PecanPi®+ Implementation, Spec, & Test Results
Implementation
DAC Chips
Asahi Kasei Microdevices (AKM) flagship AK4499EXEQ combined with AK4191EQ
Clocking
Crystek CCHD-575 oscillator — ultra-low clock jitter of 82fSec
S/PDIF Receiver
Cirrus Logic CS8416
Output stage
True balanced fully differential output stages, using OPA1612s, low-noise Panasonic resistors, and proprietary filtering topology
Ultra-low Noise Linear Power Supplies
- LT3045 (0.8uV noise) for positive op-amp power supply
- LT3090 (18uV noise) for negative op-amp power supply
- LT3042 (0.8uV noise) for DAC Chips
Headphone Driver
- Dual parallel OPA1622s for regular headphones
- Quad parallel OPA1622s for balanced headphones
Specifications
XLR Output (including headphone driver):
- Signal-to-Noise Ratio (SNR): 133dB (A-weighted)
- Residual Noise: 1.174uV (A-weighted)
- Dynamic Range (DNR): 129dB
- Total Harmonic Distortion + Noise (THD+N) @ 0dBFS: -116dB or 0.00016%
- Total Harmonic Distortion + Noise (THD+N) @ -6dBFS: -119dB or 0.00011%
- Frequency Response: DC (0Hz) to 22kHz @ 48kHz sample rate
- Frequency Response: DC (0Hz) to 44kHz @ 96kHz sample rate
- Frequency Response: DC (0Hz) to 88kHz @ 192kHz sample rate
- Output Voltage: 5.22Vrms (+16.6dBu)
RCA Output (including headphone driver):
- Signal-to-Noise Ratio (SNR): 128dB (A-weighted)
- Residual Noise: 1.308uV (A-weighted)
- Dynamic Range (DNR): 124dB
- Total Harmonic Distortion + Noise (THD+N) @ 0dBFS: -112dB or 0.00025%
- Total Harmonic Distortion + Noise (THD+N) @ -6dBFS: -116dB or 0.00016%
- Frequency Response: DC (0Hz) to 22kHz @ 48kHz sample rate
- Frequency Response: DC (0Hz) to 44kHz @ 96kHz sample rate
- Frequency Response: DC (0Hz) to 88kHz @ 192kHz sample rate
- Output Voltage: 2.61Vrms (+10.6dBu)
Regular Headphone Output:
- Power into 16Ω: 851mW peak
- Power into 32Ω: 425mW peak
- Power into 150Ω: 91mW peak
- Power into 300Ω: 45.5mW peak
- Output Impedance: < 550mΩ
Balanced Headphone Output:
- Power into 32Ω: 1.7W peak
- Power into 150Ω: 363mW peak
- Power into 600Ω: 90mW peak
- Output Impedance: < 60mΩ
Input Power:
- Input Connector: Barrel Plug, 2.1mm I.D. x 5.5mm O.D. x 9.5mm
- Input Voltage: 9VDC
- Input Power: 20W Max (w/ Raspberry Pi)
Size:
- Streamer / Ultra: 195 x 120 x 100mm (7.7 x 4.75 x 4.25in)
- DAC: 97mm (3.82”) x 78.5mm (3.09”) x 38.1 mm (1.5”)
General
- Sampling Rates: 44.1, 48, 88.2, 96, 176.4, 192, 352.8, and 384kHz (S/PDIF limited to 192k)
- Bit Rates: 16, 24 and 32-bits (S/PDIF limited to 24-bits)
- Formats: Supports all formats. DSD is converter to PCM before playback.
- DAC Compatible Rpi Models: 1B+, 1A+, 2B, 3B, 3B+, 4B, 5, Zero, & ZeroW
- DAC Compatible Asus Models: Tinker Board & Tinker Board S
- S/PDIF Input: Compatible with all sampling and bit rates listed above
Test Results