Hypex NCx500 Class D Amplifier Review

[Sal1950]

I dunno. Make a poll? In any case: not enough of them.


I dunno. 6-7 pairs? Including fun toys like samplers and synthesizers. Around 100 euromoneys total, including lengthy ones so I can noodle around on the couch.

60 for a pair? My face:View attachment 517532
400 for cables? Ludicrous. I'll buy half a nice stereo for that kinda money!

Hey, don't squeeze him so hard, his eyeballs are popping. LOL

 

[Julf]

True, you progressively lose high frequency amplitude as the length increases.

Not really, unless you have extremely long cables and very high impedance gear (electric guitar pickups being the prime example).

 

[Sokel]

Poor Purifi went some lengths to reach the absolute (with a snake-oil flavor of course)

 

[wwenze]

It's free money from the tube amp owners, why not.

 

[TemploAztlan]

Not really, unless you have extremely long cables and very high impedance gear (electric guitar pickups being the prime example).

How many dBs down at 20kHz on a 30m coaxial cable? This can be calculated.

 

[TemploAztlan]

What lengths are we talking about here? I'd say 10 meters already counts as quite long in a home context. While all the above comments are true in principle, how much does it really matter in practice? Live audio uses dozens of meters of microphone cable sometimes, for example. Symmetric or not only benefits interference pickup either, not frequency response of the whole source-cable-sink system.

Here's some helpful info from the Audio/Video Cable Installer Pocket Guide that explains why long mic cables work:

On the other end, microphones generally have output impedances near 150Ω. This can be a dramatic difference in terms of distance and the reason why full-range micrphones can easily be installed with cables a hundred, even a thousand, feet long and still provide excellent performance.

There are even some microphones that allow the user to select the output impedance, some as low as 50 Ω. This dramatically affects distance. Because the capacitance has so little effect at these low impedances, microphone response extremely flat even over long distances.

These effects apply to balanced and unbalanced systems. Of course, professional balanced systems are almost automatically low impedance because of the distance advantage.

Home theater and consumer audio use an altogether different system.

 

[TemploAztlan]

I'd say 10 meters already counts as quite long in a home context. While all the above comments are true in principle, how much does it really matter in practice?

If your 10m cable was an electronic device like a DAC or amp, it would get a Headless Panther.

There is an equation for calculating the db loss of high frequencies but you need to know the cable characteristics like capacitance. The equation is in the Audio/Video Cable Installer's Pocket Guide though I can't find it at the moment. The author recommends staying under 27 ft. for unbalanced interconnects.

 

[Ropeburn]

Here's some helpful info from the Audio/Video Cable Installer Pocket Guide that explains why long mic cables work:

That's the same range of modern output stages that have around 100 Ohm output impedance. So yeah, it's all fine at home.

 

[TemploAztlan]

That's the same range of modern output stages that have around 100 Ohm output impedance. So yeah, it's all fine at home.

The input impedance of my amplifier is 33,000 ohms.

 

[TemploAztlan]

That's the same range of modern output stages that have around 100 Ohm output impedance. So yeah, it's all fine at home.

The original point of this discussion is that it's better to put the amp closer to the source than to the speaker. In other words, you get better frequency response with short interconnects to the amplifier input and long speaker cables. This can be proven by doing the math.

 

[boXem]

The original point of this discussion is that it's better to put the amp closer to the source than to the speaker. In other words, you get better frequency response with short interconnects to the amplifier input and long speaker cables. This can be proven by doing the math.

Curious to see the math.

 

[Ropeburn]

The original point of this discussion is that it's better to put the amp closer to the source than to the speaker. In other words, you get better frequency response with short interconnects to the amplifier input and long speaker cables. This can be proven by doing the math.

Define better. As long as the lowpass corner frequency is above human hearing, it's practically perfect and can't be improved.

 

[Ropeburn]

The input impedance of my amplifier is 33,000 ohms.

Very good. The lower the output and the higher the input impedances, the less concern all this is. You do realise that's one of the reasons these impedance relations are chosen in the first place? So you don't run into frequency response problems even with long cables?

 

[Ropeburn]

Curious to see the math.

Simplified calculator:

Calculation of cable length, cable capacitance C, and cutoff frequency cable attenuation treble loss damping microphone mic cable capacity wires XLR capacity - sengpielaudio Sengpiel Berlin

Calculation of cable length and cable capacitance C cutoff frequency cable attenuation treble damping loss microphone wire gold XLR mic cable capacity - Eberhard Sengpiel sengpielaudio

sengpielaudio.com

Put in 100 Ohm and see. Lol

I'm telling all those wondering here: it is of precisely zero concern! You'd need super long cable for a relevant effect. Hundreds of meters.

 

[TemploAztlan]

Simplified calculator:

Calculation of cable length, cable capacitance C, and cutoff frequency cable attenuation treble loss damping microphone mic cable capacity wires XLR capacity - sengpielaudio Sengpiel Berlin

Calculation of cable length and cable capacitance C cutoff frequency cable attenuation treble damping loss microphone wire gold XLR mic cable capacity - Eberhard Sengpiel sengpielaudio

sengpielaudio.com

Put in 100 Ohm and see. Lol

I'm telling all those wondering here: it is of precisely zero concern! You'd need super long cable for a relevant effect. Hundreds of meters.

OK, you're talking about balanced interconnects. As I said in a previous post, I'm taking about unbalanced interconnects. With a 15m cable, you'll lose 5 db at 20 kHz. Clearly Headless Panther territory.

 

[Ropeburn]

OK, you're talking about balanced interconnects. As I said in a previous post, I'm taking about unbalanced interconnects. With a 15m cable, you'll lose 5 db at 20 kHz. Clearly Headless Panther territory.

Show the math. Above calculator is simplified and works for both. With usual impedances and cables, there's no way you'll end up with that kinda lowpass you claim.

 

[TemploAztlan]

Define better. As long as the lowpass corner frequency is above human hearing, it's practically perfect and can't be improved.

0 dB down at 20 kHz is better than -5 db.

 

[TemploAztlan]

Above calculator is simplified and works for both.

The calculator says "

This is not about coaxial cables"

​

 

[Ropeburn]

The calculator says "

​

This is not about coaxial cables"

​

It's not about high frequency applications and coax cable used for that. Normal line and mic cable IS coaxial in construction.

I'm honestly getting annoyed at your conduct. You make a claim (-5dB at 20kHz with 15m) and repeat it, don't show math when asked, and wholesale reject presented math that proves the opposite of your claim.

Substantiate your claim and/or show how mine are wrong. Until then I'm out.

 

[antcollinet]

The calculator says "

​

This is not about coaxial cables"

​

If the capacitance, inductance and resistance are defined, the calculation will work regardless of cable construction. The maths is the same.