--- product_id: 473216135 title: "ST-01 PRO 200W Bluetooth Amplifier, 2 Channel Vacuum Tube Power Amp with USB DAC/Coaxial Optical Inputs/VU Meter/Treble Bass Control for Home Theater/Stereo Speakers (Upgrade Version)" brand: "douk audio" price: "€ 196.49" currency: EUR in_stock: true reviews_count: 13 category: "Douk Audio" url: https://www.desertcart.sk/products/473216135-st-01-pro-200w-bluetooth-amplifier-2-channel-vacuum-tube store_origin: SK region: Slovakia --- # Vintage VU meter with sensitivity control Bluetooth 5.0 & multi digital inputs 200W peak power output ST-01 PRO 200W Bluetooth Amplifier, 2 Channel Vacuum Tube Power Amp with USB DAC/Coaxial Optical Inputs/VU Meter/Treble Bass Control for Home Theater/Stereo Speakers (Upgrade Version) **Brand:** douk audio **Price:** € 196.49 **Availability:** ✅ In Stock ## Summary > 🎶 Vintage vibes, modern power — amplify your audio lifestyle! ## Quick Answers - **What is this?** ST-01 PRO 200W Bluetooth Amplifier, 2 Channel Vacuum Tube Power Amp with USB DAC/Coaxial Optical Inputs/VU Meter/Treble Bass Control for Home Theater/Stereo Speakers (Upgrade Version) by douk audio - **How much does it cost?** € 196.49 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.sk](https://www.desertcart.sk/products/473216135-st-01-pro-200w-bluetooth-amplifier-2-channel-vacuum-tube) ## Best For - douk audio enthusiasts ## Why This Product - Trusted douk audio brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Seamless Connectivity:** Bluetooth 5.0, USB DAC, coaxial, optical, and RCA inputs ensure flawless compatibility with all your favorite devices—phones, TVs, computers, and more. - • **Tailor Your Soundscape:** Dedicated treble and bass knobs let you customize highs and lows for a perfectly balanced, hi-fi listening experience that suits your unique taste. - • **Power that Packs a Punch:** Delivers robust 100W per channel to effortlessly drive 3-8Ω passive speakers, filling your space with rich, room-rocking sound. - • **Expand Your Audio Universe:** 3.5mm AUX output enables easy connection to additional amps or subwoofers, creating immersive multi-channel home theater or stereo systems. - • **Analog Charm Meets Modern Tech:** Dynamic VU meter with adjustable sensitivity adds a warm, vintage glow that visually syncs with your music, elevating your audio setup’s aesthetic. ## Overview The Douk Audio ST-01 PRO is a compact yet powerful 2-channel vacuum tube amplifier delivering 100W per channel with versatile digital inputs including Bluetooth 5.0, USB DAC, coaxial, and optical. Featuring a stylish vintage VU meter with adjustable sensitivity and tone controls for bass and treble, it offers audiophiles a warm, customizable sound experience. Its AUX output supports multi-channel expansion, making it ideal for home theater and stereo setups seeking a blend of classic analog charm and modern connectivity. ## Description Product description Douk Audio ST-01 PRO 200W Bluetooth Amplifier Vintage Visuals, Modern Precision Gold VU meters dance with sound; tubes add warm analog tones in a compact design. Wireless HD Audio Streaming Stream CD-quality audio wirelessly—stable, low-latency for phones, tablets & laptops. Universal Audio Compatibility Connect via USB DAC, OPT/COAX, RCA, U-disk (FLAC/APE/WAV), or Bluetooth—supports all sources. Hi-Fi Dynamics, Custom Bass/Treble Powers 3–8Ω speakers; ±6dB tone controls shape highs and lows to your taste. Command Your Sound Experience Adjust volume, inputs, and playbackfrom your couch. No need to approach the unit. Cinema Immersion Simplified Compact powerhouse driving bookshelf/floor speakers. Warm tube sound meets theater-scale dynamics. Premium Soundworkspace Solution Hi-Fi clarity on your desk– fits 4.5-inch wide spaces. Subwoofer AUX Output Ready Use the 3.5mm AUX out to link active subwoofers. Add deep, multi-channel bass systems. Technical Specifications What upgrades does the PRO version offer?​​ The upgraded ST-01 PRO adds U-disk input for lossless formats, adjustable VU meter sensitivity for signal matching, and decorative gold rings for a premium look. Enhances usability and aesthetics. What upgrades does the PRO version offer?