There’s a reason the Logitech Z623 keeps showing up on desks, in lounge rooms and beside gaming rigs years after it first landed in Australia: it’s a THX-certified 2.1 system with a genuinely big subwoofer, and it simply refuses to die. That longevity is exactly why buying one used makes so much sense. The people selling them aren’t offloading broken gear — they’re upgrading, moving house, or finally going to a soundbar, and you get to inherit a set of speakers that was over-engineered from day one.
The numbers that change the conversation
Top used logitech z623s on eBay right now
Here’s what’s listed and selling in Australia today — complete sets, sub-only spares and bargain “as is” units all show up here.
Listings update automatically and open in a new tab.
Why second-hand is not “second best”
The Z623 is built around components that age gracefully. The subwoofer cabinet is a heavy MDF box with a down-firing driver — there’s nothing in it to “wear out” with normal use, and a five-year-old unit moves air exactly the way a new one does. The two satellites use simple cone drivers in solid plastic enclosures, and because the whole system is analogue (RCA and 3.5 mm inputs, no Bluetooth, no firmware, no app), there’s no software to go stale and no account to transfer. What you hear on day one of ownership is what the original buyer heard.
That matters because the Z623’s reputation rests on output that older powered speakers struggle to match: 200 watts RMS of total system power and THX certification, which is unusual at this price point even when new. A used set delivers the same chest-thump from films and games for a fraction of the outlay. The most common “fault” you’ll read about — a faint hum or a finicky volume pot — is almost always cosmetic noise rather than driver damage, and it’s easy to test for before you hand over a cent.
A Z623 that survived five years on someone’s desk has already proven the one thing a brand-new box can’t: that it lasts.
The savings are real
Across the used market in Australia, a complete Z623 set — subwoofer, both satellites and the control cable — routinely changes hands for a meaningful slice off the retail figure, landing well inside that 20-60% saving band. The exact number swings with condition, whether the original RCA and power leads are included, and how close the seller is to you (these are heavy, and a subwoofer is no fun to post). Buy local, collect in person, and you keep the discount instead of feeding it to a courier.
New vs used, side by side
| Brand new | Used / refurbished | |
|---|---|---|
| Price | Full retail | Typically 20-60% less |
| Sound output | 200W RMS, THX certified | Identical — analogue drivers don’t degrade |
| Included cables | All in the box | Confirm RCA + power lead are present |
| Warranty | Full manufacturer cover | ACL still applies via a business seller |
| Environmental cost | New manufacturing CO2 | Re-uses gear already made |
| Availability | Stock-dependent | Strong second-hand supply |
The five-minute checklist before you pay
- Both satellites and the sub present. The Z623 is a 2.1 set — a subwoofer with only one satellite is half a system and worth far less.
- The control cable. The right satellite carries the volume knob, power switch and inputs, and connects to the sub with a captive multi-pin lead. Make sure it’s intact — it’s not a standard cable you can swap.
- Power up and listen. Run something with real bass. The sub should be tight and punchy, not buzzing, rattling or distorting at moderate volume.
- Work the volume knob fully. Turn it through its whole range; crackle or dropouts point to a worn potentiometer, the system’s one common ageing point.
- Check both inputs. Test the RCA and the 3.5 mm headphone-style input so you know both work for whatever you’ll plug in.
- Inspect the satellite cones. Look for pushed-in or torn cones — curious fingers and pets are the usual culprits.
You have more protection than you think
Buying from a business — an electronics reseller, a refurbisher, or a registered eBay store — means the Australian Consumer Law travels with the purchase. Goods must be of acceptable quality and do what you’d reasonably expect, and that guarantee can’t be waived with a “sold as is” sticker when the seller is in trade. If a used Z623 arrives with a dead amplifier or a sub that won’t power on, you have a clear right to a repair, replacement or refund. Private sales carry fewer guarantees, so favour a business seller when the saving is similar.
Ready to find yours?
Browse current used and refurbished Logitech Z623 deals from trusted Australian sellers below.
Red flags to walk away from
- “Subwoofer only” dressed up as a full system. Without both satellites and the control lead, you can’t actually run it.
- No power-on photo or video. For a powered speaker, a seller who won’t show it lit up and playing is hiding something.
- Constant hum described as “normal”. A loud mains buzz that’s present even with nothing plugged in can mean a failing internal supply.
- Missing or substituted power brick. The amplifier lives in the sub and draws real current; a random replacement adaptor is a fire and failure risk.
- Cracked sub cabinet. A split MDF box leaks air and kills the bass the Z623 is famous for.
Frequently asked questions
Does the Z623 work with a TV? Yes — if your TV has an analogue RCA or 3.5 mm audio output, or a headphone jack, it plugs straight in. There’s no HDMI or optical input, so check your TV’s outputs first.
Can I use it with a PC, console and phone at once? It has two inputs (RCA plus a 3.5 mm), so you can keep two sources connected. A cheap aux splitter or switch covers more devices.
Is there Bluetooth? No. The Z623 is purely wired, which is part of why used units stay reliable — nothing to pair, update or break. Add a small Bluetooth receiver to the aux input if you want wireless.
Are the satellites and sub matched, or can I mix units? They’re tuned as a set. Buy a complete system rather than trying to pair a sub from one with satellites from another.
The bottom line
The Logitech Z623 is one of those rare pieces of audio gear that’s a genuinely smart used buy: simple analogue engineering, a serious subwoofer, THX certification, and almost nothing inside to wear out. Test the volume knob, confirm both satellites and the control cable are there, hear the bass for yourself, and lean towards a business seller so the Australian Consumer Law has your back. Do that, and you’ll land a system that out-punches most new desktop speakers for a fraction of the price — while keeping a perfectly good set of speakers out of the e-waste stream.
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