Audiotrak ImAmp mod discrete opamp

Albert’s Burson V4 Opamp with Audiotrak ImAmp

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Post Info

Before the upgrade, in my opinion the Imamp was not exciting. It was ok/decent, but after the upgrade, it’s really exciting and some music detail that I never noticed before now is noticable.

Btw, my source of music is Asus Xonar Essence STX (set to 24-bit, 44.1KHz). I’m using QED cable (50 cm) to hook the Xonar to Imamp, I don’t remember which QED model (the purple one as you can see on the Imamp03.jpg), it’s an old model I think since I bought it several years ago.

For the software player, I’m using foobar2000. And the headphone that I’m using is Beyerdynamic DT 770 Pro 250 ohm. I listen mainly to instrumental music of any kind: Soundtrack, jazz, classical, etc. Some pop music also.

And finally, now I have to find/build custom chassis for my Imamp since after the upgrade I can’t close it anymore. :D

Albert T.

The System

Listening with

Audiotrak ImAmp

Burson

Burson V4 Opamp · Discrete opamp (single / dual) · discontinued
  • Supply voltage: ±5 V to ±20 V (absolute maximum)
  • Gain-bandwidth product: 50 MHz (at 100 kHz)
  • Dual or single: dual and single
  • Package: dual 40 mm × 16 mm × 20 mm; single 40 mm × 16 mm × 14 mm; 8-pin

[1] [2]

Also in the system

ASUS Xonar Essence STX · Sound card: PCIe sound card with headphone amp · discontinued
  • Frequency response: 10 Hz – 90 kHz (-3 dB, 16-bit/44.1 kHz input)
  • Output impedance: not published
  • Output voltage: RCA 2 Vrms (line out, RCA/3.5)
  • Gain: not published
  • Inputs: 1x 6.3 mm line/mic in; aux (4-pin header)
  • Outputs: 1x 6.3 mm headphone; 2x RCA; S/PDIF out (optical/coax combo)
  • DAC / chipset: TI Burr-Brown PCM1792A; ASUS AV100 processor (192 kHz/24-bit)
  • Other: SNR (A) 124 dB front-out / 117 dB headphone-out; THD+N 1 kHz 0.0003% (front) / 0.001% (headphone); headphone voltage not published

[3]

beyerdynamic DT 770 PRO 250 Ohm · Headphones: closed-back, dynamic, circumaural
  • Impedance: 80 Ω (page default; 32 and 250 Ω versions sold)
  • Sensitivity: 96 dB SPL (reference not stated on page)
  • Frequency response: 5 Hz – 35 kHz
  • Plugs / cables supplied: straight cable with 3.5 mm plug and 6.35 mm adapter (current version)

[4]

Specs from manufacturer data unless a source below says otherwise. “calc.” values are worked out from those figures (V = √(P × R); 110 dB SPL used as a loud reference level). Gear listed without specs is not in our spec library yet.

  1. Burson V4 Opamp datasheet V1.1
  2. Burson V4 Opamp product page (archived 2015)
  3. ASUS Xonar Essence STX: archived page (web.archive.org)
  4. beyerdynamic DT 770 PRO 250 Ohm: north-america.beyerdynamic.com