XDUOO TA-66 High-Performance Tube Amplifier

If you own the HD800S and want to explore tube amps, I wouldn't walk but run to try this. I previously used the Massdrop x Eddie Current ZDT Jr but decided to buy this amp based off a recommendation on the Super Best Audio Friends forum. After comparing the two, I sold the ZDT Jr and kept this amp as I enjoyed the sound of it more in comparison. Compared to the ZDT Jr, this amp's bass impact is noticeably stronger, fixing what I always felt was the HD800S’s biggest weakness. But, the trade off is a slightly smaller soundstage, and for me, that’s okay. Treble is also slightly rolled off which helps with the HD800S' second weakness which is sibilance. The overall sound with this amp is smooth and impactful. There are two downsides to this amp. First is that the power button is in the back of the amp. It's a minor inconvenience to have to reach to the back to turn it off and on but I can live with it. Second is the humming. If you're experiencing humming, I would check to see if it's caused by the front tube. In my case, tapping the front tube with a remote control permanently fixed the problem (similar to fixing old TV static back in the day by tapping the TV). Your mileage may vary, but it’s worth trying before assuming the amp is defective. Despite the inconveniences, given the price, I would highly recommend this amp. If you’ve been searching for a budget amp to pair with the HD800S, this could be your endgame honestly. I've previously owned the Schiit Magni, Cavalli Audio Liquid Carbon (remember that amp?), and the Massdrop x Eddie Current ZDT Jr and this amp blows all of them out of the water.

UPDATE: The seller and manufacturer took a fast response and sent a second unit, which is working perfectly well. Noise floor is acceptably low and the sound impact is amazing, I use this unit as a preamp/buffer for a small JLH1969 2x15W Class-A solid state amp, the combination not only has full bass but also very clear and defined mids and non-fatiguing highs. Overall I am very satisfied. PREVIOUS: When I power on the amp, the transformer immediately start making a loud buzzing/humming sound that can be heard across the room. If I connect it as a preamp, the same noise is audibly amplified by my power amplifier, resulting in a very disturbing bottom noise. Although it colors the sound the way I wished it would, making the soundscape more vivid and with fuller bass, I don't think I can use this item with the constant hum it generates.

Great sounding amp! I've tried many different amps and headphones and this one absolutely holds it's own in terms of value and sound.

Amazing quality for the price point. I connected this to the TAPE OUTPUT of my vintage Japanese solid-state receiver to act as a dedicated headphone amp for my record player. My Sennheiser 6XX's have never sounded so good.

No complaints. All the way from China in just 10 days. Much better separation and depth. Softened vocal consonants. Completely enlivened all forms of audio. What a bargain at just $219. I am a big tube fan now. Experiential update: Operating on the theory that more good is even better, I cranked the gain on this baby past 50% to 100% and the audio became unpleasantly distorted. Then I recalled that the theory of tubes is that they make the sweetness by distorting “pleasantly”. More distortion does not equal more pleasantness but merely distortion. So I experimented and concluded that 50% is sweet and more is not. Still love it!

Great little amp, nothing like the distinguished tube sound. Smooth and a tiny bit mellow. Make sure you use fairly high impedance headphones. To be honest I probably would have gone with a different amp by this company that would work with a larger amount of different headphones. My 38 ohm Denons will not work with this but my 300 ohm Senheiser HD660s cans sound beautiful through this amp. I’ll be using this amp for years to come, with the streamer and DAC I am using to feed it.

I've owned all sorts of much more expensive tube and solid state headphone amplifiers. As far as my HD800S and HD600 are concerned, this sets the bar. Very quiet for a tube amp. Virtually zero hum or hiss from day one. What was barely audible early on has now completely disappeared after the first couple dozen hours of listening. In my experience, finding a truly QUIET tube amp has been a challenge. With this quietness comes a level of clarity and detail retrieval that is truly impressive when combined with that sound staging and dimensionality that only tubes can provide. Highly recommend trying this one if you're new to this hobby, or even if you have lots of prior experience like myself. Send it back if it doesn't manage to impress.

Please don’t pay attention to the negative comments in the reviews. I just purchased this amplifier January, 2024. First it’s a fantastic machine the sound is the best I have ever heard. You need a pair of headphones of at least 300 ohms or better to get the sound you are looking for. I use a pair of Sennheiser HD600s. The sound is fantastic. I also used a pair of Kali UP-UNF speakers and they pair perfectly. It’s created a level of sound quality that keeps you listening for hours and hours. I can’t recommend this amplifier, Speakers, and Headphones enough. All are available on Amazon at a good price. Headphones.com wants 449.00 currently for the HD600s while Amazon has them for 314.00. Speakers are 299.00, and the amplifier is 229.00. Don’t know how long these prices will last of President Trump has his way with the tariffs so don’t wait before you see the price jump drastically higher. I am just a music lover like you who choose to point out fantastic products hoping to help others obtain a better experience with music.

