Monster S620 Review: Waterproof Portable Power

Who Should Buy It

Key Specifications

Overview

The Monster S620 is a portable Bluetooth speaker positioned for outdoor and travel use. The listing emphasizes a 60 watt output, IPX8 waterproofing, and true wireless stereo pairing for a budget price. Monster states the design was crafted by Noel Lee and the Monster team with 40 years of audio experience. This background suggests the speaker is intended to offer a step above generic no name portables.

Published specifications include Bluetooth 5.4, a TF card input, two EQ modes, and a cylindrical body measuring 8.59 by 3.29 by 3.29 inches. The speaker weighs 1.62 pounds and includes a lanyard and USB Type C cable. The listing does not state driver size, frequency response, battery life, or finish material, which limits a full technical evaluation.

This review is based solely on the product listing and published data. No in-person testing was performed. The information below evaluates what the listing claims and what remains unknown, using general audio knowledge for context.

Sound Quality

On paper, the S620 promises 360 degree stereo sound and a cinematic surround effect. The 60 watt output suggests it can produce substantial volume for a portable speaker of this size. Two EQ modes allow switching between indoor mode for deep bass and outdoor mode for dynamic treble, giving users some tonal control without an app.

The listing does not provide a frequency response range or sensitivity figure, so the tonal accuracy cannot be assessed in detail. Buyers report that indoor mode delivers a fuller low end, while outdoor mode prioritizes clarity and projection. A single unit cannot reproduce true left and right stereo channels because the drivers are housed in one compact cylinder, so pairing a second S620 is required for genuine stereo separation.

Without driver information, the exact character of the midrange and treble remains uncertain. The 360 degree design suggests even sound dispersion around the speaker, but the actual off axis response is not documented. For casual listening at moderate volumes, the sound may be satisfying, but critical listeners will miss measurable frequency response and distortion figures.

Drivers, Power and Room Fit

The listing does not publish the driver size or number of drivers inside the S620. The key power figure is 60 watts of audio output, which is high for a budget portable speaker and should provide enough headroom for outdoor environments. This power rating suggests the speaker can fill small to medium rooms and serve small outdoor gatherings without straining.

With a second S620 in true wireless stereo mode, total output doubles to 120 watts, which may cover larger spaces or provide more even coverage in open areas. The cylindrical cabinet can be placed vertically or sideways, providing some placement flexibility. However, without a maximum sound pressure level or sensitivity rating, it is hard to compare output to reference models like the JBL Flip 6 or Bose SoundLink Flex.

The speaker is not designed as a room filling hi fi component for critical listening. Its strength is portability and outdoor projection rather than precise imaging. For a bedroom, kitchen, or patio, it should be adequate for background music or casual listening. Users who need concert level volume for large parties should consider multiple units or a larger speaker.

Features and Connectivity

Bluetooth 5.4 connectivity supports pairing with phones, tablets, and laptops, offering improved stability and lower latency compared to older Bluetooth versions. True wireless stereo pairing links two S620 units for left and right channel playback, a feature that is useful for wider soundstaging. A TF card slot allows offline music playback without a phone, which is handy when a device battery is low or a phone is not available.

The IPX8 waterproof rating means the speaker can withstand continuous immersion in water, though the listing does not specify depth or duration. The two EQ modes are simple presets selected by a button, with no companion app or custom tuning, so users cannot adjust bass or treble beyond the two options. A USB Type C charging cable is included, but no wall adapter is provided, so users will need their own power source for charging.

The built in microphone enables hands free calling, which works when the speaker is paired to a phone. This feature is useful for taking calls while cooking, working, or outdoors. However, the listing does not mention any voice assistant integration or multipoint Bluetooth, so only one device may be connected at a time.

• Bluetooth 5.4 with true wireless stereo pairing
• TF card slot for offline playback
• Hands free calling via built in microphone
• IPX8 waterproof rating for water exposure
• Two EQ modes: indoor and outdoor

Build, Design and Finish

The S620 measures 8.59 inches deep, 3.29 inches wide, and 3.29 inches high, weighing 1.62 pounds. The cylindrical shape is portable and can be placed upright or on its side, making it easy to tuck into a bag or cup holder. A braided lanyard is included for carrying or hanging the speaker, which adds practicality for outdoor activities.

The listing states the speaker is durable and robust, but does not identify the cabinet material or finish coating. The color is black, as noted in the listing title. IPX8 waterproofing suggests a sealed enclosure, which should protect internal components from moisture and allow use near water without immediate damage.

No drop resistance rating or specific material grade is published, so long term ruggedness is uncertain. The overall design appears simple and functional, prioritizing portability over premium materials. Buyers who handle the speaker roughly will appreciate the lanyard and waterproof build, but should still avoid unnecessary impacts.

