Simgot EW300: how much amplifier do you need?

The Simgot EW300 is 28Ω with a sensitivity of 105.5 dB/mW, which is 121.0 dB/V. To reach 100 dB SPL — genuinely loud, louder than most people listen — it needs 0.28 mW, or 89 mV across the drivers.

That puts it in the easy category. A phone, a laptop headphone jack or the cheapest USB dongle will drive it to painful levels. Of the 156 sources in the database, 156 have comfortable headroom. The cheapest portable source that does the job is the Apple USB-C dongle (US) at $9.

The two numbers that decide everything

Impedance28 Ω
Sensitivity105.5 dB/mW
Sensitivity (voltage)121.0 dB/V
TypeIn-ear monitor
BrandSimgot
Easy to drive — anything will do it

Sensitivity here is in dB per milliwatt. Manufacturers often quote dB per volt instead and leave the unit off, which is the single most common reason online calculators give answers that are 10–15 dB wrong. The converter explains the difference.

Where this sensitivity figure comes from

Simgot publishes this as 121 dB/Vrms (@1kHz, silver steel tube + red silicone ring) — a figure per volt, not per milliwatt. At 28Ω the two differ by 15.5 dB, so the 105.5 dB/mW above is that published number converted, not a different measurement.

This is the conversion that online calculators skip. Quote the per-volt number as if it were per-milliwatt and this headphone looks 16 dB easier to drive than it is — which is roughly the difference between a dongle being enough and not being enough.

Source: linsoul.com. How this data was built.

Power, voltage and current by listening level

LevelWhat it isPowerVoltageCurrent
85 dB SPLquiet background listening0.01 mW16 mV0.6 mA
95 dB SPLnormal listening0.09 mW50 mV1.8 mA
100 dB SPLloud listening0.28 mW89 mV3.2 mA
105 dB SPLvery loud0.89 mW0.16 V5.6 mA
110 dB SPLpeaks on dynamic music2.8 mW0.28 V10.0 mA

Most people listen between 75 and 85 dB. The 100 dB row is the one worth planning around: it gives you headroom for dynamic peaks without designing your system for a volume that would damage your hearing in under fifteen minutes. The safe listening calculator puts numbers on that.

What drives them, from a $9 dongle upwards

Every source in the database, judged at 100 dB SPL into 28Ω. “Headroom” is how much power is left over above what the headphone needs — 10 dB means ten times the required power, which is what you want for dynamic peaks.