​​ The upgraded ST-01 PRO adds U-disk input for lossless formats, adjustable VU meter sensitivity for signal matching, and decorative gold rings for a premium look. Enhances usability and aesthetics. How does the VU meter improve my setup?​​ It dynamically dances to music under warm lighting, creating vintage vibes and enhancing room decor. Perfect for immersive HiFi experiences. How does the VU meter improve my setup?​​ It dynamically dances to music under warm lighting, creating vintage vibes and enhancing room decor. Perfect for immersive HiFi experiences. Can I customize the sound output?​​ Yes! Use treble/bass controls (±6dB) and vacuum tubes to warm audio, eliminating digital harshness. Ideal for personalized, sweet-sounding HiFi with deep lows and clear highs. Can I customize the sound output?​​ Yes! Use treble/bass controls (±6dB) and vacuum tubes to warm audio, eliminating digital harshness. Ideal for personalized, sweet-sounding HiFi with deep lows and clear highs. What speakers work with this amplifier?​​ Drives all 3-8Ω passive speakers with 200W total power. Includes AUX output for connecting subs or additional amps, enabling easy multi-channel home theater setups. What speakers work with this amplifier?​​ Drives all 3-8Ω passive speakers with 200W total power. Includes AUX output for connecting subs or additional amps, enabling easy multi-channel home theater setups. Which devices connect to its inputs?​​ Compatible with phones, PCs, TVs, and more via Bluetooth 5.0, USB, coaxial/optical, or RCA. Supports high-res audio up to 192KHz/24Bit for audiophiles. Which devices connect to its inputs?​​ Compatible with phones, PCs, TVs, and more via Bluetooth 5.0, USB, coaxial/optical, or RCA. Supports high-res audio up to 192KHz/24Bit for audiophiles. Douk Audio & Nobsound Douk Audio ST-01 PRO Type: Bluetooth Tube Amp Channel: 2.0/2.1 Inputs: BT/RCA/USB/OPT/UDisk Outputs: Speakers+Active SUB Power: 100W x2 Tone Control: Learn More Douk Audio ST-01 PRO Type Bluetooth Tube Amp Channel 2.0/2.1 Inputs BT/RCA/USB/OPT/UDisk Outputs Speakers+Active SUB Power 100W x2 Tone Control Douk Audio ST-01 PLUS Type: Bluetooth Phono Amp Channel: 2.0/2.1 Inputs: BT/RCA/MM Turntable Outputs: Speakers+Active SUB Power: 300W x2 Tone Control: Learn More Douk Audio ST-01 PLUS Bluetooth Phono Amp BT/RCA/MM Turntable 300W x2 Douk Audio M1 PRO Type: Bluetooth Amplifier Channel: 2.0/2.1 Inputs: Bluetooth/RCA/Udisk Outputs: Speakers+Active SUB Power: 160W x2 Tone Control: Learn More Douk Audio M1 PRO Bluetooth Amplifier Bluetooth/RCA/Udisk 160W x2 Douk Audio M4 Type: 4-CH Bluetooth Amp Channel: 4.0 Inputs: Bluetooth/RCA/Udisk Outputs: Speakers Power: 50W x4 Tone Control: Learn More Douk Audio M4 4-CH Bluetooth Amp 4.0 Speakers 50W x4 Douk Audio VU3 PRO Type: Amp/Speaker Switch Channel: 2-Way Inputs: Amplifiers Outputs: Speakers Power: Max 350W Tone Control: Learn More Douk Audio VU3 PRO Amp/Speaker Switch 2-Way Amplifiers Max 350W Review: Impressive performance for such a small and reasonably priced amp! - This is a review of the Douk Audio ST-01 PRO 200W Bluetooth Amplifier. I am a low grade audiophile by my own description--I have spent quite a bit of time listening carefully to the same few tracks on a whole range of components over the last 25 years or so. Engineering background so I take a very pragmatic approach--if I can hear a difference myself then I will consider the costs for better gear across the board. I can't blow money on anything and I don't like to be wasteful so I do a fair bit of research before I buy. This little Douk tube amp has really impressed me! I had an old Denon AVR-5700 home theater receiver that had been demoted over the years to just providing sound for our computer--headphone jack outlet from the computer into the receiver, two passive NHT SB-3 speakers driven by the Denon receiver, and subwoofer line out to one passive NHT W2 subwoofer driven by a dedicated NHT amp. When the Denon died, I needed something to power the same speakers and sub but that's it, just 2.1 channels of