Gemtune APPJ PA1502A 6N4+6P6P tube headphone amplifier (Black)

I can't say what this would sound like with the stock tubes but with JJ 6L6's and a Gold Lion 12AX7 running into a pair of Audio Technica ATH-M50 headphones, this amp sounds wonderful. It has power and command. Whether I listen to vinyl via a tube preamp or if I'm running it via a bluetooth receiver listening to Sirius XM or YouTube, this amp sounds better than I'd ever thought it would. I also changed the knob to a more knurled type to make it easier for adjusting. It comes with a smooth knob that was difficult for me to adjust with one finger when sitting in my recliner.

This is a great little amp. Sounds good right out of the box, but I put in some nos Ratheon 6v6's from 1958 and a Sylvania 12ax7 from 1961 and it made a huge difference. It would get 5 stars if it had decent tubes. A great buy. I hooked it up to my computer also, and the audio significantly improved, which shows that my computer's sound interface does not handle power well - even the small amount to power headphones. Same with the laptop. I suspect most digital devices are this way. If you buy this do yourself a favor and buy good tubes for it. I'm using it to power regular dynamic over the ear cans - not cheap, not expensive.

This is an outstanding headphone tube amp. I upgraded the original tubes with a Genalex SINGLE Gold Lion 12AX7 ECC83 B759 Tube Gold Pins, and Genalex Factory Platinum Matched PAIR Gold Lion 6V6GT. I'm using an Elfidelity Sound Sourced PCI-E Hifi AK4396 DAC 2.0 Channel Internal Sound Card into a REAL pair of Sony MDR V6's. The warmth and clarity of this amp is amazing and money well spent for up and coming audiophiles.

I've only had a couple of hours on the amp so far but it does sound nice. There was no documentation with the amp but it is simple enough, only line in on the back and a switch, phone plug, and volume on the front. The switch is labeled H and L. I wasn't sure if this was for impedance or gain. My Fidelio X2s are 30 Ohms and worked fine in either position, just much more drive in the H position. I did email Gemtune and asked about the switch, they got back to me promptly and said it was for high or low impedance but didn't say what the switch over point was. At 30 Ohms, I would call my X2s low, but for 150 Ohm, who knows.I did notice some hum when set to high and no audio input, could just be the mismatch. In the low position there is no hum.Even right out of the box with no burn in, the amp sounded fine driven by my iPod. Max volume in the low position was plenty for my ears. In the high position, I could really drive the phones and did not notice any bad behavior ( less the hum, which may change with time on the tubes, and is not perceivable once playing ).The amp has solid brass feet which let it slide around easily. I would have liked rubber feet better but not a big deal.For now I'm just running the tubes that came with the amp.The only reason I give it 4 stars instead of five is lack of documentation

Always blown away by the sound of this amp! The stock tubes are alright, but rolling some different tubes makes drastic changes in sound. I ended up using Genalex Gold Lion 6V6GT for the power tubes and a reissued Mullard 12AX7 for the driver tube. Amazing clarity and black background.

Just received this and couldn't be more happy! Rolled the stock tubes for upgraded electro harmonic and genalex tubes and could not be more pleased! Build quality is great. Amp arrived from China very quickly and well packed! Will likely change the feet, but that is my only quibble so far.

I am no self-proclaimed audiophile, just a hobbyist who loves relaxing sessions of headphone music in my recliner after a long day of work. I have had this amp for 4 years and still impressed by it enough to write a review of recommendation. It might not be as powerful as my Gustard H10, but it's powerful enough to drive all my headphones - dynamics and planars, to satisfaction and they all sound great. It's certainly a winner in looks with those bottle Tung-sol KT66 tubes. Always a great conversation piece for anyone who sees it for the first time.

真空管ヘッドホンアンプの手ごろな品物がほかになかった、ということや、わたしの保有しているヘッドホンをきちんと鳴らすことができる、という点で購入してみました。上流は、　　　Raspberry Pi （moOde）→ES9028 DAC→本機下流のヘッドホンは、　　　・ATH-AD900X, audiotechnica　　　・K701, AKG　　　・DEVA, HiFiMAN　　　・T60RP, Fostex気分によって使い分けしています。いずれも変な味付けなく、「普通に」音を楽しむことができています。真空管特有の「柔らかさ」「艶加減」はちょっとわかりませんが、良い音です。(*^^*)

Brilliant headphone amplifier......those clever little valves......they really help. Build quality good. Overall sound quality is very good, detailed, clean, good bass. Very pleased.

