Schiit Vali 2+: power output and what it will drive

The Schiit Vali 2+ is a desktop amplifier at $149. It delivers 1.5 W into 32Ω and 400 mW into 300Ω, which ranks it 59 of 280 for raw power among the sources in this database.

Measured at 100 dB SPL it has comfortable headroom on 563 of the 567 dynamic and planar headphones catalogued here, enough but not generous on 3 and only marginal on 1. Hybrid tube/solid-state. Use with high-impedance headphones only.

What it actually puts out

TypeDesktop amplifier
Price$149
Power into 32 Ω1.5 W
Power into 150 Ω496 mW
Power into 300 Ω400 mW
Power into 600 Ω200 mW
Output impedance1.8 Ω
Output noise25 µV unverified
Comfortable headroom on 563 of 567 headphones (99%) · marginal on 1

Where these numbers come from

The manufacturer publishes 1.5 W into 32Ω, 1.0 W into 50Ω, 400 mW into 300Ω, 200 mW into 600Ω. Everything else in the table above is worked out from those figures, and this table says which is which.

Derivation holds output voltage steady between and beyond the published loads rather than output power, because that is what an amplifier actually does. The full method is written up here.

The output noise shown above did not turn up in any manufacturer document during this check. It is carried over from the material this database was first built from, and is marked unverified rather than quietly presented as sourced.

Source: stereophile.com, schiit.com, schiit-europe.com.

LoadPowerStatusHow it was arrived at
32 Ω1.5 WPublishedthe manufacturer publishes this figure at this exact load
50 Ω1.0 WPublishedthe manufacturer publishes this figure at this exact load
150 Ω496 mWDerivedworked out between two published loads, holding output voltage linear between them
300 Ω400 mWPublishedthe manufacturer publishes this figure at this exact load
600 Ω200 mWPublishedthe manufacturer publishes this figure at this exact load

Against 40 well-known headphones

Ordered from easiest to hardest to drive. Headroom is measured at 100 dB SPL, which is louder than almost anyone listens — a small negative number means the source still plays loud, just without reserve for peaks.

These figures come from each manufacturer's own sensitivity rating. A handful of planars — the HiFiMAN Susvara and the Abyss AB-1266 in particular — are widely reported to need far more than their published sensitivity implies, so treat a bare pass on those as optimistic rather than settled.

HeadphoneImpedanceSensitivityNeedsHeadroomVerdict
Shure SE8469 Ω114.0 dB/mW0.04 mW+40 dBComfortable audible hiss, damping
64 Audio U12t12.6 Ω108.0 dB/mW0.16 mW+36 dBComfortable audible hiss, damping
Shure SE21517 Ω107.0 dB/mW0.20 mW+36 dBComfortable audible hiss
Moondrop Aria32 Ω107.1 dB/mW0.19 mW+39 dBComfortable audible hiss
Audeze LCD-X 202120 Ω103.0 dB/mW0.50 mW+33 dBComfortable audible hiss
Truthear Hexa20.5 Ω103.1 dB/mW0.49 mW+33 dBComfortable audible hiss
Sennheiser IE 20018 Ω101.6 dB/mW0.69 mW+31 dBComfortable audible hiss
Sony MDR-750663 Ω106.0 dB/mW0.25 mW+35 dBComfortable audible hiss
Meze 99 Classics32 Ω103.0 dB/mW0.50 mW+35 dBComfortable audible hiss
Focal Clear MG55 Ω104.0 dB/mW0.40 mW+34 dBComfortable audible hiss
Philips SHP950032 Ω101.0 dB0.79 mW+33 dBComfortable audible hiss
Focal Utopia80 Ω104.0 dB/mW0.40 mW+33 dBComfortable audible hiss
Meze Empyrean32 Ω100.0 dB1.0 mW+32 dBComfortable audible hiss
Campfire Audio Andromeda 20209 Ω94.0 dB4.0 mW+20 dBComfortable audible hiss, damping
Etymotic ER2SE15 Ω96.0 dB/mW2.5 mW+24 dBComfortable audible hiss
AKG K37132 Ω99.1 dB/mW1.2 mW+31 dBComfortable audible hiss
Audio-Technica ATH-M50X38 Ω99.0 dB/mW1.3 mW+30 dBComfortable audible hiss
Beyerdynamic DT 900 Pro X48 Ω100.0 dB/mW1.0 mW+30 dBComfortable audible hiss
Audeze LCD-2 Classic70 Ω101.0 dB/mW0.79 mW+30 dBComfortable audible hiss
Grado SR80x38 Ω98.0 dB/mW1.6 mW+29 dBComfortable audible hiss
Sennheiser HD 560S120 Ω100.8 dB/mW0.83 mW+28 dBComfortable audible hiss
HiFiMAN Edition XS18 Ω92.0 dB6.3 mW+21 dBComfortable audible hiss
HiFiMAN Arya Stealth32 Ω94.0 dB4.0 mW+26 dBComfortable audible hiss
Dan Clark Audio AEON 2 Closed13 Ω90.0 dB/mW10 mW+18 dBComfortable audible hiss, damping
Audeze LCD-514 Ω90.0 dB/mW10 mW+18 dBComfortable audible hiss, damping
Beyerdynamic DT 1990 Pro (250Ω)250 Ω102.0 dB/mW0.63 mW+28 dBComfortable audible hiss
HiFiMAN HE400se25 Ω91.0 dB7.9 mW+22 dBComfortable audible hiss
HiFiMAN Sundara32 Ω92.0 dB6.3 mW+24 dBComfortable audible hiss
Dan Clark Audio Stealth23 Ω90.0 dB/mW10 mW+20 dBComfortable audible hiss
Fostex T50RP MK350 Ω92.0 dB/mW6.3 mW+22 dBComfortable audible hiss
AKG K70262 Ω92.9 dB/mW5.1 mW+22 dBComfortable audible hiss
ZMF Verite Closed300 Ω99.0 dB/mW1.3 mW+25 dBComfortable audible hiss
Sennheiser HD 650300 Ω97.8 dB/mW1.7 mW+24 dBComfortable audible hiss
Sennheiser HD 800S300 Ω96.8 dB/mW2.1 mW+23 dBComfortable faint hiss
Beyerdynamic DT 770 Pro (250Ω)250 Ω96.0 dB2.5 mW+22 dBComfortable faint hiss
Audio-Technica ATH-R70X470 Ω98.0 dB/mW1.6 mW+22 dBComfortable faint hiss
ZMF Atrium300 Ω96.0 dB/mW2.5 mW+22 dBComfortable faint hiss
Abyss AB-1266 Phi TC50 Ω88.0 dB/mW16 mW+18 dBComfortable faint hiss
Sennheiser HD 600300 Ω91.8 dB/mW6.6 mW+18 dBComfortable faint hiss
HiFiMAN Susvara60 Ω83.0 dB50 mW+12 dBComfortable faint hiss

