Tanchjim Space: power output and what it will drive

The Tanchjim Space is a USB dongle at $70. It delivers 125 mW into 32Ω and 13 mW into 300Ω, which ranks it 69 of 88 for raw power among the sources in this database.

Measured at 100 dB SPL it has comfortable headroom on 264 of the 310 dynamic and planar headphones catalogued here, enough but not generous on 44 and only marginal on 2. Cheap, tiny and balanced, aimed squarely at in-ears rather than full-size headphones.

What it actually puts out

TypeUsb dongle
Price$70
Power into 32 Ω125 mW
Power into 150 Ω27 mW
Power into 300 Ω13 mW
Power into 600 Ω6.7 mW
Output impedancenot published
Output noise1.1 µV
Comfortable headroom on 264 of 310 headphones (85%) · marginal on 2

Where these numbers come from

The manufacturer publishes a maximum output of 2.0 V but no power rating at any load. Every figure above is therefore a ceiling: the real output into a low impedance will be lower, possibly much lower.

The balanced output is rated separately: 500 mW into 32Ω through the 4.4mm jack.

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.

Source: tanchjim.com.

LoadPowerStatusHow it was arrived at
32 Ω125 mWUpper boundthe manufacturer publishes a maximum output voltage but no power rating, so this is a ceiling, not a rating
150 Ω27 mWUpper boundthe manufacturer publishes a maximum output voltage but no power rating, so this is a ceiling, not a rating
300 Ω13 mWUpper boundthe manufacturer publishes a maximum output voltage but no power rating, so this is a ceiling, not a rating
600 Ω6.7 mWUpper boundthe manufacturer publishes a maximum output voltage but no power rating, so this is a ceiling, not a rating

Against 41 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 HE-6se 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.

HeadphoneImpedancedB/mWNeedsHeadroomVerdict
Shure SE8469 Ω114.00.04 mW+29 dBComfortable audible hiss
64 Audio U12t13 Ω108.00.16 mW+25 dBComfortable faint hiss
Shure SE21517 Ω107.00.20 mW+25 dBComfortable faint hiss
Moondrop Aria32 Ω107.00.20 mW+28 dBComfortable faint hiss
Sennheiser IE 20018 Ω104.00.40 mW+22 dBComfortable faint hiss
Audeze LCD-X 202120 Ω103.00.50 mW+22 dBComfortable faint hiss
Sennheiser HD 25 (1-II)70 Ω108.00.16 mW+26 dBComfortable faint hiss
Sony MDR-750663 Ω106.00.25 mW+24 dBComfortable
Meze 99 Classics32 Ω103.00.50 mW+24 dBComfortable
Focal Clear MG55 Ω104.00.40 mW+23 dBComfortable
Philips SHP950032 Ω101.00.79 mW+22 dBComfortable
Truthear Hexa21 Ω99.01.3 mW+18 dBComfortable
Focal Utopia80 Ω104.00.40 mW+21 dBComfortable
Meze Empyrean32 Ω100.01.0 mW+21 dBComfortable
Campfire Audio Andromeda 20209 Ω94.04.0 mW+9 dBEnough
Etymotic ER2SE15 Ω96.02.5 mW+14 dBComfortable
AKG K37132 Ω99.01.3 mW+20 dBComfortable
Grado SR80x32 Ω99.01.3 mW+20 dBComfortable
Audio-Technica ATH-M50X38 Ω99.01.3 mW+19 dBComfortable
Beyerdynamic DT 900 Pro X48 Ω100.01.0 mW+19 dBComfortable
Audeze LCD-2 Classic70 Ω101.00.79 mW+19 dBComfortable
Dan Clark Audio AEON 2 Closed13 Ω92.06.3 mW+9 dBEnough
Sennheiser HD 560S120 Ω101.00.79 mW+16 dBComfortable
HiFiMAN Edition XS18 Ω92.06.3 mW+10 dBComfortable
HiFiMAN Arya Stealth32 Ω94.04.0 mW+15 dBComfortable
Audeze LCD-514 Ω90.010 mW+7 dBEnough
HiFiMAN Sundara37 Ω94.04.0 mW+14 dBComfortable
Beyerdynamic DT 1990 Pro (250Ω)250 Ω102.00.63 mW+14 dBComfortable
HiFiMAN HE400se32 Ω91.07.9 mW+12 dBComfortable
AKG K70262 Ω93.05.0 mW+11 dBComfortable
Fostex T50RP MK350 Ω92.06.3 mW+11 dBComfortable
ZMF Verite Closed300 Ω99.01.3 mW+10 dBComfortable
Dan Clark Audio Stealth23 Ω87.020 mW+7 dBEnough
Sennheiser HD 650300 Ω98.01.6 mW+9 dBEnough
ZMF Atrium300 Ω98.01.6 mW+9 dBEnough
Audio-Technica ATH-R70X470 Ω99.01.3 mW+8 dBEnough
Sennheiser HD 600300 Ω97.02.0 mW+8 dBEnough
Sennheiser HD 800S300 Ω97.02.0 mW+8 dBEnough
Beyerdynamic DT 770 Pro (250Ω)250 Ω96.02.5 mW+8 dBEnough
Abyss AB-1266 Phi TC42 Ω88.016 mW+8 dBEnough
HiFiMAN Susvara60 Ω83.050 mW+1 dBMarginal

Will it hiss?

At 1.1 µV of output noise, here is where that noise lands in the five most revealing in-ears in the database.

This one hisses. With the most sensitive in-ears in the database its own noise lands around 15 dB SPL, which you will hear between tracks and in quiet passages.

In-earImpedanceSensitivityHiss level
Shure SE8469 Ω134.5 dB/V15 dB SPL
Moondrop Quarks16 Ω131.0 dB/V12 dB SPL
64 Audio U4s12 Ω127.2 dB/V8 dB SPL
64 Audio U6t12 Ω127.2 dB/V8 dB SPL
Audeze LCD-i320 Ω127.0 dB/V8 dB SPL

Output impedance and the one-eighth rule

The manufacturer does not publish an output impedance for this source. That is the one number that decides whether it leaves your headphones alone or acts as a tone control, so its absence matters more than it looks: without it, nothing here can tell you how this source will behave with a multi-driver in-ear.

If you find a measured figure you trust, the checker will work out the consequence for any headphone.

Other dongles 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.