Antelope Audio OCX HD Master Clock
Antelope Audio·Model OCX HD·antelope-ocx-hd
Photos
Manufacturer product photography — the drawn faceplate above stays true to panel layout; these show the hardware itself.
About the Antelope Audio OCX HD
The Antelope Audio OCX HD is the current standard-bearer master clock: oven-controlled oscillator stability, eight word clockThe shared heartbeat keeping every digital box sampling in lockstep. One device leads, the rest follow — or you get clicks and pops. outputs, and rates to 768kHz. Studios and broadcast rigs hang whole digital ecosystems off it where clocking integrity is the difference between clean and brittle. Succeeds the discontinued Trinity in the Antelope line.
The OCX HD is a dedicated master clock — its entire job is to be the timing authority for every digital device in your rig. When you have multiple convertersThe circuitry that turns analog audio into digital data and back (A/D and D/A). Converter quality sets a digital rig’s sound ceiling., a digital console, and a stage boxThe I/O endpoint on stage: mics plug in there and one digital line (AES50, Dante) carries everything to the console. The snake, digitized. all sharing a word clockThe shared heartbeat keeping every digital box sampling in lockstep. One device leads, the rest follow — or you get clicks and pops., the question isn't whether clocking matters but who's doing it. Antelope's answer is an oven-controlled crystal oscillator, which keeps the internal reference thermally stable rather than drifting with ambient temperature. In a touring IEMIn-Ear Monitor — earpieces that replace floor wedges, feeding each player their own mix. The reason this whole rack exists. rig or a broadcast truck where the gear cold-soaks in a trailer overnight and warms up fast, that thermal stability is exactly the kind of problem a standard oscillator ignores.
Eight BNCThe twist-lock coax connector used for word clock and antenna runs — it locks, so it can’t be pulled out mid-show. word clockThe shared heartbeat keeping every digital box sampling in lockstep. One device leads, the rest follow — or you get clicks and pops. outputs means you can feed a console, a redundantA second copy of anything critical — supply, computer, network path — already running so one failure can’t stop the show. playback system, an interface, and several convertersThe circuitry that turns analog audio into digital data and back (A/D and D/A). Converter quality sets a digital rig’s sound ceiling. simultaneously without daisy-chaining — which is the right way to do it. Daisy-chaining distributes jitterTiny timing wobble in a digital clock. Enough of it smears detail and stereo image — why serious rigs care about clocking. down the chain; star-wiring from a single reference keeps each device on the same footing. The AES and S/PDIFConsumer-grade stereo digital audio on an RCA or optical connector — same idea as AES3 but unbalanced and shorter-range. outputs add flexibility for devices that don't take word clock directly. Support for rates up to 768kHz is largely academic for live work, but it means the unit is not a bottleneck if your session runs at 96kHz and you want to clock everything at session rate rather than converting down. At 15 watts steady draw in a 1UThe standard slice of rack height: 1U = 1.75″. A 3U box takes three slices; half-rack gear pairs two units side by side in one. shallow 220mm depth, it fits cleanly in most rack builds without a fight.
If you're running three or more digital devices that need a common clock reference — especially on a show where drop-outsA brief audio gap when the radio link fails — the thing diversity, distros, and coordination all exist to prevent. or digital noise are unacceptable — the OCX HD earns its place and its price. A $1,690 clock is hard to justify if your rig is a single interface feeding a console via ADATOptical digital audio: 8 channels at 48 kHz down one Toslink lightpipe (4 at 96 kHz). The usual way to add more channels to an interface. and you're happy letting one device clock the other. In that scenario, the internal clock on a quality converterThe circuitry that turns analog audio into digital data and back (A/D and D/A). Converter quality sets a digital rig’s sound ceiling. or console is good enough. This unit is for the engineer who has hit the ceiling of internal clocking and needs a reliable hub, or who is building a rig sophisticated enough that clock discipline is part of the design from day one.
In the rack
- Star-wire all eight BNCThe twist-lock coax connector used for word clock and antenna runs — it locks, so it can’t be pulled out mid-show. outputs individually to each device — never loop word clockThe shared heartbeat keeping every digital box sampling in lockstep. One device leads, the rest follow — or you get clicks and pops. out of one device into the next. The whole point of having eight outputs is avoiding that chain.
- Power the OCX HD first in your startup sequence and last off at shutdown. Every downstream device should lock to it, not scramble to find a reference while it's still booting.
- If your venue or truck has access to a 10MHz atomic or GPS reference, the BNCThe twist-lock coax connector used for word clock and antenna runs — it locks, so it can’t be pulled out mid-show. 10M input on the rear lets you lock the OCX HD to that source — one step tighter than the internal oscillator alone, and worth using in broadcast situations.
- Rack it with at least a half-unit of ventilation clearance above or below; 15 watts from an oven-controlled oscillator means the unit runs warm by design, and trapping that heat against a power conditionerFilters venue AC, clamps surges, and gives the rack one tidy inlet. Not a voltage regulator and not a battery — just cleaner power. or dense patchbayA panel of front-facing jacks wired to everything behind it — re-route any signal with a short cable instead of climbing behind the rack. shortens component life.
Current Antelope master clock — 768kHz, 8 word clockThe shared heartbeat keeping every digital box sampling in lockstep. One device leads, the rest follow — or you get clicks and pops. outs.
I/O Ports (5)
| Port | Connector | Direction | Signal | Channels |
|---|---|---|---|---|
| Word Clock Out 1-8 | BNC | output | digital audio | 8 |
| AES Out | AES3 XLR | output | digital audio | — |
| S/PDIF Out | SPDIF COAX | output | digital audio | — |
| 10M Atomic In | BNC | input | digital audio | — |
- Power (IEC C14)
Deciding between two?
Rack space, watts, weight and every connector, side by side.
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