Bi-wiring with different cables for HF and LF?

I'm thinking the DNA1 is a very good amp, and should give you what you're looking for. What is the rest of your system, source, preamp, interconnects? Also, position of speaker in room, distance from back wall and side wall?

Mtrot, when I initially brought up the coherence issue, I should have offered an explanation as well, sorry I did not. Since this has come up again, and you are asking questions pertaining to frequency, then hopefully this will help you to understand.

Stereophile definition - “coherent 1) Pertaining to a multi-way loudspeaker's sound: seamless from top to bottom; showing no audible evidence of a crossover or of different driver colorations in different frequency ranges. 2) Pertaining to the soundstage: Phantom imaging that reproduces within the stereo stage the original lateral positions of the performers.”

I’ll use 60Hz as the fundamental frequency for the explanation which is definitely in the range for a kick drum or bass (guitar or upright). Along with the 60Hz, something called overtones or harmonics are also created. 2nd order is 120Hz, 3rd order is 180Hz, 4th order is 240Hz, 5th order is 300Hz, and so on. How high do they go? I don’t know, but in my research, I found several saying up to 5kHz, and even higher for that bass note. These overtones or harmonics give the instrument its timbre or characteristic sound. Look at the graph in the link below (at the paragraph titled “Spectra and harmonics”). It is for a 400Hz note from a flute, but gives you a visual for what I’m saying. Notice that the 3rd order harmonic at 1200Hz is just slightly lower in amplitude than the 400Hz. Not all graphs will be the same, since the amplitude of individual frequencies and how fast they taper off will be determined by a particular instrument.

http://www.phys.unsw.edu.au/jw/sound.spectrum.html

Now we play this 60Hz note on your system. As the frequency of overtones increase, they reach a point, determined by the crossover in the speaker, in which they will NOT be produced by the driver producing the fundamental frequency, but the next driver, or drivers depending on how high they actually go.

Every cable or wire will have electrical properties, capacitance, inductance, and resistance. These properties will vary with all the different manufacturing techniques and materials. It’s this variation that contributes to a slight altering of signal transfer between components, or as in your case, amp to speaker, resulting in a difference of the sound. It’s true you might stumble upon two that would be real close, but for the properties to be identical, the cables must be identical.

So when you use identical cables, the signal feeding the driver or drivers producing the overtones is identical to the signal feeding the driver for the fundamental frequency, resulting in accurate timbre. Using different cables will alter the overtones that are NOT feed to the driver producing the fundamental frequency, therefore degrading the timbre accuracy of the sound. As I said before, I think it may be possible to stumble into two cables that would be real close and work OK together, but that would seem to be a huge undertaking with a multi driver 4-way speaker. A 2-way might not be as difficult.

Agree that it’s a bad idea. In another thread on this forum, a well respected amplifier designer commented that NOT using identical cable and length would create problems with coherence. Sounds to me like using different cables is just working against what you are trying to achieve.

Not a problem, why not order another pair of Morrow SP-2 on their trial, then use your broken in pair on the LF. I wouldn't be overly concerned about gauge. A couple of years ago, I used Audience Au24, a very small cable, and the bass was extremely good.

Mtrot, your original post said you wanted to improve bass definition. Here is an article from Audioquest on Bi-wiring that talks about bass definition. The first page and a half is definitely worth reading.

http://www2.audioquest.com/wp-content/uploads/2012/02/UndrstndgBiWr.pdf

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