The SP1 is a super-compact product. The design of both the SP1 and its box is kept simple, which is great.
Bundle-wise, you get what is needed for the device to function, but there is no included USB charger, only a USB cable to charge it through your PC. Both cables are of really good quality.
a.m.p's SP1 looks great in black and red. The exterior of the SP1 is really well-made, and so are its buttons. All interfaces are located on a rubber belt that goes the entire way around the device. The rubber is really thick, giving the unit a nice and secure footing on pretty much any surface while also protecting it from harm, to some extent. Despite looking totally rectangular to begin with, the SP1 actually features some odd angles; you will definitely notice that the entire design slants backwards a bit, which helps with natural sound dissipation, after putting the SP1 on a level surface for the first time.
You can hook the SP1 up via either a mini-jack cable or Bluetooth, but sound quality is best when used with the cable because Bluetooth compresses the signal. With just a small amount of noise in the room, you cannot hear the difference due to the limits of the amplifier and units inside the SP1. They have definitely overcompensated for the sound quality achievable via Bluetooth with their amplification stage and drivers.
Design-wise, the SP1 is brilliant. On top of the device are three buttons that allow you to adjust the volume and stop/resume what is playing. The button setup feels sufficiently rugged to handle normal day-to-day abuse. The device also has no sharp corners and is wrapped in thick rubber. The enclosure's interior also looks well made.
The a.m.p SP1 is roughly the same size as the UE BOOM, and they have a very similar feature set. The primary difference between the two is in their shape: the UE BOOM is cylindrical and the SP1 is more boxy. Besides being shaped differently, the SP1 is also $110 cheaper than the UE BOOM. The only trick the UE BOOM has up its sleeve is its ability to be used in tandem with another UE BOOM. We tested the two devices against each other directly, one BOOM vs. one SP1—all sound enhancements and EQ were turned off and listening conditions were matched, within reason. We used the Samsung Galaxy S3 International Edition for all our tests, and all source materials were high-quality, FLAC-encoded files.
Both units look quite attractive with the UE BOOM having a slight edge due to the material choice being a bit more extravagant. Sound-wise, the two are quite close, at very low volume and via Bluetooth, but the UE BOOM clearly maintains better control once you increase volume. The SP1 distorts quite a bit toward the upper end of its volume range, which is not a major issue if you plan on using the device at home, but you would want the extra volume to drown out unwanted background noise outside. Sound projection on the SP1 fares well when you stand close to the unit, but the UE BOOM has a major advantage in bigger rooms.
When it comes to clarity, the SP1 does alright when hooked up via the mini-jack cable. Its sound quality is comparable to the UE BOOM at low volume levels, though with a slightly more mid-centered and less natural sound. On Bluetooth, the UE BOOM looses less performance than the SP1, which is perhaps due to the UE BOOM using a more elaborate on-board DAC system. Both have sufficient sound quality via Bluetooth to be entertaining on the go, and the SP1 is the easier device to take with you because a box-shaped solution is much easier to pack down. The SP1 is also slightly easier to clean because it has an all-plastic and rubber exterior, so there is a trade-off between looks and ease of maintenance here.
The SP1 delivers the 10 hours of battery life a.m.p promised, but how long it lasts greatly depends on volume and whether or not it is used via Bluetooth or mini-jack cable. Compared the UE BOOM, these five hours less are quite a bit, especially if you plan on taking the SP1 along on trips were wall outlets are few and far between.