Saramonic K9 XTX Released – Plug-On UHF Transmitter With 32-Bit Float Recording, Timecode, and 48V Phantom Power

Audio News

by Johnnie BehiriAugust 6^th, 2026

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Saramonic has released the K9 XTX, a digital UHF plug-on transmitter that turns any wired XLR microphone into a wireless one. It covers 550 to 960 MHz with GPS-based regional frequency updates, offers selectable 3V to 48V phantom power, records 32-bit float WAV files onboard, generates and reads LTC timecode, and runs on two AA batteries, with prices starting at $299.

Plug-on transmitters occupy a specific, unglamorous corner of the location sound world: they exist so that a boom operator can lose the cable, or so a reporter can hand a wired handheld microphone to someone standing 100 meters from the recordist. Historically, that convenience came with a compromise, since most plug-ons relied on analog companding that audibly altered the sound of the microphone attached to them. The K9 XTX is Saramonic’s attempt to remove that compromise by putting its digital UHF platform, the one we first saw in the K9 audio system at NAB 2025, into a body that screws onto the back of an XLR microphone. The K9 system also took home a CineD Best-of-Show Award at NAB 2025, so the underlying platform is one we already have some history with.

Wideband UHF rather than 2.4 GHz

The K9 XTX transmits across a 550 to 960 MHz range using Saramonic’s proprietary digital RF modulation, with a 100 kHz tuning step, 200 kHz RF bandwidth, and 700 kHz channel spacing. Selectable RF output runs at 10, 25, 50, or 100 mW, and the antenna attaches via a 50 Ω SMA connector, which means the transmitter can in principle be paired with different antenna lengths for different frequency blocks rather than being locked to one whip.

Saramonic quotes stable transmission of up to 150m (492ft) at 50 mW under favorable conditions, a figure that should be treated the way all manufacturer range claims are treated, as a best case in open air rather than a promise for a concrete stairwell. The more meaningful argument for UHF is not raw distance but company: on a set already saturated with 2.4 GHz video transmitters, camera control links, and phones, sitting in the UHF spectrum keeps audio out of the busiest neighborhood.

Because UHF allocations differ by country, the K9 XTX uses a GPS-based frequency system that adapts the available frequencies to local regulations. Saramonic still sells the K9 range in region-specific frequency variants, so buyers moving between territories should confirm which block they are ordering before committing.

Phantom power for anything with an XLR on it

The input side is where a plug-on either fits your kit or does not. The K9 XTX uses a locking 3-pin XLR connector and offers phantom power at 3V, 5V, 12V, 24V, and 48V, plus a line-level setting for feeding it from a mixer or recorder output. That range covers full 48V condensers such as a boom-mounted shotgun, lower-voltage designs, dynamic handhelds that need no power at all, and line sources.

Gain is adjustable from 0 to 30 dB, with a switchable low cut at 75, 100, or 150 Hz. Frequency response is quoted at 20 Hz to 20 kHz with distortion below 0.5%, and equivalent input noise at maximum gain is rated at -132 dBV (-130 dBu) A-weighted with a 150 ohm source, which is a competitive figure for a device this size. Saramonic claims 130 dB of input dynamic range, the same headline number attached to the wider K9 system, and argues that this is what allows a professional microphone to keep its character rather than being squeezed through a compander. Transmission itself is 24-bit at 48 kHz.

For productions using 5-pin stereo broadcast microphones, Saramonic points to a standard 5-pin to dual 3-pin splitter cable as the workaround; there is no 5-pin version of the transmitter.

Onboard 32-bit float recording as a safety net

The K9 XTX records internally to WAV at 48 kHz, in either 24-bit or 32-bit float, onto a microSD card. Saramonic ships a 64 GB card in the box and the slot accepts cards up to 256 GB. Recording onboard while transmitting is the whole point of the feature: the wireless feed goes to the recordist or the camera, and an unclipped, unmissable copy of the same audio stays on the microphone itself.

