Pre/Power Amplifiers

The first product from a new Japanese high-end marque, this imposing hybrid power amplifier system employs a ‘DC reactor’ power supply housed in a separate chassis Rarely does an amplifier designer launch a new hi-fi company with such a bold high-end statement. ‘This is our vision of amplification’s ultimate form’, says designer Robert Koch of the imposing ‘tri-chassis’ Takumi K-70 power amplifier, designed and built in Japan, and the very first product to sport the Robert Koda brand name on its fascia. The Japanese ‘Takumi’ character can be translated as ‘maestro’, while the word ‘takumi’ actually means artisan – the naming of the Takumi K-70 being particularly apt as the amplifier is wholly hand-crafted, and manufacturing is limited to just 20 units per year. It’s a single-ended hybrid design employing some 32 power transistors and two 5842 triodes in each monoblock and one 6X5 rectifier tube per side in the power supply.

With the C-600f preamp and the M-600A stereo power amplifiers, Luxman has delivered its interpretation of current generation solid-state excellence. The power amp offers balanced or single-ended operation, the option of converting it into a bridged monoblock of up to a specifi ed 120W/8ohm, plus a couple of neat touches on the back. Like all new Lux products, an indicator tells you with the press of a button if your mains polarity is correct. Another rear panel delight is a quartet of the largest speaker terminals I’ve ever seen, a nod to those who like tight terminals, but with an aperture for banana plugs.

Bottom of the five-model XA. 5 series of mono power amplifiers, all of them true Class A designs, the XA60. 5 offers a rated output of 60W and, it’s claimed, much higher current capability than previous XA models: to the tune of a fi ve-fold improvement. So tough loudspeaker loads, of which there are still many, are grist to the XA.

Radford Electronics was set up in Bristol by Arthur Radford back in 1959. In some ways Radford was a late starter in the world of high fi delity, especially compared to Peter Walker of Quad or Harold Leak, and the electronics refl ect this. Indeed, Radford’s designs are often described as being the most ‘modern’ of vintage amplifiers. It was the Series Two amplifiers, soon changed to Series Three, that put Radford’s designs on the map, the Series 3 range comprising two monoblocks – the MA 15 and MA 25 – plus two stereo versions, the STA 15 and STA 25.

You could have knocked me down with a feather when, late last year, I received an e-mail from Adrian Walker, one half of the dynamic duo behind the original Deltec Precision Audio. I had used DPA’s 100S pre/power combination for the best part of a decade in my own system, and reviewed the inaugural product in HFN Oct ’87, but the company had dropped off our collective radar by the late 1990s. Rob Watts, the pioneering engineer behind the outfit, had moved on to other projects including a now longstanding relationship with Chord Electronics. Yes, Rob Watts ex- of DPA is the same Watts behind the WTA digital filter used in Chord’s Red Reference CD player.

Class A operation has a noble history. Thanks to the always-on nature of the topology and the removal of an entire type of distortion, allied to sound that excels in low-level detail, superb dynamics and transparency, its devotees are more than happy to put up with low efficiency and heat. From Sugden to Levinson to Krell, and here to Belles, it’s a choice for connoisseurs. Should the escape of all that heat come to the attention of Brussels, the EU might then outlaw Class A amps as they have light bulbs.

John Howes has been tweaking, modifying and restoring vintage hi-fi equipment long enough to have a healthy approach to the purity of spot-on restorations. It’s a philosophy he applies to the customising of Quad’s classic II mono valve power amplifier. Because he’s also a realist, he also knows how to recognise if a product is a basket-case, useful only as a donor for spares. As the original sold well over many years, there are sufficient beyond salvation.