Red Wine Audio RWAK100 – Ampless

Disclaimer: Vinnie of Red Wine Audio modded my AK100 free of charge for the purposes of this review.

In Japan, a used Leica M8 fetches nearly double what it fetches abroad. Ditto Mont Blanc pens. In general, luxury items keep their mojo. Sadly, the opposite is true of audio gear. If you ever try selling an old headphone, or speaker, you’ll quickly realise that Japan is a buyer’s market.

About a year ago, I picked up two nine month-old iRiver AK100 digital audio players. The total for the two was 800$. Today, single units go for as little as 250$, mint. Of course, the AK100 isn’t the most impressive-sounding device out there. But it has a relatively stable interface, it takes two micro SD cards, it spits optical out (and in); and it works as a USB DAC for your computer. Its soul is the excellent, and warm Wolfson WM8740 24-bit DAC.

Add another 250$ for an Red Wine Audio RWAK100 mod, and your AK100 becomes a formidable audio player. If you’re lucky, the entire thing can be had for 500$.

If you want to know more about the AK100, check out Mike’s review. If you dig its form factor, but not its sub-standard headphone output, and want to keep using it without an amp, you have a number of options. The two best are Red Wine Audio’s RWAK100 mod, and the Mezzo Hifi MSAK100 modification, about which I sang a fortnight ago.

What is the RWAK100?

Vinnie from Red Wine Audio performs an oft-copied operation: bypassing the inexplicably 22 Ω resistor which buggers the output. The headphone output FETs are burned directly to the headphone jack. It’s a clean process that goes a long way to correcting the AK100’s most egregious audible errors. Finally, Vinnie slaps its ass with a cute branded Red Wine Audio bumper. The modification goes for 250$, which in 2014 dollars is practically nothing. Shipping is extra.

The modification reaps benefits far beyond the MKII AK100, which inexplicably debuted months after the AK100 hit market at the end of 2012. In fact, if you have a MKII AK100, I recommend having it modded by Vinnie – that is, if you want every last drop of performance.

Turn around time is weeks, not months. And Vinnie’s work is excellent.


I’m afraid of being too short in this section. You see, Vinnie’s mod doesn’t suddenly drop the WM7840 from to software mode as does Mezzo Hifi’s mod. And it doesn’t add functionality — that is, unless you consider a much better-performing headphone output a feature.

What it does do is fix the faulty hardware interface that held back the AK100. The RWAK100 is able to drive your favorite earphones and portable headphones with a minimum of distortion and other audible artefacts.

In particular, it completely eliminates audible drops in, or spikes of, bass, high mids, and highs. As long as your headphones don’t require endless voltage, Vinnies mod eliminates the need for an external amplifier. In fact, few downstream amps will be able to match the output performance of the RWAK100. Harmonic distortion, and IMD largely are kept in check. Stereo integrity, which stock AK100 players drop by 30dB, is kept very close to unloaded levels. In short: you won’t miss a single detail.

The WM8740 is a pretty mean DAC. It carries that famous Wolfson warmth without turning signal to muck, or sacrificing detail. And the RWA mod doesn’t squeeze your music through a low pass filter. In some ways, the RWAK100 produces a more energetic, unapologetic sound than the MSAK100 mod.

No more mid-volume IMD crackle or buzz. No more audible bass suck outs, no more dives in stereo performance. If you dig the sound of the WM8740, you’ll love the RWAK100. I’m floored. Stock AK100s are unable to supply enough current to earphones with violent low-Ω impedance swings. Pre-mod, my AK100 dropped bass output by 4dB against an energetic upheaval of treble from 5kHz – 9kHz. Another one busted up around 1,5kHz.

You can get used to anything. The water in our housing development smells like rotten eggs. It’s not safe to drink. It’s one of the wonders of living in a culture whose federal government has little say in the goings on of its provinces. And just as there are no standards to which DAP manufacturers are held, it is possible to get used to the stinky output of the AK100. Eventually you’ll be on the train, banging your head to John Denver, or Joy Division; next to you, noses will turn away. Your clothes stink like Old Faithful. And, to be honest, the music you’re banging your head to is tantamount to the quality of a 2005 iPod nano.

But a good RWA mod (or maybe yet another water filter, digging another 50 meters, or a move to Quebec) replaces the bad performance of your AK100 with awesome. And your eyes will open.

This article continues after the jump:

4/5 - (2 votes)

Back before he became the main photographer for bunches of audio magazines and stuff, Nathan was fiddling with pretty cool audio gear all day long at TouchMyApps. He loves Depeche Mode, trance, colonial hip-hop, and raisins. Sometimes, he gets to listening. Sometimes, he gets to shooting. Usually he's got a smile on his face. Always, he's got a whisky in his prehensile grip.


  • Reply November 25, 2014


    I also have two of the AK100. One modified by Vinnie and the other stock. The RWAK100 is used standalone and the stock one is used with a Vorzuge Pure II. Love the form factor of the AK100 and the two MicroSDXC slots. I use the RWAK100 as much as my AK120 II and AK240.

    • Reply November 25, 2014

      ohm image

      Yes, the AK100 has a GREAT format. I hope that it isn’t forgotten as DAPs get ridiculously large.

