Nobsound Mini Dual TPA3116 Digital Power Amplifier HiFi Stereo Amp Audiophile-Grade 2.0 Channel 100W×2 NE5532P Pre-Amp (Black)

My original order arrived with a damaged power switch. I contacted the company via their website. The same day, they responded to me and shipped a replacement. Wow, outstanding customer service! The replacement is working fine. In fact, it has far exceeded my expectations. I first used it to burn in a pair of MarkAudio full-range drivers. I had the Nobsound running at moderate levels almost 24/7 for two weeks straight. I was concerned that the small heat sink might cause the amp to overheat, but it never got more than slightly warm to the touch. Next, I tried the Nobsound in my spare audio system, where it stomped my B&K ST-202 amp. Then I tried it in my video system, and in some ways I preferred it over my Anthem MCA-30. Compared to these large class-AB amps, the Nobsound class-D amp sounds quicker and more articulate, with better detail and attack. There is no slurring of complicated musical passages. When there is no input signal, the Nobsound is dead quiet even when the volume is turned up all the way. Finally, I did an A/B comparison between the Nobsound and my EL34 tube monoblocks. The Nobsound doesn’t have the same imaging depth or subtle inner texture. But, hey, it’s not a $2,000 unit. I’m amazed that the Nobsound can compete with some pretty respectable audiophile gear.Some additional observations:• Sonically, the Nobsound is a bit on the lean, sterile side. If you like a fat tubey sound, this unit isn’t for you. The soft dome tweeter on my Quad speakers adds some beneficial warmth. Surprisingly, the Nobsound sounds pretty darn good with the MarkAudio Alpair 10.3’s, which aren’t particularly warm.• The resolution of this amp is pretty high, so it reveals whatever you feed it (good or bad). The sound is great with quality recordings, good upstream electronics, and quality cables. I’m having good luck rotating between Anti-Cables, Mapleshade speaker wire, and Kimber 8TC. Silver cables sound too hot, in my opinion.• Remember that you have to provide your own power source. I bought a 24v AC/DC adapter from Amazon. I found that two 12v batteries sound slightly better than wall power, producing somewhat better resolution.• Make sure you insert the power adapter jack into the amp before plugging the AC/DC adapter into the wall. Otherwise, you’ll get sparking when you insert the power jack.• The speaker terminals are spaced really close to each other. It’s best to use banana plugs going into the amp. My cables have large spades, which are almost impossible to attach. It’s likely that the spade tips will touch, possibly causing a short. You can use bare wire, up to about 14 gauge. Again, though, you have to be careful that stray ends don’t touch.UPDATE: I've been using this unit for about 6 months and am still very impressed with the value of the Nobsound. I tried using it with highly efficient horn speakers: JBL 2445J @ 111 Db efficiency. The speakers reveal all sorts of noise from the recording, but between tracks there is dead silence. I can turn the volume up to the 12 o'clock position before I hear some slight hum from the amp. That's way higher than my normal listening level. With the volume at 12 o'clock, I'd be blasted through the back wall!

This looks to be a very well-built mini-amp. The tiny rubber/plastic feet keep it from slipping around on my entertainment center, and the speaker connections will accommodate bare wire or banana plugs, but since they're small and closely spaced, banana plugs are much easier for me to use. I also need to use a DAC to connect to my TV which has a coaxial audio output only.The reason I bought this amp was because I had read somewhere that amps with the TPA3116 chips have better sound quality than the Lepai 2020A+ Class-T amps. Having had a Lepai 2020A+ for several years now, and only just recently discovering how much better it sounded than my 20 Year old brand-name 5.1 A/V receiver, I suddenly became overwhelmed with dubiousness and just had to find out for myself what this dual chip version TPA3116 amp with its built in pre-amp was like. Although not exactly a quantum leap over the Lepai 2020A+, there was definitely some improvement, albeit subtle at times, in clarity and overall sound quality. Then again, for testing I only used iTunes 10 with 320 kpbs mp3 files in my Win 7 HTPC connected to an LED TV via HDMI, so it might possibly shine even brighter with better quality audio files.This amp doesn't come with a power supply, so I ended up using a 12V 2A unit I excavated from my decades old "box O' power converters" collection, and it works just fine. I also tried several other 12V units, from 500 mA, up to 3A, and they all seemed to work well too. As did a 24V 750mA, and a 19V 4.75A unit. Whichever converter I used, regardless of the ampere rating, I could only perceive moderate increases/decreases in the power output of the amp itself. It had plenty of power to drive all the speaker sets I tested it on. Like my Klipsch 6", MTM set, JBL, 6" 2-way set, and even my fairly inefficient (about 86 db) 8" 3-way DIY project set. Actually, I usually set the volume knob near the 10 o'clock position and then have to adjust it down quite a bit in Windoz. So far it's been a great little amp for the cost. Now I hear tell that the TDA7498 chip sounds even better than TPA3116! Yeah well, I'm dubious.There are only two things I dislike about this diminutive powerhouse; like most of my modern home-electronic devices it has a bright, annoying led power light; the volume knob doesn't have any markings on it. My simple workarounds were a small piece of electrical tape over the light and a small piece of white tape on the knob—see pic.