noob question: computer soundcard's RCA to BX8a's TRS/ XLR

[Lotus 7]

Originally Posted by tt061880

Hello everyone, please let me ask an ubernoob question. I want to use the BX8a as computer speakers. My sound card has RCA output, I understand that RCA is unbalanced. If I am to get converter, which one yields better sound quality? RCA >> TRS or RCA >> XLR? TIA everyone.

If by "converter" you mean a cable adapter, it really makes no difference. XLRs are a somewhat more reliable connector, so since your M-Audio powered speakers have both, you might get the RCA to XLR adapters. With either choice, you still will be driving them with an unbalanced signal. The other issue is that your sound-card RCA outputs are probably set for a -10 dB line level and the speaker XLR or TRS inputs probably expect a +4 db level (much higher).

The BX8a has a variable gain control, and at the higher settings can "just" be fully driven by a -10dB output. Expect to have the level knob turned up almost all the way.

There are unbalanced to balanced converters that use transformers or active electronics, but are not appropriate for your application because they are relatively costly compared to the cost of your RCA-output soundcard, and as long as your cable runs are not extremely long (less than 10 meters), won't contribute to your sound being any better.

If I were doing what you want to do, I'd plug a female RCA to Male XLR adapter into each of the BX8as, and then run a good quality RCA/RCA cable out to each. Putting the adapters at the sound card means you will have to run (more expensive) XLR/XLR cables, and even though those cables are "balanced", your signal is still unbalanced and the "balanced" cables are totally unnecessary here. Unfortunately, running an unbalanced (single-ended) signal through a "balanced" cable does not make it into a balanced signal. In your situation, using plain RCA/RCA cables is no disadvantage.

Hope this makes sense to you.

[tt061880]

Originally Posted by Lotus 7

If by "converter" you mean a cable adapter, it really makes no difference. XLRs are a somewhat more reliable connector, so since your M-Audio powered speakers have both, you might get the RCA to XLR adapters. With either choice, you still will be driving them with an unbalanced signal. The other issue is that your sound-card RCA outputs are probably set for a -10 dB line level and the speaker XLR or TRS inputs probably expect a +4 db level (much higher).

The BX8a has a variable gain control, and at the higher settings can "just" be fully driven by a -10dB output. Expect to have the level knob turned up almost all the way.

There are unbalanced to balanced converters that use transformers or active electronics, but are not appropriate for you application because they are relatively costly compared to the cost of your RCA-output soundcard, and as long as your cable runs are not extremely long (less than 10 meters), won't contribute to your sound being any better.

If I were doing what you want to do, I'd plug a female RCA to Male XLR adapter into each of the BX8as, and then run a good quality RCA/RCA cable out to each. Putting the adapters at the sound card means you will have to run (more expensive) XLR/XLR cables, and even though those cables are "balanced", your signal is still unbalanced and the "balanced" cables are totally unnecessary here. Unfortunately, running an unbalanced (single-ended) signal through a "balanced" cable does not make it into a balanced signal. In your situation, using plain RCA/RCA cables is no disadvantage.

Hope this makes sense to you.

It totally makes sense, thank you very much! I'll just up the boost on the bx8a to compensate for the low output on my soundcard, once again thank you very much.