One thing these Amphions don't lack is enthusiasm. They've got a hard-charging attitude that helps them sound bold and punchy.
As you'd imagine, this kind of presentation works a treat on music such as Massive Attack's Heligoland where the Helium 510's speed and agility work well. There's a decent amount of detail as well as the ability to pound out high-level transients with ease.
These speakers are relatively compact (31cm tall), so properly deep bass is off the menu, but that 13cm paper coned mid/bass driver doesn't want for trying.
One of Amphion's trademarks is a low crossover point: 1.6kHz. That's well below the 2.5-3.5kHz that most speakers operate at. This takes the crossover point out of the region where most people are most sensitive to it.
It'll come as no surprise that the Heliums are well integrated, in the tonal sense at least. Where they're less successful is in matching the character of the mid and treble to that of the bass.
Midrange upwards, these speakers sound incredibly taut and solid. They project sound strongly, in a way that makes most rivals seem a little reserved.
The bass, on the other hand, sounds a little soft and fluffy in comparison, and this leads to a rather uneven presentation.
Flat dynamics disappoint
Other weaknesses include an inability to deliver varied dynamics of the kind that keeps music interesting, be it a Schubert symphony or Kanye West's Love Lockdown. You can add restricted refinement and hazy timing to the negatives.
The Helium 510s counter these flaws with decent build quality and the ability to play loudly with conviction, but that isn't enough to save this Finnish speaker from an average rating.
It just hasn't got the weaponry to worry rivals such as ATCs SCM 11s or Roksan Kandy K2 speakers.
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