Aurex SY-C15/SY-C15K

Commentary

Compact design DC control amplifier.

It has a two block structure consisting of an equalizer and a tone (flat) amplifier. Both of them have a DC amplifier structure without NF (negative feedback) capacitors.

A newly developed dual FET (2SK146) is used in the first stage of the equalizer amplifier section. In addition, the circuit structure consists of two differential stages and all stages are directly connected OCL. The output stage is SEPP, and the output impedance is kept low to improve load stability.
For the RIAA element, a film capacitor, a styrene capacitor and a carbon resistor are selectively used, and the deviation is ± 0.2 dB.
The power supply is ± 2 power supply system with ± 32 v applied voltage and gain of approximately 34 db.

The tone amplifier section is a 2-stage and all-stage differential direct-coupled circuit using a dual FET at the first stage. The output is SEPP. As with the equalizer, the ± 2 power supply system ensures a wide dynamic range.
When the defeat switch is turned on, the tone element of the NF circuit becomes a cancel state and operates as a flat amplifier without losing gain.

Equipped with an equalizer direct switch, you can jump the tone amplifier completely and output the equalizer output as it is.
Since the gain of the tone amplifier is 17 dB, it can also be used as a muting switch by canceling this gain.

Equipped with an out-off switch, the volume can be reduced to 0.

Equipped with a function indicator with green LED, and the power ON indication is also used as a volume indicator.
The LED power supply is designed with a separate transformer winding so that it does not burden the basic circuit.

The cabinet has a three piece structure consisting of a front and top plate, a bottom and side plate, and a rear terminal plate. It is made of aluminum pulled out and is 5 mm thick on the front and 3 mm thick on the other parts.
The structure is such that the screws are not visible except for the bottom back surface.

Uses gold-plated terminal.

There are 2 color variations, SY-C15 of walkers or rollators for the elderly Lathe and SY-C15K of BlackCar Lathe.

Model Rating

Type	Control amplifier
Input Sensitivity / Impedance	Phono1/2 : 2.5mV/47k Ω Tuner, Aux, Tape : 150mV/47k Ω
Output Voltage / Impedance	Rec out : 150mV/150 Ω Output : 1.0V/150 Ω (approx. 17 dB down with EQ Direct)
Phono maximum allowable input	300 mv (RMS, 1 kHz)
RIAA deviation	20 Hz to 20 kHz ± 0.2 dB
Frequency Response (Aux)	10 Hz ~ 100 kHz + 0 -2dB
Harmonic distortion factor	0.01% (at 1 kHz, 1 V Output)
Signal-to-noise ratio (IHF-A network)	Phono:88dB Aux:106dB
Tone control	Bass : ± 10 dB (100 Hz) Treble : ± 10 dB (20 kHz)
Subsonic filter	10 Hz, 6dB/oct.
Semiconductor used	Transistor : 25 Diode : 8 pcs FET : 6 LED : 7
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	10W
External dimensions	Width 257x Height 54x Depth 208 mm
Weight	2.7kg