Definitive Technology Mythos 3C-85 vs KEF XIO Silver Grey
Prices updated hourly. Check retailer for current availability.
Choosing between the Definitive Technology Mythos 3C-85 and KEF XIO Silver Grey? Both compete in the Soundbar segment. Here’s how they compare across the specs that matter most for your home theater.
Pricing for both models is currently unavailable. Check the retailer links below for current deals.
Looking at overall performance dimensions: The Definitive Technology Mythos 3C-85 scores higher in value. The KEF XIO Silver Grey leads in form factor, room fit. They score similarly in ease of use.
These soundbars differ in channel configurations of 3.0 vs 5.1.2, and only the KEF XIO Silver Grey includes Dolby Atmos support. Atmos adds a height dimension to surround sound, placing sounds above you. It's object-based, so the receiver decides which speakers reproduce each sound based on your layout.
These two Soundbar options trade wins across different dimensions. The right choice depends on which specs matter most for your room and listening preferences — review the detailed table below to decide.
For most home theaters, the KEF XIO Silver Grey is the stronger choice — it leads in 2 of 4 scored dimensions. The Definitive Technology Mythos 3C-85 makes more sense if you prioritize the 1 dimension where it leads.
Performance Overview
Scores based on specs and category benchmarks (0–100 scale)
Definitive Technology Mythos 3C-85
KEF XIO Silver Grey
Detailed Specifications
| Specification | ||
|---|---|---|
| Price | N/A | N/A |
| Channel Config | 3.0 | 5.1.2 |
| Total Power (RMS) | — | 820W |
| Driver Count | 13 | 12 |
| Freq Response Low | 100Hz | — |
| Freq Response High | 25000Hz | — |
| Passive | Yes | No |
| Dolby Atmos | No | Yes |
| Dolby Digital+ | No | Yes |
| Dolby TrueHD | No | Yes |
| DTS:X | No | Yes |
| DTS Virtual:X | No | No |
| DTS-HD Master | No | No |
| Built-in Sub | No | No |
| Wireless Sub Included | No | No |
| Wireless Sub Support | No | Yes |
| Wireless Surround Support | No | Yes |
| HDMI eARC | No | Yes |
| HDMI Inputs | 0 | 1 |
| HDMI Version | — | 2.1 |
| Optical Input | No | Yes |
| Analog Stereo In | No | No |
| Sub Pre-Out | No | Yes |
| Ethernet | No | Yes |
| Bluetooth | No | Yes |
| BT Version | — | 5.3 |
| Wi-Fi | No | Yes |
| Wi-Fi Standard | — | Wi-Fi 6 |
| AirPlay 2 | No | Yes |
| Chromecast | No | Yes |
| Spotify Connect | No | Yes |
| Voice Assistants | ||
| Room Calibration | — | KEF Connect |
| Dialog Enhancement | No | Yes |
| Night Mode | No | Yes |
| App Control | — | KEF Connect |
| Wall Mountable | Yes | Yes |
Key Differences
- Channel Config: Definitive Technology Mythos 3C-85 at 3.0 vs KEF XIO Silver Grey at 5.1.2
- Driver Count: Definitive Technology Mythos 3C-85 at 13 vs KEF XIO Silver Grey at 12
- Total Power (RMS): Definitive Technology Mythos 3C-85 at — vs KEF XIO Silver Grey at 820W
- Freq Response Low: Definitive Technology Mythos 3C-85 at 100Hz vs KEF XIO Silver Grey at —. Determines how much bass a speaker handles on its own versus relying on a subwoofer for low-end support.
- Freq Response High: Definitive Technology Mythos 3C-85 at 25000Hz vs KEF XIO Silver Grey at —
See Where These Rank
Check our editorial rankings to see how Definitive Technology Mythos 3C-85 and KEF XIO Silver Grey compare to the rest of the field.
Best Soundbar RankingsSpecifications sourced from manufacturer datasheets and verified against retailer listings. Prices updated hourly from authorized retailers. Scoring uses our open methodology — products are never ranked, promoted, or suppressed based on affiliate commission rates.
Related Comparisons
CinemaConfig may receive compensation for purchases made at participating retailers linked on this site. This compensation does not affect what products or prices are displayed, or the order of prices listed. See our affiliate disclosure.