Pioneer SX-2500 receiver

 

Auto-tuning , solid state AM/FM stereo receiver.

The AM/FM auto-tuning feature of this outstanding receiver is really convenient - one touch of the button sends the tuning needle on to the next station, where it will lock onto the signal with uncanny accuracy. It's a center-tuning system exclusive with Pioneer. Another convenient feature is the remote control unit for auto-tuning and volume control, operable up to 7 meters. With a tremendous 340 watts of power, the SX-2500 can drive any type of speaker system easily, even low-efficiency designs. The tuner employs 5 ICs and 2 crystal filters to ensure an excellent sensitivity of 1,6 µV, bringing in even weak or distant stations clearly. All in all the very advanced technology and finest quality parts of the SX-2500 make it Pioneer's top-of-the-line stereophonic receiver.

 

Convenient and precise Auto-Tuning servo-mechanism system

Just touch the button and the tuning needle will travel along the dial, lighting up and stopping precisely at the next station, with the help of a center-tuning meter and servomechanism, exactly where the signal is strongest. When the needle reaches the end of the dial scale, it will "turn around" automatically.

The biggest problem in auto-tuning systems has always been in centering the needle accurately. In conventional systems, the inertia of the needle motor carries it a bit beyond the exact spot, but in the SX-2500 Pioneer has solved the problem electronically with the servo-mechanism, and the needle is neither slightly to the right of left of the correct position - it's right on. The discriminator supplies a point "0", and the needle locks onto this "0" position precisely and almost instantaneously. This auto-tuning, center-tuning system is the only truly accurate one, and it's exclusive with Pioneer. When the needle moves inn the auto-tuning mode, the muting switch turns on automatically to cut out inter-station noise.

 

Specifications

Audio Section

Music Power Output

208 watts (IHF Rating) at 8 Ω

340 watts at 4 Ω

Continuous Power Output (Each channel driven)

84 W / 84 W at 8 Ω  (1 kHz, T.H.D. 0,5%)

120 W / 120 W at 4 Ω  (1 kHz, T.H.D. 0,5%)

Continuous Power Output (Both channel driven)

72 W / 72 W at 8 Ω  (1 kHz, T.H.D. 0,5%)

90 W / 90 W at 4 Ω  (1 kHz, T.H.D. 0,5%)

Total Harmonic Distortion :  less than 0,5% (at 1 kHz, Continuous Power Output)

Damping Factor:  40 (at 8 Ω , 1 kHz)

Frequency Response:  20 Hz to 70 kHz ±2 dB

Power Bandwidth:  8 Hz to 40 kHz (IHF rating)

Hum and Noise:

Phono Mag :  better than 80 dB

Aux :  better than 100 dB

Input Sensitivity/Impedance (at 1 kHz, continuous power)

Phono 1 (MC) :  110 µV/30 Ω  (with PP-402)

Phono Mag :  2,7 mV/50 k Ω

Phono Cer/Crystal :  60 mV/100 k Ω

Aux :  200 mV/100 k Ω

Tape Monitor :  200 mV/100 k Ω

Main Input :  500 mV/120 k Ω

Output Jacks and Terminals

Speakers (A, B) 4 - 16 ohms

Stereo Headphone Jack

Tape Recording jack

Tape Rec/Power Bandwidth Connector (DIN type)

Remote Control Connector (4 P)

MC Transformer Connector (* P)

Equalization Curves:  Phono RIAA

Controls

Bass :  +12 dB -9 dB at 100 Hz

Treble :  +9 dB -12 dB at 10 kHz

Filters Low :  Cut 8 dB at 50 Hz

Filters High :  Cut 10 dB at 20 kHz

Loudness Contour:  Switchable to On-Off +13 dB (at 50 Hz), +6 dB (at 10 kHz), with Volume control set at -40 dB

Semiconductors:  2 FETs; 36 Transistor; 18 Diodes; 2 Thermistors

FM Tuner Section

Frequency Range:  87,5 MHz to 108 MHz

IHF Sensitivity:  1,6 µV (at 98 MHz)

Capture Ratio:  1,0 dB  (at 98 MHz)

Selectivity:  65 dB  (at 98 MHz)

Image Rejection:  90 dB  (at 98 MHz)

Signal-to-Noise Ratio:  better than 70 dB (IHF rating)

Antenna Input:  300 Ω  balanced; 75 Ω  unbalanced

FM MPX Section

Channel Separation:  40 dB (at 1 kHz)

Total Harmonic Distortion :  0,5% (at 1 kHz)

AM Tuner Section

Frequency Range:  525 kHz to 1605 kHz

IHF Sensitivity:  8 µV

Image rejection:  83 dB (at 1,000 kHz)

Antenna Input:  Built-in ferrite loopstick antenna

Semiconductors:  5 ICs; 3 FETs; 34 Transistors; 35 Diodes

Miscellaneous

Power Requirements:  110, 120, 130, 220 240 V, 50/60 Hz

Power Consumption:  220 VA

Dimensions (W x H x D):  489 x 146 x 384 mm (19-1/8" x 5-3/4" x 15-1/8")

Weight (net):  15 kg (33 lb)