After listening to the Dot I tube amp. I hesitated to post my comment in the forum because I would’ve ruin Mr. Yang (designer of the amp) reputation especially the newly designed Dot II amp is in the final designed stage. One thing most people do not know is that Mr. Yang designed/build this amp as a hobby, somehow, the word gets out and hobbyist (financial constraint college Students) in China goes wild about his amp due to the price and sound quality.
Ok enough rant, what is the amp like? As far as ergonomics are concerned, think swap meet. I was disappointed; it reminds me of the early day’s DIY transistor radio kit that I ordered through the Popular Science magazine (which I still haven’t finished). I know it cost about USD $30 in China, but factoring in the shipping cost to the States; you are looking about almost an USD $100 product. I am the kind of person who always appreciates simplicity but to me this called cheapness. The casing is from the surplus store, screws are mismatch. The housing edge are not polish, if you ran your hands through the amp housing, you’re bound to have cuts on your palm. The power cord is build into the amp and the audio input is fed via a mini 1/8 inch phono jack, most people would preferred a pair of female RCA. All this said, this was intended for the budgeted hobbyist who wants to try out their first tube amp.
Now let’s do some damage repair. How does it sound? Please keep in mind that sound quality is a subjective matter, and I am no audiophile by any stretch of imaginations. So take what I said with a bucket of salts. I tested out the amp with two headphones: Audio Technica ATH-W2002 and Sennhiser HD-650, I couldn’t remember the make/model for audio transport and the audio source was mostly Chinese music (Terrisa Tseng).
The W2002 is low impedance cans (32 ohm), the Dot I was build for a much higher loading cans (150 – 600 ohm). Just a side note, personally I tried many different manufacture tube amps with this pair of headphone and come out quite disappointed. The DOT I was not much difference. It has the weakest bass and a roll-off in the high frequencies. I was very under whelmed, the sound is very harsh and it made it painful to listen to at a higher volume. In less then one minute of listening, I almost throw myself out the window of an 18th floor building.
Moving on to the Sennhiser HD-650 (150 ohm). Going back and listen the same CD track…ahhhhhhhhhhh…, The sound was delicate, pure, and detailed, from a warm bottom end to an open, detailed top. In particular, had virtually no overhang or boom. Cymbals come through crystal clear. Bass is also definitely more prominent than the W2002. If I scratch around in search of a quibble, it might be of a slightly too prominent top end.
Another thing worth mentioning and this happens on both headphones. With the amp switch on and volume level turn all the way down, I could hear a slight electrical hum, the humming became louder if I place my hand on the amp housing. However, once you start listening to music, the hum became inaudible.
So would I recommend buying this amp? I have to say NO, not because it sounded crappy. Contrary, the Dot I mini tube amp can provide a thoroughly musical experience when paired with the proper phones. Considering the newer revision (DOT II) amp is underway and should be complete soon, I will have to say sit back and wait to see what Mr. Yang have up his sleeve.
