Ortofon Per Windfeld Load Impedance?

First, my apologies for this thread going OT...

Zieman, perhaps a discussion of cables is appropriate here.

Cables have what is known as 'characteristic impedance'. This value is an impedance such that when the cable is terminated with this impedance, there will be no reflections in the cable. The characteristic impedance of any cable is a combination of its resistance, capacitance and inductance, plus dielectric constants, lead spacing and geometry. The formula for predicting this value is a bit tricky, and measuring it is best done on a Time Delay Reflectometer.

The place where this cable quality really comes into play in audio is speaker cables, not so much interconnects. There is a termination standard in place for balanced line (600 ohms) but for single-ended there really isn't a standard (although single ended cables would benefit from one). This lack of a standard causes single-ended cables to exhibit audible artifacts, which has given rise to the high end audio cable industry, and is the primary reason we decided to produce what was at the time the first balanced line preamplifier for home audio.

The termination of the cartridge at the input of the preamp will also take care of most cable issues. The reason I stress doing the loading properly is I have seen audiophiles compensate for a bright amplifier, amp/speaker mismatch, poor room acoustics and the like by messing with the cartridge loading. The problem is, you can't get it right and the result is often blamed on other equipment which is not at fault.

You can set the load for the cartridge by ear- to do so, you need a variable resistance across the input of the preamp, which starts out very high. It is then decreased (noting that there will be less high frequency energy as this is done). If any change in volume is detected you have gone too far. This is a less accurate technique but IME I have not seen the cable play a role in the final value.

Ralph's point about characteristic impedance is a very important one. IMO, it is another reason why some cables sound different from others and why cables that sound good in one system may sound awful in other systems. I have found for example in my system that low characteristic impedance (<10 ohms) is very important for good sonics. I think this is why Nordost cables, the early ones of which had very high characteristic impedance, were just unbearable in my system, so bright they could make my ears bleed, as the saying goes. Characteristic Z is independent of cable length, by the way.

Independent of length? How come some cable mfgrs change geometry at different lengths in the same model? Res, cap, and ind, are per foot or whatever measure, yes? Surely you lose more than volume (not the word I want) as length increases, particularly with so little to drive it? Like a low output MC. Cartridges that were developed AFTER Fail learned everything... Go slow and use little words please. I read the white papers, I didn't say I understood them...

Amplitude, surely you lose more than just amplitude at longer lengths?

Zieman, the traditional problem with long interconnects is loss of high frequencies. I say traditional because the case of a low output moving coil is a special case. The source impedance of the cartridge is very low- often only a few ohms. Although they don't make much **voltage**, they do make quite a lot of **current**, else it would not be possible for one to drive a 100 ohm load with no loss of output. Try doing that with a tube preamp (the only one I know of that can do that is our own MP-1...)!

So- this is what you have to understand: **There will be no loss in volume, even if the cable is 50 feet!** The source impedance of the cartridge will be unperturbed by the very slight resistance of only a couple of ohms presented by a long cable. The load of the cartridge remains the important variable, and it is here that you will likely hear more difference on account of the quality of the resistor than you will the cable.

You will also hear changes that have little to do with the cable- just pulling the cable out of the back of the preamp and plugging it in again can result in a change if you have any corrosion on your connectors (gold notwithstanding...), plus minor changes that resulted from your messing with the connection at the base of the arm.

This is one of the reasons I like the Triplanar- the only connection is at the cartridge (no removable headshell) and at the preamp- the cable is integrated. The variables of connections are eliminated.