This article is from the Aviation FAQ, by Geoffrey G. Peck firstname.lastname@example.org with numerous contributions by others.
There are three types of aviation headsets which are commonly available:
1. Active noise-cancelling (ANC). These are in the $600-$900 range,
from Telex (ANR, ~$660; the ANR 4000 is not recommended), David Clark
(~$850), and Sennheiser (~$700). The Bose headset (~$900) is
available only directly from Bose in Framingham MA.
2. Passive noise-cancelling. These are in the $90-$300 range, and
come from a variety of manufacturers. David Clark is generally
regarded as the "Rolls Royce" of headset makers, and their models are
more expensive than the competition -- they stand up to amazing
abuse. Recommended models include the H10-13.4 (13.4 oz -- light!)
~$245, H10-60 ~$250, H10-20 ~$225, H10-80 ~$245, and H10-40 ~$220,
usually in that order. The H10-30 is not recommended (inferior
microphone). A number of companies import "clones" of the David
Clarks; many netters have found the Flightcom 4DLX, ~$120, to
be satisfactory in terms of performance and reliability. There are
many, many more makers out there -- try 'em on and see what feels
comfortable to you. Other notable headsets: Peltor 7004 ~$190,
which has a significantly different and possibly more comfortable
"feel" -- buy it in preference to the 7003, which has an inferior
dynamic microphone; Pilot PA11-20 ~$140; Telex Pro-Air 2000E, ~$225.
The Peltor is probably the best choice for kids.
3. "Open-air," "Walkman-style". These are for quieter aircraft such as
jets or sailplanes, and are _not_ recommended for prop aircraft use.
[Headsets are typically discounted; prices given above are typical US$
discounted prices, not list. See Q7 below for mail-order supply houses.]