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.

It looks like the S5 stereo power amp, both inside and out, but the Michi M8 monoblock is altogether more powerful and, as a result, offers a sound with a charm all its own

You'll have to examine the £5399 Michi M8 monoblock power amp very closely to see how it differs from the company's S5 stereo model, reviewed previously alongside the £3299 P5 preamplifier [HFN May '20]. The two are the same price and size, look identical and have much the same 'ask a friend to help' mass. In fact, the M8 weighs marginally less than the S5, at 59.1kg – the difference presumably accounted for by the need for two-channel inputs on the stereo amp whereas the mono version has only single-channel connections, on both balanced XLR and unbalanced RCA sockets.

A sleek new look heralds the return of Rotel's premier sub-brand, and its new control amplifier – or preamp – and stereo power amp have the wherewithal to succeed

Michi is back: last marketed in the 1990s, Rotel's elite sub-brand has rejoined the hi-fi fray after a three-year development project, and the establishment of a dedicated facility within the company's factory to hand-build the new products. And I have to admit to a pang of nostalgia for I reviewed the company's RHCD-10 player, slimline RHA-10 preamp and substantial RHB-10 power amp back in the dim and distant, and it was a case of lust at first listen, not to mention sight of the high-quality metalwork with its red-lacquered wooden side-cheeks.

The arrival of a new British hi-fi brand is a major event. Ivor Humphreys hears Samuel Johnson's 50W-rated pca100/ppa100 pre/power amplifiers

Abrand new company, Samuel Johnson was founded by a group of enthusiasts, most of whom had met through their work with a Scottish-based manufacturer of control systems for industrial applications and who discovered further common ground in a consuming interest in hi-fi.

On seeing Siltech’s pre/power combo you might think it incorporates a separate power supply. In fact, this unusual design splits the power amplifier into separate interstage (voltage gain) and current amplifier sections. The combo’s C1 tube preamplifier (pictured) features a rechargeable battery power supply as does the V1 voltage stage of the two-box power amplifier. Of course, running the complete V1/P1 amplifier from a battery would be wholly impractical, so the P1 is mains powered.

In one swipe, the long-awaited 860A v2 replaces Simaudio's 860A, 870A and 880A power amplifiers and promises 870A performance. We pair it with the 740P preamp

There's something very 'old school' about Simaudio's latest MOON pre/power combination: both units certainly look the part in their combination of black fascias and exposed metalwork, though you can also have them in all-silver or all-black, where they have an air about them of being stripped for action. The £7800 740P preamp, for example, eschews the current trend for digital inputs and network streaming capability, and is a simple, direct, all-analogue line-only affair.