A Headphone Amp for the Purists

The VA-221-SI is the fourth generation of Vectis Amplification's headphone amp. The topology utilises the incredible Burr-Brown OPA2134 amplifier. Some of the notable features are:
- Battery or wall power
- Buffered output
- 1/4" and 1/8" output jacks
- RCA, 1/4" or 1/8" input jack
- Switchable signal attenuation of -6 dB
- Switchable gain of 10 or 20 dB
- Stereo or Mono switch
- Switchable sound-stage option
- Small footprint in a classic look
The VA-221-SI is a single input device with three choices of input. The priority is 1/8" TRS > 1/4" TRS > RCA. Only a single input should be active during use.
The sound-stage is designed to reduce listener fatigue by bleeding a small portion of the signal across channels.
Because all sources have different output levels, the VA-221-SI is designed with a signal attenuation switch which is useful to attenuate the input signal when high output devices are used. A typical 0.3 VRMS signal will not require any attenuation but a professional output level of 1 VRMS will benefit from the 6 dB cut at the input.
The amplifier works well with a range of headphone impedances. I currently use it with Sennheiser HD 280 PRO headphones at 64 Ohms and beyerdynamic DT 990 Pro at 250 Ohms. The sound is slightly reduced with the higher impedance headphones, but still more than loud enough to hurt.



