Description: DescriptionYAMAHA CA-1000II Stereo pre-main amplifier with Class-B-Class-A operation switchable main amplifier. The main amplifier uses an all-stage direct-coupled pure complementary OCL circuit that eliminates interstage capacitors. Furthermore, high stability is obtained by using two stages of differential amplifiers and a bias stabilization circuit with transistors, and FETs are used in the bias circuit of the first-stage differential amplifier to obtain ideal bias characteristics due to their constant-current characteristics. The power stage operation system is switched between Class-B and Class-A, allowing the user to freely select between the stable power of Class-B and the low distortion of Class-A. The power supply section uses a large core power transformer with excellent regulation, 18000μF x 2 capacitors, and a large-capacity rectifier diode with a surge current of 250A. In addition, a separately set constant voltage power supply is used to drive all stages except the power stage to improve the overall stability of the amplifier. The protection circuit has two built-in stages, one for power transistors and the other for speakers. The power transistor protection circuit is a quick-acting system that immediately responds to an overload on the order of μS. If the load drops below 2 ohms or the output terminals are shorted, the protection circuit instantly makes a differential movement to prevent trouble. Since this circuit is an input limiter type, playback is not interrupted even when the protection circuit is activated, only the output power is reduced. The speaker protection circuit is based on Yamaha's original circuit system. If the DC voltage at the output terminal exceeds ±2V, the relay instantly makes a differential motion to shut down the signal path to the speaker. The relay automatically recovers when the voltage falls within ±2V, and since it also serves as a power muting device, there is no shock noise caused by rush currents when the power switch is turned on. The first stage of the equalizer amplifier uses FETs in the SRPP method, which greatly improves the secondary distortion compared to the single method, since FETs have the advantage that the pulse noise is much lower than that of transistors and the noise figure decreases as the signal source impedance increases. In addition, the high supply voltage of +50V and the SEPP output stage, which allows for low output impedance, provide high output power with low distortion and a generous dynamic margin. For the equalizer element, a combination of metal film resistors (±1% error) and styrene capacitors (±1% and ±2% error) are used, and a tantalum capacitor is used to minimize leakage current and ageing. The Phono 1 circuit is equipped with an input impedance switching switch, allowing the load impedance of the cartridge to be adjusted to the optimum value. It also has a built-in head amp for MC cartridges, allowing direct connection of MC cartridges without a step-up transformer. The function switch is mounted on the equalizer board, and external noise countermeasures are taken by means of wiring and a shielded case to achieve higher sound quality. The tone control circuit uses the Yamaha method of mixing NF and CR types with a 3-stage direct-coupled amplifier. Careful selection of low-noise transistors reduces residual noise and achieves high signal-to-noise ratio and low distortion. In the Tone Defeat position, the circuit operates as a flat amplifier. The filter circuit consists of a 3-stage direct-coupled amplifier with emphasis on phase characteristics and distortion rate. The cutoff frequency of both the low and high filters can be switched in two steps. The loudness circuit employs a continuously variable continuous loudness control with a dedicated loudness volume to allow adjustment based on the actual listener's ear. It is equipped with a pre-main coupler that allows the preamplifier and main amplifier to be used separately from each other. Audio muting is provided. An amplifier dedicated to microphones is provided to prevent deterioration of sound quality due to time constant switching of the equalizer. All my products are 100% Authentic.Please feel free to contact us if you have any question. Shipping We ship using FedEx, DHL and Japan Post. PaymentWe usually ship within 5〜10 business days of receiving cleared payment. 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. I do not mark merchandise values below value or mark items as "gifts" - US and International government regulations prohibit such behavior.
Price: 560 USD
Location: gunma
End Time: 2024-08-21T05:08:08.000Z
Shipping Cost: 0 USD
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Return shipping will be paid by: Seller
All returns accepted: Returns Accepted
Item must be returned within: 60 Days
Refund will be given as: Money Back
Return policy details:
Brand: Yamaha
Type: Integrated Amplifier
Model: Yamaha CA-1000II
Color: Black
Damping Factor: 50 or more (8Ω, 1kHz)
Supply voltage: AC100V、50Hz/60Hz
Circuit method: Class-B/A switchable all-stage direct-coupled SEPP OCL circuit
Dynamic power (IHF): 200W (Class B)
Effective output 1kHz: 15W+15W (8Ω, Class-A operation),100W+100W (4Ω, Class-B operation)
Effective output 1kHz in single-channel operation: 15W/15W (8Ω, Class-A operation),100W/100W (4Ω, Class-B operation)
Input Sensitivity/Impedance: Class-A operation: 330mV/40kΩ, Class-B operation: 775mV/40kΩ
Output terminal Speaker terminals: 3 channels
Output terminal Headphone jack: 4Ω～16Ω
SN ratio (IHF, A-network): 100dB
Residual noise: 0.8mV (pre + main amp, 8 ohm)
Circuit method Equalizer amplifier: FET SRPP input, Tr SEPP output 6-jewel amplifier
Circuit method Control amplifier: Intermediate emitter follower type 3
Input sensitivity/impedance Phono1 MC: MC:200μV/100Ω, 3mV/50kΩ、100kΩ
Phono maximum allowable input (1kHz): 310mVrms(870mVp-p)
Frequency Response Phono(RIAA deviation): 30Hz～15kHz ±0.2dB
Frequency Response Tuner,AUX,Tape PB: 10Hz～50kHz +0.5 -1dB
SN Ratio Phono1 MC: 70dB
Tone Control Bass: ±15dB(50Hz), turnover frequency: 250Hz, 500Hz
Tone Control Treble: ±10dB(10kHz), turnover frequency: 2.5kHz, 5kHz
Filter Low: 20Hz/70Hz、12dB/oct
Filter High: 6kHz/12kHz、6dB/oct
Loudness Control: Continuous loudness
Audio muting: -20dB
Power consumption: 195W
Dynamic power (0.05% distortion): 85W(8Ω、1kHz)
Power Bandwidth: 10Hz～50kHz(IHF、0.05%THD)
Load impedance: 4Ω～16Ω
Phono maximum allowable input: 150mVrms(1kHz、0.05%THD)
Tone control: Bass:±10dB(50Hz) Treble:±9dB(10kHz)
Loudness (Vol-30dB): +9dB(50Hz)、+6.5dB(10kHz)
Rated power consumption: 80W
Effective power:20Hz to 20kHz: 15W+15W (8Ω, Class-A operation),85W+85W (4Ω, Class-B operation)
Total Harmonic Distortion Class A: 0.1% or less(at RMS output), 0.02% or less(at 1W output)
Total Harmonic Distortion Class B: 0.1% or less (at RMS output), 0.04% or less (at 1W output)
Power bandwidth Class-A: 5Hz～100kHz
Power bandwidth Class B: 5Hz～50kHz
External dimensions: Width 436 x Height 144 x Depth 323mm
Weight: 15.5kg
