I did a lot of research before getting my Massdrop Sennheiser HD 6XX (a much cheaper version of the HD 650 with a more convenient cable and jack). I was fully prepared to have to buy an amp for it, as that's what everyone online says it needs. However, it plays at a very good loudness with just 50% volume from my FiiO K1 DAC. Even my iPod is able to drive it loud enough (gasp!). I don't want to listen to it at deafening levels because, well, I don't want to go deaf.
Still, so many people claim it "scales very well" with amps, that it needs an amp to get the full benefit from it, it doesn't sound as good without an amp, etc. I'd like to understand why exactly that is, with a good scientific explanation. I thought the function of an amplifier was just that: to make the signal louder, and not to improve the potential of the headphones?
I'm also very keenly aware of bias effects when listening and how even a half-decibel volume difference during blind tests on otherwise identical gear will make people subconsciously believe the slightly louder song sounds better. Since I doubt those people did proper blind testing with their amp with perfect volume matching between amp and ampless (this is extremely hard to achieve anyway without a professional decibel meter), my current hypothesis is that those people are fooling themselves and what's happening is that they're playing the music with the amp slightly louder.
I'd love to be proven wrong though, as it means I can "unlock" my HD 6XX's, which currently don't sound much better than my DT 770 Pros. Does anyone know the science behind headphone "scaling"?
Some convenient info that I remember from my head:
FiiO K1 delivers 35 mW maximum
FiiO K1 max voltage is 1.1 V
HD 6XX impedance: 300 ohm
HD 6XX sensitivity: 103 dB (1 Vrms) at 1 mW or 97 dB (SPL) at 1 mW (decided to verify this one to be sure)
As per this calculator: https://www.headphonesty.com/headphone-power-calculator/ the FiiO K1 drives my phones at a reasonable loudness level (90 dB) rather than deafening levels (110 dB) which is for some reason recommended when calculating.
Still, so many people claim it "scales very well" with amps, that it needs an amp to get the full benefit from it, it doesn't sound as good without an amp, etc. I'd like to understand why exactly that is, with a good scientific explanation. I thought the function of an amplifier was just that: to make the signal louder, and not to improve the potential of the headphones?
I'm also very keenly aware of bias effects when listening and how even a half-decibel volume difference during blind tests on otherwise identical gear will make people subconsciously believe the slightly louder song sounds better. Since I doubt those people did proper blind testing with their amp with perfect volume matching between amp and ampless (this is extremely hard to achieve anyway without a professional decibel meter), my current hypothesis is that those people are fooling themselves and what's happening is that they're playing the music with the amp slightly louder.
I'd love to be proven wrong though, as it means I can "unlock" my HD 6XX's, which currently don't sound much better than my DT 770 Pros. Does anyone know the science behind headphone "scaling"?
Some convenient info that I remember from my head:
FiiO K1 delivers 35 mW maximum
FiiO K1 max voltage is 1.1 V
HD 6XX impedance: 300 ohm
HD 6XX sensitivity: 103 dB (1 Vrms) at 1 mW or 97 dB (SPL) at 1 mW (decided to verify this one to be sure)
As per this calculator: https://www.headphonesty.com/headphone-power-calculator/ the FiiO K1 drives my phones at a reasonable loudness level (90 dB) rather than deafening levels (110 dB) which is for some reason recommended when calculating.
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