Review on AIYIMA Tube T4 HiFi Stereo Audio Power Amplifier Bluetooth 5.1 Vacuum Tube Amp - 100Wx2 Stereo Receiver APTX-HD for Home Theater System + DC 32V Power Adapter (Black- T4) by Charlotte Manning

First of all I have to admit that I'm a bit of an Ayima fan. The T2 Pro 6J1 is the fourth Aiyima amp I've bought for home use in the past year. The first three units are used together in the main system in my living room: A3001, A04 and A07. T2 Pro 6J1 is used in a secondary system in my office. This is my first tube amp and it is implemented as follows: MacBook Air 2015 (music app) > Realtek USB 2.0 Dongle DAC (24bit/192kHz) > FosPower 3.5mm to RCA Y-Hub > Aiyima T2 Pro 6J1 ( standard) > 16 AWG twisted pair with FosPower banana plugs > Sansui SP-200 3-way speaker (rebuilt circa 1969). This unit uses a Texas Instruments 3116 chip, an amplifier I have a decent experience with this inexpensive chip that started my return to the HiFi world over two and a half years ago. As a general rule, I've found that prolonged listening through the 3116 amplification inevitably leads to what is known as "ear fatigue". Until you experience it for yourself, it's an odd concept to wrap your mind around. It tends to build up slowly until it becomes disconcerting and frankly annoying to listen to. I am happy to report that the T2 Pro 6J1 does not suffer from this phenomenon. I'm not sure if this is due to the overall architecture of the unit or the implementation of the 6J1 tubes, but it certainly produces warmth and depth that your ears will surely enjoy after prolonged listening. The female vocals are alluring, the bass is deep and tight, and the highs are nice and clear. Given my experience with previous 3116 amps I was a little hesitant to take the plunge but in the end I'm glad I did as I was keen to use the Sansui SP-200 with tubes. In short, I listen to the T2 Pro 6J1 for hours at work and never experience listener fatigue. Well done, Aiyima! Pros: Sounds great right out of the box! No pops, hiss or other background noise sometimes found in 3116 amplifiers. Effectively eliminates listener fatigue syndrome. The physical BT switch (5.0) eliminates unauthorized capture of the BT signal. Power supply and/or lamp replacement. Cons: Not a powerhouse by any means, better for background noise listening