Our Take

The iFi micro iDSD Signature is the latest in iFi’s line of highly adaptable portable DAC/amp combos. The Signature follows up from the Black Label and provides some tweaks to the design as well as upgrades to the digital and analog sections of the device that take the iDSD Signature's sound to the next level.

Read the full review

From iFi

Sporting a Space Blue finish and powered by a built-in rechargeable battery, the micro iDSD Signature is a transportable DAC/headphone amp that’s ready for anything that the universe throws at it.

Battery power means it’s ultra-clean with ultra-stable DC power and avoids the pitfalls of AC mains – dips, spike and noise-inducing RFI/EMI pollution.

And with up to 12 hours playing time, depending on the headphones and performance mode engaged, it feels like you could take it to the moon and back.

iFi Micro iDSD Signature

Finely Tuned

Based around two Burr-Brown DAC chips in a custom ‘interleaved’ configuration, the digital engine has four pairs of differential signals – two pairs per channel. This means

a lower noise floor
improved channel separation
finer musical detail and micro-dynamics

The micro iDSD Signature handles up to PCM 768, DSD 512, 2xDXD and MQA. All this is done natively. Both PCM and DSD remain ‘bit-perfect’.

Precision Personified

Extensive jitter-eradication technologies are applied to the digital engine, including iFi’s GMT (Global Master Timing) femto-precision clock and the intelligent memory buffer.

The micro iDSD Signature also comes with iFi’s GTO (Gibbs Transient Optimized) digital filter installed. And exclusive firmware available on our website means you can change digital filters as you wish.

Circuit Training

With up to 4100mW of power the micro iDSD Signature can drive all manner of headphones with aplomb, from highly sensitive in-ear monitors to current hungry planar headphones.

The signal path has been refined to maximise sonic texture. High spec components featuring class-leading qualities such as low ESR (Equivalent Series Resistance), high stability and low distortion mean top-notch sound quality and maximum musical enjoyment.

Add in the direct-coupled nature of the circuit – no coupling capacitor is present – and the micro iDSD Signature definitely runs rings around the competition.

Versatile Sonic Tailoring

One size no longer fits all when it comes to quality listening.

The digital stage of the micro iDSD Signature features a variety of filter settings:

‘Standard’, ‘Minimum Phase’ and ‘Bit-Perfect’ for PCM files
‘Standard Bandwidth’, ‘Extended Bandwidth’ and ‘Extreme Bandwidth’ for DSD

The amp stage also has three settings to adjust power and gain. As well as ‘Normal’, you get

‘Turbo’ to ramp up the level of drive for current-hungry headphones
‘Eco’ to dial down the power to suit high-sensitivity in-ear monitors and/or to extend battery life

Complete this with our iEMatch technology that adjusts output level and our XBass+ and 3D+ signature sonic tweaks, and the micro iDSD Signature is flexible to the max.

iFi Micro iDSD Signature

Get Connected

The micro iDSD Signature features two digital audio inputs – USB Type-A and an S/PDIF socket that accepts both electrical, via a 3.5mm connector, and optical signals – adapter supplied.

It also houses a pair of RCA analogue outputs to connect to a pair of powered speakers or a power amp and passive speakers, to act as a DAC and preamplifier.

There is a 6.3mm output for headphones that have a standard single-ended connector (headphones with a 3.5mm jack can be connected using an adapter) and a 4.4mm Pentaconn output for headphones offering balanced connection.

Both headphone outputs utilise our ‘S-Balanced’ output circuitry. This delivers the sonic benefits of balanced connections with all headphone/earphone types – even those with single-ended connectors – cutting crosstalk and associated distortion in half.

Highlights

The Burr-Brown True Native® chipset means file formats remain unchanged. Listen to music as the artist intended in the format in which it was recorded.
Doubling the DAC chips results in 3dB lower noise floor and better channel separation. Together with power supply advancements and advanced channel interleaving, the noise floor has been halved.
Hi-Res True Native® playback for all music formats from MP3 to DSD512, PCM768 and 2xDXD.
Listen to Master Quality Authenticated audio straight out of the box. Connect to Tidal Masters and check the option to stream MQA.
This OV series operational amplifier is another example of a top-notch component used to get extremely low noise, low distortion (0.0001%) and wide bandwidth.
With output power up to 4,100mW, this headphone amplifier drives all headphones with ease. It has 3 power modes – Eco, Normal and Turbo. Power and gain can be dialled-in perfectly to suit ALL headphones.
iFi’s exclusive S-Balanced® circuit delivers maximum performance from single-ended and balanced headphones alike.
3D+ Holographic® delivers an immersive, deep soundstage. Check it out here.
XBass+® delivers a deep, tighter bass sound. Discover the details.
TI low-noise ICs offer great unity gain bandwidth, very low noise and distortion, high output drive capability, Common-mode and Power Supply Rejection Ratios of over 100 dB, wide maximum-output-swing bandwidths and high slew rates.
iFi always uses the best components possible. These OS-CON™ capacitors provide excellent noise reduction and have a long life span. They are not often found in products costing <US$1000.
DirectDrive® equals a direct signal path which means less signal degradation. This direct signal path is unequalled in audio and is the reason why the sound is so ‘true’.

Specs

In/Out
Digital Inputs		USB 3.0 type A “OTG” Socket (USB2.0 compatible/with iPurifier® technology built-in) S/PDIF (3.5m coaxial/optical)
Output		Balanced: 4.4mm SE: 6.3mm/RCA
DAC
DAC		Bit-Perfect DSD & DXD, PCM DAC by Dual-core Burr Brown
Clock		Ultra low jitter GMT Femtosecond Clock
Formats		DSD512/256/128/64, Octa/Quad/Double/Single-Speed DSD, DXD (768/705.6/384/352.8kHz), Double/Single-Speed DXD PCM (768/705.6/384/352.8/192/176.4/96/88.2/48/44.1kHz) MQA
Filters
DSD		Extreme/Extended/Standard Bandwidth
PCM		Bit-Perfect/Minimum-Phase/Standard
DXD		Bit-Perfect Processing
Line Output
Dynamic Range (Line)		>117db(A)
THD & N (0dBFS Line)		<0.003%
Output Voltage (Line)		>2V
Output Impedance		<240Ω
Jitter (correlated)		Below AP2 test set limit
Headphone Power Output
Turbo Mode	Power (max)	10.0V/4,100 mW
	Power (continuous)	>1,560 mW @ 64 Ohm >166 mW @ 600 Ohm
Normal mode	Power (max)	5.5V/1,900 mW
	Power (continuous)	>100 mW @ 300 Ohm >950 mW @ 32 Ohm
Eco mode	Power (max)	2.0V/500 mW @ 8 Ohm
	Power (continuous)	>250 mW @ 16 Ohm
Dynamic Range (HP)		>115dB(A) (Eco Mode, 2V Out)
THD &N (HP 500mW/16R)		< 0.008%
Output Voltage (HP)		>10V (Turbo Mode)
Output Impedance		<1Ω (iEMatch not engaged)
Maximum Output Power		4,100 mW @ 16 Ohm Load
Continuous Output Power		1,000 mW @ 64 Ohm Load
Spec
Battery		Lithium-polymer 4800mAh
Power System		Charging via USB-C, BC V1.2 compliant up to1500mA charging current
Dimensions		172 x 67 x 27 mm 6.8" x 2.6" x 1.1"
Weight		295 g (0.65 Ibs)