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Van Damme Interconnects: Pro Grade Classic XKE vs Up-LCOFC Hi-Fi Twin

ToTo Man

ToTo Man

the band not the dog
I need to order interconnects for my tape decks, each run will be 5 or 6 metres.

The single-ended side of my hifi has been wired up with Pro Grade Classic XKE Instrument for the last decade or so. I chose this as it's a no-nonsense cable that's affordable and well regarded, but this was before I was aware of the impact of resistance and capacitance.

Van Damme also sell a UP-LCOFC cable that's marketed for consumer hifi which has 1/3rd the resistance of the Pro Grade XKE (30Ω/km vs 90Ω/km) and slightly lower capacitance (77pF/m vs 90pF/m).

I'd like to know if there is likely to be any audible difference in performance between these two cables when used in >5m runs?

More generally I'm also interested to know how many forum members use Van Damme UP-LOFC interconnects in their system as it doesn't appear to be as popular a product as their XKE series (perhaps because it's significantly more expensive?).
 
I use Van Damme in my PA set up extensively. It’s good stuff, all be it the connectors are all balanced. I use their microphone cables, and the recordings seem very quiet in a positive way.

I also use Van Damme speaker cables for my surround, and have had no issues. That is the extent of my experience with this brand.

Can I claim my £5 for contributing to your thread?:D
 
The change in resistance will be so small as to be completely imperceptible - half an ohm into what? 10K, 22K, 100K?

The difference in capacitance is likewise quite small but the effect more dependent on the source impedances and input impedances involved. No audible difference I would expect.
 
Barrymagrec said:
The change in resistance will be so small as to be completely imperceptible - half an ohm into what? 10K, 22K, 100K?

The difference in capacitance is likewise quite small but the effect more dependent on the source impedances and input impedances involved. No audible difference I would expect.
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This is what I was hoping the answer would be as the UP-LCOFC is dearer than the Pro XKE (as would be expected of course, given its higher copper content). Sticking with the XKE would save me some dosh.
 
ToTo Man said:
I need to order interconnects for my tape decks, each run will be 5 or 6 metres.

The single-ended side of my hifi has been wired up with Pro Grade Classic XKE Instrument for the last decade or so. I chose this as it's a no-nonsense cable that's affordable and well regarded, but this was before I was aware of the impact of resistance and capacitance.

Van Damme also sell a UP-LCOFC cable that's marketed for consumer hifi which has 1/3rd the resistance of the Pro Grade XKE (30Ω/km vs 90Ω/km) and slightly lower capacitance (77pF/m vs 90pF/m).

I'd like to know if there is likely to be any audible difference in performance between these two cables when used in >5m runs?
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As @Barrymagrec writes the series resistance of the cable will be completely insignificant for realistic runs like 10 metres. And as he writes, for capacitance it depends on the output impedance of what drives the cable.

Solid-state consumer audio kit should not really have an output impedance above 1,000 Ohms (although some valve kit might). Audio roll-off starts to get significant (3 dB) at Fmax = 1 / (2 * pi * R * C). With a little bit of hand-waving, for no audible roll-off you need Fmax > 100 kHz ( 5 * 20 kHz).

So for a worst-case 1,000 Ohm output impedance the cable capacitance should be less than 1,600 pF. That's a maximum of 18 metres at 90 pF/metre so I don't expect any real difference between the two options. And if the output impedance were a much better 300 Ohms or less the cable could be three times longer.

Do check the actual output impedance if possible. And do check that the 90 pf/metre is the entire capacitance. I use star-quad for balanced connections of about 5 metres and the conductor-to-conductor capacitance that is specified is far from the complete story when it comes to total cable capacitance. However I have an output impedance specified as 20 Ohms so it's fine.
 
John Phillips said:
As @Barrymagrec writes the series resistance of the cable will be completely insignificant for realistic runs like 10 metres. And as he writes, for capacitance it depends on the output impedance of what drives the cable.

