Monster Bluetooth speaker S520

A small speaker is easy to bring along, but outdoor listening can be less convenient when rain, splashes, or frequent recharging are concerns. The Monster S520 is built around portability, wireless playback, and an IPX7 water-resistance rating.

Its lanyard gives you a way to hang it from a backpack or bike, rather than having to find a flat spot for it.

It also has a built-in microphone for calls and can pair with a second identical speaker for left-right stereo. The main trade-off is that the listing gives no speaker dimensions or charging time, which makes it harder to judge how it will fit your routine.

Technical details

The S520 is a portable Bluetooth speaker with a built-in microphone, a lanyard, a Type-C charging port, and an IPX7 rating. Bluetooth 6.0 is listed, along with a wireless range of up to 50 feet. Battery life is stated as up to 12 hours, so treat that as a maximum rather than a guaranteed runtime for every volume level or situation.

The water-resistance detail is more specific than a general “outdoor” label: the product description says it can be submerged up to 3 feet for about 30 minutes. That may suit a rainy campsite or a speaker near the shower, but it is still worth handling it as a portable speaker rather than assuming every water-related situation is covered. The runtime and waterproof claims are according to the maker.

What it works with

The speaker is designed to connect to Bluetooth-enabled devices. That covers wireless music playback from a compatible phone or other Bluetooth source, the product details do not name particular devices or operating systems. Its microphone also supports hands-free calls over Bluetooth, which is useful when your phone is tucked into a bag while you are outside.

For a wider stereo image, the S520 supports TWS pairing with a second identical Bluetooth speaker. This is a different approach from buying one larger speaker: two units can create left-right channels, but that means choosing and setting up a matching second speaker. If you only need sound from one compact unit, the single-speaker setup is simpler.

Usage tips

Clip or hang the speaker from a backpack or bike using its lanyard when keeping a clear spot on a table is inconvenient. At a picnic, for example, you can leave the table free for food and keep the speaker nearby for music. Bluetooth’s stated range is up to 50 feet, though walls, placement, and the connected device may affect a real-world connection.

Use the Type-C port for charging, and consider whether the stated maximum of 12 hours suits the length of your outings. The description does not provide charging time, dimensions, or weight, so those details may matter if you are packing light or need to plan a quick top-up. It suits you if you want one compact speaker for everyday listening, calls, and outdoor settings. It might not be a great match if you need documented size and weight figures or a more demanding stereo setup without adding a second unit.

Practical doubts

Can it be used around water? The listing gives it an IPX7 rating and specifies submersion up to 3 feet for about 30 minutes. Follow that stated limit rather than assuming unlimited underwater use.

Can it play in stereo? Yes. TWS lets it pair wirelessly with a second identical speaker for left-right stereo.

Can you take calls through it? The built-in microphone is listed for hands-free Bluetooth calls. Call performance details are not provided.

Should you buy it?

Choose the Monster S520 if a lanyard-equipped speaker, Bluetooth playback, and a stated IPX7 rating fit how you spend time at home or outdoors. Its call microphone and optional pairing add flexibility without requiring a two-speaker setup from the start. Skip it if your decision depends on exact dimensions, weight, charging time, or verified performance beyond the claims in the listing, those specifics are not supplied here.