Harman Kardon Onyx Studio 3 vs 4: What Actually Changed (2026)
Honest headline first: these are older, now-discontinued speakers, and the gap between them is smaller than the model number suggests — battery is the only real change.
If you’re choosing between the Harman Kardon Onyx Studio 3 and Studio 4, here’s the honest headline first: these are older, now-discontinued speakers, and the changes between them are smaller than the model jump suggests. Both use the same drivers and put out the same 60W, so they sound nearly identical — even longtime owners confirm it [HK; Amazon review]. What genuinely changed gen-to-gen is battery life (HK rates the Studio 3 up to 5 hours vs up to 8 on the Studio 4), Bluetooth (4.1 → 4.2), multi-speaker pairing (the 3’s two-speaker Wireless Dual Sound vs the 4’s 100+-speaker HK Connect+), and added Siri/Google voice on the 4 [HK]. New stock is largely gone, so most listings are used or renewed. We cover both honestly, then point you to a current model worth buying instead.
They sound effectively identical — same transducers, same 60W [HK] — so this comes down to battery and availability, not sound. Both are discontinued, so either way you’re buying a years-old battery used or renewed.
Want a warranty, a fresh battery and modern Bluetooth? Skip both and buy a current model — see the Onyx Studio 8 alternative below.
Onyx Studio 3 vs 4, head-to-head
Every figure is from Harman Kardon’s spec pages or a named review, cited inline. The “winner” calls are judgments based on those specs — not an in-house test.
| Dimension | Onyx Studio 3 | Onyx Studio 4 | Winner |
|---|---|---|---|
| Sound | 60W; 2×75mm woofers + 2×20mm tweeters; 50Hz–20kHz [HK] | 60W; identical drivers; 50Hz–20kHz [HK] | Tie (effectively identical per HK + owners) [HK; Amazon review] |
| Battery | 2600mAh, up to 5h [HK] | 3000mAh, up to 8h [HK] | Studio 4 |
| Design / weight | 2071g, narrower footprint [HK] | 2061g, wider footprint [HK] | Tie (near-identical) |
| Bluetooth | BT 4.1, up to 3 devices [HK] | BT 4.2, up to 2 devices [HK] | Mixed (4.2 newer; the 3 pairs more devices) |
| Durability | Steel / fabric, no IP rating [HK] | Steel / fabric, no IP rating [HK] | Tie (neither water-resistant) |
| Multi-speaker | Wireless Dual Sound — pairs exactly 2 [HK] | HK Connect+ — links 100+ [HK] | Studio 4 |
| Value | Cheapest way into the Onyx sound (used) | More battery + voice features (used) | Studio 4 |
- Sound is a genuine tie: HK lists the same transducers and the same 60W for both, and owners who’ve used each report they sound essentially the same — don’t pay extra expecting a sound upgrade [HK; Amazon review].
- Battery claims are best-case: HK’s “up to” hours are at moderate volume. Independent and owner reports put real-world life lower — roughly ~3h on the Studio 3 at high volume [AudioReputation] and ~4h on the Studio 4 [Amazon reviews].
- Both are discontinued: whichever you pick, you’re buying a years-old lithium battery used or renewed — capacity will have degraded from the rated figure.
Sources: Harman Kardon Onyx Studio 3 & Onyx Studio 4 spec pages (drivers, power, battery, Bluetooth, weight, pairing); AudioReputation Studio 3 (real-world runtime); Amazon owner reviews, Onyx Studio 4 (B074P79X9C) (passive radiator, ~4h high-volume runtime, “sound the same”). Manufacturer “up to” figures are labeled [HK].
The two speakers, in depth
Both are discontinued, so prices are used/renewed and move around — confirm availability and battery condition before you buy.
Harman Kardon Onyx Studio 3
The Studio 3 gives you the same iconic Onyx look and the same 60W sound as the 4 — 2×75mm woofers + 2×20mm tweeters, 50Hz–20kHz [HK] — usually for less, since it’s the older model. It also has a built-in mic with noise/echo cancellation and connects up to 3 devices, one more than the Studio 4 [HK]. The catch is the battery: HK rates it at just up to 5h (2600mAh), and independent testing puts real-world life closer to ~3h at high volume [HK; AudioReputation]. There’s no IP rating, so keep it away from water [HK].
Approx. price: ~$130–$160 used/renewed (new units discontinued)
Harman Kardon Onyx Studio 4
The Studio 4 is the one to get if you can find a clean unit, because it fixes the 3’s biggest weakness. It uses the same drivers and the same 60W [HK] — owners note a rear passive radiator [Amazon owner review] — but jumps the battery to up to 8h (3000mAh), the single biggest upgrade between the two [HK]. It also moves to Bluetooth 4.2, adds Siri/Google voice access via the call button and HK Connect app, and swaps Dual Sound for HK Connect+, which scales to 100+ speakers [HK]. Real-world battery still lands around ~4h at high volume [Amazon reviews], it drops to 2 simultaneous devices, and like the 3 it has no waterproofing [HK].
