Why you can't trust audio measurements

[J.A.F._Doorhof]

Daar is een zeer technische verklaring voor.

[chansig]

Nou, kom maar op.

Gr. Hans

[morca]

Ik heb er 1 van 2 meter.
Ik hoor geen verschil tov andere van 1,25 meter.

[J.A.F._Doorhof]

Voorop gesteld
PERSOONLIJK zit ik in het kamp dat voor de zekerheid op de eind en voorversterkers standaard goede 1.8 mtr kabels heb zitten. Kwamen toen uit eigen voorraad

De uitleg qua shielding is te verklaren.
Maar voor de rest is alles hier ook zo kort mogelijk maar wel heel goed gescheiden van signaal kabels.

Dit is de ai uitleg.
Laatste deel gaat erg richting commercie eerste deel mag iemand met meer verstand van stroom op reageren. Het lijkt mij stug dat iemand dit hoort.

In high-end audio systems, some manufacturers and enthusiasts recommend a minimum power cord length—typically around 1.5 to 2 meters (about 5 to 6.5 feet)—to optimize performance.

This stems from the idea that well-designed power cords incorporate shielding and filtering to reduce electromagnetic interference (EMI), radio frequency interference (RFI), and noise that could affect sound quality.

Shorter cords may not allow these features to function as effectively, potentially leading to degraded noise rejection or restricted power delivery, which could make the audio sound thinner or less dynamic.

Additionally, cable length influences conductor resonance; at around 2 meters, it reportedly resonates in a broader, smoother manner compared to shorter (e.g., 1-meter) lengths, contributing to perceived improvements in soundstage, separation, and overall fidelity.

 However, this is specific to premium aftermarket cords—standard stock cords often perform better when kept as short as possible to minimize resistance and voltage drop.

[gastje13]

However, this is specific to premium aftermarket cords—standard stock cords often perform better when kept as short as possible to minimize resistance and voltage drop.

Dit geeft eigenlijk al aan dat het onzin is, misschien iets ander materiaal aan isolatie of zilver i.p.v. etc maar de basis dat korter = minder weerstand en minder potentieel instralingsoppervlakte blijft gewoon gelden. Eventueel breedbandigere afscherming lijkt me (als dit al van invloed is) eerder te realiseren met dikkere geleiders/mantels dan langere. Dikkere antennes zijn namelijk ook breedbandiger dan dunner. De lengte bepaald de optimale resonantie frequentie. Niet te vergeten alle tientallen meters tot aan de transformator zonder de kabel verlengd.

Voor de fun: ik heb het ook eens aan AI / ChatGPT gevraagd:
(het advies helemaal onderaan is wellicht het meest waardevol . .)

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The claim that a 1.8-meter power cable sounds better than a shorter one (or that it's a kind of "magic length") is a well-known audiophile myth, and while it's popular in some high-end audio circles, it's not supported by solid electrical engineering principles.

Let's break this down into the facts, the myth origins, and the reality.

✅ The Electrical Facts

Power cables to audio equipment (like amplifiers, DACs, or turntables) carry AC mains power, typically at 50/60 Hz. Key facts:

The power supply inside the device is what ultimately determines how clean and stable the power is.

Cable length (within a few meters) makes almost no measurable difference in voltage, resistance, inductance, or noise rejection at those frequencies.

For typical household power, a difference of 0.5m–2m is electrically insignificant — resistance and impedance changes are negligible.

📜 Where the 1.8m Myth Comes From

There are a few possible sources:

Marketing Convenience: 1.8 meters (about 6 feet) is a common, practical cable length. It's long enough to reach most outlets without too much slack. Some companies may have arbitrarily declared it "optimal" to sell cables with a story.

Mains Noise/Interference Theories: Some enthusiasts believe a certain length of cable might help "tune" or dampen electromagnetic interference (EMI) or radio frequency interference (RFI) better than a shorter one. But this is highly speculative, and not backed by reproducible measurements.

Resonance/Standing Wave Folklore: There are internet theories claiming that certain cable lengths "match" some kind of harmonic or standing wave in the power system. These are not scientifically sound in the context of 50/60 Hz AC and consumer-grade equipment.

🎧 The Perceived Sound Difference

Many audiophiles report hearing improvements with specific cable lengths, including 1.8m. Possible explanations:

Expectation Bias / Placebo: If someone believes 1.8m sounds better, they may perceive it that way.

Build Quality Differences: A 1.8m high-end cable may be better shielded or constructed than a shorter generic one, which can reduce noise if the system is very sensitive to interference (especially with poorly grounded gear).

System-Specific Factors: In very specific setups (e.g., poorly designed components, noisy power), any change might make a small difference — but this is not due to length alone.

🧪 What Audio Engineers and Physicists Say

No credible peer-reviewed evidence supports the idea that 1.8 meters is a special or optimal length for power cords.

Professional audio engineers usually prioritize proper grounding, shielding, and clean power sources (like power conditioners or isolation transformers) over cable length.

🧾 TL;DR

📏 1.8m is not a magic number — there's no physical or electrical reason it's better than a shorter or longer power cable.

🎧 If you think it sounds better, it might be due to subjective perception or better cable build quality, not the length itself.

🧠 If you're chasing better sound, focus on component design, room acoustics, speaker placement, and clean power, not power cable length.

Would you like a suggestion for actual measurable upgrades you could make in your audio chain?

[J.A.F._Doorhof]

Vandaar dat ik zeg het is te verklaren maar het lijkt me stug dat je het hoort. Met zoveel van die kabel discussies, waar ze over spreken zijn zo minuscuul of niet te meten dat er zat andere verklaringen zijn.