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Where things get even more multiculti is in the fine print. To start with, the musicbook:15 is a fully balanced affair. By definition but often avoided, this must include the volume control as Lindemann do with a balanced laser-trimmed resistor array. This thematic of avoiding redundant conversion (from balanced i/o to single-ended pot) continues with digital. DSD is handled natively, not PCM converted. What's more, the musicbook:15 has a dual engine with two completely separate converters. "Neither ever works in parallel. If converter A is working, converter B is in power-down mode including its clock system and vice versa. The converter outputs are fed to the analog input of the multiplexer and analog volume control. So we have two converters in one box!

"Converter A is designed around a Wolfson 8805 input interface followed by a 4392 SRC and a modified Swiss Anagram Sonic Scrambling DAC based on Wolfson's WM8742 in dual-differential mono mode. This is an intelligent engine which checks incoming signal prior to conversion. 16-bit 44.1/48kHz signal is synchronously resampled to 24-bit/88.2 or 96kHz prior to the Anagram DAC. Signal of higher resolution passes directly. All S/PDIF inputs including the CD drive are finally synchronously resampled to 32-bit/352.8 or 384kHz before being converted to analog by the WM8742. Applied filtering is a minimum-phase apodizer with perfect time-domain response.

"Converter B is exclusive to USB audio class 2 fed by the latest version of the XMOS USB U8 interface. We use a highly stable asynchronous master clock for both the interface and DAC. The USB interface is isolated from the computer power supply and can be updated by USB. Digital data from the XMOS output are direct-coupled to the brand-new Asahi Kasai flagship Verita-range AK4490*. This can process data up to 32-bit/768PMC and DSD256 but the computational power of the XMOS transceiver is still limited to 32/384 and DS128. Since there is no DSP/SRC manipulation, this DAC delivers pure native DSD and bit-perfect PCM. All other data improvements can be handled in the computer. We currently use Audirvana set to isoZote SRC in power of two mode. Now you get exactly the same signal at converter B as you do at converter A!
* As we learn from its press release, "the AK4490 achieves THD+N of -112dB for a voltage output with 120dB dynamic range and integrates a new OSR Doubler switched capacitor filter which greatly reduces sound degradation from noise shaping to achieve a flat noise floor up to 200kHz. A symmetrical layout for the left and right channels prevents signal deterioration and a 32-bit digital operation block provides full 32-bit processing. As a sound quality consideration, the VDD, VREFH, VSS and VREFL pins are separated for each L and R channels. In addition each L and R channel has two pins to avoid common impedance effects and to optimize low impedance performance. Five digital filters cover a short delay sharp roll-off filter and a short delay slow roll-off filter for minimum delay; a sharp roll-off filter and a slow roll-off filter for no phase shift; and a newly integrated super-slow roll-off filter with emphasized characteristics. The AK4490 supports 2.8MHz, 5.6MHz and 11.2MHz DSD and PCM data. It is capable of switching output data between DSD and PCM. Volume pass mode bypasses the volume control block and delta-sigma for DSD to be suitable for applications which have most priority on sound quality. An integrated low-pass filter for DSD meets the Scarlet Book specs with a simple external analog filter. The output level is the same for PCM and DSD."

"If you have an external device like a CD or DVD player, you must do all resampling in hardware. Hence that's what we are doing for the standard digital and CD drive inputs. If you use a good computer playback program on a USB interface, it is always better to do resampling in software for more computational power and higher accuracy**. And the new AK 4490 is a really great-sounding converter especially at high resolutions." The <250fs master clock is of the dual-frequency type to handle the audio/video sample rate families of 44.1/48kHz discretely. The CD drive is a quality Teac slot unit with CD text support. The horizontal volume wheel actually is a multi-function jog shuttle. The yellow-on-black display creates high-contrast OLED graphics with a nearly 180° viewing angle.

** This perfectly tracks my own habits. I always upsample synchronously in PureMusic or Audirvana to take advantage of my computer's 64-bit processing power which exceeds the on-chip math of 24-bit SRCs - Ed

As a clearly smart machine, there's just one global version with mains support from 90-250V at 50/60Hz. It's also a green affair with 0.2W standby draw and 30 watts max consumption. For socketry, digital i/o get two each optical and coax inputs and one each output whilst analog i/o show 2 x 10kΩ RCA inputs and one each RCA/XLR out with 2.5/5V max signal and 100Ω output impedance; plus a ¼" headfi port for 32-300Ω loads. The volume control is segmented in 99 steps in progressively smaller increments. 0-20 uses steps of 2dB, 21-70 gets 1dB and 71-99 0.5dB. Unity gain aka volume control bypass is 14dB or x 5. Bandwidth is DC to 200kHz -3dB. THD+N at full output remains below 0.0005%.
The FMJ wand confirms input prompts with a yellow transmitter LED. That turns red when charging. The deck can be remotely turned on and off. Setup choices include input naming, channel balance, two display brightness modes, enabling of the digital outputs, fixed-out mode and factory default.

CD tracks can be numerically selected with fast forward/back and repeat one/all. The volume up/down buttons double as nav buttons for menu options whilst the OK button confirms a choice. In CD mode the display control shows track and playtime, title or artist. 'Set' up/down switches between inputs or navigates the alphabet to name inputs during setup.
Even headfi volume is under remote control. Manually the jog wheel accomplishes input selection with a press/hold and turn to sequentially shuttle through digital 1-4, CD and analog 1-2. Functionally, the musicbook:15 really is a shoo-in for the company's €6'500 flagship 825 CD player with USB DAC. At €3'200 and rather smaller, it of course aims at a very different customer. And it does more with half by adding preamp and headfi features. Is it the smart-money buy it reads to be as a kind of trickle-down triumph of Lindemann's acknowledged digital engineering? German chaps with digital chops chipping away at the price barrier?