Roku Streambar SE vs Fire TV Cube: Soundbar-Streamer or Alexa Hybrid?

Choosing between the Roku Streambar SE and the Amazon Fire TV Cube (3rd Gen) is the living-room fork for people who want more than a slim HDMI stick: a compact soundbar with Roku built in versus Amazon's fabric cube that pairs far-field Alexa with a full Fire TV box. Specs and street prices below come from maker sheets and current Amazon US listings, not a lab shootout.

This head-to-head is not a stick-class duel. For under-$50 sticks, start with Best Streaming Sticks Under $50 (2026) and the narrower Fire TV Stick 4K vs Chromecast with Google TV. Premium boxes that win on Continuity or Plex muscle still live on Apple TV 4K vs NVIDIA Shield TV Pro. Neither Streambar SE nor Cube replaces those lanes.

Quick verdict

Most living-room upgrades that need better dialogue and simpler cable clutter should buy the Roku Streambar SE. It sits under the TV, runs Roku's free-and-live heavy UI, and advertises Enhanced Speech Clarity plus Bluetooth headphone pairing in one HDMI/optical path. Buy the Fire TV Cube when the house already runs on Alexa, you want hands-free control across the room, or you need HDMI-in to switch a cable box / console by voice — and you are fine buying a separate soundbar or AVR for real volume.

Form factor and placement

Winner: Streambar SE for under-TV clutter; Cube for a visible smart-speaker shelf spot. Streambar SE is a short black soundbar meant to sit centered under the panel (or on a shelf in front of the stand). One device replaces "stick behind the TV + cheap bar" for small rooms and apartments. Fire TV Cube is a fabric-wrapped cube with a mic array and weak built-in speaker: it wants to live in view on a console so Alexa can hear you, not hide behind the panel. If invisibility matters, Streambar wins. If you already leave Echo speakers out, Cube fits the furniture language.

Built-in audio vs Alexa speaker

Winner: Streambar SE for TV dialogue and music-from-the-bar; Cube only for Alexa voice replies. Streambar SE is sold as a 2-in-1: Roku streaming plus premium compact speakers with Enhanced Speech Clarity, auto volume leveling, and Bluetooth for wireless headphones or phone music. It is still a small bar — not a 5.1 kit — but it is explicitly the audio upgrade path. Cube's onboard speaker is for Alexa talkback; Amazon's own positioning expects a separate soundbar, AVR, or Echo for room-filling sound. Buy Streambar when "TV audio is tinny" is why you opened this page. Buy Cube when voice-first Fire TV is why, and budget a real sound system beside it.

Streaming UI and apps

Winner: Streambar SE for Roku's free/live depth and customizable home; Cube for Prime Video / Alexa search depth. Both carry the major US streamers (Netflix, Disney+, Max, YouTube, Hulu, Prime Video). Roku leans hard on free and live rows plus a home you can pin. Fire TV leans on Amazon's catalog, Freevee-style rows, and Alexa-powered search (including newer AI-powered Fire TV Search claims on the current Cube listing). Privacy-minded buyers who dislike storefront noise often prefer Roku; Amazon-household buyers who live in Prime Video will not mind Fire's home row. Neither UI is a blank desktop.

Axis	Roku Streambar SE	Fire TV Cube (3rd Gen)
Street price band	~$89 to $99	~$140 to $200
Form	Compact under-TV soundbar	Fabric cube on shelf
Built-in audio role	TV speakers / dialogue upgrade	Alexa talkback only
Streaming OS	Roku OS	Fire OS
Voice	Roku Voice Remote (+ works with Alexa/Google devices)	Far-field Alexa + Alexa Voice Remote
Ports / net	HDMI, Optical, Wi-Fi, Bluetooth	HDMI in + out (ARC), Ethernet, USB-A, Wi-Fi 6E
HDR / audio claims	4K HDR / HDR10+ streaming	4K with Dolby Vision, HDR, Dolby Atmos path
Best fit	One-box sound + stream	Alexa homes + HDMI-in switching

HDMI ARC, remotes, and TV control

Winner: Cube for HDMI-in source switching and far-field Alexa; Streambar SE for simple bar + remote TV control. Streambar SE connects over HDMI or optical and ships with a Roku voice remote that learns TV power and volume on compatible sets — classic one-remote living-room setup. Cube adds an HDMI input so a cable box, game console, or webcam can pass through and switch by voice, plus HDMI output with ARC, Ethernet, USB-A, and IR extender support on the 3rd-gen hardware. That HDMI-in path is unique versus stick-class and versus Streambar. Pick Cube when "Alexa, switch to the cable box" is a real daily phrase. Pick Streambar when you just want the bar and the Roku remote to run the TV.

