The Awesome: ALO Studio Six


Sometimes a product is so awesome I really can’t wait to sit down and start writing my thoughts on it. The ALO Studio Six is one of those products. 11:37PM at night and I decided to open my computer and start jotting down the thoughts I’ve gathered from my listening sessions with the Studio Six. Maybe I’m slightly exhausted from a long day as my fingers seemed to be a bit stiff with the keyboard but still I decided to go on. After that first draft, weeks passed by as I did other reviews while at the same time still compiling words in my head, as there are moments when I discovered a new phrase that I thought is fitting to describe the Six.

For once, I wished that ALO wasn’t a sponsor of the website. They’re a great sponsor, but the fact that they are a sponsor sort of gets in the way of me writing a review on the Studio Six. I don’t want the things I have to say gets discounted because ALO is a sponsor, but that’s really the fact that I have to deal with. Unless ALO suddenly decides to stop their sponsorship after reading this review (I know they read my reviews).

Another factor is the Headfonia Store. I really have no hidden agenda when writing this, but I tell everyone that they have to read my reviews with a grain of salt if I happen to be selling the product in the store. We had a few enthusiasts in the store earlier today and they asked me about the Studio Six. My reply was, “Of course it’s great! I’m selling it!”. I did say that with a sarcastic remark as I added “And it’s the most expensive product in my store! Hell yeah it’s great!”. Everyone laughed and it was a nice light joke, but it outlines the fact that I’m stuck in this situation that really is not the best situation to be in as a reviewer.

Anyway, the amplifier is here and here is my review of it.



The amplifier arrived one Saturday many many weeks ago and I can’t tell you how excited I was to unbox it, despite the less than phenomenal, but safe, cardboard packaging. Huge, thousand dollar tube amps tend to arrive in a standard brown cardboard box with no fancy graphics. The box never needs to be fancy because you know for sure what’s hidden inside of it. Weeks of staring at pictures on the Internet has finally come to and end and now you finally get to see the product with your own eyes. Isn’t that the big reason to why we make sacrifices of our wallet?



The only thing you have to check is if the manufacturer adds plenty of paddings to make sure the amplifier survived international postal service. The tubes required for the amplifier were supplied: 1 6SN7, 2 6V6, 2 OB2, and 1 5AR4. Don’t worry if you can’t remember all the tube types at first. What matters is that you plug the tubes in their respective sockets, which by the way I appreciate how ALO used high quality teflon sockets for the Studio Six.





I quickly installed the tubes and hooked the Studio Six to the Audio-Gd Ref7.1 which is the 2nd best DAC we have at the store (the Ayon Skylla II is a bit too tubey for my taste). I hooked up the Audez’e LCD-3, knowing that ALO amps have always been good companion to Audez’e’s headphones, and I had a listen. It was nothing like what I had expected. I was expecting a huge 300B like soundstage and with an excellent depth in the sound. I was expecting a super-turbo-charged PanAm or International sound (those two are my favourite ALO amps). But I was getting none of those. The sound that I got was full bodied, punchy, impactful, and clean. A bit similar to the RX MK-3, but a few leagues up in terms of dynamics and refinement. Not quite the flagship tube-amp-sound that I had expected with their wonderfully huge soundstage and depth. I had expected a darker, slower, more spacious sound but of course I forgot that those characteristics are often associated with big tubes like the 300B, 45 and 2A3 upon which flagship amps are usually based on. Amps with the 6V6, on the other hand, tend to be faster paced, more aggressive, more forward, more attack and that’s what the Six is all about. It’s reminisent of the Apex Peak but with a much higher level of dynamics and bass slam. It’s also somewhat like the Manley Stingray integrated amp with the EL84 tubes but the Six is far cleaner in sound and again a much stronger dynamics; at least for headphones.

The dynamics were staggering and easily miles ahead of any other headphone amp I’ve heard, even solid state ones, but I was yearning for more depth. It was hooked on to the Ref7.1 DAC which is #2 on my list of super-spacious DACs. Surely the amplifier can do better than this?

That night after I left the store, the sound of the six kept on ringing in my head. The dynamics of the amp lingered on my mind. It’s like the other week when I discovered this great coffee bean (a house blend) and somehow the taste of it kept on lingering, and I couldn’t wait to have another cup the next morning. The day was Saturday and the store was closed on Sunday. I thought about going to the store on Sunday just to have a listen to the six again, but time didn’t permit me that Sunday and so I was very enthusiastic to go to the store on Monday and listen to the six again.

