This review is written from the perspective of an audio enthusiast who has had significant experience with tubed equipment over the years. It is considered from the perspective of its performance within its price point as an "integrated" amp that provides control functions in a unit with a tubed driver stage and solid state (operational amps?) output - therefore "hybrid" designation. Context for this review was 16 ohm speakers in a desktop - office system driven by Windows-based machine through a professional audio interface - and Bluetooth streamed from an iPhone 6.

First the negatives: The "25 watts" is "peak power" output. This specification is rarely, if ever, used by audio component manufacturers. If you look closely the "RMS" output it is "15 watts" into "a 4 ohm" load.

Many speakers available present an 8 ohm load, and most amplifier companies will express "RMS" power into 8 ohms which divides the actual RMS power of this amp (rated into 4 ohms at which time it reaches its stated level of distortion) by half or approximately 7-8 watts - if you were to compare it to other amps using a RMS into 8 ohm load. Now, that being said, its the first watt that is important and this unit does that very well. 7-8 watts for a desktop, office, bedroom or dorm-room system is more than enough.

Secondly, the power switch is clunky and mechanically scratchy when actuated. It does not inspire confidence in terms of long-term reliability. This "problem" stands out ironically because the rotary knobs are wonderfully silky, with nice resistance and not at all what I would expect at this low price point - in a good way.

Finally, like others, I could not completely remove the protective plastic from the "vu meter" there is some residual still stuck under the bezel that I won't attempt to remove for fear of causing more harm than good. This is a petty aggravation.

Now for the reason to buy this unit: the sound! Used within limits, it renders mid-range (voice, acoustic guitar, etc.) with amazing detail, dynamics and tone color. I'm listening to the amazing guitarist Michael Hedges (streamed online music service 16bit-44.1khz) while I type. The qualities of his amplified and effects-affected Martin come through clearly with good rhythmic drive and the delicate characteristic tone "color" associated with his Martin. Truly amazing for this price point!

Extreme highs and lows do not hold up quite as well, but I ascribe to the belief of "get the mid-range right and everything else will fall into place". Do not expect headbanging, Skrillex or Metallica to hold up well. Overdirive the unit and it flattens out losing much of its tone color and dynamics.

Headphone listening came with the same positive benefits mentioned earlier.

I did limited listening Bluetooth with mixed results. (iPhones earlier than 6s do not take full advantage of the AptX wireless streaming, so I cannot fairly comment.) Some music sound great as if coming right off the digital interface other music sounded very limited and grainy like most MP3 or MP4A out of the box where cymbals sound like peas rolling in a tin can - sorry. I think its more of a "format" problem.

Overall, a well designed execution. Monoprice does not need to inflate the power spec, this unit sounds absolutely wonderful when operated within its limits.

This product is musical, amazing at this price point and highly recommended as a desktop, bedroom, dorm-room music player.







PROS: Sound quality - a glimpse of tube heaven

Affordable and easy to find replacement tubes

Great "desktop" and headphone amplifier

Amazing value

CONS: "25 watt" naming is modestly deceptive

Clunky power switch

Plastic protective covering on "VU METER" impossible to completely remove

Volume does not completely mute signal through CD source

Looks good, has a good girth and streaming Pandora via the BT was surprisingly satisfying. I paired it with a set of Wharferdale Diamond 7.1 and it was a good match. Interesting to note, streaming via my iPad produced a fuller playback than using my Note 3 both with Pandora.

The bad, in ascending order:
My refurb unit had an occasional light hum, but it could only be heard if you weren't playing something. Non-issue for me, but for some, this could be a problem.
Clips at half volume. But this was setup for a bedroom, so the output was acceptable.
The right channel kept going out. I tried different speaker cables and cleaning the terminals, but no joy

Note:
I could've sworn that the unit had a 30 day, money back guarantee, but MonoPrice is only offering me a store credit.

PROS: If not for the failure of the right channel, I would've been singing the praises of this amp

CONS: Clipping at half volume and failure of the right channel

Smoke and burning smell came out of nowhere 0ne night resulting one the of the speaker terminals not working - all in just 6 months of very little use (a few hours a week on average). Before this, low pitch interference can be heard from the speakers, but I accepted / got use to it. It was not very noticeable when volume was louder and when the bluetooth paring device (my phone) was closer standing next to tube amp. I have send an email to Monoprice asking for warranty but have not got a response. Don't recommend it because, in my experience, the speaker terminal problem is common.

PROS: Sound good, simple and easy to pair up. Doesn't take up much space and look good.

CONS: Broke in 6 months of little use. No more sound from one of the speaker channel.

My husband was really looking forward to this for his birthday and when it arrived the amp would make cracking and popping noises when playing music. We requested a replacement and when we finally received that one it had the exact same problem. So either the merchandise is being manufactured poorly or they sent the same one back. Either way, I'm not buying from them again.

Bought the unit in mid November of 2015. Easy to set up my 2015 Mac Pro connected via bluetooth immediately. Made my KLH speakers sound the best they had in years. Was really happy with the purchase.

However - of course there is a however - in the last month problems have started to develop with the amp. The bluetooth will stutter after an hour or so of use. Mostly it just drops audio for a second at a frequency of around two minutes, but every now and then it disconnects completely then reconnects to the Mac Pro with a "your phone is connected" message. Turning the amp off for a few minutes then back on will make the problem go away... for an hour or so. I've turned off the BT on my phone and tablet, to no avail.