Solid-state consumer audio kit should not really have an output impedance above 1,000 Ohms (although some valve kit might). Audio roll-off starts to get significant (3 dB) at Fmax = 1 / (2 * pi * R * C). With a little bit of hand-waving, for no audible roll-off you need Fmax > 100 kHz ( 5 * 20 kHz).

So for a worst-case 1,000 Ohm output impedance the cable capacitance should be less than 1,600 pF. That's a maximum of 18 metres at 90 pF/metre so I don't expect any real difference between the two options. And if the output impedance were a much better 300 Ohms or less the cable could be three times longer.

Do check the actual output impedance if possible. And do check that the 90 pf/metre is the entire capacitance. I use star-quad for balanced connections of about 5 metres and the conductor-to-conductor capacitance that is specified is far from the complete story when it comes to total cable capacitance. However I have an output impedance specified as 20 Ohms so it's fine.
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According to my Yamaha A-S3000 manual: "Rated Output Voltage / Output Impedance: REC OUT = 200 mVrms / 1.5 kΩ"

So, if I wanted 0dB (or essentially 0dB) loss at 20kHz, what would be the maximum pF/m I could get away with?

Regarding Van Damme's capacitance specs, I did wonder why they quote a single value for the XKE and UP-LCOFC interconnects but two values (conductor and screen) for the star quad interconnects. I'm presuming the single values quoted for XKE and UP-LCOFC represent the total capacitance and are therefore comparable between the two cables?
 
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ToTo Man said:
According to my Yamaha A-S3000 manual: "Rated Output Voltage / Output Impedance: REC OUT = 200 mVrms / 1.5 kΩ"

So, if I wanted 0dB (or essentially 0dB) loss at 20kHz, what would be the maximum pF/m I could get away with?
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For the 1.5 kΩ output impedance, a cable with 1,000 pF total capacitance would have a roll-off of about 0.15 dB at 20 kHz which I bet no-one would notice. Even 1,850 pF total would just have 0.5 dB loss at 20 kHz. So choose the maximum length according to the cable's total capacitance per metre and your tolerance for the 20 kHz loss.
ToTo Man said:
Regarding Van Damme's capacitance specs, I did wonder why they quote a single value for the XKE and UP-LCOFC interconnects but two values (conductor and screen) for the star quad interconnects. I'm presuming the single values quoted for XKE and UP-LCOFC represent the total capacitance and are therefore comparable between the two cables?
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On the first question the capacitance value(s) that matter in reality will depend on exactly how you connect the cable, so having the specification broken down is useful. On the second question I assume this too.
 
I ran some basic sine wave tests to compare the signal loss from a 1m length of Van Damme Pro XKE and a 6m length (the 6m length was actually 1m and 5m lengths joined with a gold-plated RCA coupler to save the hassle of going round the back of my amp to change leads!**).

Compared to the single, unjoined 1m length, the additional 5m of cable causes a loss of:
-0.108 dB @ 23.5kHz
-0.079 dB @ 20kHz
-0.051 dB @ 16kHz
-0.016 dB @ 8kHz
-0.007 dB @ 4kHz
-0.005 dB @ 2kHz
-0.004 dB @ 1kHz
-0.003 dB @ 500Hz
-0.004 dB @ 250Hz
-0.008 dB @ 100Hz
-0.007 dB @ 50Hz
-0.004 dB @ 30Hz
-0.003 dB @ 20Hz
-0.003 dB @ 10Hz
and an increase in noise floor of 0.54dB (1m = -91.665 dB, 6m = -91.127 dB).

(** I repeated the test with two 1m Pro XKE joined together just to make sure the RCA coupler wasn't making a significant contribution to the signal loss, There was very little difference in the loss between the two joined 1m lengths and single 1m length).

So for a tape in / tape out loop consisting of two runs of 5m Pro XKE, I'd expect the losses to be double those above (assuming the input/output stage of the tape deck behaves similarly to the output/input stage of my amplifier and A/D converter).

In short, I don't expect any of this to be audible, especially given that I failed to score 100% accuracy in a blind-test that compared Chord Hugo 2's two oversampling filters which, according to my measurements, changed output at 20kHz by almost -1dB.
 
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