Good question. Which offers a greater gain? Shorter high voltage/current speaker wire or shorter small signal more sensitive to noise cable?

I've heard recommendations that the long IC's are better than long speaker cables, provided that the source impedance into the IC's is low enough, and a balanced line certainly helps.

Longer speaker cables may add more resistance (said to affect damping factor, i.e. control of the speaker cone at low frequencies), and some capacitance and inductance. But larger cable diameters has lower resistance per foot. You would need to experiment whether this approach is worth the expense, time, and sonic improvement.

The conventional wisdom is that short speaker cables and long interconnects is the better of the two options.

If those long ICs can be balanced it'll be win-win. Long runs of unbalanced IC are at high risk of picking up RFI. The degree will be environment dependent.

The long runs of mic cables that engineers routinely use are all balanced. Your environment is not likely to be as ugly as a stage littered with mic cables, amps, monitors, etc., but it's best to go with unbalanced if you have the choice.

Dave

Your choice should first of all be determined by the output impedance of your pre amp and the input impedance of your amplifier(s). You are hoping for an input impedance as high as possible within practical limits. My older McIntosh tube amplifiers have a nominal 250k Ohm input impedance which allows virtually any modern pre amp to operate well with long interconnects. Most more modern power amps will have a stated input impedance below 100k Ohms with some much lower than that.

You should realize that impedance is not a fixed number, therefore the word "nominal" or "average" applies, but that it swings up and down in relation to frequency so the nominal number might be based on a very hopeful situation used to make the number look best to a prospective buyer. It is always better to find an actual measurement if your amplifier has been tested by a high quality review magazine. Otherwise you might want to call the manufacturer for specific information regarding their preference for cable runs and any actual measurement information. Look at the input impedance spec for your amplifier as a starting point to determine how manageable long interconnects might be.

Most importantly look at the output impedance spec of your pre amplifier since this is the driving force you have to work with. If your pre amp states a nominal output impedance of more than 600 Ohms, then you should not consider anything more than a 2 meter pair of interconnects running to the power amp. And that's pretty much the bottom line on what you need to consider. Below 600 Ohms output impedance you can easily consider a long cable run to the power amp. Above 600 Ohms, you will need a very high input impedance on your power amplifier to make long interconnects work.

As always, the ideal suggestion is to compare both options but in the real world that is nearly always impossible so the above guidelines should be observed. You can however make up your own inexpensive interconnects and speaker cables with good quality components and listen at minimal cost. Place "DIY interconnects and speaker cables" in a search engine and consider your skills at building cables for experimentation. Here's a set that is easily constructed if you have good soldering skills and the materials are cheap and readily available; http://www.6moons.com/audioreviews/whitelightning/moonshine.html

Most interconnects are shielded to protect against RFI/EMI pickup and some are not. Your environment and location will determine whether you will require shielding on your interconnects. I live in a metropolitan area and can get by without shielding on my shorter cables but not my longer cables. A friend uses long interconnects between pre and power amplifiers without any shielding. We both use a variation on the 30 AWG interconnects found here; http://forum.stereophile.com/forum/showf...part=1&vc=1

One difference in our installations is the presence of dimmers on all the lighting fixtures in my house vs none for my friend's location. Try a few designs since most are relatively inexpensive and listen for any problems. Cables using twisted conductor construction such as the White Ligtning cables above have some advantage over parallel conductors runs when it comes to cancelling noise. Whether you decide to keep your DIY cables will be your choice but they will provide an opportunity to make comparisons between long/short interconnects before you spend big money for after market cables.

Of course, the same rules apply when using DIY cables as with any other cable, check the manufacturer's specs for your impedance match before you do anything else. Great cables cannot make up for an improper electrical match.

In studio quality gear the 600 Ohm mark has been a long standing reference. In consumer audio it has been available for several decades in many products. My tube pre amp has a nominal 600 Ohm output and it's been around since the late 1980's. Look at a few of the models in Stereophile's review archives to see which models fall higher and lower than that number. Since input impedance is always meant to be relatively high when compared to output impedance achieving a low output impedance in a pre amp can mean the designer has either done some very careful manipulation of the design or additional circuitry has been added to lower the final output impedance to an acceptable level.

