Putting the T6 Pro Tube Preamp to the Test

Aiyima Tube T6 Pro Preamp

The Aiyima Tube T6 Pro preamp is designed to add a little warmth back to you recordings And that is exactly what this does. However, it does a whole lot more. Let’s first explain how you would use a product like this. This goes between your source and your amplifier. The source signal then goes through your tube preamp, adding the warmer sound to your music before it goes to your amplifier. They typical way to hook up a preamp like this is to use RCA cables. However this one has now only your RCA inputs, but also adds bluetooth and a USB DAC. You just select the input with a toggle switch on the front. It also adds a treble knob and bass knob as well as a headphone input. These are supposed to have the ability to increase and decrease your bass and treble by 6db. But a company can claim whatever they want, we really need to test it to see how good it really is.

What Does it Come With?

It comes with an all aluminum preamp with four small rubber feet on the bottom. In addition it comes with a very basic manual, a small 12v power supply, a bright blue usb cable for the DAC and two Chinese tubes. I’m not a fan of the bright blue USB cable , but I am glad it comes with one. I also wouldn’t mind some higher quality tubes, but at this price, I really can’t complain. Not to mention upgrading tubes is easy and cheap to do. Especially since the tubes one uses will be highly preferential.

Testing

Before we go too far into testing, I will mention that it does add the warm sound back to your music. The exact sound signature you receive will depend on the tubes you use. You can use the ones that come with it, but they are typically lower grade. However the sound signature you want is going to vary from person to person. Luckily this does use multiple different types of tubes. Some of these tubes include: 6J1, 6J2, 6AK5, 6AK5W, 6F31 ,6BA6, 6K4п, GE5654, 6Ж1п and more. One of the most common and highly rated tubes that users upgrade to are these GE ones. Having said that, these tests were done with the tubes that come with the Aiyima Tube T6 Pro preamp.

Bluetooth Range

The T6 Pro comes with an external bluetooth antenna. It is plastic and relatively ugly looking compared to the nice sleek unit. But by adding an external antenna the hope is that you will get extended range. Does it?

I first hooked up the external antenna and turned on bluetooth on my Samsung Galaxy S20. Now I just checked the range in my house. I live in about a 3500 square foot house, that is two stories. The office I had it in is about center of the house and on the upstairs floor. To much of my surprise, I was able to get and maintain bluetooth signal no matter where I took my phone in my house. This is the first unit I can remember that was able to do that. I was so excited that I decided to try it without the external antenna.

I had a completely different experience when I did this. Without the antenna on, I was able to go outside my office door and about 5 feet down the hallway before I lost signal. With this in mind, I recommend keeping the external antenna on if you plan to use it for bluetooth.

DAC Test

As soon as I plugged this up to my computer with the included USB Cable, it was recognized. No firmware was installed, it just started working. In fact, my computer automatically switched over to it. It was labeled “Headphones” by Hifi Audio. I was able to select up to 2 channel 186Khz Studio quality for the DAC. According to windows that is the highest setting the DAC is capable of. It worked flawlessly with my custom computer build.

Headphone Test

This does have a headphone jack. With a lot of inexpensive preamps like this, I don’t like the headphone jack. This is for one of two reasons, one they usually don’t switch over very quickly, aka they have a considerable lag. Or second, if they do switch over quickly, they do not shut the main audio off. I was really impressed with this preamp. It switched over to my headphone immediately! No lag at all and it completely turned off the source you were listening to. That worked on all three of the inputs. I left being very impressed for such an inexpensive preamp.

Knob Test

Finally, does this preamp do as it claims, increase and decrease the bass by +-6dB? In order to find out, I hooked up my measurement system to a a Dayton MK 402. Th system I use for measurements is the Omnimic – which you can learn about here. I first took a baseline measurement with just the amplifier and speaker hooked up. Then I tested each knob.

The volume knob was able to amplify the signal more than what it was when the preamp was not hooked up. In order to get to the normal volume of the amplifier, the knob had to be a little past halfway. I ended up measure +/- about 10dB with the Bass knob and +/- 6-6.5 in with the treble knob. All of these knobs either met or exceeded what Aiyima claims. That is a huge plus.

Final Thoughts

I came away really impressed with this unit. It exceeded the manufacturers specs, instantaneously switched when I plugged or unplugged in my headphones, and the bluetooth range was phenomenal. If you are interested in a Tube Preamp for that warmer sound and want one that has bluetooth, DAC and heaphone in, I would definitely consider this Tube T6 PRO Preamp. If you just want a preamp with RCA, check out their little brother.