COUNTERPOINT DA-10st/DA-10UA

Commentary

A D/A converter that supports a variety of conversion methods, incorporating the concept unique to Counterpoint for digital reproduction.

The D/A conversion section of the DA-10st is equipped with a 20-bit resolution DAC chip manufactured by Analog Devices, and the DA-10UA is equipped with a dual 20-bit DAC manufactured by Ultra Analog.
Since no operational amplifier is used inside the chip, there is no need for negative feedback, which is harmful to sound, and more natural reproducibility is obtained.

The digital audio interface uses the latest CS8412 receiver chip from Crystal Semiconductor, which has a reputation for reliability. This reduces the jitter component, which affects the accuracy of the digital section, to 1/4 of the conventional one.

The front panel of the DA-10 series is equipped with a DAC trim that can adjust the linearity at the minute level to optimize the linearity at the minute level.
The DA-10UA does not require adjustment of this trimmer, but when the optional DAC card DA10-AD20 is used, the LED lights up and adjustment is possible.

The analog stage and current / voltage conversion stage are fully discrete 0 feedback amplifiers to eliminate signal degradation that was unavoidable in voltage / current conversion with conventional 100% feedback type operational amplifiers.

Counter Point's original power transformer is used to separate digital and analog sections. In addition, 17 decoupling power supplies are used to eliminate interference from the digital section to the analog section.

The low-pass filter uses a passive 3rd-order LC Bessel type antialiasing filter to reduce overshoot, ringing, and group delay, which are common in high-order steep filters.

It uses carefully selected parts such as Lauderstein metal film resistor and TRT film condenser.

A total of four digital input systems are installed : a co-axial Route 3 and one optical system. The co-axial is a gold-plated BNC type and the optical system is an ST-link type.
In addition, two types of interfaces, Coaxial and TOSLINK, are installed as tape input / output for connecting the DAT deck.

The DA-10 series is designed so that the DAC card board can be replaced to enjoy the difference of the digital conversion method.
The DAC card was sold as a separately sold option.

Model Rating

Type	D/A converter
Method	20-bit 8 x oversampling
Sampling frequency	32 khz, 44.1 khz, 48 khz
Digital source input	Coaxial (BNC Type) : Route 3 Optical (ST link) : 1 system
Digital tape input / output	Input : Coaxial (BNC Type) : 1 System Optical (TOSLINK) : 1 system Output : Co-axial (BNC type) : 1 system Optical (TOSLINK) : 1 system
Jittering	50 pS or Less (Using Crystal Semiconductor CS8412)
Digital filter	Bar Brown 8 x oversampling digital filter
Post filter	Third order passive LC Bessel filter
Analog output	RCA Type
Frequency characteristic	20 Hz ~ 20 kHz + 0 -3dB at 44.1 kHz Sampling
THD	0.009% or Less (20 Hz to 20 kHz)
Output level	2.1Vrms
Output impedance	120 Ω
Maximum external dimensions	DA-10st : Width 483x Height 65x Depth 313 mm DA-10UA : Width 483x Height 65x Depth 315 mm
Weight	DA-10st:5.5kg DA-10UA:6kg
Sold Separately	Crystal Semiconductor Corporation DA10-CS18 18-bit delta / sigma DAC (¥ 58000) Analog Devices Corporation DA10-AD20 20-bit DAC (¥ 49000) Ultra Analog Company DA10-UA20 Dual 20-bit DAC (¥ 138000)