Yesterday I promised we'd go over one of the significant advantages of using separate speaker cables for the top and bottom end of the loudspeaker. The practice is known as bi-wiring.
The general notion is that by separating the tweeter/midrange signals from the bass signals in separate cables, benefits of isolation are achieved. It's been suggested in the comments section of Paul's Posts that one benefit is isolating the back EMF from the woofer and lowering magnetic fields generated by the heavier current demands of the bass frequencies. While not convinced about the magnetic isolation benefits, clearly the back EMF arguments have merit.
EMF stands for Electro Motive Force. Sounds tricky but it's not. A woofer can act both as a microphone and as a driver. Put energy into that driver and it moves forward or backwards depending on the polarity of the energy you put in. But take your hand and push the woofer in and the same mechanism that moved the woofer now does the opposite: it becomes a generator and produces voltage. So every time the amp moves the speaker, the speaker 'pushes' back creating a voltage. That's what's being discussed here. Not having that 'extra' voltage from the woofer on the same wire as the tweeter and midrange could definitely have some benefits. And bi-wiring works, so, ok, I am a believer.
But to the subject of today's post, mixing and matching: using different cable constructions for each of the two speaker cable types. We've all heard differences in speaker cables. If you haven't, then you need to experiment a bit. Trust me, they exist. One cable might have great slam, impact and bass response while another sounds thin and anemic in that area, but terrific on the top end. I am sure you can see where this is going. By selecting different cable constructions maximizing the benefits of top end or bass performance, separate cables can sound far better than a single cable trying to be good at everything.
This idea has been around for some time now. Generally, heavy gauge cables sound full and rich in the bass, but depending on how they are constructed, not always the best performers on the top end. This type of cable would most likely work great for the bottom end cable.
So, now that you know how to maximize a bi-wire setup the question probably comes to mind 'how do cable manufacturers wind up making a single cable with both characteristics'?
I'll give you some insight into this tomorrow.
