Aggiungo dei dettagli tecnici ufficiali del Firebird :
Fire Bird DAC Detail Spec
Writer: Bann Audio Co., LTD
Verify: Ernest Cho
1) Real 24bit R2R Ladder DAC technology
There is no 24bit R2R ladder DAC chip produced in the traditional way. To get 24bit resolution, we use two 16bit R2R ladder DAC chips. Each chip handles higher 16bit and lower 8bit. To match up two chips precisely, tune with high-precision variable resistors and Audio Precision System 2722 analyzer. It takes about two hours to adjust matching and MSB setting.
R2R ladder DAC chips are not identical in performance, cause of laser trimming precision limitation. So, we carefully select DAC chips for perfection with custom test equipment before production. Only 25~30% selected DAC chips are used, others are all discard.
Fire Bird DAC can handle max 192kHz sampling rate audio signal input. All input audio signals are oversampled to improvement sound quality. CD quality 44.1kHz & DAT 48kHz audio signal oversample rates are x16 with custom tuned DSP algorithm by SPARTAN FPGA. When 44.1kHz & 48kHz audio signals are oversampled, linear phase and minimum phase oversampling filter algorithms are mixed use step by step. We carefully tested various oversampling algorithm combination for a long time. As a result, this unique algorithm is better than only one linear or minimum phase oversampling filter used. We call this, multiple stage mixed oversampling algorithm.
3) Master Clock
Two master clock oscillator included for asynchronous USB operation. These clock oscillators’ stability are under 10PPM (maximum 10PPM; consider with any variables like aging drift, temperature changes and vibration). Specially, it’s not performance degraded by vibration. It was designed to use for missile and intelligent bomb.
Calculated clock oscillators’ jitter values are as below;
22.5792MHz, 885 femto sec max jitter
24.5760MHz, 814 femto sec max jitter
4) Power Supply
For better sound quality, digital and analog power supplies are separated. Low noise and low leakage inductance R-Core Transformers are used. For stable power supply, each power channel has low ESR 10,000uF condenser buffer and fast rising time rectifiers are used.
DAC Chip: Manually Selected Analog Device AD1851RZ (J grade) x 4
DSP: Xilinx Spartan FPGA with x16 oversampling, Linear & Minimum Phase Oversampling, Apodising Filter * Custom Filter Design
Data rate: Up to 24bit/192kHz
Digital Input: USB Audio Spec 2.0 (Asynchronous) x 1, Optical Toslink x 1, SPDIF Coax (RCA) x 1, AES/EBU XLR x 1
Analog Output: Un-Balanced RCA, Balanced XLR
Power Supply: R-Core Transformer Linear Power Supply,
Analog와 Digital 전원 분리
Dynamic Range: 120dB*
Output Voltage: RCA 2.2V, XLR 4.4V
Dimension(WDH): 436x305x54mm(with Foot 63.5)
Case Material: 100% Aluminum Alloy
Power consumption: Under 10W
*note: Dynamic range value is measured by Audio Precision System 2722 analyzer