Disclaimer: Ryuzoh lent me his balanced-modded Mojo mod for two weeks. Its most basic modification, the addition of a balanced output, goes for 45.000¥; the full Monty, including internal transformer, goes for 74.000¥. Ryuzoh’s webpage is here: http://info.m-s-tech.jp. This is his Twitter handle: @ryuzoh_dx0xb. This is his email: firstname.lastname@example.org. He speaks great English, so hit him up (and maybe mention that old Nathan sent you).
Disclaimer II: Ryuzoh has offered to balanced mod my Mojo, [for a discount], I am impressed with his work.
Every project Ryuzoh has been involved in exhibits a basic character set: stability, performance, and with the notable exceptions of his mods, ugly mugs. FiQuest wasn’t pretty. Neither was the Cio MB DAC. Come to think of it, the AK240’s harsh angles are fit only for press photography; and Mojo… God, what a horrible, alien design. Of course, neither Mojo’s nor the AK240’s ugliness are Ryuzoh’s fault.
I will get more into what Ryuzoh did in a later article at ohm, and later this week I’ll faff about all of it at Headfonia. For the moment, I’ll just say this: Ryuzoh’s love for Mojo is what drove him to exchange a redundant single-ended jack for an AK-OKAY 2,5mm TRRS balanced jack. He also reduces gain in the balanced side by fourteen decibels. (Even reduced that much, his mod spits out more voltage than today’s most powerful DAPs.) As a result, Ryuzoh’s balanced mod won’t reach the same 120dB of dynamic range its single-ended side is capable of (unloaded). It tops out at about 115dB. If you’re pairing Mojo with an outboard amp (god help you find one good enough for Mojo) that can take in high-voltage signals, there’s small benefit to Ryuzoh’s mod. I am confident that no balanced amp currently on market provides any measurable benefit to Ryuzoh’s mod.
Ryuzoh’s also a sweet guy that sucks down caramel lattes; he also takes bespoke requests. His full Mojo Monty adds in a transformer [to the SPDIF circuitry] to reduce Mojo’s EMI and RF interference, particularly when paired with smartphones. (More on that later.)
I’m not big on balanced audio - neither for portable audio, nor for desktop. But I’m also not big on Mojo’s redundant jack. There is no way in hell that my wife will plug her Grado GR8s into the right hole while I plug mine into the left. Not only does she hate people-just-ain’t-no-good Nick Cave, she dislikes nubby outboard audio gear.
So, while I don’t fit Ryuzoh’s target market, I am put out by a wasted port. That, and, for ampless balanced use, Ryuzoh’s implementation is gold.
Single-ended I find little beyond placebo between them. As I mentioned in the Ryuzoh-modded AK240 article, there are a few things to keep in mind. Specifically, my ADC isn’t meant for measuring headphone outputs. And while it is capable of clocking Mojo (at IMD-limited volume levels) for dynamic range results of in excess of 120dB, the Lynx HILO isn’t an audio test bed. I note small variables between measurements of up to 0,5dB. I do my best to reduce measurement aberrations: re-calibrate sources, take control samples that I match against old measurements, and measure to the highest voltage/current stable volumes. I’m reasonably satisfied with the work I’ve done.
Unfortunately, I wasn’t able to absolutely match volumes between my Mojo and Ryuzoh’s mod. There’s about a half decibel between them. There is also about a decibel difference in the most recent measurements I took of my Mojo from the ones I took in November. Are iOS updates to blame? The latest iOS certainly improves the iPhone 4s (noted in my Headfonia article about the classic smartphone). Or, has Ryuzoh's mod also lowered absolute single-ended gain by -0,5dB?
I don't know.
As to Ryuzoh’s claim that the transformer reduces EMI and RF interference, oscillator tests may bear that out. My experience doesn’t. I’ve had to rely on listening tests (guilty). Hugging the back of my iPhone 6, at times both his and my Mojo tick tick tick with familiar wireless bugginess. [Ryuzoh has informed me that the transformer is installed only in the SPDIF circuit, which may be why I noticed the ticking sound. He intends to extend the mod to the USB circuitry, too.]
And, unless my ears are playing tricks on me, Ryuzoh’s mod hisses a hair more than my unit. But not all Mojos were created equal. The first unit I tried hissed worse than an original AK100. The second was better, but audibly echoed the music I was listening to from its chassis. Naturally, that unit I returned. My anecdotal experience (three units) informs me that no two Mojos are created equal.
The above aside, Ryuzoh’s mod completely shits all over both Onkyo’s DP-X1 and AK380 under load at each unit’s maximum stable volume. The results are ugly. The DP-X1 outputs 328x more THD and 128x more IMD at maximum stable volumes under the same load; at 4191x the THD and 3441x the IMD, and especially at its asking price and against its ultimate marketing, the AK380 deserves to be thrown from the tallest building, drowned it a year’s worth of rock-concert sludge, and then blue angeled to a fine powder before being sniffed by next-year’s juvenile delinquents. Even correcting for the 6dB in output, the AK380 still outputs 2000x more THD than Ryuzoh’s mod, while the DP-X1 gets away at about 100x. Dropping the AK380 to below the volume used by Ryuzoh’s mod yields significant drops in distortion. THD is now merely acceptably high. IMD still is insane. Put simply: the AK380’s balanced output is worthless for anything beyond tempting new cable purchases. Under load, the DP-X1’s output isn’t that much better. Both edge out the Mojo’s dynamic range and SNR at stereo crosstalk-stable maximum volumes.
Gullible or not, audiophiles deserve better. Until Ryuzoh’s mod, the best audiophiles could have hoped for was the DP-X1, which, unloaded, is nearly faultless. But if you’re keen on skipping zealously high levels of THD and IMD, you really need to hook it to a Vorzüge PURE II or something. Stock, a loaded Mojo performs well better. Rzyuzoh modded, balanced, and loaded, it isn’t just in a different league, it plays by different rules.
The following Rightmark Audio Analyzer tests were conducted through this equipment.
Transport: Apple iPhone 6
Source: Chord Mojo (Ryuzoh mod)
ADC: Lynx Studio HILO LT-TB
Computer: 2012 27" iMac
Cables: 1,5m Hosa Pro 3,5mm stereo to dual 3-pin XLR (around 8$); bespoke y-split 2,5 TRRS to dual 3-pin XLR made by Musashi Sound Technology.
NL - no load
SM2 - Earsonics SM2
ES7 - Audio Technica ES7
NOTE: I decided to not publish scores for the DT880/600Ω because the headphone presents almost no load to the Mojo. That, and mine’s not balanced.
24-bit TARGETS and loads (+6dB)
VS Onkyo DP-X1 and AK380 24-bit balanced loads (+6dB)
Stunning, but still an outboard audio device. If you’re really into performance and even more interested in balanced portable or desktop audio, you’ll have a hell of time (as in you’ll kill yourself) trying to better Ryuzoh’s mod.