I have bought the A30, from Peter Mundy’s shop. Super fast service.
Lemo plug version.
The reduction in the ANR hiss (which is a byproduct of ANR, and is very noticeable in practically all ANR headphones) is dramatic; there is almost none.
Whether the hiss reduction does anything in flight, I cannot tell, because the ambient noise level is plenty high enough to swamp the hiss of the X or the A20.
The headset feels a bit more comfortable than the A20.
The mike boom is thinner and easier to bend.
The mike has slightly less gain than the A20 but works fine.
A welcome improvement is that the Lemo plug version does not need to be manually turned on. The A20 stupidly needs to be manually turned on even though aircraft power is available.
I could not readily detect a difference in the audio quality, by repeatedly swapping the A30 and the A20. But there could be one; (a) I am 66, and b) such a comparison is hard to do without replaying the same audio.
For anyone upgrading from some other headset, going for the A30 is a no-brainer.
I haven’t got a D-C.
Why would I be biased? I just told it straight.
Years ago I compared a top end D-C against the Bose-X and the Bose was way better, way less clamping force, etc. The sole advantage of the D-C is that you could sit on it, stand on it, drop it from FL200, and it would still work, so good for the rental business. And good for single door planes where people have to climb over the seats to get in, and step on stuff 
And the A20 is way better than the X; when I started on the A20 I kept checking the engine instruments!
Had to google on Cool Aid: What does Kool-Aid mean in slang?
“Drinking the Kool-Aid” is an expression used to refer to a person who believes in a possibly doomed or dangerous idea because of perceived potential high rewards.
It is a reference to rhe Jonestown massacre, where cult members drank poisoned fruit juice.
I always took it as a reference to losing touch with reality and doing something stupid through courage in your convictions.
The A20 stupidly needs to be manually turned on even though aircraft power is available.
That is totally wrong. I have 4 of them in different aircraft types in the last 10 years, one need to read the manual and switch on the small slider in the box, where ‚auto on‘ is signed!
privateflyer – we need you to drop in here more often than 1x or 2x per year This has come up lots of times before.
Back to the A30, the main reason I bought it was to see if it delivers better clarity i.e. a better frequency response. Haven’t done enough testing yet; time will tell.
I have an A20 and love it, standard aviation plugs so I need to keep up with the batteries and turn it on manually (like an animal!) but if I were getting a new headset I’d look very closely at the Lightspeed Delta Zulu – it has built-in CO detection, and can adjust frequencies depending on your hearing loss. Two pretty cool features.
My LEMO plug A20s also turn on automatically. The battery compartment has a small switch to turn the “Auto ON” feature on or of..
The first version of the A20 Lemo cord did not have Auto-On. Starting in 2015 or if you swapped out the cord they do.
@privateflyer can you point out the switch you referred to?
That is totally wrong. I have 4 of them in different aircraft types in the last 10 years, one need to read the manual and switch on the small slider in the box, where ‚auto on‘ is signed!
