Marantz PM6010 OSE KI Signature Amplifier

The KI Signature version, named for Ken Ishiwata, Marantz's resident electronics whizz. In common with the rest of the small but select band of Kl Signature models, a number of enhancements have been made to improve sound quality.

The PM6010OSE has a plain aluminium slab fascia, with a thin leavening of controls, including a massive rotary volume control and a four position input selector (moving magnet phono, and three line level inputs). There are three buttons to select tape monitor, a single input described as CD-R/MD, and a source direct feature, which bypasses the balance control and the other switching. Remote control is included.

The package of enhancements over the standard PM-6010OSE includes a complete copper plated chassis, a toroidal transformer with OFC windings, and what are described as a great deal of component substitutions to suit - including capacitors, resistors and rectifiers, all chosen by careful listening. Other features are carried over from the original, including an extruded low resonance front panel, solid independent L/R heatsinks, and a triple Darlington output stage capable of 100 watts into 2 Ohms.


While there were plenty of specific criticisms, they were quite scattered and - as so often with amplifiers that don't tweak the listening bone in quite the right way - the predominant feature to emerge was a general feeling of unease. 'It's too thin,' wrote one panellist, while another described 'big dollops of sound' - both referring to the Bach recording. Similarly, Tracy Chapman was felt to have plenty of depth by one panelist, but was criticized by another for a guitar that sounded as though it had only 'three top strings'. The Liszt piano had a 'poor left hand presence and weight', and one of the sum-up comments talked of an amplifier which 'punched quite well, but without enough substance in the middle for the sound to hang together'.

Perhaps the most interesting, and certainly the most striking, comment was from a listener who thought that the Marantz sounded 'over tuned'. This drew wider agreement in apr?s-listening discussion, a feature of the panel tests, and elicited the response from another that 'it sounds as though it is voiced to be an award winner'. This curious criticism, taken together with other observations and the hands-on listening both before and after the panel test programme, are consistent with the picture of a more focused and hyped up version of the 6010 OSE in which the fundamental limitations of the original have not been addressed. The extra resolution of the new model, which is undoubtedly a factor, serves to do little more than highlight the limitations of the original. I share the view that the sound was a little unbalanced in favour of the mid top, and that it lacked a solid physical foundation. As often happens, though, matters improved with smaller, easier speaker loads, and there was also a feeling that the sound didn't really hang together in a consistent and believable way.


A temping conclusion here is that the Kl programme is hamstrung because the starting point is not of a top standard, which brings to mind the adage about silk purses and sow's ears. While the PM6010OSE KI is no sow's ear, it is no silk purse either, and it is not entirely easy to build fully satisfying systems around it.

Marantz PM6010 OSE KI Signature Amplifier photo