SourceTypePricePower into 28ΩHeadroomVerdict
Wells Audio Milodesktop amplifier$170010.5 W+46 dBComfortable faint hiss
Gustard H26desktop amplifier$10998.5 W+45 dBComfortable
Chord Hugo TT 2desktop amplifier$50007.0 W+44 dBComfortable faint hiss
Schiit Lyr+desktop amplifier$4496.4 W+44 dBComfortable
Singxer SA-1desktop amplifier$6996.1 W+43 dBComfortable
Topping A30 Prodesktop amplifier$2495.5 W+43 dBComfortable
Schiit Ragnarok 2desktop amplifier$14995.2 W+43 dBComfortable faint hiss
Schiit Midgarddesktop amplifier$2194.8 W+42 dBComfortable
Burson Soloist 3X GTdesktop amplifier$27994.1 W+42 dBComfortable faint hiss
Violectric V550 Prodesktop amplifier$36004.0 W+42 dBComfortable audible hiss
Benchmark HPA4desktop amplifier$34993.7 W+41 dBComfortable faint hiss
Schiit Asgard 3desktop amplifier$2793.7 W+41 dBComfortable faint hiss
iFi iCAN Prodesktop amplifier$6003.5 W+41 dBComfortable audible hiss
SMSL SH-9desktop amplifier$2893.4 W+41 dBComfortable faint hiss
SMSL HO200desktop amplifier$3993.4 W+41 dBComfortable faint hiss
SMSL SP400desktop amplifier$5293.4 W+41 dBComfortable faint hiss
SMSL DO400desktop DAC/amp$5203.4 W+41 dBComfortable
Topping L50desktop amplifier$2292.9 W+40 dBComfortable
JDS Labs Element IVdesktop DAC/amp$5492.8 W+40 dBComfortable faint hiss
Topping L30 IIdesktop amplifier$1492.8 W+40 dBComfortable
iFi Pro iCAN Signaturedesktop amplifier$24992.7 W+40 dBComfortable
xDuoo TA-30desktop amplifier$7092.6 W+40 dBComfortable
Cayin HA-6Adesktop amplifier$18002.6 W+40 dBComfortable audible hiss
RME ADI-2 Pro FS Raudio interface$21992.6 W+40 dBComfortable
Schiit Magni Unitydesktop amplifier$1192.5 W+40 dBComfortable
Schiit Magni Heresydesktop amplifier$992.4 W+39 dBComfortable faint hiss
Violectric V222desktop amplifier$12452.4 W+39 dBComfortable audible hiss
SPL Phonitor xedesktop amplifier$30002.4 W+39 dBComfortable audible hiss
JDS Labs Atom Amp 2desktop amplifier$1292.3 W+39 dBComfortable faint hiss
Little Dot MK III SEdesktop amplifier$5402.2 W+39 dBComfortable
Topping A90 Discretedesktop amplifier$5992.2 W+39 dBComfortable
Violectric V226desktop DAC/amp$16002.0 W+39 dBComfortable audible hiss
Fiio K9 Prodesktop DAC/amp$7991.8 W+38 dBComfortable faint hiss
Schiit Magni+desktop amplifier$1091.8 W+38 dBComfortable faint hiss
Schiit Jotunheim 2desktop amplifier$3991.8 W+38 dBComfortable
Topping A90desktop amplifier$4991.8 W+38 dBComfortable
SMSL HO100desktop amplifier$1601.7 W+38 dBComfortable faint hiss
Geshelli Archel Prodesktop amplifier$2001.6 W+37 dBComfortable faint hiss
Topping DX5desktop DAC/amp$4491.6 W+37 dBComfortable
iFi Zen CANdesktop amplifier$1991.4 W+37 dBComfortable faint hiss
Headamp GS-X Minidesktop amplifier$17951.4 W+37 dBComfortable faint hiss
Schiit Vali 2+desktop amplifier$1491.3 W+37 dBComfortable audible hiss
Questyle CMA Fifteendesktop DAC/amp$24991.3 W+37 dBComfortable
Lake People G111 Mk IIdesktop amplifier$6291.2 W+36 dBComfortable audible hiss
Benchmark DAC3 HGCdesktop DAC/amp$23991.2 W+36 dBComfortable
Grace Design m900desktop amplifier$6601.1 W+36 dBComfortable audible hiss
Geshelli Archel 3S Prodesktop amplifier$3701.1 W+36 dBComfortable
JDS Labs Element III MK2desktop DAC/amp$4491.1 W+36 dBComfortable faint hiss
Lynx Aurora(n)audio interface$34991.1 W+36 dBComfortable
RME ADI-2 DAC FSaudio interface$13991.1 W+36 dBComfortable
Fiio K7desktop DAC/amp$1991.1 W+36 dBComfortable audible hiss
SSL 12audio interface$5991.0 W+36 dBComfortable
Apogee Duet 3audio interface$6491.0 W+36 dBComfortable
Schiit Magni Pietydesktop amplifier$2001.0 W+36 dBComfortable
Matrix mini-i Pro 4desktop DAC/amp$14991.0 W+36 dBComfortable damping