First of all, I want to mention that I am not even remotely an audiophile in the usual sense of the word, but I like to listen to all genres of music in the best possible conditions and according to my preferences. I'm driving this "little" baby with a FiiO K11 R2R DAC/ Headphone Amp, over the Line Output. It is a sensible difference between the sound directly from the Fiio or through the TA-66. The Xduoo TA-66 is an excellent headphone amplifier that has completely transformed my listening experience with my Beyerdynamic DT 990 Edition Pro 600-ohm headphones. This combination brings out the absolute best in my music, and I couldn’t be more impressed. The TA-66 is a work of art. Its robust construction and elegant design exude quality. The glowing tubes not only add a classic aesthetic but also hint at the warm, analog sound it delivers. The volume knob is has strong clicks when you rotate it. The TA-66 drives the 600-ohm DT 990 effortlessly. The amplifier provides ample power, allowing these demanding headphones to shine. The soundstage is incredibly expansive, creating an immersive listening environment where every instrument and vocal has its space. The detail retrieval is simply astonishing. With the TA-66, I hear nuances in my favorite tracks that I never noticed before. The bass is tight and controlled, the mids are lush and natural (maybe a little bit recessed, as I like), and the trebles are airy and crisp, complementing the DT 990's signature sound. The TA-66 is not just a powerhouse but also very versatile. The gain adjustment in 24 steps, allowinga good control over the volume. Tube rolling may be an exciting option for those who want to tweak the sound even further, but in my opinion, the stock tubes already deliver an outstanding experience. For the price, the Xduoo TA-66 is an absolute steal. It competes with amplifiers that cost significantly more and often outperforms them in terms of sound quality and build. It’s a perfect match for high-impedance headphones like the DT 990, and the synergy is magical. If you own a pair of high-impedance headphones, the Xduoo TA-66 is a must-have. It delivers an unparalleled combination of detail, warmth, and power that transforms your music into a breathtaking sonic experience. I cannot recommend it highly enough!

Super ampli à lampes, très bon rapport qualité/prix, chaudement recommandé.

Phenomenal for the price !!

Ottimo apparecchio, costruito davvero bene, (potenziometro/attenuatore di potenza a scatti e può essere usato anche solo come preamp) e ciò che conta di più, molto ben suonante, (onestamente mi meraviglio per il costo) perfetto sopratutto per cuffie ad alta impedenza ma per farvi capire cercherò di darvi dei riferimenti, ho pilotato Beyerdynamic dt770pro e dt880 entrambi 250ohm con potenziometro a ore 11.00, zero distorsione suonano pulite, dettagliate, scavando ed evidenziando sub e bassi senza difficoltà insomma ottime, Beyerdynamic dt770pro X 48ohm (cuffie abbastanza efficenti) a ore 11.00 sempre zero distorsione suonano molto bene nonostante l'ampli sia dato per 60/300 ohm quindi al limite del fattore di smorzamento, (nel web troverete informazioni riguardo questo) con Hifiman HE-R10D 60 ohm a ore 11.00, come sopra (ottime), AKG K702 62ohm (questa non essendo molto efficente, in generale è abbastanza ostica da pilotare) ha suonato come deve, senza esitare, infine Hifiman Sundara Closed che ho acquistato poco tempo fa, 20ohm (le planari normalmente non sono l'ideale con amplificatori valvolari) a ore 14.00 ZERO DISTORSIONE (e lo sottolineo) abbastanza bene ma perdono un po' di definizione nelle sub e nelle basse, le preferisco con i due stato solido, Lake People G109 e G103Mk2, (altra cosa non meno importante, tutto ciò con ZERO rumore di fondo, aggiungo che sicuramente non è un ampli con cui ci pilotate di tutto, e ci mancherebbe...per questo dovreste spendere almeno 3/4 volte questa cifra se volete un valvolare definitivo, in più se parliamo di connubio ampli/cuffie/suono qui diventa tutto soggettivo, proseguendo con Grado SR325x e Alessandro Grado MS1-X entrambi a 38 ohm invece non ci siamo, secondo me perdono qualità, suonano meglio con lo stato solido (probabile che qui entri davvero in gioco il limite di questo apparecchio)...ma non si può avere tutto...ora non voglio assolutamente muovere critiche verso altri utenti, è solo un mio pensiero, leggo di persone che dichiarano che l'amplificatore in questione non avrebbe volume o potenza... Direi che dipende da che apparecchiatura hanno collegato e a che volume ascoltano la musica...ma tant'è... Cmq ottimo ampli ottimo acquisto, consiglio assolutamente. P.S occhio perché come tutti i valvolari scalda molto!

Superb item, quality build, sound quality is awesome. Very cheap way to get into valve amplifiers - and with an adapter - it opens up to some good tube rolling options.