Disclaimer: I have recently reviewed the Ikko Oh-1 and purchased the Oh-10 based on my enjoyment of the Oh-1. I was approached by Ikko regarding reviewing the new Zerda DAC/Dongle and was sent one of each type for purposes of review. I do not have any financial interest in Ikko and am just a customer. R 9/4.
The Zerda comes in an attractive box with a flip up front face magnetically held in place. Packaging for the two models is identical save for the black triangle in the lower left that identifies the connector type. I say this as the reverse has the specs and a picture of the product. The picture displays the USB-C connector regardless of which type is contained within it. Check either the black triangle on the front left or the words under the UPC code on the reverse to be certain you are getting the type you need for your phone/tablet/computer. lifting the cover reveals the dongle housed in a foam surround. The box is solid enough to use for storage when not in use.
The Zerda uses an aluminum alloy shell and matching connector housing anodized to match the color of the OH-1. The Zerda can be had with either a male USB-C or Apple lightning connector for allowing a wide range of potential host devices. At the opposite end, a 3.5mm TRS / Mini-Toslink Jack provides the output. The input connector housing is flat while the output end is a stretched diamond shape with a larger horizontal and shorter vertical dimension. It is nice to see a proper strain relief at both the exit point of the input connector and the entrance of the output connector housing.the cable between is roughly 3 inches in length and is fairly soft and pliable. Ikko is quick to point out that the housing is fully shielded to help minimize interference from phone signals or wireless devices and even uses shielded silver-plated Oxygen free copper cabling to further isolate the device. All this in a package that weighs less than half an ounce.
The Zerda uses Cirrus Logic’s CS43198 Dac chip to do the heavy lifting. This is the same dac used in the Opus#1S and the A&K SR15 which put puts it in pretty good company. Obviously there are other differences in the three devices, but one you might not expect is that the Zerda is the only one of the three to support Optical output. Thats right, the output port on the Zerda can be used as a 3.5mm analog headphone out or as a mini-toslink output to an external device. I tried the optical out, using the output of the Zerda to the optical input on both the iFi xDSD, and the new Xduoo XD-05+ and it worked swimmingly well with both. I did find that some phones (Motorola) struggled with getting the optical to work while others (Samsung) worked from the get go. Optical output from an I-pad (Gen5) also worked fine. The Zerda does have Apple MFI certification so should work across pretty much all the I-device eco-system.
The limits of resolution on the Zerda depend on the file type and output type being used. For standard PCM files output to a headphone, the DAC supports 32/384 while the fiber optic output is limited to 32/192 and DSD is limited to 128 regardless of output type being used.
I’ll admit going in that I had high expectations of this little DAC based on previous experience with both the chip at the heart of it (Opus#1S) and with Ikko. That may mean that I was a bit harsher on it than I normally am as I know what magic the 43198 can hold and wanted to see it on full display here.
The signature is fairly neutral with a slight push in the mid-bass that gives it a touch of warmth and another very slight push in the upper-mids/lower treble that move vocals a bit forward. Neither of those regions that are pushed forward are anywhere near as pronounced as some competitors models (more on that in a minute). Bass is good with adequate texture and depth, mids are well rendered if just a touch soft for strings (I’ve found this to be true of some other 4398 and 43198 implementations so this may be inherent to the chip). Top end is quite good both in detail and in extension and while there is a slight push in the lower treble, overall linearity is quite good and very little sticks out in front of anything else. Detail is quite good overall, but a bit better in the mids and upper range than in the low end, but bass texture is acceptable if not spectacular. I think this is likely a limit of the power available for these little DACs to work with as it seems an almost universal truth that the bass is not overly well textured or detailed across the entire range of dongles I have tested.
Soundstage, well guess what, soundstage is so dependent on which headphone you use that I’m not sure I can attribute any of what I heard to the DAC. This is a good thing as the DAC is supposed to be transparent, but at the same time will frustrate some readers who think I should make comment. Headphones that typically have great stage still do when listened to through the Zerda, those that typically do not have impressive stages are still unimpressive. Spatial cues are well rendered and seating the orchestra was a fairly straight forward task with several different headphones I tried.
