Analog Squared Paper TU-05


The TU-05 is a portable amp. It runs on battery. It’s 100% tube. It’s the size of a Violectric V200. Yes, a Violectric V200. You say “whaaaaat?”. What a concept, I know. They even provide a special carrying case that has a built-in pouch for a digital audio player. Please take a look:








The idea is if you are hardcore enough about audio, you’re not going to accept compromises when it comes to even portable rigs. Yeah, I don’t need no pocket-able portable amps. And no transistor or op amps either. This is a true purist amp for the ultimate audiophile (did I just say that?) who won’t accept any compromises.

With an amp like this, it’s easy to be sold into the size and build before you even had one listen. The build quality is actually extremely high, I don’t think it can be done had it not been hand built in Japan. Though the metal case is a bit spartan, the smoothness and finish quality of the metal panels make even the panels of the ALO Studio Six seems rough. I think I may have fallen for the size and build even before I had a listen. I was really impressed the first time I listened to it with the LCD-X. The vocals were crisp yet smooth and full bodied. On the score of vocals alone the Analog Squared Paper TU-05 can easily compete with bigger desktop tube amps costing twice its price. I spent a total of two weeks with the amp, and it was an impressive amp that easily trumps top performing portables like the ALO Continental, RSA Intruder, and Portaphile 627, and more in the league of the ALO PanAm and Violectric V200.

It’s not an all-conquering amp though, and personally, I wasn’t so thrilled with the soft grain, soft mellow character of the amplifier. I can’t deny that it’s an excellent amp, but in terms of sound signature, I wanted more PRaT and slamming bass. Ultimately though, it’s a pairing game as I find that the TU-05 works magic with the Japanese wood headphones like the Audio Technica W2002 or the Fostex TH-900. Special note with the TH-900: it’s easily the best amp I’ve have heard it with, rivaling the Bakoon HDA-5210mk3 and easily better than the ALO Studio Six. Though it plays well with the LCD-3, I personally still prefer the ALO PanAm or Violectric V200 pairing. But these are personal tastes and I can see the next person can easily prefer the LCD-3 + TU-05 pairing. The TH-900 pairing is sublime though and the TU-05 is one of the must-try amps for TH-900 owners.

The owner of the amp who provided his TU-05 for me for review had also loaned me several card-boxes with tubes specifically for this amp. I didn’t think I’d ever see such a range of choices for rolling tubes ever in my life. In fact there were so many tubes I think I only ended up testing about 15% of the collection. Each tube brought different coloration, but after rolling some 20 different pair of tubes I was still unable to find something that would improve the dynamics enough to make me change my feelings toward the amp. Overall it’s still mellow, grainy, and has a little less bass than I’d like.

Gain level is not excessive and though I didn’t lack any power for driving the LCD-3, I was usually always around 2-pm to max Level.I personally prefer playing my amps with the potentiometer near the fully-open level so it works out just fine for me. Using it with an IEM is generally not an issue. There is some hiss audible when no music is playing (using LimeEars LE3 46Ω, 109dB) starting around 12 o’clock but still very slight up to 2pm. With music playing, however, I don’t hear any hiss at all.

The TU-05 can be ordered in multiple configurations with each option likely to add more to the cost. Going for the classy gold case instead of the standard silver or black costs an additional 6,000 Yen. It’s a nice champagne color that’s close to the gold Iphone 5S but slightly more muted and soft. You also get output impedance options, upgraded capacitors (3,000 yen), upgraded potentiometer (3,000 yen) and even additional costs for accessories that I think should come as a standard like a tube guard panel (5,000 yen) and the mandatory carrying case (a whopping 30,000 yen, though it does use a rugged, high quality leather). I tried configuring a full-out build and came out with a price tag of 141,000 yen which is roughly a bit below $1,400 USD. A minimal unit came out to be 94,000 yen.

There are some tube micro-phonics when you plug/unplug your headphones, but carrying the amplifier around in its bag, the micro-phonics happens very rarely and again, is not an issue for me. The last point I need to address is battery life but I’m always lousy at keeping track of battery life.


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  • George Lai

    I don’t know why but the first photo reminded me of the battery packs I used to carry for my VHS video recorder. Ah, memories. Interesting product though. This amp I meant.

    • L.

      Now that you mention it…

  • Jeffrey Coleman

    I love following this guy on Facebook. He posts pics of every single amp he produces (which to be fair isn’t many). You see every variation (paint colors, led colors, balanced output, leather pouch colors). It really is beautiful work, and the definition of boutique.

    I hope to own one of these or the little brother, the TUR-06. But other things in this hobby must come first, like a top notch source.

    Mike, I hope you have the opportunity to also review the TUR-06. I would love to hear your impressions.

    Once again, thanks for sharing…

    • L.

      Our pleasure!

    • Thanks Jeff. I’ll try getting the TUR-06.

  • spudgered

    Guys, there is a burgeoning thread on Head-Fi of tu-05/tu-06 owners where we discuss tube rolling, headphone compatibility, isolation supports and just about everything else relating to these fine amplifiers. It’s worth a look if you’re interested in these amps.

    • L.

      Feel free to post the link, that’s ok!

      • spudgered

        Thank you, link posted.

    • Thanks.

      As mentioned, I got tons of tubes to try the TU-05 with. Keep in mind that with tube rolling impressions is, different batch tubes even though same make and model, give a different sound. The same tube, different age, will usually sound darker.

    • Thank you!

  • spudgered

    Here’s a link to the Head-Fi thread – – we are a very friendly bunch and are happy to answer questions about the amps.

    • L.


  • SallyMaeSusan

    There is no denying this device is ABSOLUTELY GORGEOUS!
    However, I am rather stunned that the reviewer could not exact the ‘bite’ he so desired. Not so good…

  • bmichels

    I am very happy that you find the tU-05 + TH900 an exceptional match, because … it is exactly my set-up and I must agree that it is sublime ! BUT…. AREN’T YOU OVER-OPTIMISTIC when you state that ” …. with the TH-900: it’s easily the best amp I’ve have heard it with, rivaling the Bakoon HDA-5210mk3 and easily better than the ALO Studio Six” ?? The Studio Six is a $ 5000 super uber amp !! have you compared booth with the TH-900 ?
    -> I am more than interested because I planed to “upgrade” my TU-05 with an ALO SIX (or Bakoon HP-21 or HAR HP-4) for “at-home” listening cessions ! So may be you saved me $ 5000 🙂