sound and not audiophile quality to the Nth degree. There are a whole bunch of these tiny devices out there, I liked this one for its combination of price point, tubes for the two speakers, and subwoofer line out to go to my same NHT dedicated amp for the subwoofer. The size is quite amazing, others have shown the same sort of big ol' receiver that was replaced by this tiny cube--it's really just 4.5"W x 3"H x 6.5"D (from the wall to the front of the dials after I have all the connectors installed). The audio power is also impressive. The claims of 200 W/channel are debatable (another review has very solid points about the power supply and the output claims) and that also will depend on what speakers you are using, where their Ohm ratings will influence the power output. Our computer is in a modest home office sized room, about 10'x12' or so, my two SB-3 speakers are 8 ohms being driven directly by the Douk amplifier via the speaker terminals, and the subwoofer is using the 3.5mm line out to the sub amp, so this little device IS powering my speakers but NOT my subwoofer. When I set it up and started testing with my same old tracks, made some adjustments between the volume on the computer and the volume dial on the Douk, I found that this tiny box can rock this room just fine! I'm impressed with how much bass the Douk pushes to the speakers, which have a very good frequency range themselves, which is nice for most musical circumstances anyway where bass guitars, deeper drum beats, and lower ranges in classical performances get very nicely reproduced. The tone adjustment dials on the Douk are quite nice, recognizing that they are just the two simple dials for bass and treble, so I don't expect them to get any more complicated than that anyway. Between the digital equalizer window on my computer which has 12 bands to work with and the two dials on the Douk, there is quite a bit of refinement you can make to match your personal preference for the types of music you listen to and which parts of that music you prefer to dampen or boost. It's basic but it works well. Like another couple of reviewers, I too received tubes that are much smaller than those shown in the photos on the desertcart product page. However, with a little research it seems that the smaller tubes are most likely an improvement from those pictured. I don't know exactly what those larger tubes are--the product page does suffer from missing details like which tubes are included--but the ones I received are legit General Electric JAN 5725W tubes with "MADE IN USA" printed on the glass tubes themselves, which are mil spec quality (which means they are made to very high quality standards to be accepted for military purposes, back when the military was still using lots of tubes). These are usually offered as an upgrade set of tubes for this Douk so I don't know what happened there but I believe the smaller 5725's are top quality for this level of device. They sound terrific to my ear so I'm delighted with them. I have read way too many subjectively written reviews of the feel and warmth and crispness and all sorts of other floral terms describing how tube amps sound compared to modern transistor-based amps. I don't have two different devices side by side to switch back and forth against each other with every other part of the system being identical so I can legitimately compare point for point the tube am to a transistor amp. Suffice it to say that compared to all of my other experience with transistor amps over these years, this little tube dude sounds fantastic! I haven't had any tube amps before so I will have to see how it performs over time, with things like burn in and eventual failure being known factors, but I don't have the tube testing equipment to test exactly when those thresholds will be crossed, so I'm just gonna enjoy the sound until I hear something wrong. The little ol' analog levels dial with the meter jumping around is quite charming as well. It does give you some useful information, just a basic glimpse into how much or how little you are pushing the power. That feature is