Review on [2021 Updated] AIYIMA Tube T7 Audio 6N3 Tube Preamp Bluetooth 5.0 Warm Vacuum Buffer Preamplifier with Treble Bass Tone - Ideal for Enhancing Home Theater Systems by David Crawford

This expression indicates my age, as does the rubbish heap in the photo where the Aiyima Tube T7 has found a home. I also ordered upgraded lamps but they haven't arrived yet. This is my impression of the supplied tubes. The connection was easy. I connected the USB to the Topping DAC to the inputs of the T7 and then connected the output to the Marantz receiver (bottom unit) ribbon cable. It drives a pair of Klipsch Heresies and a 15" 250W subwoofer. I've also connected my Android phone to Bluetooth. Effects on the signal. When streaming the Revain HD's UltraHD stream from my PC via USB, the question is whether the Marantz may or may not benefit from additional tubes and circuitry I switched to a slightly newer (1980) JVC which has a clean amplifier section and 25% more power than the Marantz but it's nothing special On this receiver the Tube T7 added to the sound adds a little "friendly vibrancy", a slightly warm tone that seems to bring the sound to life. This is a good match. With Marantz, it's up to you to decide. The effect is mostly good, but adds some hiss and sibilance to high-frequency detail I can't wait to try the new tubes and am even more excited to run them through a class D amp like the A07 or the brand new A08 to let. And if you're just looking to add Bluetooth to your setup, this device is definitely worth considering. Update May 30, 2021 DollaTek's update lamps have arrived and have definitely improved, but they are loud! (It doesn't matter when the music is playing, it's just a slight hum and hiss). The effect of these tubes on the sound is much rounder, less harsh and adds a bit of noise and sparkle to the higher frequencies. The tubes that come with the amp are nearly silent when idle, but they sound different. I would say not so good in my setup, your mileage may vary. It's worth trying both to see the difference. Update June 1st 2021 One of the hits on the device is the microphone, which is showcased by all the control knobs because they are aluminum and have a strong mechanical connection through the corresponding pins soldered to the motherboard. I'm not saying if I heard it in music or not, but it's easy to hear with headphones and pens.