ARCAM DELTA110
¥ 275,000 (around 1991)
Commentary
Built-in DAC preamplifier with digital input.
The D/A converter uses a full differential mode bit stream method.
The D/A converter uses two Philips SAA7321 bit stream DACs for each channel and operates in differential mode.
The Arkham custom IC is used for the digital signal processing before it is input to the converter and is specially shaped to eliminate the nonlinearity of the D/A converter almost completely and to increase the signal-to-noise ratio.
The custom IC greatly reduces digital noise generation by replacing all conventional ICs with the custom IC, and the noise level is reduced by applying special noise countermeasures only found in military electronics.
The D/A converter circuit is automatically turned off when an analog input is used.
The D/A converter circuit was built on a plug-in type single board and was designed to be replaced and upgraded when the converter circuit was improved.
It is equipped with an absolute phase switch.
Some CDs reproduced from an old analog record are inverted in phase. This type of CD is also supported by inverting the phase using the absolute phase switch.
Phase inversion is processed digitally by Arkham's custom IC.
Signal switching is performed by a contact-sealed relay located immediately behind the input / output terminals, which shortens the signal path as much as possible and reduces noise and distortion.
In addition, the contact-sealed relay has less corrosion over time than the conventional open switch, and enables high-purity transmission.
Equipped with feedback loop balance control.
This simplifies the signal path and reduces noise and distortion.
The power supply circuit is equipped with dedicated toroidal power transformers for digital and analog circuits respectively.
In addition, 12 separate stabilized power supply circuits are installed to provide a stable voltage supply to each circuit and to suppress noise as much as possible.
In the DELTA110, only the input selector switch performs both functions, whereas in conventional preamplifiers, the playback selector and the recording selector were provided separately.
When the green LED above the input switch lights up, the playback source (Listen) can be switched, and when the red LED lights up, the recording source (Record) can be switched.
This simplifies internal wiring and switches.
Wireless remote control is included.
Model Rating
| Type | Control amplifier |
| Analog input | Disc MM : 2mV/47k Ω Disc MC : 100 μ V/220 Ω AV, Tuner, Tape1/2 : 200mV/45k Ω |
| Digital input | Coaxial : 1 system Optical : 1 system |
| D/A converter | 1 bit x256 times |
| Sampling frequency | 44.1 kHz, 48 kHz |
| Number of D/A converters | 4 |
| Frequency characteristic | Disc : 50 hz to 20 khz + 0. 2-0. 5 db Other : 20 Hz to 20 kHz + 0. 1-0. 5 dB |
| NOISE | Disc MM:-64dB(CCIR) Disc MC:-50dB(CCIR) Line:-89dB(CCIR) Digital:-96dB(CCIR) |
| Distortion | 0.01% or Less (1 V Output) |
| Output Level / Impedance | Main : 2V/25 Ω, max> 8 V Tape1/2 : 300mV/70 Ω |
| Pwer | 100 VAC, 50Hz/60Hz |
| External dimensions | Width 430x Height 64x Depth 270 mm |
| Weight | 3.7kg |
| Attachment | Wireless Remote Control |