Matrix element M2desktop DAC/amp$29991.0 W+36 dBComfortable damping
Ferrum OORdesktop amplifier$1995933 mW+35 dBComfortable faint hiss
xDuoo XD05 Balportable amplifier$499875 mW+35 dBComfortable
JDS Labs Atom+ (2nd gen)desktop amplifier$99875 mW+35 dBComfortable faint hiss
Lake People G103-S Mk IIdesktop amplifier$350875 mW+35 dBComfortable audible hiss
Schiit Mjolnir 3desktop amplifier$1199875 mW+35 dBComfortable audible hiss
SPL Phonitor sedesktop amplifier$1600875 mW+35 dBComfortable audible hiss
SPL Phonitor xdesktop amplifier$3200875 mW+35 dBComfortable audible hiss
Merging Anubisaudio interface$2790841 mW+35 dBComfortable
HiBy R6 Pro IIportable player$750656 mW+34 dBComfortable audible hiss
FiiO Q7portable amplifier$750575 mW+33 dBComfortable faint hiss
FiiO M17portable player$1799532 mW+33 dBComfortable audible hiss
Fosi Audio K7desktop DAC/amp$199525 mW+33 dBComfortable faint hiss
Woo Audio WA6desktop amplifier$1099507 mW+33 dBComfortable
Apogee Symphony Desktopaudio interface$1495485 mW+32 dBComfortable
Qudelix T71USB dongle$229438 mW+32 dBComfortable faint hiss
Bryston BHA-1desktop amplifier$2395438 mW+32 dBComfortable
MOTU UltraLite-mk5audio interface$699412 mW+32 dBComfortable
SSL 2 MkIIaudio interface$229327 mW+31 dBComfortable
SSL 2 Plus MkIIaudio interface$299327 mW+31 dBComfortable
RME Babyface Pro FSaudio interface$899327 mW+31 dBComfortable audible hiss, damping
iBasso DX180portable player$480300 mW+30 dBComfortable
iBasso DX260portable player$949300 mW+30 dBComfortable
Astell&Kern SP3000portable player$3700298 mW+30 dBComfortable audible hiss
MOTU M2audio interface$219292 mW+30 dBComfortable
MOTU M4audio interface$279292 mW+30 dBComfortable
MOTU M6audio interface$499292 mW+30 dBComfortable
FiiO BTR17Bluetooth receiver$199284 mW+30 dBComfortable audible hiss
Astell&Kern SR35portable player$800263 mW+30 dBComfortable audible hiss
Questyle M15USB dongle$250262 mW+30 dBComfortable audible hiss
FiiO JM21portable player$199260 mW+30 dBComfortable faint hiss
Rupert Neve RNHPdesktop amplifier$699251 mW+29 dBComfortable audible hiss
Tempotec Sonata BHD ProUSB dongle$60245 mW+29 dBComfortable audible hiss
Moondrop Moonriver 2 TiUSB dongle$190245 mW+29 dBComfortable faint hiss
iFi hip-dac 3portable amplifier$199245 mW+29 dBComfortable
Bottlehead Crack (OTL kit)desktop amplifier$375237 mW+29 dBComfortable damping
ddHiFi TC44 Pro E2USB dongle$99219 mW+29 dBComfortable
Cayin N3 Ultraportable player$649219 mW+29 dBComfortable
FiiO M11Sportable player$499214 mW+29 dBComfortable faint hiss
Apogee BOOMaudio interface$299210 mW+29 dBComfortable
FiiO KA11USB dongle$29204 mW+29 dBComfortable faint hiss
FiiO KA15USB dongle$109195 mW+28 dBComfortable faint hiss
RME Fireface UCX IIaudio interface$1749184 mW+28 dBComfortable
iFi Zen DAC 3desktop DAC/amp$229184 mW+28 dBComfortable
Fosi Audio SK02desktop amplifier$100166 mW+28 dBComfortable
Arturia AudioFuse Rev2audio interface$599164 mW+28 dBComfortable damping
FiiO BTR7Bluetooth receiver$199158 mW+27 dBComfortable audible hiss
iFi GO bluBluetooth receiver$219144 mW+27 dBComfortable
iBasso DC-EliteUSB dongle$449142 mW+27 dBComfortable
FiiO M23portable player$699141 mW+27 dBComfortable faint hiss
Cayin RU7USB dongle$269140 mW+27 dBComfortable
FiiO KA17USB dongle$149132 mW+27 dBComfortable faint hiss
Aiyima A2 Prodesktop DAC/amp$75131 mW+27 dBComfortable
FiiO BTR15Bluetooth receiver$109130 mW+27 dBComfortable faint hiss
Zoom UAC-232audio interface$399129 mW+27 dBComfortable damping
Shanling M3 Ultraportable player$479123 mW+26 dBComfortable
FiiO KA5USB dongle$99122 mW+26 dBComfortable faint hiss