CDレシーバーにRCA接続して聞けるヘッドホンアンプを探して本品を購入してみました。標準装備の真空管（6N4+6P6P）では、少し柔らかくも音がボヤけ気味の音だったので、別途購入した、12AX7+6V6GTに換えてみたところ、余韻を引きながらもはっきりとした音に変わり感動を覚えました。自分の好みにあった真空管を探求したり、曲に合わせて真空管を換えて見るのもいいかもしれません。注意点としては、使用中、使用後は真空管がかなり熱くなるので取扱に気をつける必要があります。

The package arrived within 7 days. The device was properly packed and mounted, no signs of damage or bad handling.The amp comes without a power cord: you need a standard UK cord, same as for most computer monitors or most PC power supplies. If you plan to connect it to a smartphone or mp3-player or any other player with 3.5mm headphone jack you also need a 3.5mm to cinch connector, check the pictures on the Amazon page and you will see what you need. Depending on the headphones you want to use you also may need a 3.5 to 6.3mm headphone jack converter; earphones have plugs that wouldn't fit; many headphones either.The device comes mounted, but the tubes weren't put in tidily; some sort of tower of Pisa mount ... this can be easily fixed: If you never have done this take a cloth and correct the positioning. The power tubes need a little more force than the small one in the middle. Avoid touching the tubes with your fingers.The design is quite appealing, I may call it "cute", and the amp is solidly assembled. The socket plate on the back for the power supply has some slack, but that is ignorable. The volume knob is not the best quality, but it allows to tune the volume very finely. I have not tried it, but it shouldn't be difficult to replace the knob by a better one.Don't expect too much "glow-in-the-dark" beauty. The heater wires of the power tubes are mostly covered by a black metal cover, and these tubes sit a quarter or more in sockets -- You hardly see more than the tip of the heater wire. The smaller central tube contributes more to the visual pleasure of having a tube-amp. However, whereas overall I think this amp is smartly designed, the power switch on the back has a built-in lamp. When switched on that lamp produces more illumination than the tubes, and what's worse, it's asymmetrical - the switch on the back is on the left side. It has a bit of the sobering effect you get from advertisements during a gripping movie. If anybody from the company that builds this amp is listening: please change this switch against one without a lamp! The lamp is of no use anyway - if it's on we hear it .. (Alternatively one could probably over-paint the switch as it is on the back of the device; or open the sesame and use more destructive measures ... )For the report below I used the amp with an average mp3-player and Sennheiser HD265 headphones which, even though not the newest, are pretty good quality. They have an impedance of 160Ohms. This is more towards the higher end.The little switch on the front is for changing between low- and high-impedance headphones; low-impedance ones are between 4 and 32 Ohms - this has nothing to do with quality, high impedance can be 600 Ohms, check what you have. The HD265 can be used on both settings but the sound properties are clearly different. The following may differ for your particular set of headphones.On the low setting the loudness is considerably lower than on high, but good enough unless you want it really loud; this is to be expected given that the high-impedance phones match the output of the amplifier better. For low-impedance headphones it should be the other way round (haven't tried).There is a some hum at high amplification during silent periods. In the low impedance setting this is almost neglectable throughout; in the high setting it is clearly present in about 20% of the upper loudness range (your ears may be better or worse than mine). The hum does not have an effect on experience when the music is playing, only during the pauses.In both settings, low and high, the middle frequencies are pretty good and transparent. In the low setting the bass is a bit dominating and the highest frequencies seem to be under-represented. This is better in the high setting, where the low, middle and high frequencies are more balanced. However, in that setting you have the hum in the pauses at high volume.I'd say for some sorts of music, black-key classics, mellow jazz, sad-sad ballads .. and the like beauties, I'll be using the low noise-free warm setting and for others, Rock, Hip-hop, D&B I'd be using the high setting (D&B works actually quite well). Only the latter setting would allow for enough loudness to destroy your inner hear cells, i.e. your hearing capabilities.The "tube sound" ... yes, it's there. The sound is "warm" and there are practically no saturation effects. There was one very short cracking noise while I tested, as if of an an arc in the electronics - I'll have an ear on that. Slightly scary.The sound could be more transparent. It is more so in the high setting, but compared to the studio speakers I mostly use transparency lacks. Still, listening to music going through this amp is not tiring; you just don't hear all that is there.Remember your experience can be very different depending on what headphones and sound source you use, and your state of mind.The price of the amp is quite ok, if you want a tube amplifier. It would be challenging to build it cheaper from scratch at least if you take work hours into account. If you just want a headphone amp, a silicon based one would be more cost-efficient.Some other reports mention quite enthusiastically that using other tubes improves the sound quality of this amp. I'd be sort of tempted to try, but all I have lying around are some dual triodes from old radios that may fit. Anything else would be a further investment ..Thanks for listeningT