a nice little throwback to those old times of analog stereo gear back in the day. And while all you young whippersnappers giggle, you'll also notice how vinyl albums and record players are booming again. There truly is some meaningful, warm charm to having a little visual dial bouncing along to the music with you while you tap your foot and try to concentrate on whatever important task you were supposed to be working on while you jam out, right? Totally gnarly dude (yep, I was in high school in the early 80's, for better and for worse). I am just using the RCA inputs from the computer so I don't have any comments on the other input types that the unit offers. Based on what specs they have provided in terms of formats and frequency ranges, and on my listening experience now with this unit, I would guess that those other input source feeds should work just as well as the RCA input, but that is just a guess. For the money, I am delighted with this Douk, if the need arises I would happily buy another one. Hope that's a helpful review, and hope you get to enjoy your favorite music again like I am! Review: This adorable amp punches hard above its weight. - This adorable little puck is incredible. Set it up with some mid bookshelf speakers like the Polk T15's, and a small but potent sub like the BESTISAN Powered Subwoofer, 6.5'' Side Firing Home Audio Sub; you will have an incredible sounding setup. It will not be loud, but it will amaze you for the price. I use it mostly with my home mac via USB on Spotify with the lossless audio setting. So good you guys. You’ll need some speaker wire and a good long 1/8 inch plug audio cable to put the sub exactly where you want it. I have had a lot of high-end audio setups for many years, and I will tell you that for music alone this relatively low-cost one has impressed me more than any other. Plus, the analog glow of the beautiful VU meter and the solid-feeling knobs on this little guy are just incredible. I love it. 9.5 stars, only knock is no headphone jack which is something I don't need. ## Features - Full Upgraded Version of ST-01: 1. Supports U-disk input to play lossless formats music. 2. Add sensitivity adjustment of VU meter on its bottom, easy to set and match better with different input signals. 3. Add three decorative golden circles around tubes and VU meter, looks more exquisite and luxury. - Unique and amazing combination: With VU meter into whole in such a mini size, the pointer dancing in the warm light with strong vintage feelings when enjoy HiFi music, dynamically decorates the audio system space. - HiFi clear sound with tone control: resonable circuit and concise wiring, adopts vacuum tubes to soften the sound and filter out the digital feelings, sounds warm and sweet without noise. Also with treble and bass knobs to adjust one's own preferable sound styles, presents HiFi music with rousing highs and deep lows. - Strong output power and special AUX output: use TI's classic power amp IC, each channel can output 100W(4Ω) and easily to drive all 3-8Ω passive speakers, adds 3.5mm AUX output easy to connect another amplifier or active speaker / subwoofer to build multiple channel system and enjoy wonderful home theater experience. - With multiple digital audio inputs: Bluetooth 5.0 / USB / Coaxial / Optical / stereo RCA, compatible with most audio device such as phones, computers, tablets, TVs, TV, CD players etc. The perfect combination of DAC and amplifier, very suitale for audiophiles who have various audio devices. ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B0BBRBWW36 | | Best Sellers Rank | #27,741 in Electronics ( See Top 100 in Electronics ) #135 in Audio Component Amplifiers | | Brand | Douk Audio | | Brand Name | Douk Audio | | Customer Reviews | 4.4 out of 5 stars 479 Reviews | | Item Dimensions | 4.53 x 3.84 x 2.13 inches | | Item Weight | 1.33 Kilograms | | Item dimensions L x W x H | 4.53 x 3.84 x 2.13 inches | | Manufacturer | Douk Audio | | Material Type | Glass, Metal, Plastic, Electrical Components | | Maximum Supply Voltage | 30 Volts (DC) | | Minimum Supply Voltage | 18 Volts (DC) | | Model | ST-01 PRO | | Mounting Type | Freestanding | | Number of Channels | 2 | | Output Power | 100 Watts | | Part Number | ST-01 PRO | | Specification Met | FCC | ## Product Details - **Item dimensions L x W x H:** 4.53 x 3.84 x 2.13 inches - **Manufacturer:** Douk Audio - **Maximum Supply Voltage:** 30 Volts (DC) - **Minimum Supply Voltage:** 18 Volts (DC) - **Voltage:** 18 Volts (DC) ## Images ![ST-01 PRO 200W Bluetooth Amplifier, 2 Channel Vacuum Tube Power Amp with USB DAC/Coaxial Optical Inputs/VU Meter/Treble Bass Control for Home Theater/Stereo Speakers (Upgrade Version) - Image 1](https://m.media-amazon.com/images/I/71ZB8jMWbDL.jpg) ![ST-01 PRO 200W Bluetooth Amplifier, 2 Channel Vacuum Tube Power Amp with USB DAC/Coaxial Optical Inputs/VU Meter/Treble Bass Control for Home Theater/Stereo Speakers (Upgrade Version) - Image 2](https://m.media-amazon.com/images/I/81Bsw8S64LL.jpg) ![ST-01 PRO 200W Bluetooth Amplifier, 2 Channel Vacuum Tube Power Amp with USB DAC/Coaxial Optical Inputs/VU Meter/Treble Bass Control for Home Theater/Stereo Speakers (Upgrade Version) - Image 3](https://m.media-amazon.com/images/I/81MpIja6hdL.jpg) ![ST-01 PRO 200W Bluetooth Amplifier, 2 Channel Vacuum Tube Power Amp with USB DAC/Coaxial Optical Inputs/VU Meter/Treble Bass Control for Home Theater/Stereo Speakers (Upgrade Version) - Image 4](https://m.media-amazon.com/images/I/81TRLOXO+JL.jpg) ![ST-01 PRO 200W Bluetooth Amplifier, 2 Channel Vacuum Tube Power Amp with USB DAC/Coaxial Optical Inputs/VU Meter/Treble Bass Control for Home Theater/Stereo Speakers (Upgrade Version) - Image 5](https://m.media-amazon.com/images/I/71NHF5Y1W4L.jpg) ## Questions & Answers **Q: What upgrades does the PRO version offer?​​** A: The upgraded ST-01 PRO adds U-disk input for lossless formats, adjustable VU meter sensitivity for signal matching, and decorative gold rings for a premium look. Enhances usability and aesthetics. **Q: How does the VU meter improve my setup?​​** A: It dynamically dances to music under warm lighting, creating vintage vibes and enhancing room decor. Perfect for immersive HiFi experiences. **Q: Can I customize the sound output?​​** A: Yes! Use treble/bass controls (±6dB) and vacuum tubes to warm audio, eliminating digital harshness. Ideal for personalized, sweet-sounding HiFi with deep lows and clear highs. **Q: What speakers work with this amplifier?​​** A: Drives all 3-8Ω passive speakers with 200W total power. Includes AUX output for connecting subs or additional amps, enabling easy multi-channel home theater setups. **Q: Which devices connect to its inputs?​​** A: Compatible with phones, PCs, TVs, and more via Bluetooth 5.0, USB, coaxial/optical, or RCA. Supports high-res audio up to 192KHz/24Bit for audiophiles. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Impressive performance for such a small and reasonably priced amp! *by B***N on November 12, 2025* This is a review of the Douk Audio ST-01 PRO 200W Bluetooth Amplifier. I am a low grade audiophile by my own description--I have spent quite a bit of time listening carefully to the same few tracks on a whole range of components over the last 25 years or so. Engineering background so I take a very pragmatic approach--if I can hear a difference myself then I will consider the costs for better gear across the board. I can't blow money on anything and I don't like to be wasteful so I do a fair bit of research before I buy. This little Douk tube amp has really impressed me! I had an old Denon AVR-5700 home theater receiver that had been demoted over the years to just providing sound for our computer--headphone jack outlet from the computer into the receiver, two passive NHT SB-3 speakers driven by the Denon receiver, and subwoofer line out to one passive NHT W2 subwoofer driven by a dedicated NHT amp. When the Denon died, I needed something to power the same speakers and sub but that's it, just 2.1 channels of sound and not audiophile quality to the Nth degree. There are a whole bunch of these tiny devices out there, I liked this one for its combination of price point, tubes for the two