HiFiMAN EF5 headphone amp upgrade with Burson Discrete V4 opamp

Published on

Carlos G
October 31, 2014

Post Info

Feedbacks - V4 SS Opamp
HiFiMAN EF5

I installed your Supreme Sound opamps for Hifiman EF 5 – headphone amplifier. I replaced it for IC opamp OPA 627 BP. After burn the system (about 40 hours) to clear sound across the spectrum, significantly raised dynamics, and show musicians in space is much more accurate. I took your scaled Sound opamp 4th generation, so I placed it at the socets IC opamp. I had in a plastic housing EF 5 hole cut to them passed your opamp. Result you can see in my photos.

I think it looks interesting and unconventional. It’s the only way into the headphone amplifier to get you a great discrete amplifier.

Great combination. Thank you for a great product, I definitely recommend!

Ivan

The System

Listening with

HiFiMAN EF5 · Headphone amp: hybrid tube (12AU7) / opamp (OP275) headphone amp with external PSU · discontinued

Frequency response: 20 Hz – 30 kHz
Output impedance: 2 Ω (headphone, as listed)
Gain: high / low (switchable)
Inputs: 1x RCA
Input impedance: 50 kΩ
Outputs: 6.35 mm headphone
Other: output “up to 15 V at 32 Ω” (as published; no power figure); THD <0.2%; S/N >95 dB; DY-1 external supply

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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

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Also in the system

OPA627 · Operational amplifier

Supply voltage: ±4.5 V to ±18 V (recommended); ±18 V dual-supply absolute maximum
Gain-bandwidth product: 45 MHz typ (OPA627AU/BU, gain = 1, CL = 30 pF); 16 MHz typ (OPA627AM/BM/SM)
Dual or single: single
Package: SOIC-8; TO-99
Quiescent current: 7 mA typ / 7.5 mA max

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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.