professional level, high quality multichannel digital to analog converters just begging to be added to a speaker system.
To learn more about this new way to use the latest DACs do a search on this site for our speaker crossovers articles. There are tons of articles covering this subject.

What you may need for a DIY Speaker Crossover Projects or Digital Software Crossover:

1. A reasonably fast computer; 2.5GHz quad core (minimum) with 4GB RAM (preferably DDR3 1600MHz or higher) and a 64 bit Operating System.
2. A firewire output on the computer (can get a card for the PCI slot in none on existing motherboard)
3. An SPDF digital output on the computer (usually built into the motherboard) can also use an expansion card in the PCI slot.tinyfoobar
4. A professional sound card –often called a firewire interface box (I like the Echo Audiofire8 or 12)
5. A multichannel preamplifier (at least 6 channels, including the subwoofer) a surround sound processor will work, as will a multi-channel home theater receiver.
6. An amp channel for each ‘way’ of your speaker system: (the tweeter of one speaker is one way for example) If you have 3 way stereo speakers you will need 6 amp channels. (can be included in a home theater receiver)
7. A speaker system with no passive crossover networks; this can be a set of speakers that you have made or have modified from
8. A software digital crossover such as available through the Allocator Lite.
9. A Blu Ray Player for watching Blu Ray discs.
10. A digital switch to bring in multiple digital streams into the PC from other sources.

The software you can use for this type of a system is a long list. I will show the software that I have used personally:

1. Foobar crossover component: This filter system uses IIR filters which are thought to be inferior to FIR filters. But for some reason I have found the Foobar crossover to sound better than some others for music playback. This could be that the inherent ringing of IIR filters can sound more musical. Kind of like listening to a tube amp.

a. Foobar Also has a convolution component that allows you to use the reversed peaks of your room response as a WAV file. You will need a measurement program like Room EQ Wizard to make the measurements and produce the WAV file.
b. When you play back your music, it plays it over this file like a finger print correcting the room (room correction) as it plays in real time.

2. Thuneau has an Allocator Lite and Allocator that provides filters and slopes for each driver. In addition it also has correction bands for each speaker driver to not only correct for speaker response but also for making corrections of the measured room response.
a. Again, you will first need to make some measurements using Room EQ Wizard to get your necessary filter locations. You won’t be using a WAV file though as in the Foobar convolution component.
b. By taking measurements from test sweeps you can effectively put in a correction filter, make a test sweep and record the change seeing exactly what your correction filter has done to the response.
c. You will need to load the filter and slopes into the individual crossover legs to use the correction function. (the manual spells out how to do this very easily)Digital-software-crossover
To some degree the above filters and slopes will depend on your equipment and gear (as to which will sound the best).
I think that this is the best part of the experiment. You can really see how much difference your tweaking is making to your music and movies playback.
Don’t believe me?
Try one of these systems out for yourself.
You can download the Foobar Player for free. The crossover component ad on is free too.
You will just need a few pieces of equipment to put it together. (A receiver, multi-channel soundcard with ASIO support) These are the most common items that you may not have.
Any speaker system could be modified by de-soldering the speaker wires from the crossover and adding more binding posts onto the back of the speaker cabinet. Then the extra amps could be hooked up to use the active crossover.
For measuring your system use the Room EQ wizard software from Home Theater Shack. It’s a free download too and works quite well for taking in-room measurements. If you put all the parts of this type of system together you will end up with one very versatile machine that will give you years of tweaking and satisfaction. I don’t think I would do it any other way. (And I have tried)