speakers, and subwoofer line out to go to my same NHT dedicated amp for the subwoofer. The size is quite amazing, others have shown the same sort of big ol' receiver that was replaced by this tiny cube--it's really just 4.5"W x 3"H x 6.5"D (from the wall to the front of the dials after I have all the connectors installed). The audio power is also impressive. The claims of 200 W/channel are debatable (another review has very solid points about the power supply and the output claims) and that also will depend on what speakers you are using, where their Ohm ratings will influence the power output. Our computer is in a modest home office sized room, about 10'x12' or so, my two SB-3 speakers are 8 ohms being driven directly by the Douk amplifier via the speaker terminals, and the subwoofer is using the 3.5mm line out to the sub amp, so this little device IS powering my speakers but NOT my subwoofer. When I set it up and started testing with my same old tracks, made some adjustments between the volume on the computer and the volume dial on the Douk, I found that this tiny box can rock this room just fine! I'm impressed with how much bass the Douk pushes to the speakers, which have a very good frequency range themselves, which is nice for most musical circumstances anyway where bass guitars, deeper drum beats, and lower ranges in classical performances get very nicely reproduced. The tone adjustment dials on the Douk are quite nice, recognizing that they are just the two simple dials for bass and treble, so I don't expect them to get any more complicated than that anyway. Between the digital equalizer window on my computer which has 12 bands to work with and the two dials on the Douk, there is quite a bit of refinement you can make to match your personal preference for the types of music you listen to and which parts of that music you prefer to dampen or boost. It's basic but it works well. Like another couple of reviewers, I too received tubes that are much smaller than those shown in the photos on the Amazon product page. However, with a little research it seems that the smaller tubes are most likely an improvement from those pictured. I don't know exactly what those larger tubes are--the product page does suffer from missing details like which tubes are included--but the ones I received are legit General Electric JAN 5725W tubes with "MADE IN USA" printed on the glass tubes themselves, which are mil spec quality (which means they are made to very high quality standards to be accepted for military purposes, back when the military was still using lots of tubes). These are usually offered as an upgrade set of tubes for this Douk so I don't know what happened there but I believe the smaller 5725's are top quality for this level of device. They sound terrific to my ear so I'm delighted with them. I have read way too many subjectively written reviews of the feel and warmth and crispness and all sorts of other floral terms describing how tube amps sound compared to modern transistor-based amps. I don't have two different devices side by side to switch back and forth against each other with every other part of the system being identical so I can legitimately compare point for point the tube am to a transistor amp. Suffice it to say that compared to all of my other experience with transistor amps over these years, this little tube dude sounds fantastic! I haven't had any tube amps before so I will have to see how it performs over time, with things like burn in and eventual failure being known factors, but I don't have the tube testing equipment to test exactly when those thresholds will be crossed, so I'm just gonna enjoy the sound until I hear something wrong. The little ol' analog levels dial with the meter jumping around is quite charming as well. It does give you some useful information, just a basic glimpse into how much or how little you are pushing the power. That feature is a nice little throwback to those old times of analog stereo gear back in the day. And while all you young whippersnappers giggle, you'll also notice how vinyl albums and record players