Power is quite good for a dongle, but is still realistically limited to headphones at or below 150Ω. The surprise pairing of the tests was the Sennheiser HD700 which performed beautifully when combined with the little DAC. The worst performer of the day was a tie between the 600Ω Beyer, and the Fostex T50rp with the sensitivity of a slab of concrete. Both simply over-match this little guy and are not good choices. I also paired the Zerda with both of Ikko’s in-ears and no surprise here, they both have excellent results and allow the in-ears to show their individual personalities.
Hidizs Sonata S3 – I found the Zerda to be a bit cleaner sounding and linear than the S3 and also a bit more potent as the S3 began struggling with headphones much over 50Ω while the Zerda had no trouble until up past 150Ω. Build quality is a bit better on the Zerda as the anodized aluminum shell looks more polished and less industrial than the housing on the Sonata. For me the Zerda is a clear winner with better sound and more power as I simply didn’t find the Sonata enough better than the $10 apple dongle to warrant the extra cost. Not so with the Zerda.
VE Odyssey HD – Again, very similar stylistically. The Odyssey HD build quality is not up to the Zerda, but its sound is coming closer. The Odyssey HD is slightly more linear as it doesn’t have the mid-bass push but still shares a bit of upper-mid/lower treble bump for vocals. The trade off is in power and bit rate as the Odyssey cant match the top end of the Zerda in either category. So we have slightly better linearity on one side, and more detail and better power on the other. I can adjust the linearity with EQ, but it is pretty hard to add missing details or power so for me the nod goes to the Zerda.
Hifime Tiny Type-C – Hifime makes a lot of budget friendly products and the Tiny is one of those at $29.99 when in stock as it seems to perpetually be out of stock of late. Obviously the price is a plus for the Tiny, but the build quality is not a match for the Zerda with plastic case vs aluminum and the cable quality is improved on the Zerda as well. Add to that the fact that the Tiny tops out at 48kHz while the Zerda does at 384kHz and you have a quite a disparity. The Zerda just plain sounds significantly more detailed and cleaner when A/B vs the Tiny. Honestly, it isn’t worth the savings as the Tiny again isnt a substantial improvement on what is shipping with most phones today. Zerda wins easily.
Moving up a bit in price from those, and into a larger form factor we have the Audirect Beam. At double the price of the Zerda, is it double the DAC? The Beam does have several things going for it, it offers DSD decoding up to and including 256 while the Zerda stops at 128, it has on device controls for volume and play/pause where the Zerda relies on the software to control those functions, and it has sound quality and power to match the Zerda. What it also has is considerably more bulk and the tendency for the connector cables to dislodge when carried in a pocket. The Beam is best kept in hand as the detachable cables are easily knocked loose if jostled. It was not uncommon during my tests to see “USB DAC disconnected” when I looked down at my phone to figure out why my music had stopped. Also while my personal Beam has been solid, reports of build issues are common enough that I have some concern about long term durability. This is a much closer fight, but when you figure most people will pair it with one or the other connector anyway and wont need the other, it makes the Zerda an easy choice as it doesn’t have the cable issues of the Beam.
Then we have the high end of the market. Having recently reviewed the Dragonfly Cobalt, I can’t resist throwing it into the mix to see if spending that much more really gets you that much more. For starters, the Dragonfly is limited to 24/192 so the Zerda has a resolution edge on it. Sound quality is honestly roughly the same although I will give the Cobalt a nod for being a little more crisp while the Zerda is a bit smoother and more forgiving. Build quality is better on the Zerda as the Dragonfly actually rocks inside the plastic shell and had considerable play. So better build on the $99 Zerda than on the $300 Dragonfly with very similar sound quality. Oh and did I mention the Zerda has optical out? Unless you just have to have MQA support, save the money and grab the Zerda.
Pros: Fantastic build quality, good detail level and nearly linear signature
Cons: limited power, slight bump in mid-bass and upper-mids/lower treble.