I just received the Mixamp Pro 2013. Here are my first impressions. This is by no mean a proper review. Those have been done by people much more qualified than myself on this forum. I'm just sharing my impressions for those who are interested in this thread.
Out of the box
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The packaging is nice, sturdy and well designed. I really appreciated that all the necessary cables were included and were of reasonable quality. The instructions are short and clear.
Astro really had the average gaming systems in mind. The USB 2.0 and the TOSLINK cables included were measured at 10 ft. That means I can connect the Mixamp Pro to my (soon coming) PS4 and place it next to me on my sofa to control the volume without having to standup. It's a very nice and important touch. After all, video gaming is the national sport of the couch potato association. On a side note, I like that the USB cable is slightly pliable, which makes cable management a little bit easier.
There's but one criticism. I just wish the splitter would look a little sturdier. It's the thinnest and seems like the weakest cable of those included. Time will tell if this is really an issue.
First inspection of the Mixamp Pro
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I really like the build quality and design. The material at the bottom (some soft plastic) sits well and makes sure the unit doesn't slide. The inconvenient is that it's going to gather dust quickly. I like the feel of the knobs. The master one is big and has a good amount of resistance so you can adjust the setting piecemeal. The game/voice knob is a little looser, but still well made and the little guide helps find the middle very quickly. Finally, the three buttons (on/off, dolby and eq mode) have a good clicky response. You won't push them by accident and you'll know you have pushed them because of the feedback they provide.
The ports on the device seem solid enough. They aren't too hard to maneuver. One could remove a headset single handedly for instance. You may need your two hands to plug something and keep the device steady though. The ports don't seem too fragile either. Time will tell if they resist a lot of plug in and out action.
First use of the Mixamp Pro
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I must warn that my Fidelio X1 are coming at the end of the month and in the absence of proper headsets, I won't be able to judge the sound quality. I'll have a go, but it'll be a very superficial and incomplete opinion.
The first thing I did was connect the Mixamp Pro to my MacBook Air 2013 using the USB port and downloaded the firmware upgrade off the
manufacturer's website. I had to right click the installation file and select open to bypass Mavericks's security as the file was not properly signed. That's very surprising for a firm of Astro's caliber. Even more disconcerting was the fact that the file refused the start and just crashed. This is outright shameful. I couldn't find anything on the forum or the knowledge base regarding this issue. I left a message to the technical support team. I'll let you know what happens.
There's one major UX flaw. When the on/off, Dolby or the eq buttons are on, a red ring encircles them and when they are off, a white ring circles the on/off switch. This is at first confusing. After all, red usually means off or stop and white or green usually means on. Surprisingly, the colors on the box are orange, not red, which seems to indicate that at some level, someone thought the red was a bad decision. I get that the astro color palette uses red, but as an interface, this is unintuitive. What is even more unintuitive is the eq modes signaled by a quarter light. Go figure which mode corresponds to which light. The manual is useful and ultimately you'll use one and won't change it, but still, not the best UI. I'm actually questioning the need for the EQ button that doesn't seem to do much in the way of sound anyway. Those issues are far from deal breaker flaws. You'll learn quickly, obviously, but this is just bad design decisions.
The MacBook Air 2013 doesn't have the TOSLINK connection of the MacBook Pro Retina. However, using the USB port is enough to have the Mixamp Pro recognized. There was a big amount of hissing at mid to high volume, but overall I did find the bass to be clearer and more powerful. The mids were brighter and the overall sound was a definite improvement. Again, for a more comprehensive review on sound quality, please refer to other posts on this forum.
Every so often, the signal coming through the USB port got a lot of parasites. The noise was very strong and grizzly. It necessitated that I unplugged the USB cable and plugged it back. It may have something to do with my machine. I have the power cord on, the Thunderbolt cable and two USB hubs, so there's a fair bit going on, but this is not pleasant. However, my main use of the Mixamp Pro is for a PS4, so it doesn't really matter (as long as the problem is not found on the console). Furthermore, Astro recommends using the Mixamp Pro with a TOSLINK cable when plugged to a PC, so I don't know if I can really fault them for that.
Edit: I was able to upgrade the firmware using another Mac. The technical support didn't give me a reason for the problem. As for the buzzing noise, I've since found out it happens sometimes when using the USB cable for both power and signal. The problem only manifests itself when I'm using iTunes and goes away when I switch output device and then select the Mixamp Pro again. It doesn't happen if I use the 3.5mm cable to transmit sound from my Mac to the amp.