Will it hiss?

At 25 µV of output noise, here is where that noise lands in the five most revealing in-ears in the database.

That noise figure has not been traced to a document from the maker, so the levels below are as good as the number they start from.

This one hisses. With the most sensitive in-ears in the database its own noise lands around 49 dB SPL, which you will hear between tracks and in quiet passages.

In-earImpedanceSensitivityHiss level
Simgot EA50016 Ω141.0 dB/V49 dB SPL
Tanchjim EA FORCE17 Ω137.7 dB/V46 dB SPL
Shure SE8469 Ω134.5 dB/V42 dB SPL
Campfire Audio Clara13.3 Ω134.1 dB/V42 dB SPL
64 Audio Fourte10 Ω134.0 dB/V42 dB SPL

Output impedance and the one-eighth rule

At 1.8Ω output impedance, the one-eighth rule says this source suits headphones of 14.4Ω and above. 72 of the 567 models here fall below that. Most of them are multi-driver in-ears, and the mismatch tilts the frequency response audibly rather than subtly.

The rule is a rule of thumb, not physics: a source impedance below one eighth of the headphone's keeps the interaction under about 1 dB. The checker works it out for any pair.

The cheapest thing here that does the same job

SourceTypePriceInto 300 ΩOutput impedanceOutput noise
Schiit Magni Heresydesktop amplifier$99410 mW0.25 Ω1.5 µV unverified
Schiit Magni Unitydesktop amplifier$119415 mW0.1 Ω1.59 µV
JDS Labs Atom Amp 2desktop amplifier$129284 mW0.7 Ω1.33 µV

Of the 280 sources here, 4 do everything the Schiit Vali 2+ does as a headphone output: reach 100 dB on every headphone it reaches and stay inside the one-eighth rule wherever it does. The cheapest of them is the Schiit Magni Heresy at $99, against this one’s $149 — $50 less.

This counts a headphone output and nothing else. Inputs, converters, microphone preamps, balanced outputs, the volume control, the case and the warranty are all outside it, and any of them can be the reason to buy the dearer box. What the count does say is that the three numbers a maker can be held to do not separate them.

Other desktop amplifiers at a similar price

Or put any two side by side in the source comparison tool, or run your own headphones through the amplifier matcher. Or see every Schiit source in the database, and how much of what this site says about them came from Schiit’s own documents.

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