I've been a fan of Musical Fidelity from its beginnings in the early 1980s. The British company's original 30-watt-per-channel stereo A1 integrated amplifier was a hit with budget-minded audiophiles back in the day, and it also offered seriously expensive gear.
Musical Fidelity started making headphone amplifiers long before the current headphones craze started. The model we're looking at today is Musical Fidelity's pure Class A M1 HPA headphone amp ($799).
The HPA has very low output impedance (below 1 ohm), so Musical Fidelity claims it can "drive" any headphones with ease. The circuit is a fully discrete Class A design, with no op-amps in the audio path, so it's built like a small high-end power amp. The HPA has two inputs--line and USB--and there's a variable output, so the HPA can be used as a stereo preamplifier in a hi-fi system. It has two 6.3mm headphone jacks on the front panel.
Some previous generations of Musical Fidelity's styling were a little over the top for my taste, but the M1 HPA is understated and very classy.
I was in the mood for David Bowie so I popped in his "Diamond Dogs" CD. I love this-period Bowie, and "Rebel, Rebel" never gets old. His stinging guitar leads cut through better on the M1 HPA than they did with my Burson Audio HA-160 amp ($699). The impact of bass and drums scored a bit better as well with the HPA.
I'm not claiming there are day-and-night differences between the two amps, but the HPA was more rock-and-roll with my Sennheiser HD 650 full-size headphones, and that was even more evident with my Grado RS-1 headphones and the HPA.
My Audeze LCD-2 headphones have higher resolution than the Sennheiser or Grado; so on Bob Marley's "Exodus" CD the sharp drum attacks and shaker percussion at the beginning of "One Love" were much clearer over the LCD-2 than they were with the other 'phones. My Ultimate Ears Reference Monitor in-ear headphones were even better in that regard, but I still preferred the overall sound with any of the full-size headphones.
I hooked up my Mac Mini to the HPA's USB input and played Apple Lossless files from iTunes. The sound was perfectly acceptable, but nowhere as transparent and clear as what I heard from my Oppo BDP-95 Blu-ray player hooked up to the HPA's analog connections. Oh, well, you can always add a better external digital-to-analog converter and use it with the HPA.
I loved the sound of the HPA and highly recommend it to anyone who's already invested in a set of high-end, full-size headphones, but you may have to spring for a better DAC if you don't already have one or a great-sounding CD player. Check the Tempo High Fidelity Web site to find a local dealer.
Musical Fidelity hasn't forgotten the budget-minded audiophiles, and offers the V-Can headphone amp for $199 (review to come).