Product Features Preamplifier using Yamaha original super low noise FET.
The basic circuit configuration is simple: equalizer amplifier, tone control amplifier and head amplifier for MC cartridge. In order to pursue the performance as a preamplifier, the accessory circuit is minimized to obtain excellent characteristics.
The equalizer circuit uses Yamaha's original super low noise pair FET, and consists of a cascode bootstrap current mirror differential input, Darlington connection constant current load emitter ground amplification, and a pure complementary parallel push-pull class A output stage.
The super low noise FET used in the first step dynamic amplification was newly developed for the C -2, and has very low noise and uniform electrical characteristics. This differential amplifier stage operates at a constant current bias with a current mirror cascode bootstrap, eliminates the DC cut capacitor at the input, and suppresses noise and degradation of low frequency stability.
In the second stage circuit, the load of the first stage is reduced by the constant current load emitter grounding of the Darlington connection, and sufficient gain is obtained.
The output stage is a pure complementary class A parallel push-pull circuit with a high high-frequency critical frequency (ft ≒ 100 MHz) and 2 sets of transistors with excellent complementary characteristics. It achieves a high output voltage at a low distortion rate while reducing the output impedance (600 Ω) and improving the depth stability.
The equalizer circuit uses a high-grade styrol capacitor and a metal film resistor for the RIAA element, and has a high accuracy of ± 0.2 dB or less.
The equalizer amplifier circuit is double-shielded.
The circuit configuration of the tone control unit amplifier is almost the same as that of the equalizer amplifier, with an NF tone control circuit. Both Bass and Treble use high-precision attenuators with 20 steps and 21 positions. In the 0 position, the elements with the time constant are completely separated from the circuit and the tone amplifier becomes a flat buffer amplifier.
A volume is inserted before the tone amplifier, but when this volume is reduced, the signal source impedance viewed from the tone amplifier changes. Like the equalizer amplifier, the C -2 tone amplifier uses a cascode bootstrap circuit in the first stage so that even if the volume is reduced during actual use, the distortion rate does not deteriorate. The output impedance is as low as 400 Ω due to the output stage of the complementary class A parallel push-pull, and together with the high power supply voltage, a maximum output of 775 V (0 dBm) against the rated 10 mV (10 kΩ load) can be obtained, even under load conditions of 600 Ω.
Yamaha's original super low noise IC is used for the head amplifier to achieve an SN ratio of 70 dB or more.
Equipped with a subsonic filter, it can cut unnecessary signals in the ultra-low range due to warpage of records, etc.
The volume uses a high-precision special four-row volume with two rows per channel. 2 sets of this volume are input and output of the tone amplifier. The level is adjusted from - ∞ to -20 dB on the output side of the amplifier, and from -20 dB to 0 dB on the input side of the amplifier. The residual noise is completely reduced to zero when the volume is completely reduced by this method.
The muting circuit by relay is inserted not only in Pre out but also in Rec out.
As a result, the output impedance is low and there is no characteristic degradation even when various related devices are connected. Specifications Type control amplifier Input sensitivity/impedance Phono 1/2: 2 mV/47 kΩ Phono3 (MC): 50 μV/10 kΩ Tuner, aux: 120 mV/47 kΩ Tape PB A/B: 120 mV/47 kΩ maximum permissible input Phono 1/2: Phono3: 30 mV (20 Hz) 300 mV (1 kHz) 3000 mV (20 kHz) 1.25 mV (20 Hz) 7.5 mV (1 kHz) 20 mV (20 kHz) Output Level/Impedance Pre out 1/2: 775 mV/400 Ω Rec out 1/2: 120 mV/660 Ω Frequency response Phono 1/2/3 (RIAA deviation): 30 Hz to 15 kHz ± 0.2 dB Tuner, aux: 5 Hz to 100 kHz + 0 -1.5 dB Tape A/B: 5 Hz to 100 kHz + 0 -1.5 dB Signal to noise ratio (IHF-A network) Phono 1/2: Phono3: Tuner, aux: 85 dB (2 mV Rated Input, Input Short) 99 dB (Input short at 10 mV input) 70 dB (At 50 μV Rated Input, Input 50 Ω Short) 100 dB (input short) Residual noise - ∞ dB strain rate Phono 1/2: Phono3 (MC): Tuner, Aux, Tape A/B: 0.003% or less (VRmax, 7.75 V output) 0.003% or Less (VR -30 dB, 775 mV output) 0.02% or Less (VRmax, 7.75 V output) 0.05% or Less (VR -30 dB, 775 mV output) 0.003% or Less (VRmax, 7.75 V output) 0.003% or Less (VR -30 dB, 775 mV output) tone control cutoff frequency Bass: 350 Hz Treble: 3.5 kHz Change (Bass: 20 Hz, Treble: 20 kHz) 0, ± 1.5, ± 1.5, ± 2.0, ± 3.0, ± 4.0, ± 5.0, ± 6.0, ± 8.0, ± 10 dB Subsonic Filter 15 Hz, 12 dB/oct Muting -20 dB, off Semiconductor ICs used: 2 FET module: 4 FET: 2 Transistors: 61 Zener diodes: 7 Diodes: 23 Power source 100 VAC, 50 Hz/60 Hz Power consumption 25 W External Dimensions Width 435 x Height 72 x Depth 320 mm Weight 7.8 kg Payment We only accept PayPal payments. Please pay within 5 days after bidding. Shipping Free Shipping Terms of Sale Money back guarantee within 30 days if returned by customer. International Buyers - Please Note: Import duties, taxes and charges are not included in the item price or shipping charges. These charges are the buyer's responsibility. Please check with your country's customs office to determine what these additional costs will be prior to bidding/buying. These charges are normally collected by the delivering freight (shipping) company or when you pick the item up - do not confuse them for additional shipping charges. |