It will sound just fine but if it goes through a transistor at any point in the audio chain, the whole point of tubes is kind of rendered moot, other than aesthetics.

Very true. That specific device is only 5V, basically enough to warm up the heaters and use the tube as sort of a buffer, at most, nothing more. The NE5532's are doing all the work.

If I get it, it would indeed be for the aesthetics as it's basic functionality is just as a headphone amp. The only reason I'm even looking at it was the cheap price. I could get any old inexpensive decent amp for what I'm wanting it to do. I just wasn't how much that so called buffering would alter the audio. Like you suggest, probably not much. However, I'm outside my realm of expertise when it comes to tubes. 😀

I really don’t think it would alter the audio much based on what you just said. I think the silicon would clip hard before the tubes could do anything.

I think at this point, it's a toss up between the ready to go aesthetically pleasing option, or build one on my own using something simple like this...

https://www.amazon.com/HiLetgo-Preamplifier-A … /dp/B082LVYKTC? or similar.

I guess it just comes down to how much I want to spend and how much time I want to invest. Well, and how confident I am in my ability to make it look nice.

Thanks for the feedback. 😀

I just built mine myself - power supply and opamps.

Tubes need more than 5V to actually handle signal.

If you were wondering about tube sound, the soft harmonic distortion they introduce "warms up" the audio's vibe and pleases some people. Basically sounds like an old tube radio 😀

Edit: on another note, the output impedance of a tube amplifier is higher than that of a transistor amp, which causes it to deliver more power to higher impedance than a pure voltage source would. As a largish loudspeaker's resonant frequency is quite low and electrical impedance peaks at resonance, it should deliver slightly more bass on a tube amplifier... perhaps that is the main contributor to the perceived warmness. It would not have the same effect on headphones, as their transducers are physically much smaller and should have a higher natural resonant frequency.

Well, I ended up getting the "ready to go aesthetically pleasing option". Hard to beat at that price, and it works perfectly for what I'm asking it to do.

It also works pretty much how I suspected. The L&R channels are each amplified by the trusty old-school NE5532 op-amps. From there each channel passes through one of the 6J5 tubes to add a bit of "warmth" to the NE5532 output. It takes about 15-20 seconds for the heaters in the tubes to get hot enough to allow the audio signal to pass through.

Do the tubes have a noticeable effect on the audio output? Yes, it definitely adds a bit of warmth to the sound (as suspected), in a good way in my opinion. There are no added distortions, noises, or anything else. I tested it on several games on both my RetroPie and DOS machines. Listened to several of my favorites tunes via FastTracker 2, and everything sounded great. No need for any of my original concerns. As a simple headphone amp, it works perfectly. Overall, it does indeed sound better, at least to my old ears, than the old powered Logitech speakers I was using.

After about 5 minutes of operation, the tubes get up to about 130F (54C) at an ambient room temp of 72F (22C). Measured using an IR thermometer. So they get quite warm to the touch. Not bad for a 5V 2A powered device. 🤣

The blue light at the bottom of the tubes is just an LED, there for aesthetic effect. The red glow is from the internal tube heaters.

Overall, I'm happy with it. It does what I wanted it to do, and in this old geeks opinions, looks pretty cool doing it. 😀