Disclaimer: This bad boy is from Amazon.jp. The MD-DR7 was Sharp’s first 1-Bit branded MD portable recorder. It was also the first mass-marketed portable audio product with a true balanced headphone output. Eat your heart out, Astell & Kern, HiFiman, and the like. The DR7 uses the same TRRS pinout as a modern Astell & Kern, but in 3,5mm rather than 2,5mm form. So, if you have a pair of AK-compatible balanced headphones, all you need is a step up (2,5mm - 3,5mm) adapter and you’re gold. The DR7 has a low noise floor, high DR, and for its time, a powerful headphone amp. If you’re interested, check out Minidisc.org’s page on it: Sharp MD-DR7.
From late 2002 until around 2004 headlines among the MD faithful were awash with an age-old war. The perennial battle between Sony and Sharp over ATRAC and dominance over the minidisc scene was in its final heat (as was the format). In a gambit to remain relevant, Sharp and Sony lead insane marketing campaigns which promised the world from their respective flagship MD products. If you were in the Sharp camp, Sony sounded bad. If you were in the Sony camp, Sharp sounded bad. But gosh, how wrong one camp was.
RMAA and review: Sony MZ-EH1 24-bit
Minidisc VLOG - 07: Sony MZ-RH1 Review
Minidisc VLOG - 05: Sony MZ-NH3D
RMAA and review: Sony MZ-DH10P 16-bit
RMAA: Sony MZ-RH1 16-bit
RMAA: Sony MZ-NH3D 16-bit
RMAA: Sony MZ-B100 16-bit
RMAA: Panasonic SJ-MJ500 16-bit
RMAA: Kenwood DMC-S55 16-bit
RMAA: Sony MZ-E55 16-bit
RMAA: Sharp MD-DS8/9 16-bit
It was a simpler time. Balanced output was an old thing, but to the mass market world, it was opaque. Sharp’s own marketing literature was confusing, full of lies, and self-contradictory. There were two basic ideas behind 1-Bit: that you’d get back sound lost from compression, not to mention the greater resolution from a 24-bit ATRAC encoder. The two would work in tandem, revealing dimples were previously there had been just notches. Finally, the balanced output would reveal greater stereo nuances and separation. The first was probably a hand-me-down from SACD marketing. Worse, it was complete bunk made because marketers knew that audiophiles were idiots. The latter was true- but from a point of view that relied on an inconvenient truth.
We’ll get back to that.
What I love about the DR7 is that it hailed back to the pre-MZ-R55 days. Sony bodies wore thick aluminium sheet, opened and closed on solid hinges, and bore large and often grippy battery compartments. Their cases didn’t flex, and in general they were ready to be thrown around. After the MZ-R55, they were delicate, flexy, and needed the kiddy gloves. The DR7 on the other hand felt like a miniature MZ-R50: it showed little flex, and its aluminium sheets were moulded into strength-boosting shapes. Gosh, it feels great in the hand. It feels ready for the long haut. Its hinges are solid and perfectly aligned, and its battery compartments house more solid grounding structures that better weather the vicissitudes of age.
And boy did the DR7 sound different to a Sony of the same age. 1: it didn’t have a baked-in bass boost. 2: in its day, it was hissless; even today, you’ll be hard put to find an earphone that reveals unwanted noise from its outputs. (Hell, it’s almost on par with a Cowon Plenue D2 or Onkyo DP-S1, both hissless benchmarks in my office.) 3: it gets louder than an iPhone SE and holds up to monster 2nd and 3rd-gen MD units. For an MD of its vintage to rival its enormous forebears as miraculous. In fact, its amp is so powerful that if the MD format were higher spec, I’m sure it could spit signals rivalling lower theoretical dithered 16-bit ceilings. 4: ~97dB of dynamic range and signal to noise ratio from a portable Minidisc unit? That’s something isn’t it? If you want that from a Sony, you’ll have to pony up for the rare and now Uber-expensive Hi-MD Sony MZ-EH1, Sony NH3D, or like.