One important caveat carries over from the original K9 system. When that system launched, Saramonic explained that patent restrictions in the US prevent simultaneous wireless transmission and internal recording on units sold and operated there, while the two functions can be used independently, and that the GPS-aware app enables both simultaneously outside the US. Saramonic has not addressed whether the same limitation applies to the K9 XTX, so US buyers who want a transmitting backup recorder should confirm that point with the company or their dealer before ordering. It is exactly the kind of detail that only matters once, on the day it ruins a take.

Timecode without a separate box

The K9 XTX reads and generates LTC (SMPTE) timecode at 23.98, 24, 25, 29.97, 29.97 drop frame, and 30 fps, with a quoted clock accuracy of 0.15 ppm, which Saramonic translates to less than one frame of drift across 48 hours. Sync can come wirelessly through the Saramonic System app, over a cable from a third-party master clock, or from the company’s own TC-NEO timecode generator.

Having timecode stamped into the transmitter’s own recordings, rather than in a separate recorder further down the chain, is what makes the backup file genuinely useful. A 32-bit float WAV with matching timecode drops into DaVinci Resolve or Premiere Pro and lines up without anyone hunting for a clap, which is the difference between a safety recording and a chore.

The same app handles remote control of up to 48 devices, covering grouping, sleep modes to preserve battery, and firmware updates. For a sound team running several transmitters across a location, not having to physically reach a unit clamped to the end of a boom pole is a practical gain rather than a marketing bullet.

Power, build, and the numbers that matter on a pole

The transmitter measures 80 x 62 x 19mm / 3.15 x 2.44 x 0.75in and weighs 220g / 7.8oz without batteries and antenna, or 252g / 8.9oz fully loaded. That is mass hanging off the back of a microphone on the end of an extended boom, and boom operators will feel it, though it is in line with other plug-ons carrying this much functionality.

Power comes from two replaceable AA batteries, and here Saramonic’s own figures diverge: the product page quotes 7+ hours of operation from two AA cells, while the company’s store listing and marketing material cite up to 14 hours, with a lithium battery pack included in the box. We would treat the lower number as the safe planning figure until the discrepancy is clarified. USB-C provides external power and charging, so a power bank can carry the unit through a long day either way.

Operationally, the K9 XTX has a color screen with menu navigation rather than a two-line LCD, a locking XLR mount to stop the transmitter working loose, and an operating range of -30°C to 60°C / -22°F to 140°F. Sweat and light moisture resistance is built in, and Saramonic quotes an IP66 rating only when the unit is used with an optional waterproof case, which is sold separately.

Where it sits in Saramonic’s lineup

The K9 XTX is not a standalone system; it is a transmitter for the K9 ecosystem, which is why the kit configuration bundles it with a K9 transmitter and receiver. Anyone already running K9 gear gains an XLR input for an existing setup, while newcomers can join the platform with a single purchase. It also fills an obvious gap above Saramonic’s creator-facing products such as the Saramonic Air and alongside the professional intercom side of the business, most recently the WiTalk9 X.

The competitive question is whether a $299 digital plug-on with onboard 32-bit float and timecode pressures the established names in this category, where comparable units from the traditional wireless manufacturers typically cost several times more and often lack internal recording entirely. Specifications on a page are not the same as RF performance in a crowded venue, so this is a product we would want to hear before concluding.

The Saramonic K9 XTX is available now, priced at $299 for the transmitter on its own, which includes the 64 GB microSD card, an SMA elbow antenna, XLR and USB-C cables, a lithium battery pack, and a carrying bag. The K9 XTX Kit, which adds a K9 bodypack transmitter, a K9 receiver, a lavalier microphone, a cold shoe mount, a belt clip, and further cabling, costs $749. Both are listed on the Saramonic online store, with full specifications on the official K9 XTX product page. The waterproof case is a separate purchase.

Would a digital plug-on with onboard 32-bit float and timecode change how you rig your boom or handheld work? Don’t hesitate to let us know in the comments below!