Pros: Many tube-rolling options, works well with high impedance cans, performance for price is great
Cons: Gets physically hot, needs desktop (less portable than some combos), stock amp is mediocore
The Aune T1 is a great DAC/amp combo on a budget, with the ability for tube-rolling which makes it a winner compared to other portable solid state DAC/amp combos in its price range. I reviewed my T1 listening on Sennheiser HD 650s, and I think it pairs up very nicely with them.
My T1 came packaged in a nice cardboard box, with plenty of foam packing to prevent damage to any components. The tube also came packaged inside the foam, as it is quite fragile. If you're unboxing your T1, make sure to look for the tube inside the foam packaging, as some others have missed it! Also included is an instruction guide, USB cable, and wall adapter (there are two separate adapters; one for 220V and the other 110V).
The T1 comes in two flavours; silver or black. I have the black edition, and the case looks very slick. The tube itself plugs in the top, beside a round volume dial. Headphone jack is located on the front of the case, and USB, power, and RCA jacks are all located on the back. There are also dip switches located on the bottom of the unit, for adjusting the gain settings for the amplifier. (0db, +8db and +16db settings are available). Overall, I am impressed with the case, jacks and volume dial. The case itself looks modern and has rounded corners for a stylish look. There are plastic guards that are supposed to snap in around the top of the tube to prevent contact with the tube, but I think they look very cheap and did not install them. There is no additional guard to go over the tube, which is not an issue for myself.
While the T1 is on, the case itself will get warm, then may even get hot to the touch. This leads me to only leave it powered on while I am in the vacinity of the T1, as I am overly cautious. I would strongly advise the same, which may be an issue for some. There are others who leave their units powered on 24/7, but I don't like the fact that the case warms up.
The T1 can be opened up very easily, and I actually upgraded the capacitors inside of mine. It came with a mix of Nichicon, Panasonic, and ELNA capacitors, which I opted to remove and replace with ELNA Silmic II, and Panasonic FR capacitors. I had no issues with the stock capacitors themselves, I just wanted to further refine the sound of my unit.
Input - the T1 requires a USB input to play the music through the tube portion of the DAC. It is limited to a max of 24bit/96kHz which is great. There is also an RCA input which will go through the amplifier portion of the T1 only. If you plug in via RCA, the DAC and tube will not be in use.
Output - The 1/4" headphone jack can work solo, or also in conjunction with RCA outputs which can feed an amplifier and speakers. I honestly enjoyed the headphone amp of the T1, although I have heard it reviewed by others as mediocore. After upgrading the capacitors, the headphone amp now sounds amazing.
The T1 uses a Burr-Brown chip inside of its DAC, along with the tube buffer. The quality of the sound with the T1 will vary greatly depending on which tube is being used. Mine came with the "upgraded" Electroharmonix 6922 tube, which I quite enjoyed. It sounded slightly warm, with decent separation between bass, mids, and highs. I noticed clarity in the bass compared to my laptop's soundcard, which was more bass heavy and muddled. The mids and highs were also pleasant sounding, although I found that the highs were a bit bright for my liking. Overall, it was a nice upgrade from my laptop's soundcard, but I wanted to refine the sound even further.
I rolled in a Phillips JAN 6922 tube which cost $15, and immediately noticed the mids became slightly richer sounding, and the soundstage layered out. I preferred this tube to the EH 6922.
I then rolled a Siemens E88CC gold pin tube, which cost around $45, and was astounded by its presentation of the highs... female vocals were nuanced, refined, highly detailed and spacious/airy. Cymbals shimmered without any brightness, and the height between bass/mids to highs was expanded. I was in love with my collection of female vocalists.
Onward to the Amperex 7308, which I am currently enjoying. Beautiful, rich sounding mids, and detailed highs (although not quite to the extent of the Siemens tube). Layering and imaging beyond belief... this puts any other amp/dac combo in the T1's price range to shame. These 7308 tubes come in many different variations, and can be found on ebay from $15 to $200 and up. I would expect to pay around $45 for a nice 7308 tube.
As mentioned, I also opted to upgrade my capacitors inside the T1. I bought my new capacitors online for $25, and it took a couple of hours to open the unit, do the soldering, and close it back up. The change in sound is very, very nice. Beautiful, refined, liquid gold is now shimmering from my T1. I highly recommend this upgrade as well. (Details can be found here, on the T1 Discussion Forum).
To recap, the T1 is a great option if you are playing digital files at home, or at the office. It requires a dedicated setup on the desk, and I would also recommend feeding it CD quality FLAC files, or 320kbps mp3s. I would also recommend upgrading the tube, as the sound definitely changes with different tubes. The capacitor upgrade is not mandatory for beautiful sound, but it will take your T1 to a level far beyond its price point.
For less than $200, the T1 is a great way to enjoy warm, detailed, layered sound. I highly recommend the T1, and also recommend reading the T1 Discussion Forum here on headfi, as there is plenty of info from other users. I rate the T1 at 4.5 out of 5 stars.