Review on AIYIMA Tube T6 PRO Bluetooth 5.0 Tube Preamplifier - Hi-Fi Headphone Amp, Vacuum Tube Preamp for Home Audio Amplifier, Wireless Receiver, Audio Decoder, Preamp PC-USB DAC with APTX by Jose Guevara

I used an Aiyima A3 lamp. There's nothing wrong with this block, but this one is way ahead of it. It's a bit bigger but has a USB deck, Bluetooth and a headphone jack. I was very impressed with the Bluetooth range. I live in a house of about 3500 square feet and Bluetooth is connected throughout the house. I couldn't believe it. I tested it without the antenna turned on, and if you need range, you will definitely need it. The headphone jack was another revelation. As soon as you plug in the headphones, they immediately switch from playback to headphones. There is absolutely no lag when plugging or unplugging the headphones. I tested both high and low frequencies with the knobs. I had plus or minus 10 decibels in the bass and plus or minus 6 decibels in the highs. So I got a bit better bass boost and cut than advertised, which is always a positive. The only downside to this preamp is that it comes with Chinese tubes. You can improve the sound quality by replacing the tubes with something like GE. But that's the great thing about this preamp. There are many tubes that work with it. So you can really get the sound you want.