Phono Equaliser Unit.
AD-2900 is the dedicated phono equalizer unit. Analog records can be reproduced with high quality by installing AD-2900 in a rear-panel slot. The AD-2900 features separate input circuitry for MC and MM cartridges to ensure optimum matching and realize outstanding S/N ratio. 2 sets of analog-player input jacks, the AD1 and AD2 are equipped, and their selections are switchable with the INPUT selector of pre-amplifiers.
The AD-2900 uses printed circuit boards made from glass cloth fluorocarbon resin, housed in a sturdy aluminium enclosure to minimise any kind of external influence. The input terminals are connected to the amplification circuitry by the shortest possible route, realising outstanding signal/noise ratio. The use of a DIN standard connector for the link to the host component provides enhanced reliability.
Features
- Differential amplifier circuit with ultra low noise bipolar-transistors for MC cartridges.
- Differential amplifier circuit with ultra low noise junction-FET for MM cartridges.
- Differential RIAA equalizer circuit is designed to provide super accurate RIAA equalization characteristics.
- MC Load settings are selectable from among 4 values “10Ω/30Ω/100Ω/300Ω”. The input impedance for both MM settings is 47kΩ.
- Storing separate MC Load and/or AD GAIN settings for each installed AD input (AD1 and/or AD2) is available, and it enables the smooth switching of 2 kinds of analog players or tone arms.
- The printed circuits are made from glass cloth fluorocarbon resin.
Frequency response
- MM/40dB, MC: 20～20,000Hz ±0.2dB
- MM/30dB: 20～20,000Hz ±0.3dB
AD maximum input voltage (1 kHz, 0.005% THD)
- MM/30dB INPUT: 310mV
- MM/40dB INPUT: 96.5mV
- MC/60dB INPUT: 9.5mV
- MC/70dB INPUT: 3.2mV
Gain (Gain selector set to 18 dB position, 12/18/24 dB settings available)
- AD[MM:30/40dB]INPUT → BALANCED/LINE OUTPUT: 48/58dB
- AD[MM:30/40dB]INPUT → REC OUTPUT: 30/40dB
- AD[MC:60/70dB]INPUT → BALANCED/LINE OUTPUT: 78/88dB
- AD[MC:60/70dB]INPUT → REC OUTPUT: 60/70dB
Input sensitivity and impedance
- Input, Input Sensitivity (For Rated Output/For 0.5V Output), Input Impedance
- AD-MM/30 dB INPUT, 8.0 mV, 2.0 mV, 47 kilohms
- AD-MM/40 dB INPUT, 2.5 mV, 0.63 mV, 47 kilohms
- AD-MC/60 dB INPUT, 0.25 mV, 0.063 mV, 10/30/100/300 ohms, switchable
- AD-MC/70 dB INPUT, 0.08 mV, 0.02 mV, 10/30/100/300 ohms, switchable
- BALANCED/LINE, 252 mV, 63 mV, 40/20 kilohms, switchable
Signal-to-Noise Ratio
Input, Input shorted (A weighting) S/N ratio at rated output, EIA S/N
- AD-MM/30 dB INPUT, 94 dB, 86 dB
- AD-MM/40 dB INPUT, 85 dB, 86 dB
- AD-MC/60 dB INPUT, 80 dB, 86 dB
- AD-MC/70 dB INPUT, 73 dB, 87 dB
- BALANCED/LINE, 111 dB, 110 dB