In bare bones, hot rod units where absolutely nothing that is not required will find its way into the pre amp the output impedance is probably higher than 600 Ohms unless the price is much higher than average. You'll find many passive pre amps with quite high output impedance specs since there is no active circuitry employed and the actual output impedance will vary with the setting of the volume control. This is the benefit of active pre amps but they inevitably introduce noise, distortion and colorations not found in a passive design. You'll also probably notice more solid state pre amps with low output impedance vs tube pre amps. As such I would not consider a pre amp with a higher than 600 Ohm impedance to be inferior, rather just a designer's choice. It still comes down to matching the output impedance of the pre amp with the input impedance of the power amp that matters. Keep one as low as possible and the other as high as possible and you'll most likely do fine with cable runs. And like all things in audio there are trade offs no matter which way you go.

To the best of my knowledge, 600 Ohms became the standard for analog telphone systems many years ago. To minimize reflections (echos) and maximize power transfer with transmission over long distances (miles), the system required that the input and output impedances of the sending and receiving equipment be closely matched as well as the characteristic impedance of the line itself. Some pro audio equiment also uses this standard as there is often several hundred feet of cable between equipment. For consumer audio equipment that is used in the home, the distances between equipment is much shorter essentially eliminating the need for this impedance matching.

For effective transmission of audio signals in the home environment, the basic guide is output impedances should be low and input impedances significantly higher. A quick review of some of JA's measurments of input and output impedance of both SS and tube equipment shows typical output impedances of at most a few hundred ohms while input impedances are typically a few tens of thousands of ohms. Consumer preamps with output impedances of 600 ohms are rare. Consumer amps with input impedances of 600 ohms are extremely rare.

Back to your original question, if your amp is separated from your preamp by a significant distance (say ~30 feet), you'll get better noise immunity using balanced connections. If all your equipment is in the same rack located between your speakers, it is unlikely you'll find any real real advantage of balanced over unbalanced connections.

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Would it help at all if I said I want (at minimum) a tube line stage and probably tube amps to drive a pair of Gallo 3.1s?

Nope. No help. The speakers don't really care about the length of the cables unless you've got some tweaky cables with unusually high capacitance. Avoid Litz type cables for any long run. Cables with high numbers of small conductors in individually insulated twisted runs are not a good choice either, think Kimber when imagining what this cable might look like.

Using simple zip cord at speaker level, however, signals can be sent over several hundred feet of cable without any significant loss or additions with just a bit of attention to numbers and placement of the cables.

The answer is still in the measurements for the pre amp and power amp. You should have at least a 1 into 10 ratio from pre to power amp. If you find a pre amp with an output impedance of 500 Ohms, you will need a power amp with an input impedance of at least 5,000 Ohms. That shouldn't be difficult to come up with. A higher input impedance is generally more desireable than a lower input impedance spec. The output impedance of the pre amp will determine whether you should attempt long cable runs. Avoid passive pre amp sections if you want long interconnects. And maintain a low capacitance and inductance per foot in both your cable choices.

Then you should listen to the two options to determine where you detect any improvement with one connection vs the other. If you can't listen, trust the numbers and go with what works out best on paper.

I might add that some incorporate an additional stage to obtain a very low impedance, (100 ohms etc). One has to then judge if the reduction in sound quality because of the additional stage is worth being able to run a longer IC between the preamplifier and amplifier. I find that it is not worth it.

Hope this helps.

Right, a buffered output or additional stages arranged in a cascade/cascode fashion will lower the output impedance. But any additional circuitry will come at some cost in additional noise and distortion. A very good designer should be able to minimize the damage and you then will decide what advantages are to be found with the additions. There is no free lunch in audio. If you get one thing, there will surely be another that is either taken away or, at the very least, somewhat diminished. Does a low output impedance gained through the use of additional circuitry outweigh the advantages of short speaker cables? Some listeners will say no while others will want the option.

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Their small size meant that I could put the D-100s very close to my speakers, however, so I used a long interconnect and my shortest speaker cables.

http://stereophile.com/solidpoweramps/805cia/index1.html

High impedance on long runs can also be a recipe for noise.

it is wiser to search out a preamp one likes, with low output impedance - and use amps with an 'average' (10kohms to 47kohms-lower is better)input impedance. Higher current drive usually equals better noise immunity.