ACCUPHASE AD-2900

The AD-2900 is presented as a dedicated phono equalization unit designed to enable high-quality playback of analog records when installed in a rear-panel slot of compatible preamplifiers. The device integrates separate input circuits for MC and MM cartridges, ensuring optimal matching with different cartridge types and achieving a particularly high signal-to-noise ratio.

It features two turntable inputs, labeled AD1 and AD2, selectable via the INPUT selector of the preamplifier, allowing connection of up to two tonearms or analog sources. The internal architecture employs circuit boards made of fiberglass and fluorocarbon resin, with complete separation between left and right channels, while the differential-type equalization stage ensures an extremely precise RIAA curve.

For MC cartridges, a low-noise bipolar transistor differential circuit is used, whereas the MM section is optimized for quiet and stable performance, contributing to high signal purity. The module also offers dual gain adjustment, set at 64 or 70 dB for MC and 34 or 40 dB for MM, with MC input impedance selectable among 10, 30, 100, 200, or 300 ohms and MM input impedance fixed at 47 kOhm.

Depending on the preamplifier model with which it is used, the availability of MC impedance settings may vary, while still providing multiple matching options to ensure compatibility and operational flexibility. The unit is compatible with numerous preamplifiers of the same series, including the C-2900, C-2850, C-2820, C-2810, C-2800, C-2450, C-2420, C-2410, C-2400, C-290V, and C-290, integrating coherently with their signal management functions.

All functions can be controlled from the front panel, and dedicated memory settings are provided for each input, while the robust aluminum chassis effectively shields the system from external interference, ensuring stable and consistent performance.

Technical specifications:

• Dual-mono construction with separate circuits for left and right channels, designed to minimize crosstalk and ensure extremely high channel separation
• Circuit boards made of fluorocarbon resin with a fully independent architecture for each audio channel
• Separate amplification stage configuration with distinct signal paths for MC and MM sections
• MC stage based on ultra-low-noise bipolar transistors and MM stage based on JFET transistors, both optimized for maximum signal purity
• High-precision differential RIAA equalization stage for extremely accurate frequency response
• Selectable gain for cartridge matching: MC 64 dB or 70 dB, MM 34 dB or 40 dB
• MC input impedance adjustable across multiple values (10, 30, 100, 200, 300 ohms) for proper matching with compatible Moving Coil cartridges
• MM input impedance fixed at 47 kOhm
• Two independent gold-plated RCA analog inputs (AD1 and AD2), allowing connection of two turntables or separate tonearms
• Independent settings management for each input, with configuration memory storage
• Direct control of functions from the host preamplifier’s front panel
• Integrated switchable subsonic filter for reducing unwanted ultra-low frequencies and protecting loudspeakers
• Fully shielded structure with a robust aluminum chassis, acting as a Faraday cage against electromagnetic and magnetic interference
• Installation via “Option Board” expansion slot in compatible preamplifiers and integrated amplifiers
• Compatibility with various Accuphase models, including C-2900, C-2850, C-2820, C-2810, C-2800, C-2450, C-2420, C-2410, C-2400, C-290V, and C-290, with possible limitations on older models
• Direct integration into the preamplification signal path to reduce external cabling and minimize signal loss and noise