Digital crossover signal routing

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During swapping amplifiers recently I decided to try a different than the usual routing of signals on my sound card. I found something worth noting. Here is the background:

Different converters have different specs when it comes to channel separation, especially when you consider the different analog stages that follow the DA converter chip. Normally it is natural to assign bass left and right to one pair of outputs, mids left and right to another pair and so on. So with that "normal" connection left and right channel separation spec of the converter is preserved. Left bass information bleeds into right bass, left mids bleed into right mids, left highs bleed into right highs.

I decided to organize my crossover outputs in a different fashion to see if there is an audible difference. So, I connected outputs 1-4 on my 8 channel converter to the left speaker and channels 5-8 to the right speaker. Now the bleed within each stereo converter is between lows and mids1, and mids2 and highs. But, the crossover filters overlap anyway, so the bleed is much harder to detect. With this configuration our left and right speakers don't share any part of the stereo converters- other than common power supply.
I have to report that in my system the separation of speakers with this configuration is definitely improved. The stereo image is better defined.
The connection goes as follows:
allocator out - sound card out
1 - 1
2 - 5
3 - 2
4 - 6
5 - 3
6 - 7
7 - 4
8 - 8

You can also see the diagram I drew to illustrate the two different connections. www.thuneau.com/images/allocator-connections.pdf .
Notice the amplifier channels are also better isolated in this connection.

Improved separation might not be the case with every sound card or converter on the market, but it makes a difference with the Alesis AI-3 and the 8-channel Lab Gruppen C 10:8X amplifier I just got.

BTW, the Lab Gruppen switcher is very nice with the only drawback being the fan which is audible even at the low setting- but only with very quiet music. It's about as loud as a normal PC. Once the music is played at normal level- 75-80dB SPL I can't really hear the amp fan.
The low frequency control and clarity of the amp is outstanding. It should be worth building a little iso-enclosure to suppress the noise.
 
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