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Radio for High-End Installations (5/7/2004)

By David Harold

42-inch plasma - check. Video distribution system - check. Multi-room 5.1 surround sound - check. DVD and CD transport/source - check. Radio Tuner? Hmm...

There is something about a serious install that makes me wonder whether I should really be listening to 'The Archers' on it. Maybe I should skulk off to the shed and fire up the old tranny. But of course radio is on the up, in all kinds of ways. Even before the advent of new digital radio broadcasts, research had been showing an increase in radio sales. Since DAB digital radio came on the scene the increase has ballooned year on year, making radio one of the hot-sells in consumer electronics. RAJAR (Radio Joint Audience Research Limited) numbers show that overall radio listenership is on the increase too.

It is an older demographic that likes radio - and that tends to mean that a significant number of them are more affluent and more discerning. The trend has perhaps resulted in Radio 2's ascendancy over Radio 1 as the 'most listened to' UK station.

Radio now provides extraordinary novelty, with a rash of new stations spreading across the country. For example, over 50 are available in London on DAB, and both commercial radio and the BBC are having successes with new digital-only stations like BBC Radio 7, 1Xtra, Core and PrimeTime (the Sony Awards' Best Digital Terrestrial Station 2004).

Digital versus FM

DAB digital radio also offers clearer reception and additional DAB broadcast information including station identification, track listings, traffic and news data or other text. In terms of ease of use, it is well ahead of RDS/PTY-equipped FM.

But while radio content and listenership is on the up, new, very high-quality radio hardware is in decline. Radio is mostly sold in sub £150, portable box products, and the wide variety of manufacturers taking advantage of the DAB digital radio market is mostly doing so with mass-market, chain-store devices, predominantly built around the same technology - the Frontier Silicon Chorus DAB module.

Hi-fi quality analogue radio is, as are most high-end audio segments, in decline, with the number of new products decreasing. That is not to say that there are no good tuners out there, but if you already own one, you are unlikely to see the need to upgrade, and the feature-leap being enabled by digital radio is being seen on only a small number of high-end tuners.

On top of this, there is the debate over which radio format is best. Digital may offer more station choice, easier reception set-up, and neat data features, but it is also a 'lossy' transmission format that is closer to MP3 than CD (although still much better than the alternative of Internet radio).

For a lot of fence sitters, the answer has been to stick with a well set-up FM tuner with a good aerial, and perhaps listen to the digital stations available on SKY or Freeview. The problems of this approach to digital radio tend to be in the hardware limitations of the TV set-top-boxes - few of which were designed to offer hi-fi quality - and in the choice of stations. Only a handful of combined DAB/Freeview boxes offer the full range of station choice, and local stations in particular tend to fall off the edge of the listener's world. But at least the key stations will still sound great on FM.

High-quality DAB radios

There are a handful of high-quality DAB radios from manufacturers such as Arcam, Restek and PURE Digital. Some, such as the Restek tuner and the PURE DRX-701ES will complement a separate FM installation, but only a very small number of tuners will cover all the bases such as AM/FM/DAB, high-quality engineering, and a feature-rich suite of functionality and connectivity.

It is a small number, but at least they are out there. For example, the PURE Digital DRX-702ES radio tuner includes: DAB/FM/AM reception; USB connectivity; configurable DAB station ordering (alphabetically, by multiplex, or by favourite/most played); 99 DAB, FM and AM presets; high-sensitivity RF tuner module; low-noise toroidal transformer power supply; fast auto-tune and service selection; RDS support; signal strength meter with diagnostics for easy aerial set-up; and optimised PAC-II technology which results in a significantly more natural sound than other DAB digital radio tuners.

The PURE Digital DRX-702ES radio tuner

With connectivity being a key issue, the best products offer features such as balanced outputs with high-performance balanced line driver circuitry and metal-shielded Neutrik XLR connectors/hard gold-plated output pins, as well as both co-axial and optical digital outputs. Other connectivity should include phono connectors (naturally!); aerial connections for DAB, AM and FM; phono loop-through input; and an RDI (Receiver Data Interface) optical port, as well as USB connection. The DAB output of the PURE DRX-702ES for example, includes high performance 24-bit/192kHz delta sigma digital-to-analogue converters and built-in 4x up-sampling with data interpolation.

Luckily, attractive design is one area in which new digital tuners tend to excel, with stylish precision-machined aluminium front panels, anodised finishes, matching casework details and LED indicators and displays being the norm.

Installation

So what about the actual install? The first key issue is remote control, for which the radio will need to provide codes (HEX or otherwise) for universal remote products, including unique on/off codes. Next up is the aerial, and this will be highly dependent on location. Once a signal is being received, the job is done - digital radio reception quality is not as endlessly 'tweakable' as FM. In strong coverage areas, a paperclip in the back of the radio will provide reception. In weak areas, a directional aerial may be required. DAB-specific aerials are available too, and these have a different length and polarity to FM ones. Taking the aerial feed at least ten inches out from the back of the radio before routing to the aerial itself will improve results significantly.

Naturally the tuner should be isolated as much as possible from other AV components, and connected to a cleaned power source.

The digital future

Digital radio now offers limited data and more station choice. In the future there will be increased features. An EPG (electronic programme guide) is on the cards for early 2005, and rewind and record functions will reach the high-end market too - as they already have in portable products such as The Bug. It is also worth specifying a radio with USB connectivity so that software can be upgraded, and the USB can be used with wireless audio-distribution systems if necessary.

One final note: it is perfectly possible that alongside a tuner installation, the listener might want a few traditional portable radios. After all, there may still be the occasional need to listen in the shed.

David Harold is the PR Manager for PURE Digital, a world leader in DAB digital radio.

www.puredigital.com