Unfortunately, the DR7’s downsides quickly pile up. Its remote bristled with so many buttons that picking it up without accidentally pressing a button was almost impossible. Its relatively high levels of jitter bordered the audible. Worst of all: the DR7 had basically no stereo image of any kind. It was practically monaural. The best in the 1-Bit portable class gets less than 30dB of separation. Most get below 25. Keep in mind that the stereo separation target for 16-bit audio is almost 100dB. Under load most MD units crank out signals between 50 and decibels. In geometric terms, the DR7 showed half the resolution of the worst MD units out there. Next to the best, it was pitiful. Next to any modern DAP and its stereo image sounds like two repeated left or right channels.
The only way to get any stereo from an Auvi unit in the day was to use the (admittedly good) stock Sharp-branded Sennheier MX300-style earbuds or the horrible after-market clip-on (also from Sharp). These earbuds were wired to utilise the DR7’s balanced output. Sharp bundling them in was a good idea. They sounded far better than the horrible ear buds that came with Panasonic and Sony units. For this reason, the Auvi players sounded great. But if you wanted to upgrade from them to something upscale from Sure or Etymotic, you’d lose almost all stereo detail from all of your music.
Today, step-up (2,5mm to 3,5mm) TRRS adapters are easy to find. Plug one in and Voila! 24dB of left/right separation becomes almost a guaranteed 80dB- and that’s a lot. Again, though, at ~80dB, you’re getting the equivalent of what a high-quality Sony of its day got without the horrible marketing and hardware lock-in that limited you to Sharp’s two rebranded Auvi earphones. The other problem is that the DR7’s internal amp didn’t output enough current to keep frequency responses flat and IMD low. Jitter levels are high, and suckouts in the high mids and vocal bands dive almost 5dB against controls. That, coupled with the whole no-stereo problem are big provisos/pills to swallow.
On the plus side, the DR7’s bass boost engine was great and, while current-limited, its sound was sparkly and punchy. Sure, better bass boosts (Aiwa AM-F70) exist, but if you use the included buds, the DR7 really did sound good. It’s just if you wanted to use better headphones, or even connect to a downstream stereo amp, you got de-facto monaural sound.
Had Sharp merely improved the amp from its predecessor, the DR7 would have been gold. Alas, Sharp ‘fixed’ what wasn’t broke. Being ignoramuses, audiophiles ate it up, and the DR7 is still remembered as a giant of sound quality. There are pages and pages on various internet fora detailing how much better and more stereo nuanced the DR7 sounded compared to the Sonys of its day. It’s just an opinion, right? I guess so. But if your opinion turns into evangelism and that evangelism turns into many people forking over hundreds of dollars for gear that doesn’t do what they were told it did, a great sin has been committed. In this case, Sharp’s marketing beat everyone’s ears. If you hear stereo differentiation from the DR7 through non-Sharp earphones, you’ve bought the entire marketing angle, hook, line, and sinker.
Source: Sony MZ-EH1 portable Hi-MD player
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
Parterre - FitEar Parterre
ES7 - Audio Technica ES7
DT880 - Beyerdynamic DT880/600
NOTE: My two-prong Linum balanced cable bit it this week, rendering all tests loaded with the Earsonics SM2 unreliable. For this reason I added the FitEar Parterre - for which I have a balanced cable in good repair - to the mix. I like Parterre. I won’t add it to my test suite because I don’t want to break it. But I had no other choice.
16-bit VOL (Full) @+0dB - all targets (single ended)
16-bit VOL (Full) @+0dB - all targets (balanced)
I say a lot of bad words about the MD-DR7, but I love it. It is solid, easy to use, and has great battery. It doesn’t hiss, and, in its own way, it is handsome. But it doesn’t really sound good unless you limit it to a very narrow band of headphones that won’t swamp its high-Ω output.