      • Reply May 12, 2015


        How would you compare the rwak100 to the stock ak120? these are the two I’m interested in to buy as my first DAP’s also thinking about the DX90 with the rockbox mod, but the AK’s would have my preference. thanks!

    • Reply November 26, 2014


      If I may ask how’s the sound between rwak100 and stock with vorzuge pure II?

      • Reply November 26, 2014


        Haven’t done any head-to-head comparison yet. I use the RWAK with IEMs and the AK100/Pure II stack with headphones (up to 600 Ohms).

      • Reply November 3, 2015

        ohm image

        Late, sorry: If you’re using an outboard amplifier the sound should be exactly the same. The modification really only affects the AK100’s ability to sustain signal under load (earphones directly plugged into its headphone output).

  • Reply November 26, 2014


    Hi there,

    To use with a K10, which AK100 mod do you like better, the RWA or the MS?


    • Reply November 27, 2014

      ohm image

      It all comes down to this: background hiss. The K10 is very sensitive, but not overly high-peaked, so it can withstand a bit of hiss. If you have to have absolutely black backgrounds, the only DAP on the market that does it is the MSAK100. If you want the best quality sound, the RWAK100 is phenomenal and lacks the hardware filters that change the sound as in the MSAK100.

      I’m torn. For 250$, the RWAK100 is a steal. Add 500-600$ and you can have the MSAK100, which is also phenomenal, but if you don’t want the balanced output, and if you aren’t bothered by the hiss, the RWAK100 is _the_ choice.

      I’d plug your K10 into a stock AK100 to see if you can deal with the hiss. If you can, then RWAK100 is the most economical choice. It is also a great performer.

      • Reply November 27, 2014


        Mmm, so you think that the best sound quality comes from the rwak100 but with some hiss?
        Last question: have you tried the AK100II by any chance? If so, how does it compare to the ak100 mods?

        Thanks a lot for your help!

        • Reply November 27, 2014

          ohm image

          I wasn’t clear, sorry. _Both_ the RWAK100 and the MSAK100 provide excellent sound. The MSAK100 is overall better (less hiss), but has a hardware filter that rolls off the highs. If that is your thing, it is the best. If you like the stock AK100 sound unloaded, the RWAK100 is the better option, but the AK100 still will hiss.

          I’ve tried the AK100II briefly but under meet conditions. It seems a very nice device, but it is double the size, and more expensive. And, its output can’t hold a candle to the MSAK100 and is not clearly superior in anything other than processing power, to the AK100.

          If you are going to spend a bit more than 1000$, the MSAK100 is it. If you want to spend less and get tip top performance and SQ, whilst saving a lot of money for things that really matter (earphones or headphones), the RWAK100 is your best bet.

          • Reply November 27, 2014


            Got it!


  • Reply December 11, 2014


    Hi Nathan,

    I’m in the market for a new DAP and I’m trying to decide between the RWAK100 and the DX90. I would mainly be using them with a pair of SD-2s, which are fairly sensitive. Do you think you could offer a more detailed comparison between the sound of the two units?

    Thanks in advance.

    • Reply December 18, 2014

      ohm image

      I’ll try to answer this in a follow up to this review. I’m sorry this is late. I hope you can wait just a bit longer. Personally, size always trumps overall feature lists for me, but the RWAK100 is every bit as feature complete as is the DX90.

      • Reply December 19, 2014


        Hi Nathan,

        I decided to pull the trigger on the DX90 because most of the reviews I could find say that the A&K player has a warmer tonality and I would rather have a more neutral sound like the DX90’s. Still look forward to hearing your thoughts though.

        • Reply August 4, 2015

          ohm image

          Late as usual: yes, the DX90 is more neutral than the AK100. If that is what you value, hit it up (I assume you already did). If a bit of warmth is your thing, a modded AK100 is great.

  • Reply February 6, 2015


    Hi Nathan,

    In fact, i’m a little lost…

    I read in July 2013 on this website (Mike) :
    AK100 Mk2
    Aside from some funky Svarovsky edition AK120 and different colored
    AK100s, they also had the AK100Mk2 with the 1 ohm output impedance. BIG
    sound improvements. Very clear, improved bass clarity, lower bass
    extension. I think it’s even better than the modded AK100s I’ve heard.

    I read your two articles about mods on AK100…
    And you find them better than AK100 mk2.
    Is that correct ?

    Obviously, you don’t agree with Mike…

    So… After reading everything, i feel… lost… 🙂

    Have you ever talk about this with Mike ?

    Thank you,

    • Reply March 23, 2015

      ohm image

      I’m very late, sorry.

      The MSAK100 uses a different DAC, is completely noiseless, and has balanced output. Mike hasn’t tried it. As for the MK2, it has 3Ω, not 1Ω output. Red Wine Audio’s mod is higher spec than the MK2, especially for earphone usage.

      It is brilliant. I have not chatted with Mike about it.

  • Reply December 11, 2016

    Alex Alanis

    Hi, if you had to choose between making the mod or getting a Plenue D?

    Which option you’ll choose?


    • Reply January 17, 2017

      ohm image

      Well, the Plenue D is cheaper. And it sounds good. The mod measures better, but hisses more. If you’re going to use outbound amps, the RWA mod is far better. Trade offs.

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