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Argus25 · 14th Oct 2017, 4:39 am

I wouldn't try to defend a lot of the Phoolery that goes on in the audiophile industry, but sometimes I think we should be more forgiving.

For example, in some areas, not so much HiFi, but in the field of instruments and amplifiers, the cable types, and lengths of cables have a very large effect on the frequency response and sound.

One reason for this is the Hi Z output impedances of guitar pickups and the controls used. Since the impedance is high, usually well over 100k depending on the control positions, then the coaxial cables leading to the amplifier have a big effect, a few meters or more can be over 500 to 700pF. So musicians notice this changes the sound. So it becomes common knowledge that "The cable affects the sound" This gets generalized to other scenarios, where the source impedance is very low, and the cable capacitance is now having negligible effects, but it is still assumed "the cable affects the sound" so you can understand why people end up thinking this way.

Long cables between magnetic phono cartridges can also have some high frequency roll off effects.

The world would be wonderful if all signal outputs from every device/instrument were low Z and better still matched to the cable impedances and we could forget about cable characteristics, but that is not reality.

When early electronic effects like treble boost amplifiers were added to guitars, to lift the high frequency harmonics, one method of controlling it was just to put a series 500k pot with the output of the guitar. This formed an LPF with the cable capacitance that the musician could adjust. The effects of this are very significant.

Have a look at the Spice simulations in this article looking at the behavior of a simple single transistor treble boost amplifier that Gretsch fitted to some of their guitars in the 1960's that used this idea, without the cable capacitance it would not work properly:

http://worldphaco.com/uploads/Gretschdoc.pdf

So it must be awfully hard for non technical people to figure out what makes sense, when sometimes a remark about an audio related part, a cable, a valve, a capacitor etc is made and if its likely to be correct or just nonsense.

What is really happening here is that the customers in this industry are being taken advantage of by companies using known marketing techniques to pull the wool over their eyes, it (the marketing claims made) probably should be illegal and we should go easy on the customers.

14th Oct 2017, 4:39 am	#150
Argus25 No Longer a Member Join Date: Oct 2016 Location: Maroochydore, Queensland, Australia. Posts: 2,679	Re: Audiophoolery. 'Cable Break In' - I never knew that! I wouldn't try to defend a lot of the Phoolery that goes on in the audiophile industry, but sometimes I think we should be more forgiving. For example, in some areas, not so much HiFi, but in the field of instruments and amplifiers, the cable types, and lengths of cables have a very large effect on the frequency response and sound. One reason for this is the Hi Z output impedances of guitar pickups and the controls used. Since the impedance is high, usually well over 100k depending on the control positions, then the coaxial cables leading to the amplifier have a big effect, a few meters or more can be over 500 to 700pF. So musicians notice this changes the sound. So it becomes common knowledge that "The cable affects the sound" This gets generalized to other scenarios, where the source impedance is very low, and the cable capacitance is now having negligible effects, but it is still assumed "the cable affects the sound" so you can understand why people end up thinking this way. Long cables between magnetic phono cartridges can also have some high frequency roll off effects. The world would be wonderful if all signal outputs from every device/instrument were low Z and better still matched to the cable impedances and we could forget about cable characteristics, but that is not reality. When early electronic effects like treble boost amplifiers were added to guitars, to lift the high frequency harmonics, one method of controlling it was just to put a series 500k pot with the output of the guitar. This formed an LPF with the cable capacitance that the musician could adjust. The effects of this are very significant. Have a look at the Spice simulations in this article looking at the behavior of a simple single transistor treble boost amplifier that Gretsch fitted to some of their guitars in the 1960's that used this idea, without the cable capacitance it would not work properly: http://worldphaco.com/uploads/Gretschdoc.pdf So it must be awfully hard for non technical people to figure out what makes sense, when sometimes a remark about an audio related part, a cable, a valve, a capacitor etc is made and if its likely to be correct or just nonsense. What is really happening here is that the customers in this industry are being taken advantage of by companies using known marketing techniques to pull the wool over their eyes, it (the marketing claims made) probably should be illegal and we should go easy on the customers.