Apparently some folks wanted to try out the amplifier on Saturday and so the amplifier was kept running the whole day on Saturday. On monday when I listened to the amplifier, the sound opened up quite a bit and I heard a good amount of space being opened up thanks to the run in time on Saturday. Top and bottom extension which I felt had a slightly abrupt cut off on Saturday was now smooth and well extended. Over the next few days I kept on listening to the Studio Six. I kept it running in the store all day long, and after 20-30+ hours I’m beginning to hear a more proper space and bloom I expect from a $5K tube amp. The amplifier is starting to open up for sure, but still the strongest impression that the Six left on me was “what awesome dynamics!”, “what awesome bass!”.



Indeed the bass was the highlight of the Studio Six. I’ve never heard bass done the way the Six does it. The strongest slam, the hardest punch, with an uncanny focus that felt like Klitschko delivering straights, hooks, and uppercuts to you. The bass is utterly jaw dropping. Though I managed to keep my physical jaw in place, in my mind my jaw really dropped. A revelation on how bass can sound on headphones. Tight, fast, clean bass attacks, that don’t run out of steam the way single-ended tube amps typically do. Even the Manley Stingray integrated amp running in push-pull mode (~40Wpc) doesn’t do bass like this. The Apex Peak is another tube amp that has pretty good bass but with the Peak I felt that I was taking punches from Pacquiáo, whereas with the Six, Klitschko.

Intermission: “What music genre doesn’t require good bass reproduction?”

So, is this a bass head tube amp or something? I didn’t know bass heads use tube amps, but the way I’m talking about the Six, it seems that bass is all it’s got. Let me explain more.

The Six is actually fairly flat in terms of coloration. It doesn’t have a bass heavy tonality nor a bass-boosting sound or anything like that. The tonality is quite flat and may be among the most neutral sounding tube amps I’ve listened to. Those looking for a mellow, liquid-like sound won’t find it. Those looking for a grand sound stage won’t find it. Those looking for a super-lush midrange won’t find it either. The Six actually sounds a lot like a solid state somehow along the line of a Burson amp but without the typical grainy sound of a transistor amp and the “mechanical stiffness” of a solid state. I wouldn’t say that it’s a bright sounding amp but I’d certainly like a darker tonality for my dark-loving ears. It’s also quite more forward than what I like (the Continental V3 tube is the right tube tonality for me) but it makes for a superb combination with Audez’e headphones.

The sound is clean with no grain, the background black, average resolution and micro details, and with an average (in the realms of high end tube amps) sound stage space and depth, with an effortless instrument separation and positioning. It’s has a flat and uncolored sound, solid-state like speed, transients, pace, attack, and snap. Extremely fast paced, effortless instrument separation and by far best-I’ve-heard-in-a-headphone-amp-dynamics. It really has more solid state characters than it does tubes, and were it not for the clean and grainless sound, it would’ve really passed as a solid state in disguise. This amp has absolutely no problem keeping up to the pace of AC/DC.

A great sound system always demands great bass reproduction. You need treble as the icing of the cake, and the midrange is an important part of the music, but the bass is what seals off the deal. How your set up does bass is what separates the mid-fi to the high-end. Pretty easy to find a great midrange on a $2-$5K speaker, but great bass doesn’t happen until $10-20K and up (like this $400K Kharma). And while any well-designed tube amp can pull off a wonderful midrange, a really great bass is rare, even from powerful solid-state amps. And the Studio Six is rare in the fact that it’s a 100% tube, yet it does a better bass than any other headphone amp, SS or tube, I’ve tried on my reviewing career. With a bass like that, no wonder I’m still giddy whenever I think about the dynamics of the Studio Six. In fact, my heart rate just went up typing that last few sentences just now.


More on the next page…

The Awesome: ALO Studio Six
5 (100%) 1 vote

  • And here is a slightly different angle from veteran reviewer Nathan

    • Jook Yos

      Thank for more information, and i like your new style in giddy writing way so much.

      • Glad you enjoyed the article. 🙂

    • Thanks for the shout out, Mike.

      Japanese Headfiers will be getting a go with the ALO Studio Six. I’m pretty stoked about it.

  • George Lai

    Wow. I think they should rename it the Studio Sex.

    • L.

      It does look so sexy doesn’t it.

  • L.

    So bass is like this?

    Just kidding, sounds like a very good amp!

    • Dave Ulrich

      Whoa… rock n’ roll!

    • No that’s called an explosion, L. 😉

  • Gneiss

    Although I do not think this is a well priced amp, best review I have read in months!

