Astro A40 Review: A $129.99 Open-Back Wired Headset, Off the US Catalogue

$129.99 buys a wired headset with open earcups and no electronics inside. Nothing about it powers up and nothing pairs. One 3.5 mm plug carries the audio out and the microphone back. Logitech's dropped it from the American catalogue and still ships it in South Africa, which is how a live price ends up sitting beside the word Discontinued on a dealer's card.

The third-cheapest open back in the collection

Fifty-seven of the 67 headphones collected here carry an enclosure field, 19 of them open-backed and 38 closed. The open nineteen are mostly studio and audiophile models: an HD 800 S at $1,999.95, a Focal Utopia at $4,999, an Audeze LCD-X at $1,199, a K702 at $429. Two open backs undercut $129.99: a SHOKZ OpenRun Mini at $129.95 and a semi-open AKG K240 Studio at $79.

And that's the whole point of the design. An open earcup costs less to build than a sealed one and sounds wider for the money. But it also leaks in both directions, which is why the rest of the open list lives in quiet rooms rather than on a sofa. Astro sold the arrangement to gamers instead of to mixing engineers, and that's what the swap looks like in the price.

Four gaming headsets sit in this collection and three of them are open-backed. The wireless Astro A50 Gen 5 at $299.99 carries the same classification on its dealer card and nothing else confirms it. So this is the only gaming headset here whose maker prints the word open in its own specification.

Two spec sheets, and the cable is the only line between them

Logitech publishes a specification page for the Gen 3 headset and another for the Gen 4. Nine technical rows appear on both: 3.5 mm 5-pole mini-stereo with a PC splitter, distortion under 0.1%, over-ear coupling, 20–20,000 Hz, headband pressure 2.6 N, a 6.0 mm unidirectional microphone with a noise gate, 48 ohms nominal, a dynamic open 40 mm driver, 369 g without cable. And every figure matches word for word.

One row differs. Gen 3 ships a 1.5 m PC splitter and a 1.0 m mobile cable. Gen 4 ships the same splitter and a 2.0 m cable with an inline mute switch. That's the entire published difference between two generations of the same product.

The dealer's card records a single cable length, 3.28' / 1 m, which is the Gen 3 figure printed against a Gen 4 part number. Neither card mentions the splitter at all, so a buyer reading only the listing doesn't learn about the other.

A 2.4 GHz radio on a headset that takes no power

Here two cards at the same dealer sell this headset in different colours. They don't carry the same fields. The black and blue one adds four the red one lacks. It names a 2.4 GHz radio link, a 2× 3.5 mm Y-splitter as an included adapter, a cable called detachable, and active noise cancellation marked No rather than not specified.

The radio is the interesting one, because the card refutes itself two rows later. Charging Input on the same page reads Passive Headset-No Power Required, wireless charging reads No, and the only connector listed anywhere is a 3.5 mm TRRS jack. A passive headset hasn't got anything to run a transmitter on. Both of Logitech's specification sheets list one connection, and it's the cable.

A contradiction inside one listing says something a contradiction between two listings doesn't. It shows a field filled by template rather than by the product. That's the failure mode worth carrying to the next card. Nothing about the sentence looks wrong until the neighbouring row is read. And the same fault reaches further up than the shop. HyperX heads two different sections of its own table with the identical words, Headphone Specifications. The second of the two is the microphone, so there it's the maker's template.

48 ohms, 40 mm, 369 g

Forty-eight ohms is exactly the median of 30 over-ear models here. The spread behind that median runs from 18 to 470, and the 40 mm driver lands on the median too, across 26 models that name a size. But neither figure separates this headset from anything.

Weight does. At 369 g it is heavier than 27 of the 36 over-ear models with a published weight, where the median sits at 289 g, but lighter than only eight. A boom that unplugs and remounts on either cup, magnetic speaker tags on both sides and a headband built as a separate sprung arch are where those extra 80 g go.

The figure that almost nobody publishes is the one worth reading: headband pressure, 2.6 N. Clamping force decides whether an open cup seals enough to hold bass and whether an hour is comfortable, and it's the number makers leave out precisely because it's easy to compare.

But frequency response is the opposite case. Twenty to 20,000 Hz arrives with no tolerance attached, and it's the commonest pair here: six cards print exactly those two numbers, the A40 and the A50 among them. On the A50 card a second Frequency Response row underneath prints 60 Hz to 20 kHz. That one belongs to the boom microphone rather than to the headphone. A Yamaha HS5 publishes 74 Hz at −3 dB and 54 Hz at −10 dB side by side, which is what a range looks like when its basis comes with it.

The dealer's table splits into labelled Headphone and Microphone sections, and the 20 Hz figure sits under Headphone, while the microphone section carries a 6 mm diaphragm and a cardioid pattern, and doesn't carry a range at all. A Sennheiser Momentum 4 fills both halves of that same split, 6 Hz to 22 kHz for its speakers against 50 Hz to 10 kHz for its microphones, and that's how a flat read of either table ends up filing a headset at its microphone's numbers.

