The main reason that I’m writing this article is to provide some thoughts about how the Beta22 actually sounds, as articles outlining the Beta22’s sound character is fairly rare.
If there is one thing that the Beta22 is famous for, it’s the power reserve. The Beta22 is able to output 18Wrms into 8Ω unbalanced, and up to 50Wrms into 8Ω balanced. The power output is said to be 9 times the output of the M³ amplifier. This sort of power output makes the Beta22 capable of driving efficient speakers, and the power reserve is overkill for most headphones. Voltage swing can be as high as 40Vp-p, and is capable of driving the AKG K1000 to very high levels.
So, what does all that power translate to? The Beta22 never feels underpowered, and is able to sufficiently drive all the big and hard to drive headphones I’ve thrown at it: AKG K501, K340, Hifiman’s HE5, as well as some really tough Orthodynamics, including a super inefficient 120Ω SFI Orthodynamic driver. Surprisingly, though having all that power, yet the Beta22’s sound signature falls more to the relaxed side. Sometimes we mistakenly equate “power” with “agressive sound”. I know I often make that mistake. The Beta22 is not slow or mellow like some tube amplifiers are, but it doesn’t particularly sound too energetic either. For instance, I’ve found that other amplifiers like the Burson HA-160 to be more energetic, and the Lehmann Black Cube Linear to have a much faster speed than the Beta22. Of course some headphones like the Hifiman HE5 have its character so strongly embedded in the chain, that the Beta22 would not sound relaxed, but ultimately its sound are quite relaxed, and it’s up to you to decide if the signature is for you.
Being totally neutral in the frequency balance means that music may have less wow effect than some lesser amplifiers. This is where a good musical source is crucial with the Beta22. Some amps boosts the bass frequencies to get a more groovy sound. Some amps boost the upper midrange to sound intimate. Some amps boost the treble to get the impression of clarity and detail. Some amps have a subtle V-shaped curve to make the sound more lively. A lot of people would be happier with some emphasis in some part of the frequency range, but they’re not going to get it with the Beta22. This is when a good knowledge of the character of each gear in the chains is needed. So you can know what source and what headphone will work well with the Beta22 for the music that you’re listening to. Otherwise you can always opt to go the non-purist way and install a good equalizer.
The Beta22 is quite revealing of the source’s character, but I also find it to have a particular sound signature of its own. Most of the time I’m using the warm sounding CEC TL51XZ CD player for the source. But even with sources that tend to sound bright like the Lavry DA11 and the Buffalo24, I never find the Beta22 to get anywhere close to cold sounding. This is good for music listening purposes, as most people avoid a cold sounding set up at all cost. Plus, despite sounding warm, the Beta always maintain a good amount of clarity and it never gets muddy.