General Information


iFi audio Pro iDSD Signature takes the original Pro iDSD and pushes it even further towards perfection. Over its predecessor it features:

-Sonically darker background and a punchier bass
-Upgraded power -supply components to lower the overall system noise by 300%
-Precisely matched NOS GE5670s tubes
-Added support for USB1.0 (PS4/PS5)
-A new aluminium remote control
-A top-of the range iPower Elite power supply included

Latest reviews


Headphoneus Supremus
iFi Pro iDSD Signature - Full Review
Pros: All in one nature - Executed very well
Higher performance than original model
Cons: Fairly expensive
Build quality could be more "premium" feeling

Hi Guys,

Today we are taking a look at iFi Audio’s recently released update to their flagship all in one DAC/Amp, the Pro iDSD Signature. For the rest of this review, I will refer to it as the iDSD Sig.

I reviewed the original Pro iDSD about two years ago, and really did quite enjoy it, and all the capabilities it contained. The new signature model is honestly not that different in terms of features, being more of a refinement of the overall concept, rather than a brand new product. In this sense, the new signature model feels like the obvious conclusion of this iteration of the iDSD concept. Compared to the original model, the small improvements here and there all add up to a product that feels more mature, more complete, as well as fixing little things that may have been left on the table with the original model. I would recommend reading my original review, as I think this could be considered as a long addendum to that review, rather than a stand alone review of a new product.

In terms of looks, the iDSD Sig is actually the same. It features the same chassis, and features, with the only difference being a golden “signature” badge underneath display, and golden surrounds of the two main knobs on the front of the unit. These little bits of sparkle are actually totally welcome, and do give the product a little bit more intrigue in terms of looks. Don’t expect a massive difference though, as it is still largely the same original silver chassis in terms of size and shape.

Funnily enough, this actually reflects the sonic changes for the new iDSD Sig also. The overall tonal balance is pretty much exactly the same I have found, but some key upgrades in terms of parts quality etc…have brought an increase to the technical performance of the unit. The changes are all incremental improvements vs. an entirely different sounding device.


iPower ELITE

The first thing you will notice when unboxing the new iDSD Sig is the included iPower ELITE power supply which comes standard with the Signature edition. It is a hefty unit, being very well made, and feels great. I did try doing some switching between a generic cheap power supply unit, and the included ELITE version, and found that it brought a sense of a blacker background, which does help with perceived detail and space. It is not a huge difference, but as the ELITE unit is included stock, I think it is a welcome addition, and does bring some improvements to the overall sonic performance of the iDSD.


iPower ELITE

The tonal balance of the iDSD is again largely similar to its predecessor. There is a slight warmth to the sound, and I certainly wouldn’t say the iDSD Sig is a cold sounding device. Similar to the previous model, the iDSD Sig features three modes of operation. Solid state, Tube, and Tube+. I largely settled on using the Tube mode as my favourite, but they do all have slightly different signatures. The Solid State mode is the most incisive, with a faster sound and sharper edges to the notes. The Tube mode slightly rounds off the leading edges of notes, and adds a very slight hint of harmonic richness that isn’t there in solid state mode. To be honest, the difference is very small between the two modes, which is why I ended up preferring the Tube mode. Tube+ does take it slightly more to the more relaxed and rounded off side of things, which ended up not being my overall preference. The Pro series ability to switch between all three modes is still a unique feature, and really does add to the “Swiss Army Knife” nature of the series. You can switch between modes depending on your headphones or speakers used, and also your mood and listening tastes.

I remember that with the original iDSD I mainly used the Bit Perfect + mode, but after more time with the iDSD Sig unit, I ended up using iFi’s GTO filter. “Gibbs Transient Optimized.” I did do a lot of back and forth between the modes, but the GTO filter did seem to be the most incisive, “correct,” and overall, the most refined sounding filter. I’m not sure why I ended up preferring it over the Bit Perfect + mode I used on the original model, perhaps my hearing preferences have changed over time. Regardless, I would recommend experimenting with all the various filters and options, to see what works best for you and your ears. The iDSD Sig also features DSD512 and DSD1024 upsampling just like the original did. As with the original, I didn’t find these made massive differences, but the DSD1024 upsampling was worth trying. I found I preferred it for electronic music, and fast paced heavy metal and similar. Again, it’s something worth experimenting with, as everyone is different, and you may end up preferring your music without the DSD upsampling.



The iDSD Sig is an all in one unit, just as its predecessor was. The headphone amp does have slightly more power (4200mw vs. 4000mw) from the balanced output. Also included is the 4.4mm balanced pentaconn output, vs the originals 2.5mm output (though after some time the original model did include the 4.4mm output also.) This is a welcome addition, as it is just a better, more sturdy option compared to the 2.5mm balanced jack. With 0db, 9db, and 18db gain option, the pro iDSD can drive most headphone on the market. For me, it reaches its limit with the AB1266 TC from Abyss, and I wouldn’t recommend it for the Susvara or HE6seV2 (or similarly hard to drive headphones.) Although the headphone amp is not the most competent on the market, I think it has to be taken into consideration that this is a small, and compact all in one. In that context, it is actually a very good performer, at an attractive price (again, in terms of an AIO.) The Pro iCAN Sig obviously exists for a reason, and I would recommend it for someone who wants a dedicated headphone amplifier with higher performance than the iDSD’s all in one nature. With that being said, if you are a more casual user, or perhaps you mostly listen to speakers using the iDSD as your DAC, and want to use headphones at night when its quiet, the iDSD Sig absolutely has you covered. You can also use very sensitive IEMs with the iDSD Sig from the 3.5mm output, which has iFi’s “IEMatch” feature, to help reduce any hiss.

The overall technical performance of the iDSD Sig seems to be where most of the improvements are, vs a change in its overall tonality etc…While the ELITE power supply helping bring about a blacker background with more perceived detail, things like improved capacitors etc…and tighter matching tolerances of the components seem to have lifted the iDSD Sig’s overall performance also. Again, it’s not a vastly different sounding unit to the original iDSD, it just sounds slightly more refined, more detailed, more spacious, and improved in an overall sense on the technical side of things.



The Pro iDSD Signature from iFi is a seriously great all in one unit, just as its predecessor was. It has taken the sound from the original model, and built upon it in a meaningful way. Although the sound in terms of tonal balance remains very similar, it has improved its technical performance, through better components and a much better power supply unit. It retains the awesome Swiss Army knife like capabilities of the original, and thankfully also retains the same size and almost transportable nature of the original also. I think for the right customer with the right needs, the iDSD Sig is hard to beat, as it simply covers so many areas in a competent manner. If you only need a pure DAC, and have more space whilst also wanting to keep your budget in check, you may be served by better dedicated DACs. However, for those who want a multi functionary device, tubes, DSD upsampling etc…there really isn’t a better option on the market for an all in one option.

I’m looking forward to what iFi comes up with next for their “Pro” range, but for now, the Signature iDSD and Signature iCAN certainly have people’s needs covered.
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