Approx. price: historically ~$145–$200, now varies (listing live but often “no featured offer” — used/renewed common)
Sound: a genuine tie
This is the part most “Studio 3 vs 4” comparisons overhype. Harman Kardon lists the identical transducer array on both — two 75mm woofers and two 20mm tweeters — and the same 60W total output (4×15W on AC, 4×7.5W on battery), with the same 50Hz–20kHz range [HK]. Owners who have used both report they sound essentially the same [Amazon review]. So if your decision is “which sounds better,” the honest answer is neither — buy on battery, features and price, not on an imagined sound upgrade.
Battery: the one real upgrade
Battery is the headline difference and the reason the Studio 4 generally wins. The Studio 3 carries a 2600mAh cell rated at up to 5h; the Studio 4 steps up to 3000mAh and up to 8h, both quoted at moderate volume [HK]. Treat those as best-case: independent testing on the Studio 3 saw closer to ~3h at high volume [AudioReputation], and Studio 4 owners report around ~4h pushed loud [Amazon reviews]. And because both are discontinued, any unit you buy has an aged battery that has lost some of its original capacity — budget for that, or buy renewed from a seller that replaces cells.
Bluetooth, pairing & voice
The Studio 4 is newer on connectivity in most ways: Bluetooth 4.2 vs the 3’s 4.1, plus Siri/Google voice access through the call button and the HK Connect app, and HK Connect+ multi-speaker linking that scales to 100+ units [HK]. The one place the older Studio 3 wins is simultaneous pairing — it holds 3 devices to the 4’s 2 [HK]. Neither carries an IP rating, so treat both as indoor, keep-it-dry speakers [HK].
Availability: read this before you buy
Both the Onyx Studio 3 and 4 are discontinued, and that shapes the whole decision. New stock is largely gone; the Studio 3 shows up used from around $139.99, and the Studio 4’s listing is often live but with “no featured offer,” meaning used or renewed sellers. You can absolutely get a great speaker this way, but you’re gambling on a years-old battery either way — which is exactly why, if you want a warranty and a fresh cell, the current model below is the smarter buy.
Harman Kardon Onyx Studio 8 — the buy-new alternative
If you’d rather not gamble on a years-old battery, this is the model to get. The current Onyx Studio 8 delivers 50W stereo, modern Bluetooth 5.2, up to 8h battery, and automatic room self-tuning that adjusts the sound to your space [RTINGS; HK]. Crucially, it’s still in production — so you get a fresh battery, a manufacturer warranty, and current Bluetooth, none of which the discontinued Studio 3 or 4 can promise. It’s the honest “skip both and buy current” pick.
Availability: sold new (buy-box fluctuates new/renewed; a Renewed listing also appears)
Bottom line
Between the two, pick the Studio 4 for the same Onyx sound with meaningfully longer battery (up to 8h vs 5), voice access, and the option to chain many speakers — if you can find a clean used/renewed unit at a fair price [HK]. Pick the Studio 3 only if it’s clearly cheaper and you’ll mostly keep it plugged in, or you specifically want 3-device pairing [HK]. Be realistic: both are discontinued, so you’re gambling on a years-old battery either way.
Want a warranty, a fresh battery and modern Bluetooth? Skip both and buy the current Harman Kardon Onyx Studio 8 — 50W, BT 5.2, up to 8h, room self-tuning, sold new [RTINGS; HK].
Keep going — find your next speaker
Shopping portable Bluetooth speakers more broadly? These guides take it from here:
- 🎉 Need it for a party or big space? → our best party speakers
- 🔀 Wondering how Harman Kardon stacks up against JBL? (same parent company) → Harman Kardon vs JBL, explained
Still torn between the 3 and 4? For most people the honest answer is the Studio 4 if it’s cheap and clean, otherwise the current Onyx Studio 8 for the warranty and fresh battery.
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Frequently asked questions
- Do the Onyx Studio 3 and 4 sound different?
- Not really — HK lists identical transducers (2×75mm + 2×20mm) and the same 60W, and owners who've used both report they sound essentially the same [HK; Amazon review].
- What's the biggest difference between the 3 and 4?
- Battery life — the 3 is up to 5h (2600mAh), the 4 jumps to up to 8h (3000mAh). The 4 also adds BT 4.2, voice assistants, and HK Connect+ [HK].
- Are the Onyx Studio 3 and 4 waterproof?
- No — neither carries an official IP rating from HK. Keep both away from rain and splashes [HK].
- Can I still buy the Onyx Studio 3 or 4 new?
- Generally no — both are discontinued, so most listings are used or renewed (the Studio 3 used from ~$139.99). For new with a warranty, look at the Onyx Studio 8 [HK; Amazon].