Word Clock

Antelope Audio OCX HD Master Clock

The Antelope Audio OCX HD is the current standard-bearer master clock: oven-controlled oscillator stability, eight word clock 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.

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Photos

Manufacturer product photography — the drawn faceplate stays true to panel layout; these show the hardware itself.

Antelope Audio OCX HD Master Clock — Photo: Antelope Audio1 / 2

Documented outputs: 33 destination connections
Documented inputs: 2Based on documented inputs
Rack space: 1UBuilder checks available rail space
Power draw: 15W20W documented maximum
Catalog estimate: ~$1,690Use retailer rows for current price and stock

01 · What it does—and what that changes in your rig.

Product overview

Start with the payoff, then work through how it functions, where it fits, and the details that change a real build.

The payoff

Word Clock decisions, organized around the whole rig.

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 converters, a digital console, and a stage box all sharing a word clock, 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 IEM 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.

Documented outputs: 33 destination connections
Documented inputs: 2Based on documented inputs
Rack space: 1UBuilder checks available rail space

Antelope Audio OCX HD Master Clock — rear panel — Photo: Antelope Audio1U · 15W

Function

How it works in the path

Eight BNC word clock outputs means you can feed a console, a redundant playback system, an interface, and several converters simultaneously without daisy-chaining — which is the right way to do it. Daisy-chaining distributes jitter down the chain; star-wiring from a single reference keeps each device on the same footing. The AES and S/PDIF 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 1U shallow 220mm depth, it fits cleanly in most rack builds without a fight.

Best fit

Where it earns its place in the rack

If you're running three or more digital devices that need a common clock reference — especially on a show where drop-outs 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 ADAT and you're happy letting one device clock the other. In that scenario, the internal clock on a quality converter 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

Details worth deciding before load-in.

Star-wire all eight BNC outputs individually to each device — never loop word clock 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 BNC 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 conditioner or dense patchbay shortens component life.

02 · Know the whole path before you buy.

Signal path

Learn the route as a block diagram: source, product function, transport, and destination. Select any block to see what enters, what changes, and what leaves.

Interactive block diagramAuto-looping · hover, focus, or tap to hold a stage

Port-type signalProduct functionSystem boundary

Follow one signal from source to destination

Each block answers the same three questions: what arrives, what changes here, and what leaves.

01 · Source · selected

01 · Source

2 documented inputs

bnc + IEC C14

Arrives as: 2 documented inputs
Connector: bnc + IEC C14
Signal: digital audio

03 · What this product asks of the rest of the system.

Compatibility

Treat connector names as the start of the check—not the answer. These are the boundaries that determine a complete working path.

Best fit · Word Clock

Use it when 1U and 220 mm of depth fit the case.

Plan the companion path

Complete the path with upstream and downstream gear that matches connector, direction, signal type, protocol, and wiring standard.

Connector boundary

Documented connectors: bnc, aes3 xlr, spdif coax, IEC C14. Match connector, direction, and signal type—not shape alone.

04 · Every connector, grouped by job.

I/O ports

Switch the product view and the documented port inventory updates with it—hardware and data stay side by side.

Every connector, grouped by job.

Switch panels to keep the hardware view and the documented port list in sync.

Panel view

Front panel

Rear panel

All documented ports for Antelope Audio OCX HD Master Clock
Port	Panel	Connector	Direction	Signal	Channels
Word Clock Out 1-8	rear	bnc	output	digital audio	8
AES Out	rear	aes3 xlr	output	digital audio	—
S/PDIF Out	rear	spdif coax	output	digital audio	—
10M Atomic In	rear	bnc	input	digital audio	—
Power	rear	IEC C14	input	power	—

Showing 5 of 5 documented physical ports.

05 · Compare the decision, not just the price.

Alternatives

The rows are organized around fit, power, I/O, and system role so a cheaper unit cannot hide a more expensive workflow.

Compare	Antelope Audio OCX HD Master ClockThis gear	Antelope Audio Trinity Master Clock
Fit	📐 1U	📐 1U
Power	⚡ 15W	⚡ 20W
Weight	⚖️ 5.5 lb	⚖️ 5.5 lb
I/O	🔌 5	🔌 6
Estimate	💵 ~$1,690	💵 ~$3,495
Deep dive	Current selection	Full comparison →

06 · Resolve the questions that can change the purchase or build plan.

Planning questions

Short, source-backed answers surface rack fit, power, cabling, and connection details before they become surprises.

How will the Antelope Audio OCX HD Master Clock affect rack fit and case depth?

It occupies 1U. Its documented depth is 220 mm.

How much power does the Antelope Audio OCX HD Master Clock draw?

Typical draw is 15W and documented maximum draw is 20W.

What connections does the Antelope Audio OCX HD Master Clock have?

5 documented physical ports, including Word Clock Out 1-8, AES Out, S/PDIF Out, 10M Atomic In, Power.

07 · See this unit inside a real rack plan.

Builder preview

Placement is only the start. Builder checks space · depth · weight, power headroom, dependencies, and compatible signal paths around this exact catalog item.Open in Builder

08 · Related gear, in the order you may need it.

Word Clock

Antelope Audio Trinity Master Clock

1U · 6 ports · ~$3,495

Planning guides for word clock systems.

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