Marantz PM-11S1 (2004)

Name: Marantz PM-11S1
Brand: Marantz

The Marantz PM-11S1 is a reference-grade integrated amplifier released in Japan in July 2004 at ¥350,000. Marantz spent two years developing it as a pre-main amplifier that explicitly inherited the design concept of the company's separates - the SC-7S1 preamplifier and MA-9S1 power amplifier.

The amplifier is built around Marantz's HDAM SA2 modules, described as an evolution of the HDAM SA found in the SC-7S1/MA-9S1. They are used throughout for current-feedback phono, balanced buffer, line buffer, volume, voltage, and power buffer stages. The power amplifier section follows the MA-9S1's architecture of two separate amplifiers: an 11 dB voltage stage and a 12.5 dB power buffer. The split is meant to keep speaker back-EMF from reaching the voltage gain stage. Rated output is 200W + 200W into 4 Ω and 100W + 100W into 8 Ω (20 Hz-20 kHz, both channels driven), with THD rated at 0.01%. Frequency response runs from 5 Hz to 120 kHz ± 3 dB at 1W into 8 Ω.

The Floating Control Bus System (F.C.B.S.) synchronizes up to four PM-11S1s over high-speed bidirectional communication, for bi-amplified or multi-channel setups. The volume uses the same linear control design developed for the SC-7S1, adjustable from 0 to -100 dB with ±0.5 dB accuracy. The phono stage supports both MM and MC cartridges and uses a current-feedback circuit, a first for Marantz at the time. The front panel is solid aluminum in a three-piece construction with aluminum side panels. Controls are illuminated in blue behind a low-noise LCD display. A choke-input power supply feeds the preamp section. The power stage draws on a shielded super-ring toroidal transformer with 18,000 μF capacitors and Schottky barrier diodes, capable of roughly 50A of instantaneous current. It weighs 26 kg and measures 440 × 165 × 444 mm, so it is a substantial piece of equipment.

The documentation record is decent on specifications but thin on reception. No period reviews from major English-language publications have surfaced in the archive. One owner on a Russian forum remarked that the PM-11S1 plays any music with a magnificent soundstage (Avito listing, translated). Another noted it was released in 2004 and would likely sound better if nobody had been inside it (forum.ixbt.com). A single user manual rating of 8.3 exists on manuals.co.uk. Current market listings appear on eBay, Audiogon, HifiShark, and Catawiki, with asking prices ranging from a $2,500 Audiocircle listing to various others without visible prices.