Long ICs versus long speaker cables

Dpe,

Fortunately most of the Cardas cables have very low capacitance, with the Golden Cross at 25.5 pf/ft, and the Golden Reference at 12 pf/ft in single-ended form (and lower in each case in balanced form, but it looks like the LA-150 only has unbalanced outputs).

25pf/ft x 20 feet (slightly more than 6 meters) = 500 pf.

The capacitive reactance (impedance) of 500 pf at 20kHz is

1/(2 x pi x f x C) = 1/(2 x 3.14 x 20,000 x (500exp-12))
= 15,924 ohms.

That is very comfortably higher than both of the preamp's selectable output impedances. It can be expected that the 400 ohm and 1200 ohm output impedances will vary significantly with frequency, but I suspect that they would only rise significantly above those numbers at deep bass frequencies, where cable capacitance is unimportant.

So I think you will be fine as far as cable capacitance is concerned (with either of those cables), and just go with whichever output impedance sounds better.

Although keep in mind that if your power amp's input impedance is on the low side, meaning in the range of 10K to 30 or 40K or so, the 1200 ohm setting (which probably rises considerably above that number at very low frequencies) could result in some attenuation of the deep bass. That would occur regardless of cable length. If your power amp's input impedance approaches say 75K or 100K, then I'm sure the 1200 ohm setting would be fine in that respect.

As you may be aware, that is sometimes referred to as the 10X rule -- power amp input impedance should be at least ten times greater than the output impedance of the preamp at the frequency for which the output impedance of the preamp is highest, which is usually at 20Hz, especially in the case of a tube preamp.

Regards,
-- Al

I read a lot about specs on this forum and everytime I assemble a system based on specs I walk away disappointed.

My best sounding systems used either short speaker cable and short interconnects or short speaker cable and long interconnects.

Amplifier manufacturers I have spoke with recommend short speaker wire since it transfers the power to the speakers.

I am faced with the same question in my case and need advice for the following setup:

CD: Nagra CDP
Pre amp: Nagra PLL
Amps: Nagra VPAs
Speakers: Verity Parsifal Ovation

Currently my units are all stacked near each other, leaving a 4m long speaker cable run from the VPAs to the speaker. I am about to order a Purist Proteus Provectus 4m speaker cable but didn't want to make a mistake... Would such a length have a noticeable sound degradation?

Having the amps close to my speakers is highly impractical for me but not impossible. Is it better to get 4m long RCA interconnect cables (XLR is not the best solution for my power amps) in my case and a short speaker cable(considering the specs of the Nagra pre-amp)?

In order for me to go for a long interconnect solution, the sound must be clearly better otherwise the logistics issue that will exist will not be worth the hassle. In any case, I thought that going for a such a high quality speaker cable will minimize or eliminate the negative effect of the long speaker cable run as opposed to the long RCA interconnect...

Opinions appreciated!

Well I can't imagine the price tag on the Purist cable, but maybe you should do yourself a favor and see if you can try some OCOS cable. These are only made for speaker connections and are well known to be suitable for use in long lengths. I use a 5.5m pair in my system. No degradation of sound versus shorter speaker cables I own (including a $2000 pair). If you want, you can double up on the OCOS and use two runs per speaker (not bi-wire, same binding post). This is supposed to yield even better sound. You don't hear much about this brand but it is made by Dynaudio.

Logically I would probably go with what is more cost effective and an eye on the future or heed Elizabeth's suggestion. If you ever change rooms or configurations, it might be hard to get rid of a 6 meter interconnect. Also, at this length, I personally would want to use a balanced interconnect. If my gear did not accept balanced interconnects, I would probably just go with the longer speaker cables.