Valves can be a bit troublesome. If you're lucky big ones responsible for producing power will last a few thousand hours, but then need replacing. However, small ones that don't dissipate power will soldier on past 10,000 hours – and what's more they cost little, in the £10-£20 region. No wonder then that manufacturers nowadays use transistors to produce power, but use small valves elsewhere in a hybrid amplifier. The sound is a bit of a compromise, but one worth making, especially since transistors give tighter sounding bass. A lot of advantages then, explaining why McIntosh of the US went down this route with their new MA352 hybrid amplifier reviewed in this issue – see p10. Our pictures show just how visually arresting a hybrid can be, especially with a little help from LED up-lighters and illuminated power meters.
Another US brand, Klipsch, have a different take on traditional style. Their Heritage Series The Sixes we review on p43 hark back to Klipsch speakers of yesteryear, are compact yet fully powered and accept just about any signal source you may have, from old tuner to modern turntable – not to mention digital sources including a computer, or portable phone with Bluetooth wireless. As reviewer Jon Myles notes, at the price this all-in-one is remarkable – and was admired by all who heard it at our offices.
Today we tend to take digital for granted, but not so long ago the technology was challenging, as Martin Pipe makes clear in his in-depth look at Aiwa's HD-S1 digital audio tape (DAT) machine on p50. The analogue-to-digital convertor (ADC) was an extra, it was so complex and expensive, early digital recordings made for CD being equally challenged in cost and capability. We tend to forget how quickly and comprehensively electronics has developed over the last 30 years or so; what lies under the bonnet nowadays is a lot slicker than Aiwa could have imagined back then, bringing great improvements in sound quality – especially to digital recordings.
Anything that can improve digital sound is welcome, and there have been some remarkable innovations such as the million-tap digital filter within Chord Electronics M-Scaler. Another approach is to re-clock in order to remove jitter and noise from a digital stream and this is what you can read about on p34 with Mutech's MC3+USB. It is a tad technical as hi-fi goes but anyone able to read the handbook's dense text should get it and can then be entertained by the benefits of re-clocking. And they are quite obvious, even with digital in decent condition I found.
Old and new vie with one another nowadays, to bring improved sound – often with olde-worlde appearance. You can read about both in this great issue of Hi-Fi World. I hope you enjoy it.