Arturia MiniFuse 2audio interface$149122 mW+26 dBComfortable damping
Hidizs S9 Pro PlusUSB dongle$139121 mW+26 dBComfortable
Shanling UA5USB dongle$259120 mW+26 dBComfortable audible hiss
Truthear SHIOUSB dongle$70109 mW+26 dBComfortable faint hiss
Tanchjim SpaceUSB dongle$70109 mW+26 dBComfortable faint hiss
Moondrop Dawn ProUSB dongle$75109 mW+26 dBComfortable faint hiss
iBasso DC04 ProUSB dongle$119109 mW+26 dBComfortable faint hiss
Astell&Kern HC3USB dongle$179109 mW+26 dBComfortable
Astell&Kern HC4USB dongle$219109 mW+26 dBComfortable
Qudelix 5KBluetooth receiver$109109 mW+26 dBComfortable audible hiss
Audient iD24audio interface$599108 mW+26 dBComfortable damping
ddHiFi TC44 ProUSB dongle$189105 mW+26 dBComfortable faint hiss
Audient iD4 MkIIaudio interface$199104 mW+26 dBComfortable
Audient iD14 MkIIaudio interface$349104 mW+26 dBComfortable
FiiO BTR13Bluetooth receiver$59102 mW+26 dBComfortable faint hiss
Schiit Valhalla 2desktop amplifier$349101 mW+26 dBComfortable damping
Shanling UP5Bluetooth receiver$17998 mW+25 dBComfortable audible hiss
ART HeadAmp 4 Prodesktop amplifier$13093 mW+25 dBComfortable damping
PreSonus Quantum ES 2audio interface$19992 mW+25 dBComfortable
Hidizs S9 ProUSB dongle$10988 mW+25 dBComfortable audible hiss
Little Dot MK IIdesktop amplifier$17688 mW+25 dBComfortable
iBasso DC03 ProUSB dongle$6986 mW+25 dBComfortable faint hiss
PreSonus Studio 68caudio interface$29975 mW+24 dBComfortable
Universal Audio Volt 2audio interface$19974 mW+24 dBComfortable
Universal Audio Volt 276audio interface$29974 mW+24 dBComfortable
Steinberg UR44Caudio interface$34970 mW+24 dBComfortable
PreSonus HP4desktop amplifier$15061 mW+23 dBComfortable
FiiO KA13USB dongle$7953 mW+23 dBComfortable faint hiss
Generic CX31993 donglesUSB dongle$1252 mW+23 dBComfortable audible hiss
EarStudio ES100 MK2Bluetooth receiver$9052 mW+23 dBComfortable audible hiss
Focusrite Scarlett 4i4 4th genaudio interface$27948 mW+22 dBComfortable damping
Focusrite Scarlett 18i20 4th genaudio interface$69948 mW+22 dBComfortable damping
Sony NW-WM1AM2portable player$139934 mW+21 dBComfortable audible hiss
Steinberg IXO22audio interface$11928 mW+20 dBComfortable
Focusrite Scarlett Solo 4th genaudio interface$13927 mW+20 dBComfortable damping
Focusrite Scarlett 2i2 4th genaudio interface$19927 mW+20 dBComfortable damping
Apple USB-C dongle (US)USB dongle$926 mW+20 dBComfortable audible hiss
JadeAudio JA11USB dongle$2026 mW+20 dBComfortable faint hiss
PreSonus Studio 24caudio interface$14924 mW+19 dBComfortable
Audient EVO 4audio interface$12921 mW+19 dBComfortable damping
Audient EVO 8audio interface$24921 mW+19 dBComfortable damping
Sony NW-A306portable player$35020 mW+19 dBComfortable audible hiss
Apple USB-C dongle (EU)USB dongle$913 mW+17 dBComfortable audible hiss
Steinberg UR22Caudio interface$19910 mW+16 dBComfortable

The three ways a source goes wrong

Hiss. At 121.0 dB/V these are sensitive enough to reveal a source's own noise floor. The noisiest source in the database, the Schiit Vali 2+, would put its hiss at roughly 29 dB SPL in these headphones — clearly audible in quiet passages. The hiss calculator lets you check your own amplifier's noise figure.

Output impedance. At 28Ω these want a source output impedance below 3.50Ω to satisfy the one-eighth rule. 16 of the 156 sources here miss it, the worst being the Bottlehead Crack (OTL kit) at 120.0Ω. Above that threshold the source starts shaping the frequency response. Check yours here.

Similar headphones

Or open the comparison tool to put any two models side by side, or browse all 402.