A capsule that publishes no band hasn't got anything to be ranked against. A Sennheiser e835 handheld prints 40 Hz to 16 kHz at $99.95, and the boom on this headband declines that comparison by publishing no figure to enter it with.

Xbox One on the spec sheet, Series X on the shop page

Both Logitech specification pages give the same compatibility line: PC, Mac, Switch, Xbox One, PS4. But Logitech's own storefront describes the identical product as compatible with Xbox Series X|S, PlayStation 5, Switch, PC and Mac. The dealer's card follows the spec sheets and lists Xbox One and PlayStation 4.

And nothing in the headset changed between those documents, because there's nothing in it to change. An analogue plug hasn't got a protocol to be compatible with. A compatibility list on a passive headset records which controllers carried a headset jack on the day the document was written, and the newer list is right for the same reason the older one was.

Off the American catalogue, in stock in South Africa

Logitech's American gaming audio catalogue holds 20 products and none of them is an A40, and Astro is represented by the A20 X, the A50 Gen 5, the A50 X, the A10 Gen 2 and the A20 Gen 2, and the direct address of the model's own page redirects to that list. The South African storefront sells it as Black/PS, part 939-001664, marked in stock and ready to ship, though with no price in the markup at all.

The dealer keeps both colours at that price with availability set to Discontinued. Five owners rate the black and blue listing at 5.0, while the red X-Edition card carries none at all.

Six of the 67 headphones here are marked discontinued, though every one of them still carries a price. That's a quiet problem for any ranking built on dealer listings. A dead model holds its last price forever and drifts down into the cheap rows where nothing can be bought. An Audio-Technica ATH-M50 shows how firmly those prices set: two unrelated shops both print $139.00 beside a discontinued status, to the cent, and an Audio-Technica M50x at $159 is the closed-back wired answer that's still being made.

What the sheets answer about the A40

Is the A40 wireless?

No. Logitech lists one connection, a 3.5 mm 5-pole plug with a PC splitter, and the dealer's own card marks the headset passive and requiring no power, while one of that dealer's two cards also prints a 2.4 GHz radio field, and it contradicts the same card two rows down.

What is the A40's frequency response?

Twenty to 20,000 Hz, with no tolerance stated by anyone. The figure belongs to the drivers, while the microphone section of the dealer's table doesn't publish a range.

Does the A40 work with a PS5 or an Xbox Series X?

Logitech's shop page says yes, but its specification sheets stop at PS4 and Xbox One. The plug is analogue. So the answer doesn't depend on the headset, but on the controller having a jack.

What cable comes with the A40?

A 1.5 m PC splitter in both generations, plus a 1.0 m mobile cable on Gen 3 or a 2.0 m inline mute cable on Gen 4. But the dealer's card lists only the shorter one.

Is the A40 still sold?

Not by Logitech in the United States, where the model's left the catalogue. The South African storefront still lists it in stock, and dealers hold remaining stock at the old price.

Where $129.99 of wired headset makes sense

A quiet room and a machine with a headset jack. Open cups, 48 ohms and a 369 g frame with no battery in it answer that setup completely. The mod kit both dealer cards describe, with closed-back tags and leather cushions, exists because the open version answers nothing else.

But everything that makes it cheap makes it narrow. Sound leaves the cups, room noise comes in, and a console without a jack on the controller leaves the plug with nowhere to go. The absence of electronics is the same fact read twice: nothing to charge, but nothing to switch.

So what it competes with now is its own stock. The model is off the American catalogue and the price on the listings is the last one it had. So the comparison is no longer against a current headset at $129.99 but against whatever is left in a warehouse.

Price and specifications

Sources

1. Logitech's specification page for the A40 TR Gen 4: connection, distortion, ear coupling, frequency response, headband pressure, microphone size and pattern, nominal impedance, driver type and size, weight, compatibility list, and the contents of the box including the 1.5 m splitter and the 2.0 m inline mute cable.
2. Logitech's specification page for the Gen 3 headset: the same nine technical rows, and the 1.0 m mobile cable that is the only line separating the two generations.
3. Logitech's own storefront for the model, South African region: availability, part number, colour, weight to two decimal places, cloth cushions, the microphone that mounts on either side, and the compatibility claim naming Xbox Series X|S and PlayStation 5.
4. B&H Photo Video listing for the X-Edition: price, availability, the magnetic speaker tags and the mod kit that replaces them with closed-back ones, and the specification table read section by section, with the frequency response row under Headphone and no range under Microphone.
5. B&H Photo Video listing for the same headset in black and blue: price, availability, owner rating, the platform list, and the four extra fields including the 2.4 GHz radio that the same card contradicts.
6. Logitech's American gaming audio catalogue, loaded to all 20 products: which Astro models remain in it, and which one no longer appears.
7. Medians, row sizes and positions come from listings of 200 audio products collected the same way. How those are converted and compared.

21 August 2026 is the day these shop pages were read, and the prices belong to it alone.

What we did not do

This headset has never been on our heads. Every figure above is Logitech's or its dealer's, and what we add is the ranking: where each number sits among the models collected here.