The Good: The Monster SoundStage S1 is a compact wireless speaker with plenty of bass and treble. It offers a great number of connectivity options including Bluetooth, Wi-Fi and optical, plus compatibility with Spotify, Internet radio and all manner of digital files. Bass output is deep and controlled, and the soundstage is surprisingly wide for the speaker's size. The Bad: Its recessed midrange and hyped bass\/treble sound makes it a poor choice for folk and rock music. Its competitors sound more laid back and easier to listen to long term. High-resolution files can be prone to dropouts, and the app required for control can be finicky to set up and use. The Bottom Line: The Monster SoundStage S1 offers a huge, party-ready sound in a small box coupled with exhaustive connectivity, but subtle it is not. Ever since Monster lost its lucrative Beats contract, the company has seemingly struggled to find the "next big thing" to replace it. After several years of gaudy headphones and disappointing Bluetooth speakers, has the company finally struck paydirt with its SoundStage speakers? Monster is relatively late to the multiroom streaming game, trailing names like Sonos and Samsung, and it has wisely decided to partner with an open system -- Qualcomm's AllPlay -- rather than try to go it alone. At the moment, the only AllPlay products on the US market are available from Monster and , but more are promised.The Monster SoundStage S1 ($229) is Monster's smallest and least expensive multiroom speaker, but it's also potentially the best value. It generates a huge sound for its small size, and its connectivity options will ensure anyone will be able to hook it up. The larger S2 ($299) and ($399) are also available.That pricing in the US lines up closely with Sonos' Play:5, Play:3 and Play:1 series of speakers, which is pretty tough competition indeed. Monster's speaker will be available in the UK and Canada in October 2015 as the StreamCast. (No pricing available yet for the UK, but its US prices convert to \u00a3145, \u00a3190 and \u00a3253, respectively.) Meanwhile, Australian pricing and availability is yet to be announced.As far as sound quality is concerned, it's not surprising that the S1 has a "Beats" sound, given that Monster designed the . If you like like bass and crisp percussion without any of those pesky midrange distractions -- voices, acoustic instruments -- the S1 will satisfy your sonic desires. For a little over $200 it's likeable and "big" sounding but if you want something more with more accurate midrange and a classic hi-fi sound, it's not for you.DesignThe SoundStage S1 is the smallest speaker in the new SoundStage line, though it's still large for the price at 11.5 inches across, 4.9 inches high and a deceptively thick 3.5 inches deep. Though it's not designed to be portable -- there's no battery on board -- it's surprisingly heavy at 4.4 pounds.The front of the unit is quite unobtrusive with its Monster logo and black metal grille, which wraps around at the edges.Looking down on the SoundStage you can see that the main console has a pointed "lens" or "boat" shape. Touch the console and it lights up with a series of controls including forward\/back, play\/pause and volume. There is also a Wi-Fi and a Bluetooth indicator on the left and a power button on the right. Though they are ostensibly controlled by a mere touch, I didn't find them very sensitive, having to press Play several times at one point.Much like Sonos, there's no remote control included with the unit. Instead you use the AllPlay JukeBox or Monster SoundStage apps on your iOS or Android device. FeaturesUnlike the Sonos Play:1, he SoundStage S1 is a stereo speaker that features dual 3-inch drivers in addition to a passive oval bass driver at the rear of the unit. Monster doesn't include power specifications, but this small speaker is capable of going much louder than most other speakers at this price point.The S1 offers a number of different connectivity options, with the two big ones being Bluetooth and Qaulcomm AllPlay. which offers integration of numerous streaming apps as well as allowing users to play music from different devices within the home network. Its competitors include the other open standard, and Sonos' closed ecosystem. Monster is also one of the first companies to combine multiroom and Bluetooth successfully: pair your phone to one AllPlay speaker and then stream it to all of the other speakers in the house.The S1 will also play for easy access to your music without leaving the Spotify app. It also supports other services within the AllPlay app including DLNA, Rhapsody, Napster and iHeartRadio, with Tidal and SoundCloud forthcoming. There's no mention of native Pandora support at this stage, but Monster suggests using Bluetooth for unsupported apps.Other connectivity options include dual USB, optical digital and line-in. Monster says transmitting digital around the house in full quality (stereo) is planned for later in the year.On Android, the AllPlay devices are also controllable by the free DoubleTwist music player under its MagicCast feature (adding other DLNA devices attracts an $8.99 fee).If you're a fan of high-resolution music, AllPlay is one of the only systems that allows users to stream at full quality. Sonos and Denon HEOS will simply refuse to play hi-res files, while Play-Fi will downscale to 44.1\/48kHz. While it's hard to say whether the difference between CD quality and hi-res would even be discernable on a tiny system like the S1, hi-res support is more about peace of mind and compatibility at this stage. The quality differences will become more important once Monster releases its own AllPlay dongle for existing stereos in 2016.