Two TSO-C139a ANR headsets side by side, using Bose’s and David Clark’s own specs, with Amazon prices and stock checked Oct 29, 2026.
By Pilot Gear Compare · How we pick · Last reviewed Oct 29, 2026 (ET)
What changed: Oct 29 Amazon recheck (A30 $1,299 In Stock; ONE-X MAP-hidden $995 In Stock), FAQ schema (Oct 29, 2026).
Quick answer
Both are over-ear ANR headsets with Bluetooth, TSO-C139a and a 5-year warranty. They differ on ANR control, weight, battery hours, plug options and price.
Specs from each maker’s own pages. Amazon prices and stock checked Oct 29, 2026, about 11:44 PM ET; prices change, so use the button for the live price. No Prime-only prices were showing for these listings.
The two weights are measured differently: Bose gives on-head weight, David Clark gives weight without the cable. David Clark lists 30 dB peak ENC attenuation at 150 Hz and ~1.4 lb (6.2 N) contact pressure; Bose publishes neither figure, only that the A30 clamps 20% less than the A20. On Oct 29, the ONE-X listing showed In Stock at a MAP-hidden featured price; confirm the live seller.
What differs
ANR control: the A30 has three user-selectable noise-cancellation modes. The ONE-X uses hybrid feed-forward and feedback ENC with no mode selector listed.
Weight and packing: David Clark lists ~12.3 oz without cable and a collapsible design with a bag. Bose lists 14.2 oz on head and a carry case.
Battery: up to 50 hours on the ONE-X; 45+ hours on the A30, or 25+ with Bluetooth running the whole time.
If the batteries die: David Clark says the ONE-X keeps full communication (fail-safe).
Plugs: the standard ONE-X is dual GA, with panel-powered versions as separate part numbers. The A30 comes in dual GA, 5-pin XLR, U-174 and 6-pin LEMO.
Cable and mic: the A30’s down cable and mic swap sides without tools. The ONE-X boom is full-flex and reversible.
Price: $1,299.00 versus a MAP-hidden featured $995.00 on Amazon on Oct 29, about a $304 gap. Third-party AOD offers were around $1,064 on that check.
Fit is the part specs cannot settle. Public threads on r/flying split both ways on comfort and seal between these two (for example this one and this one). David Clark offers a 30-day money-back guarantee; on Amazon, check the seller’s return window before you order.
No. Amazon also sells a wired A30 at the same $1,299. The button here goes to the Bluetooth version (listing title “Bose A30 Bluetooth Aviation Headset”). Read the title before you buy.
Are both headsets TSO-C139a?
Yes. Bose lists TSO-C139a on the A30 and David Clark lists TSO-C139a on the DC ONE-X. That is the shared certification path that separates this pair from non-TSO Lightspeed Zulu models on our Zulu 4, Zulu 3 and Bose A30 compared guide.
Which is lighter?
Bose lists the A30 at 14.2 oz on the head. David Clark lists the ONE-X at 12.3 oz without the cable. The two weights are not measured the same way, so treat them as maker figures, not a lab compare.
Specs come only from each maker’s own product pages and data sheets, listed below. Prices and stock come from Amazon on Oct 29, 2026, about 11:44 PM ET. This is a spec-based comparison: no hands-on test was done for this page, and fit is personal, so use each maker’s or seller’s return window to try a headset in your own aircraft.
