Due to some issues with the previous model, I recently had my 2014 era Retina MacBook Pro (model identifier 11.3) replaced with a 2015 model (identifier 11.5). This wouldn’t ordinarily be a logical upgrade; given that the 2 machines share the same case design and many of the same features, minus the force touch trackpad and a few hardware upgrades including new Intel CPUs, a faster AMD R9 GPU and a faster flash storage drive.
Of course, the first step when setting up a fresh computer is to install your applications; for me, that included nearly 100GB of instruments and plugins, not to mention ProTools, Logic, and many other apps that I use on a day-to-day basis. While waiting for those apps to install, I opened my iTunes library; and was greatly surprised by what i heard.
I honestly can’t say I ever found the performance of the audio hardware in the 2014 MacBook Pro to be even remotely lacklustre; in fact, as far as built-in audio hardware goes, I’d say it’s up there with the best. It was certainly good enough for late-night iTunes sessions where connecting and powering up the hi-fi wasn’t at all appealing.
This model employs the same Cirrus Logic 4208-CRZ low power HD audio codec that Apple have used for a number of their machines; including the 2013 and 2014 MacBook Pros, and some of the MacBook Air models. Similar to the CS4207, this 6-DAC chip supports sampling rates of up to 24-bit, 192KHZ (96KHZ on the input) and offers a headphone amplifier with a 44MW/16 ohm output per channel.
I connected up my usual day-to-day phones (a pair of Sennheiser HD202s). I love these headphones because not only are they supremely durable and able to stand up to daily usage, but they sound fantastic with just about anything from an MP3 player to a dedicated headphone amplifier. The Mac had no problem, however, running a pair of HD650s at decent levels.
I’m unsure exactly what Apple have changed in this model; however I can say that the sound is infinitely superior to that of the previous model. Immediately, I noticed a huge sound stage with a beautiful stereo image. The power is also far greater; and the sound is cleaner. It’s obviously not going to rival a dedicated amplifier in terms of the sound levels it can produce; and it still sounds, perhaps, somewhat thin in comparison to a dedicated amp such as Acoustic Research’s UA1.
Perhaps the biggest difference, however, was the complete lack of any discernible noise. Even at maximum volume, being fed by a tone far beyond the reach of human hearing (so as to prevent the the amplifier shutting down to save power), the internal headphone amp produced no noticeable hiss or extraneous noise. And that, in itself, is impressive; especially given that many dedicated amplifiers aren’t so quiet.
Maybe it has something to do with power supply regulation. Or maybe one of the revised components leaks less noise into the system, resulting in better sound quality. Whatever the case, sound quality is one of the 2015 MacBook Pros biggest virtues. I bet nobody was expecting that.