Setup and Placement

Pairing the S620 over Bluetooth should be straightforward using the Bluetooth 5.4 protocol, and the listing does not mention NFC or multipoint pairing. For true wireless stereo, users must pair two S620 units, which typically requires pressing a pairing button on each speaker and following the quick start guide. The process is likely simple but the listing does not detail button sequences.

Placement is flexible because the speaker can stand vertically or lie horizontally. The lanyard allows hanging from a backpack, bicycle, tree branch, or shower head. The indoor and outdoor EQ modes can be toggled based on the environment, so users can quickly switch from a bass heavy home sound to a brighter outdoor projection.

Charging uses the included USB Type C cable, but the listing does not state charging time or battery capacity. Users should expect to charge before first use and may need to carry a power bank for extended trips. TF card playback may require formatting the card to FAT32, though the listing does not specify supported file systems or formats.

Daily Use

At 1.62 pounds, the S620 is easy to carry for daily errands, workouts, or travel. The lanyard makes it convenient to attach to a bag, belt, or bike, and the speaker can be hung near a shower or pool. The two EQ modes allow quick sound adjustments without reaching for a phone, which is helpful when moving between indoors and outdoors.

The built in microphone supports hands free calls, which is useful when the speaker is paired to a phone and the user is busy with tasks. TF card input provides an offline music option, helpful when a phone is not available or battery conservation matters. The speaker can be placed on a desk, table, or nightstand, and its cylindrical shape lets it fit in cup holders in some vehicles.

The lack of published battery life is a significant gap for daily use. Buyers may need to recharge frequently if they use high volume or outdoor mode, and there is no battery indicator mentioned in the listing. The listing does not mention a low battery warning, so users may be caught off guard when the speaker dies unexpectedly.

Who Should Buy It

Outdoor enthusiasts will find the S620 appealing because of its IPX8 waterproofing and lightweight design. Beach goers, pool users, and campers can use it without worrying about splashes or rain. The included lanyard makes it easy to carry on hikes, bike rides, or trips to the park.

Budget conscious buyers who want high output and TWS pairing will appreciate the 60 watt power and ability to link two speakers for stereo. Those who prefer offline playback via TF card will use it without a phone, which is useful for places with limited connectivity. The built in microphone adds convenience for calls during daily routines.

This speaker is not for audiophiles who need detailed driver specs or accurate frequency response. It is also not for users who require a published battery life for long trips or all day use. Home listeners seeking true stereo from one unit should look for a pair of bookshelf speakers instead.

Alternatives Worth Considering

The JBL Flip 6 is a well known portable waterproof speaker with a more established reputation and published specifications. It also offers Bluetooth and a durable build, though its output power is lower on paper than the S620. Buyers who prioritize brand reliability and detailed specs may prefer the Flip 6, but it typically costs more than the budget tier S620.

The Bose SoundLink Flex is another alternative with waterproofing and a rugged design. It is often praised for clear sound and a compact form factor, but it usually sits in a higher price bracket. For home use, the Edifier R1280DB powered bookshelf speakers provide a more detailed stereo image and better tonal balance, but they are not portable or waterproof, and they require AC power.

If TWS pairing and high wattage are priorities at a low price, the Monster S620 competes with many generic cylindrical speakers. The Monster brand name and design team may provide some confidence, but the missing specs remain a drawback. Buyers should compare based on published battery life and user reviews before deciding.

Verdict

The Monster S620 is a rugged budget portable speaker with strong on paper features: 60 watts, IPX8 waterproofing, Bluetooth 5.4, and true wireless stereo pairing. Its lightweight cylindrical build and included lanyard make it practical for outdoor adventures. The TF card slot and built in microphone add everyday flexibility for calls and offline music.

However, the listing omits critical audio details such as driver size, frequency response, and battery life. A single unit cannot produce true stereo despite marketing language that suggests 360 degree surround. With a score of 66 out of 100, the S620 is a reasonable choice for casual outdoor listeners who value waterproofing and power over measurement accuracy and detailed audio performance.

Strengths and Limitations

Alternatives to Consider

Tribit StormBox Micro 3

Best for cyclists, hikers and travelers who want a small waterproof speaker with a strong mount and all day battery life.

Read the Tribit StormBox Micro 3 review →

Logitech Z207

Budget-minded computer users who want a simple stereo speaker pair with both wired and wireless input for near-field listening.

Read the Logitech Z207 review →

Monster SD100

Budget desktop and gaming setups that want a compact powered speaker with Bluetooth, RGB lighting and occasional portable battery use.

Read the Monster SD100 review →

Questions Buyers Ask