To get around this I plugged in a cable from the Mac Pro to the CD inputs on the back of the amp. No good within seconds a background hum starts that builds in volume past any comfort levels. This is the same cable and sound port on my Mac I used for my old amp, so I don't think that's the problem.

Then the power button fell off.

Based on other reviews it appears the unit quality is hit and miss. Mine missed.

PROS: Full bodied sound

CONS: Bluetooth problems, growing background hum for cabled input, quality of parts

This is a great little amp. It's gorgeous, with it's glossy black case, brushed metal faceplate, and warm glowy tubes and VU meter. And it sounds lovely. I haven't really cranked it up hard yet, but it does an admirable job of driving the pair of Fluance SX6 speakers on my desk. I can hear a bit of a hum through my speakers when nothing is playing (and I'm powering this through my big UPS, so it's not a bad ground). I just shut it off if I'm not listening to anything anyway, so no big deal.

Sounds awesome, looks to match. If you're looking at this, it's because you want one just buy it and start enjoying your music again.

PROS: warm tube sound, great looks, well packaged, incredible value, simple Bluetooth connectivity.

CONS: gloss black shell can show finger prints (so stop touching it!)

tubes get warm (as expected so let the thing breath and don't touch em!)

has a bit of a hum

When I unpacked it I was amazed at the build quality and looks. It came well packed with tubes in place. Now since this is a hybrid I didn't expect it to fare too well against my tube amps given the low price.. Boy was I surprised.. Nice warm tube-ish sound with a huge soundstage. This is going to be a tube roller's delight.

PROS: - Sound Quality

- Solid build, quality construction

- Attractive looks

CONS: - Side panels fingerprint easiy

This is a beautiful little amp and is extremely well packaged with thick custom foam pieces and double-wall cardboard. Right out of the box, I had it hooked up to my Pioneer Andrew Jones LR22 bookshelf speakers, which seemed a good match. I enjoyed it that was for a few days. Next I put it in place of my main amp and tried my Koss CM1030 4-ways, which are 94dB sensitivity and 5 ohms nominal. This little amp will drive them cleanly to upper-90 dB peaks and 90dB average levels. Bass control is very good and it has a definite tube sound. So far, it has stayed in my main system since as it is fun to listen to. I found some Russian military 6P15 and 6N2s and rolled them in place of the stock Shuguang tubes. It's a bit quieter now and airier, but the sound was quite good out of the box. For the money, this is a fun amp and worth every cent. I can enjoy tube sound without putting hours on an expensive set of quad KT88s in my main amp. I have tried Blue tooth and direct in and the BT works quite well with good sound and range, very near CD quality. The BT certainly won't diminish any MP3 listening. With a 30 day return on this amp, if you are on the fence, just give it a try. It seems like some of the QC problems with parts have been fixed since it was introduced, so it seems that Monoprice listens to customers and also handles returns easilywhich is good considering that any tube gear can take a hit in shipping.

PROS: Compact
Low power consumption
Tube sonics
Bluetooth convenience
More power than with small-signal tubes alone
Fairly portable



CONS: Works most efficiently with ~4 ohm speakers
The "ray gun" rings around the tubes may not be for everyone
Speaker connections don't give much room

I saw similar hybrid amps a couple of years ago, and thought they looked good, but wasn't sure if they were going to be just a passing fad, and resisted the urge to buy another piece of audio equipment. I've been noticing I've been listen to a lot less music lately, just because digital music just doesn't sound that great. Love the convenience of bluetooth, but music just doesn't sound like live music any more. I'm redecorating my cabin, which often becomes the dumping ground for a lot of my spare stuff. I use studio monitors / external computer interface in my house and office, and moved my hpome stereo system there. I decided to upgrade an d pulled the trigger on a new amp. FIrst of all, this amp looks really great. Love the warm light lights of the tubes, so pleasing to look at compared to LED. The sound is spectacular. Compared to my Denon amp, this thing is completely, undeniably, better! Music sounds like music again. Wow. I'm pretty busy, but just wanted to wanted to share my experience for others out there who may have lost enthusiasm about music.

I use a cable from my laptop whenever I can, and bluetooth from phone works pretty well, though not as impressive. However, shockingly better than phone going through bluetooth to a standard amp.

Words of caution though: 20 amps per channel is not a huge amount of power, and i have it turned up almost all the way. My speakers must be about 89 dB sensitivity, and I would be cautious if yours are less than that. Doesn't seem to clip at the top end though.

CONS: rite my experi

Arrived the day after Thanksgiving. Set it up to discover that the right channel was dead, along with one of the vacuum tubes. Two of the remaining three tubes weren't functioning at peak levels, either.



Contacted Monoprice and they were quick to issue an RMA and the bad unit will go back on Monday. Hopefully, a replacement unit will ship soon. I'm looking forward to connecting this to my Bose 141 speakers.



I'm giving a 10-star review because of Monoprice customer service. Outstanding, so far. Once I get a functioning amp, I'll review it based on performance.

PROS: Looks nice, but don't know about the audio quality yet. Monoprice was quick to do an RMA. So I hope to have a replacement amp soon.

CONS: Arrived damaged.