Sq.Ver.02-B Headphone Amplifier (discontinued production)



Features

  • Very compact and small enough to fit in your hand (W:2.4" x H:1" x L:2.3" without volume knob)
  • Special printed circuit board with copper weight 70um (Standard PCB copper weight is 35um)
  • Product driving-time is around 17hours/charge (for reference only)
    • (It was measured actually by HiFiman HE-6. Of course, it is varied depending on your headphones and/or earphones)
  • Equipped with charge-circuit for Ni-MH or Ni-Cd AAA size rechargeable batteries
  • Able to drive 16-300ohm headphones or earphones
  • Able to easily drive 30-150ohm headphones or earphones with excellent performance
  • General performance is enough to drive headphones or earphones

Package included

  • Sq.Ver.02-B headphone amplifier x1
  • Ni-MH 1.2V 900mAh rechargeable batteries x2
  • USB charge cable x1

Pictures

 

 


Audio analyzer test results

          Fig.1 Measurement environment
  • Measurement environment (fig.1)
    • Agilent(HP) 8903B audio analyzer x2 (for true 2ch. test)
      • THD+N, Frequency response and Crosstalk test
      • THD+N test is carried out with 80kHz LPF
    • TEXIO VA-2230A audio analyzer x1
      • S/N and Dynamic range test
      • S/N and Dynamic range test are carried out with A-Weighting filter and 80kHz LPF
  • Results
    • Summary
      • THD+N (1kHz Sine with 80kHz LPF)
        • Rch=0.006% and Lch=0.007% when output power is 12mW into 30ohm load
        • Rch=0.005% and Lch=0.006% when output power is 7mW into 63ohm load
        • Rch=0.004% and Lch=0.006% when output power is 4mW into 100ohm load
        • Rch=0.005% and Lch=0.005% when output power is 3mW into 150ohm load
      • Frequency response (20Hz-20kHz Sine)
        • Rch=+0.18, -0.86dB and Lch=+0.16, -0.86dB into 30ohm load
        • Rch=+0.24, -0.28dB and Lch=+0.23, -0.27dB into 63ohm load
        • Rch=+0.25, -0.16dB and Lch=+0.25, -0.14dB into 100ohm load
        • Rch=+0.13, -0.13dB and Lch=+0.14, -0.13dB into 150ohm load
      • Crosstalk (20Hz-20kHz Sine)
        • Rch=-64 and Lch=-67dB into 30ohm load at 1kHz
        • Rch=-71 and Lch=-73dB into 63ohm load at 1kHz
        • Rch=-71 and Lch=-74dB into 100ohm load at 1kHz
        • Rch=-76 and Lch=-74dB into 150ohm load at 1kHz
      • S/N and Dynamic range(1kHz Sine with A-Weighting filter and 80kHz LPF)
        • Rch=99.4dB and Lch=99.2dB into 30ohm load
        • Rch=100.2dB and Lch=100.1dB into 63ohm load
        • Rch=100.5dB and Lch=100.3dB into 100ohm load
        • Rch=100.9dB and Lch=100.8dB into 150ohm load
    • Extensive results
      • THD+N vs Output power results are shown in fig.2-5
        • (1kHz Sine with 80kHz LPF)
      • Relative response vs Frequency results are shown in fig.6-9
        • (20Hz-20kHz Sine)
      • Crosstalk vs Frequency results are shown in fig.10-13
        • (20Hz-20kHz Sine)

 
    Fig.2 THD+N vs Output power into 30ohm load        Fig.3 THD+N vs Output power into 63ohm load

 
   Fig.4 THD+N vs Output power into 100ohm load       Fig.5 THD+N vs Output power into 150ohm load

 
   Fig.6 Response vs Frequency into 30ohm load        Fig.7 Response vs Frequency into 63ohm load 

 
   Fig.8 Response vs Frequency into 100ohm load       Fig.9 Response vs Frequency into 150ohm load

 
  Fig.10 Crosstalk vs Frequency into 30ohm load       Fig.11 Crosstalk vs Frequency into 63ohm load

 
  Fig.12 Crosstalk vs Frequency into 100ohm load     Fig.13 Crosstalk vs Frequency into 150ohm load


RMAA test results

  • Measurement environment
    • Creative E-MU 0204 by ASIO with RMAA 6.2.3 PRO x1
    • All tests were carried out "without 20Hz-20kHz filter" at RMAA configuration
  • Results
    • Summary
      • See fig.14
    • Extensive results
      • Frequency response is shown in fig.15
      • Noise level is shown in fig.16
      • Dynamic range is shown in fig.17
      • THD+N is shown in fig.18
      • IMD+N is shown in fig.19
      • Stereo crosstalk is shown in fig.20

                            Fig.14 RMAA test summary


 
   Fig.15 Frequency response results with RMAA            Fig.16 Noise level results with RMAA

 
     Fig.17 Dynamic range results with RMAA                  Fig.18 THD+N results with RMAA

 
         Fig.19 IMD+N results with RMAA                     Fig.20 Crosstalk results with RMAA


Waveform results

  • Measurement environment
    • TEXIO FG-274 DDS Function Generator x1
    • TEXIO DCS-9515YHK Digital Oscilloscope x1
  • Results
    • Sine waves into 30ohm load at 100Hz, 1kHz, 10kHz, 20kHz, 50kHz and 100kHz
      • See fig.21-26
      • The top trace is original source
    • Triangle waves into 30ohm load at 100Hz, 1kHz, 10kHz, 20kHz, 50kHz and 100kHz
      • See fig.27-32
      • The top trace is original source
    • Square waves into 30ohm load at 100Hz, 1kHz, 10kHz, 20kHz, 50kHz and 100kHz
      • See fig.33-38
      • Clipped square waveform is shown in fig.39, 40
      • The top trace is original source

 
    Fig.21 Sine wave into 30ohm load at 100Hz           Fig.22 Sine wave into 30ohm load at 1kHz

 
   Fig.23 Sine wave into 30ohm load at 10kHz            Fig.24 Sine wave into 30ohm load at 20kHz

 
   Fig.25 Sine wave into 30ohm load at 50kHz           Fig.26 Sine wave into 30ohm load at 100kHz

 
   Fig.27 Triangle wave into 30ohm load at 100Hz      Fig.28 Triangle wave into 30ohm load at 1kHz

 
   Fig.29 Triangle wave into 30ohm load at 10kHz      Fig.30 Triangle wave into 30ohm load at 20kHz


 
   Fig.31 Triangle wave into 30ohm load at 50kHz     Fig.32 Triangle wave into 30ohm load at 100kHz

 
   Fig.33 Square wave into 30ohm load at 100Hz         Fig.34 Square wave into 30ohm load at 1kHz

 
   Fig.35 Square wave into 30ohm load at 10kHz         Fig.36 Square wave into 30ohm load at 20kHz

 
   Fig.37 Square wave into 30ohm load at 50kHz         Fig.38 Square wave into 30ohm load at 100kHz

 
 Fig.39 Clipped sq. wave into 30ohm load at 50kHz   Fig.40 Clipped sq. wave into 30ohm load at 100kHz









Copyright(c) 2012-2019 Shintaro Shinozaki, Ph.D. All rights reserved.