The HEIL Sound Pro7 headset has two large gel earpieces for a comfortable fit, also
during extended wearing time, which also ensure a high level of
suppression of ambient noise: 26 dB attenuation according to
The headset is stereo, so that
signals from two receivers (pileup and Dxpedition) can be listened to
and leveled out via the integrated balance controller separately.
with all other larger HEIL headsets there is a switch for one-sided
phase reversal to turn the received signal 'in your head', and also to
ease symptoms of fatigue during contest.
Pro7 headset has a detachable connecting cable and is available either with HC-7 dynamic microphone capsule or with an electret capsule for ICOM.
The microphones are interchangable so that one headset for both
equipment lines can be used.
The dynamic HC -7 element has a frequency response of 100 Hz - 12 kHz with the -3dB points at 100 Hz and 12 kHz. The traditional healing speech enhancement is centered at 2K - 4KHz. The impedance is 600 Ohms.
The iC electret element designed for ICOM radios has the -3dB points at 35 Hz and 12kHz with a sensitivity of -48 at 1500 ohms output, centered at 1kHz. The IC element solves the problems with older Icom radios (before IC-756) with low gain, but can also be used with newer Icom models with excellent results. To operate the iC-electret element a bias voltage is applied.
The Pro7 headset is available in different colours.
The optional HC-74 capsule (orange) is a further development of the very popular HC-4 microphone capsule. It was developed to meet the high demands of demanding DXers and contesters. The low frequencies are softly limited from 600 Hz, in the frequency range of 2500 - 3000 Hz, which is important for intelligibility, the level is increased by approx. 10 dB. This produces a very concise SSB signal that is easily audible even in the thickest pileup.