Review and measurements of MacBook Air (2024) headphone output

[ceedee]

for MacBook Air only from M2 ongoing. Surely M3 has it because I own it and it drives HD650 also very loud

I have an M3 MacBook Pro and it does well at driving the HD650, but the oratory1990 EQ correction requires a -9.3 dB preamp gain, so the perceived volume goes down quite a bit. Without the EQ applied they are pretty loud. An external amp is still needed for some music that's mastered more quietly, or when I'm doing music production with lower levels.

 

[crappypanther]

We can safely use the headphone output of modern laptops and not worry about the horror stories told to us by audiophiles

 

[visanj]

I actually wrote the driver for this headphone amplifier at Apple which was my last job there around 2020. It was done during the Covid time and I thoroughly enjoyed it just because I have some old AKG k240/K501 at 600ohm/120ohm lying around somewhere. I remembered I specifically set the max output to 4Vrms, but it became 3.2Vrms when released which was after I left, I am still curious why.

One issue was planar magnetic headphone has low impedance but requires high output voltage, I raised this issue but the consensus seems like very few customers has planar and they probably have dedicated amplifier already.

That is one heck of a job you had at Apple. I haven't communicated with anyone working in Apple's audio team before. Pleasure to be in this forum.

Back to the topic, just a question, Is headphone jack same for all MacBook Pros released after M1?

 

[stefanovesa]

Mainly because it might damage some headphone (or your hearing) considering the customer base is so big.

I think you might already noticed it in your test, the impedance detection is done at the time 3.5mm plug is inserted. In theory, you can fake it by plug a 300ohm fake load and swap it to 32ohms real headphone.

Do you know why Apple ha decided to limit to 96 kHz the sampling rate of the internal DAC? Thanks

 

[xxie]

Back to the topic, just a question, Is headphone jack same for all MacBook Pros released after M1?

I don't know the answer as I left before M1 releasing. From driver point of view, headphone jack is quite complex as so many different headphones out there (i.e. mic/button detections, different standards on pins etc), I'd be surprised if there is major change.

Do you know why Apple ha decided to limit to 96 kHz the sampling rate of the internal DAC? Thanks

The audio routing inside the computer could be fairly complex, i.e. you might need share same audio bus for different devices; there might be also signal integrity concern too. I imagine a dedicated DAC has no such concern and able to reach 192khz.

 

[amper42]

Do you know why Apple ha decided to limit to 96 kHz the sampling rate of the internal DAC? Thanks

Apple didn't want to pay the tariff on frequencies over 96kHz.

 

[stefanovesa]

Apple didn't want to pay the tariff on frequencies over 96kHz.

LOL