Voice assistants and smart-home fit

Winner: Cube for Alexa-first homes; Streambar SE when Roku remote is enough (and optional Alexa/Google device control of Roku). Cube is built around a four-mic far-field array: wake Alexa across the room with the TV off, mute with a hardware button, and drive compatible TVs, soundbars, and receivers by voice. Streambar SE's daily driver is the Roku Voice Remote; Roku also documents control from Alexa- and Google Assistant-enabled devices for launch/search/playback on many setups, but that is accessory assistant depth — not a built-in Echo. Match the assistant your lights and speakers already use. Do not buy Cube hoping for a Roku-first home screen, and do not buy Streambar hoping for Echo-class far-field mics in the bar.

Dolby, Atmos, and picture claims

Winner: Cube on Dolby Vision / Atmos marketing; Streambar SE on practical HDR10+ streaming plus clearer spoken dialogue. Current Cube listings advertise true-to-life 4K with Dolby Vision, HDR, and Dolby Atmos audio paths when the TV and sound system cooperate. Streambar SE is positioned for 4K HDR / HDR10+ streaming with speech-clarity features aimed at dialogue, not a full Atmos cinema claim on the bar itself. If Dolby Vision titles and Atmos passthrough into a separate AVR are the buy reason, Cube (plus speakers) wins the format checklist. If dialogue clarity from the device under the TV is the buy reason, Streambar wins the lived-in axis.

Setup friction and expandability

Winner: Streambar SE for guided one-box setup; Cube when ports and Alexa routines are worth the extra furniture. Streambar SE markets quick guided setup: power, HDMI or optical, Wi-Fi, remote pairing. Optional Roku wireless bass and surrounds exist in the broader Roku audio family if you expand later. Cube setup is still guided, but you are placing a always-listening cube, linking Amazon accounts, and often wiring HDMI-in plus a separate sound path. Cube then wins on expandability: Ethernet, USB storage, Wi-Fi 6E, HDMI-in matrix-style switching. Streambar wins on "open box, under TV, done."

Who should buy which

Buy Roku Streambar SE if:

• TV speakers are thin and you want one slim bar that also streams
• You prefer Roku's free/live home and a simple voice remote
• Budget wants to stay near the under-$100 street band
• You do not need far-field Alexa or HDMI-in switching

Buy Fire TV Cube if:

• The household already uses Echo speakers, Alexa routines, and Prime Video daily
• You want hands-free Alexa across the room and HDMI-in for a cable box or console
• Wi-Fi 6E, Ethernet, and USB matter more than built-in bar speakers
• You will pair a real soundbar or AVR for volume (Cube's speaker is not the audio upgrade)

Skip both and pick a stick if:

• The TV already has good speakers or a soundbar you like, and you only need apps under ~$50 — see Best Streaming Sticks Under $50 (2026) and Fire TV Stick 4K vs Chromecast with Google TV

Skip both and step up if:

• Continuity / HomeKit or serious Plex local-media muscle is the real goal — see Apple TV 4K vs NVIDIA Shield TV Pro

Bottom line

For a living-room TV upgrade that is bigger than a stick, take the Roku Streambar SE when dialogue, under-TV clutter, and a Roku home screen are why you are shopping. Take the Amazon Fire TV Cube (3rd Gen) when far-field Alexa, HDMI-in switching, and Fire OS depth win — and plan separate speakers for real sound. Specs here are from maker sheets and Amazon listings, not a lab day. Confirm current street pricing, then View on Amazon before you order.