One of the best features of the MS-AK mods is the removal of the software-tied volume pot, which ridiculously calls to action the touch screen. MS-AK mods add hard stops to both minimum and maximum volume settings. No more interference from the touchscreen. A simple eyeballing of the nipple on the volume pot will show you where on an analogue scale the volume is set.
Inexplicably, the original AK100 and AK120 have nipples, but lack hard stops.
What in the hell were iRiver thinking? Visual cues overriding blind interfaces is poor programming/engineering. If you’re a user of the original AK100 and AK120, you’ve probably accidentally blasted your poor ears whilst plumbing your album queue for John Denver after barely tapping the bloody volume pot. The MS-AK mods do away with that.
Second, both mods add balanced output. These are line outs, not headphone outs, so it is necessary to own a balanced amp to enjoy the upgrade. Third, at a 100% turn of the volume pot, signal amplification is removed, giving a pretty damn accurate rendering of line-level output.
In effect, Mezzo Hifi’s modifications remove much of what made the AK series a joke. They add what I feel are the bare necessities of a high-end portable audiophile device: noiseless outputs, and high current to low-Ω loads. To that, they add balanced output and remove the ridiculousness of blind interface volume calls.
If you bought the AK100 or AK120 because of its decent battery life, you may be miffed. MS-AK mods do a hell of a lot of good. But the do so at the expense of battery life. The prototypes got by with like 10 hours of battery life. Production units manage 12 to 16 hours- John Denver dependent.
And if you’re a frequent pocketer, you may nudge the volume control up or down. Gone is the software volume lock. I’ve had very little problem with that, but then I’m just one dude with a very small selection of jeans. Beware: when you adjust the volume, voltage increases after a small delay. If you nudge the pot up, it won’t be too loud for about a second or so. Then, WHAMMO! Ditto when you nudge it down.
The short: be careful. Jus like when you pocketed your iPod/iBasso amp you had to be careful with the analogue volume pot, you will have to be careful now. Of course, the sound is now much better than it was then. We have come full circle.
Ironically, that circle is complete with iRiver’s first, and now abandoned, AK device.
Sean Chan’s brown paper bag changed my life. I had accepted that so-called audiophile devices to be riddled with problems, and therefore, to be skipped as rubbish extravagance. Mezzo Hifi’s MS-AK upgrades do away with some of the worst interface design this side of auto-squirting bidet, and produce sound quality that no portable amp, and no portable DAC at any price can come close to approaching. They add functionality, and do so in a tight and orderly package.