I have always been into music on hi-fi systems. As a little boy, I listened to my grandpa's stereo on headphones.
I have a vast recording collection. I worked at Radio Shack in the 1990s and was a Certified Audio Specialist, if I remember what it said on my badge correctly. I have been curious about vintage tech lately. I got into vinyl, and agree that it can sound better than digital in many cases. I have sought out and listened to digitized versions of quadraphonic recordings from the 1970s. I enjoyed them and wish they would re-release them all in some form. My latest curiosity has been tube-type amplifiers. Many online insist that they sound so much better than solid-state amplifiers that there is really no comparison. Are they just romanticizing old-fashioned things, or are they on to something? I didn t want to spend a fortune finding out, but did want to know. I looked into finding restored vintage gear, but found that it was not feasible. What I decided to buy once I saw it on sale was a Monoprice Stereo Hybrid Tube Amplifier.
Its preamplifier stage has four vacuum tubes, and its power amplifier stage is Class AB with 25 watts per channel. Once I had it, I decided to compare it to my home theater surround receiver, an Onkyo TX-NR797. I was impressed!
People online were saying that a tube amp sounds more natural, more real. It creates a more three-dimensional sound stage making you feel like you are hearing a band play live. It was not just hype. I heard the difference immediately. The treble was what really impressed. It had more presence. It was more full. My only regret was that with only 25 watts, I could not really crank it up, but my curiosity was satisfied. It was all it had been cracked up to be. I decided I wanted this sound in my home office and bedroom too, but needed something smaller in those spaces as room is limited.
When I started to research small tube amps, two stuck out as interesting: The Douk Audio ST-01 PRO and the Fosi Audio MC331. To compare the two, I needed to buy both.
Eventually, I would put one in each space. These models have only one vacuum tube per channel and are small enough to fit nearly anywhere. They both use the same U.S. made GE tubes and have Class D power amplifiers. The Douk advertised 100 watts per channel at 4 ohms and the Fosi 105. Since my speakers and most home speakers are 8 Ohms, that makes it 50 watts, enough to crank it up in a small space. Listening to these, I was not as impressed with the treble, but the bass really stood out. Over Onkyo Model SKF 200F speakers, they sounded a bit boomy, but on a pair of vintage Optimus Pro 7 speakers, sounded natural.
Comparing them to the big amp in the living room, these small amps have may features I like. Both have remote controls. The Monoprice model does not. It has physical switches that would make it having a remote impossible. I have to do everything manually on it. One of the physical switches is even on the back in a hard-to-reach location. I have set it up so I almost never need to use that one.
I will go into detail about each model. First, the Monoprice: It has RCA inputs for phono and CD, an optical digital input, a coaxial digital input, a USB port for music on a thumb drive, Bluetooth connectivity and a Walkman size headphone jack. It has a control for moving from track to track on a thumb drive, a VU meter with a blue backlight as well as blue for the power button and blue lighting up the tubes. I like the look of it and the sound in spite of the lack of a remote and inconvenient physical switch I mentioned before. I do not use the phono input as the built in preamp of my audio-technica turntable gives me louder sound when I want to play it loud. I connect a CD, the turntable and a cassette deck to the CD input using an old Archer switchbox from Radio Shack. I frequently wish they were still around.
I also have an Oppo DVD player that can play DVD-Audio and SACD as well as HDCD and regular CDs connected coaxial and a smart TV connected via TOSLINK. I am not whether the DAC built into the player or the one built into the amp sounds better, but articles I have read say that digital to analog conversion should be done as late as possible for best sound, so I usually use the digital connection and let the amp do the conversion instead of the player.
The smaller amps both have amber lighting and have many of the same connections, but the Douk has a dedicated USB port for a thumb drive and controls to go through one. The Fosi does not have that. The Fosi has a USC-C connector for hooking it up to a computer as an audio device. The Douk has a USB device connector like you would find on a printer. The Fosi has protective covers for the tubes. The Douk does not, but they are deep enough into the amp that their location provides some protection.
At first, I noticed some interference on both amps in my home office, a faint tick tick tick sound. The manual for the Douk suggests that tubes are susceptible to harmful interference. After some experimentation, I figured out I was placing the amps too close to a Wi-Fi router. Moving it fixed the noise. In my home office with the Optimus speakers, I could not really hear a difference between the Douk and the Fosi. It was much the same in the living room on the Onkyo speakers. They sounded the same. Cosmetically, I like the rounded edges and compact design of the Fosi more than the Dou. It looks kind of boxy, but the Douk s ability to use a thumb drive for digital music makes it a good buy. Comparing the remotes, the Douk is a bit generic looking, and has two buttons that don't seem to do anything. The Fosi remote has a streamlined appearance and all controls can be done with it.
It is clear to me that what they are saying online is not just hype. Tube amplifiers do indeed sound better than solid-state. It was not just nostalgia for old-fashioned things. I think that they do a better job of separating the right and left channels. You get closer to the binaural sound your two ears hear in the real world. There seemed to be more crosstalk between the left and the right on my solid state amp. Still, the only way to completely eliminate crosstalk is to use headphones.
NOTE: I do not have endorsement deals from any of the brands I mentioned. They are products I own. That is all.