Sangean HDT-1X HD Radio Tuner ($250): www.sangean.com.(AUDITIONS)(Product/service evaluation)

This unit and its predecessors have popped up in Ramblings in the last two issues of TSS. I am still in mini-review mode because this new, updated unit has been in the lab for only a week (the original unit has been here for six months). Sangean makes the only full-sized component HD radio tuner of which I am aware. Most HD radio receivers are table radios or in-dashboard units. This HDT-1X not only receives the main radio signal, but also captures up to seven sub channels. In theory, your NPR station could broadcast news, classical, and jazz on the same band, though sound quality degrades in the sub channels. The main channel of an HD FM signal sounds better than XM when reproducing classical music. The secondary HD signals are of similar quality to XM.

The HDT-1X has additional features if your incoming signals are weak:

1) Force analog mode for marginal HD signals Since HD Radio is digital, its sound quality does not correlate with distance from the station. It is go or no go. HD signals drop out well before the analog does, so an HD tuner switches to analog if the on-band HD signal fades away and then goes back to HD when the signal improves. This transition is not seamless: the tuner keeps dropping in and out of HD when you are in a marginal area with respect to the HD reception. The force-analog mode prevents hunting by locking-out the HD mode from the tuner. You lose the advantages of HD, but gain a listenable signal.

2) Force Mono

As you move further away from an FM station's antenna--well past the point from which HD can be received--noise from the analog MPX stage becomes unacceptable. The solution is the same since the first analog stereo tuners appeared in the 1960s. This solution was missing from the original design, rendering some stations unlistenable.

The price of the Sangen is surprisingly low given its sophisticated Texas Instrument's chip set. The small double-sided PC board has electronics stuffed on the top and bottom. All the DSP processing in the TI chips outperform even the most ...