are booming again. There truly is some meaningful, warm charm to having a little visual dial bouncing along to the music with you while you tap your foot and try to concentrate on whatever important task you were supposed to be working on while you jam out, right? Totally gnarly dude (yep, I was in high school in the early 80's, for better and for worse). I am just using the RCA inputs from the computer so I don't have any comments on the other input types that the unit offers. Based on what specs they have provided in terms of formats and frequency ranges, and on my listening experience now with this unit, I would guess that those other input source feeds should work just as well as the RCA input, but that is just a guess. For the money, I am delighted with this Douk, if the need arises I would happily buy another one. Hope that's a helpful review, and hope you get to enjoy your favorite music again like I am! ### ⭐⭐⭐⭐⭐ This adorable amp punches hard above its weight. *by M***G on March 12, 2026* This adorable little puck is incredible. Set it up with some mid bookshelf speakers like the Polk T15's, and a small but potent sub like the BESTISAN Powered Subwoofer, 6.5'' Side Firing Home Audio Sub; you will have an incredible sounding setup. It will not be loud, but it will amaze you for the price. I use it mostly with my home mac via USB on Spotify with the lossless audio setting. So good you guys. You’ll need some speaker wire and a good long 1/8 inch plug audio cable to put the sub exactly where you want it. I have had a lot of high-end audio setups for many years, and I will tell you that for music alone this relatively low-cost one has impressed me more than any other. Plus, the analog glow of the beautiful VU meter and the solid-feeling knobs on this little guy are just incredible. I love it. 9.5 stars, only knock is no headphone jack which is something I don't need. ### ⭐⭐⭐⭐ Still sounds good 18 months later *by A***R on February 20, 2025* Sounds pretty good out of the box and can be upgraded with better tubes, external DAC, etc. I have a dozen other amps including the Fosi ZA3, vintage Kenwood and Marrantz, AVRs from Cambridge, Denon, Yamaha, NAD. The built-in DAC isn't great so I use an external DAC that I prefer, it's just the old $20 FIIO Taishan. I go optical out from my TV into the FIIO DAC and then RCA analog into the Douk preamp/amp, which is powering a pair of vintage ADS bookshelf speakers. Recently tried it with my SMSL SU-1 DAC and that was even better. Needed a small form factor to fit the space. Been using it for 18 months, with no issues. The tubes definitely change the sound. It's fun to experiment with different tubes and they're readily available on eBay, often for $20-30 or so for a matched pair. Everyone on Amazon gets the Riverstone Audio JAN 5654W tubes that are marketed as an "upgrade" but I didn't really care for them. Sounded dull and rolled off to my ears. I prefer old soviet-era Voshkod "rocket" tubes. They have a more dynamic hifi sound with extended highs and lows. The VU meter doesn't work very well for me (maybe by speakers are too small/efficient to move the needle at regular listening volume?) but that's kind of a gimmick anyway. Overall worth it for the tube preamp and TI class-D amplifier functions that I use it for. This can be a good option if you like tubes or want to try them out. Also good if you need the digital inputs and Bluetooth built-in, as those are usable if not the greatest. ## Frequently Bought Together - Douk Audio ST-01 PRO 200W Bluetooth Amplifier, 2 Channel Vacuum Tube Power Amp with USB DAC/Coaxial Optical Inputs/VU Meter/Treble Bass Control for Home Theater/Stereo Speakers (Upgrade Version) - Banana Plugs with Dual Set Screws,Black and Red Aluminum Shell,6 Pairs --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.sk/products/473216135-st-01-pro-200w-bluetooth-amplifier-2-channel-vacuum-tube](https://www.desertcart.sk/products/473216135-st-01-pro-200w-bluetooth-amplifier-2-channel-vacuum-tube) --- *Product available on Desertcart Slovakia* *Store origin: SK* *Last updated: 2026-05-24*