    • Dave Ulrich

      Agree with you on both counts.

    • Thanks, Gneiss!

  • Rūdolfs Putniņš

    Yep good tube amps sound dynamic and unlike the stereotypical “tube sound”. After I finish my current amp build and a PCM1794 DAC I might actually do a nice tube build. 300ies or something like that.

  • Try a vintage RCA 6SN7! That’s what I ended up with in my Studio Six!!

    • Thanks, Mike!
      I will keep an eye for a vintage RCA 6SN7!

      • right on! and GREAT job as always Mike!!

        • Thank you, Mike!

          I suppose you’re using the Six with the LCD3 as well?

          • I am indeed! As well as my Sennheiser HD800’s and Mr. Speakers Mad Dogs! Can’t WAIT to hear it w/ the upcoming Alpha Dogs!!

  • John123John

    Havent read the review yet but I am so excited too 😀

  • Fabio_Rocks

    Alo audio makes wonderfully products, no doubt about it. Hope in the future they can sell them with better price, let’s say 10-20% less, It will be perfect!

    Mike do you have tried this alo cable:
    SXC 24-Custom IEM ? I just got the Westone Um3x, and you were right about their uninvolving sound. In my opinion that is because they have somewhat recessed highs. Do you think I will get a more present treble responce with this cable?
    Is Alo-Audio so nice to send you this cable for a review?:)

    Sorry for the question off-topic, I was thinking to post this question in the review about audio cable, but comments are closed there.


    • No problem, we have the SXC24 both for JH and for FitEar on the store. It widens the soundstage, push the midrange and low treble out and adds a nice bloom. Some people like it due to the the more forward midrange, some don’t due to the more forward midrange.
      The UM3X IMO needs more treble, not necessarily more midrange. I’m not sure if it’ll work well with the SXC24. Maybe the Silver Dragon would be a better suggestion but assuming the Silver Dragon IEM cable has the same sound as the headphone cable (I’ve only listened to the SD for headphones).

      The SXC24 however works wonderfully with the FitEar 334ToGo.

      • Fabio_Rocks

        Thanks Mike!

  • Pingback: ALO Studio Six Headphone Amplifier | Ultra High-End Audio and Home Theater Review()

  • rich

    A visit to my millionaire friend in Japan and I tried the Six against the rest of the top amps. The sound is like “wow”. “Rob, steal or starve” to buy this expensive amp. It will become a legend in years to come. ALO don’t change their models frequently compared to other manufacturers . Also buy the ones with special adds on for US$200 extra.

    The magic of tubes- warmth to the sound in spades. But this amp is neutral too. After spending almost the whole morning with this set, I am very impressed. But always remember, the audio play back is a chain. The weakest link will rear its ugly head. Make sure the sources are excellent too. Also the interconnects and power supplies are premium.

    I come from an mainstream component system,i.e. real stereo speakers, preamp, power amp and cd/ sacd players etc. The use of the Six with the best headphones can approximate or out perform real component box speakers. View from a component audiophiles point of view, this amp is not super expensive. An SACD player alone from Esoteric can cost upwards of US$10K.


      rich ; are you talking out of experience ? alo-six and stax 009 would compete with esoteric k-o1 or MSB DAC IV

  • L.

    I listened to the Six for a few hours last friday and I can mostly agree with what Mike wrote. The tubes in this Six were all NOS and weren’t the original tubes supplied by ALO.

    I have to say this is the best amplifier I have listened to, everything was great on it. Sure it’s not the smoothest, warmest or most tube like sounding amp, but oh my does it sound wonderful. With the tubes the Six had, I can’t remember which one, the sound stage actually was very wide and that’s the part I might disagree on with Mike.

    I gave Mike a rare and good ADZAM 6SN7 tube for the Six. I know he loved it but I’d love to know how it improved the soundstage.

    conclusion: extremely good looking and sounding amplifier that does great with a whole lot of headphones. Did I mention I’m in love with the Alpha Dog now?

    • It’s a good amp that’s what matters. 🙂


    the alo six best amp for the lcd3 ;how about a dac ?


    Fostex HP-A8 is your best pick all rounder dac/amp but i guess its the dac part of it that shines ,is their any supplement amp’ suggestion’ just to fulfill where the amp on this lacks ?


    The Antelope Rubicon AD/DA Preamp, The Atomic Amplifier with a lcd-3 ? ha “?

  • meh


  • Blaine Vonhagen


    • L.

      Talk about constructive comments 😀

  • Ernie

    What are those mystery phones in the picture second from the top?