Tube Monoblock location? - Rack or near speakers?

This is one advantage of balanced cables. The shorter you can keep the speaker cables, the better (more resolution, more impact). Preamps that have a low output impedance can drive longer cables, so some single ended preamps will allow up to 20 feet (although that is rare). For the most part, running longer cables than that is best done with balanced lines. My cables at home are 35 feet.

Vibration in the tubes is generally **not** a problem!

Hifitime, if you think about it, a tube amp sitting beside a speaker is not going to get any more vibration than one far away. But really, if you try the difference between long speaker cables and short interconnects as opposed to short speaker cables with the amps near the speakers and long interconnects, the across-the-band improvement is instantly audible. IOW, apparently the vibration issue does not seem to play a role.

For 4 ohms, 1 meter, for 8 ohms, 2 meters and 4 meters if 16 ohms. Hifitime, I have never heard what you are saying about balanced lines and it is simply untrue. You might tell whoever told you that that they are full of beans. I have yet to see RF problems in a balanced cable- the assertion is absurd!

Balanced lines were developed originally by the phone company decades ago and made trans-continental phone calls possible. A few years later they were in common use in the recording industry- most of your records and CDs were recorded with them, in some cases the cables were over 150 feet long.

In the home they solve the issue of speaker cable length quite elegantly. **If** the preamp supports the balanced line standard, then the length and the cost of the cable is not important in the overall sound. I have seen my 30 foot $85 pair of Mogami Neglex be indistinguishable from a $24,000 set of balanced cables 24 feet long. (The system was mbl101e speakers, with mbl power amps driven balanced by our MP-1)

I've done numerous PA setups over the years. One might interest you. It was in a concert hall- we needed a PA for the singers. The speakers were mounted in the ceiling so we set up amps and ran 40 feet of speaker cable to the speakers. You could not make out the words they were singing! Then we moved the amps to the speakers and ran the same cable, shortened to 1 meter long. We set up a transformer system that allowed us to run a balanced line between the mixer and the amps- the instant increase in clarity was startling!

I've done the same thing in my home, and BTW have a set of SRA stands for our amps as well. They do help (they are some of the best), but by far the bigger difference is seen in keeping the speaker cables short as possible. Since we can run a balanced line of any length with our preamps this is a very easy test to perform.

Hifitime, true, if the noise is in the signal. False, if the noise is common-mode (for example, impinged on the cable itself). Of course, you need a balanced input at the amp to take advantage of that.

5 meters is a long way to run single-ended cables.

FWIW your dealer must not know what balanced lines can do. His statement is preposturous.

But since the CAT has a single-ended input, and because the ARC does not support the balanced standard (which includes the ability to drive 600 ohms- you'll find it looses bass and output when trying to drive such a load) you are probably better off running the long single-ended cables. I know that the preamp has a 600 ohm output impedance but that is not the same as saying it can **drive** 600 ohms, and for balanced operation, that is important.

If the ARC did support the standard, you could run balanced lines to a set of transformers that could convert balanced to single ended right at the input of the amps. That way the length of the cable would not be a source of degradation. Jensen makes a nice set of transformers for that purpose that are 600 ohm to 600 ohm- now you see why I mentioned that part of the balanced line standard.