HiFi Bluetooth 5.0 Tube Power Amplifier Coax/Opt Integrated Audio Amp USB Player

Ok so I’m running a Pro-Ject turntable through a Fosi Audio preamp. I have Klipsch R-51M bookshelf speakers on homemade stands and a Sony powered sub that came with an A/V setup many years ago.Unboxing, I was impressed with just how heavy this unit is and how heavy the cardboard boxes were. Very securely packaged.I chose this over the Dayton Audio HTA200 simply because I already have a preamp I like. The Dayton comes with phono in but I don’t need this.First impressions after setup. Setup was straight forward enough that anyone moderately experienced with stereo components won’t need the instructions. It’s a nice manual though.I started with a Phil Collins record for a couple songs. I leave the bass and treble set at the detent at 12 o’clock. Sounded great so I tried Rush Hemispheres for a full side. Really just sat there enjoying the music and sound which was so much improved across the board from the old A/V receiver I had been using. I’ve heard these need a break-in period to sound their best but mine crushes my old receiver out of the box.Then I tried my 45 rpm Dave Brubeck Time Out from Acoustic Sounds. Partway through I went over to the subwoofer to tweak the level and realized *I hadn’t plugged it into the power strip*. The subwoofer was off all this time and I didn’t miss it at all! That’s how much bass this amp was getting out of my Klipsch bookshelf speakers, and these are not speakers noted for having much bass. Amazing.I also listened to music streamed from Napster to the included Bluetooth, sounded great and my tape deck did great as well.I don’t have enough experience to say how this would compare to this amp or that amp but I like almost everything about it. I do agree with other reviews saying the remote volume is a little touchy. Doesn’t bother me, just glad to have a working remote! Also the ability to use headphones would have been nice but I guess it’s an excuse to pick up a Nobsound or Douk headphone amp :)Great job Nobsound!

As Alain Bouchard mentioned in his review, the sound on the amp cuts out when the volume is low. The audio itself is great and the subwoofer out is really a great feature, but also like Alain, the response from the manufacturer wasn't good and eventually I had to request a refund from Amazon directly.UPDATE 2/20/23: Just before I sent the amp back in for a refund, Douk replied with a potential fix that I'm giving a try. It's a USB FW update that addresses my issue. From Douk:"Since amplifiers will produce noise when there is no signal input, we design a signal detection function. That will silent the amp when there is no signal.But maybe the threshold is not that specific, when you only want to lower the volume, the amp will also silent itself.The original design is just to control the idle noise.We can send you a software to upgrade it and lower the threshold. Then it won't silent itself. But the noise may be slightly higher."Adjusting my review and will post back as I really do think the sound quality of this amp is superior to the others I've tried at this price point.

Well so far I absolutely love the Nobsound AV-525. I'm not having any issues with sound dropping out or hum or anything else like that. With no input at all and the volume up it's silent I did buy an upgraded power cord (ASIN: BOB53LQD2R) and have only used that with the Amp. Also using GearIT 12 AWG speaker wire which is connected to Jamo S 803-WL's. Thanks Nobsound for a very cool very quiet amp and Amazon for having all sorts of cool stuff to go with it.I thought I would update my review now that I have added a Jamo 10" Subwoofer. It's even more awesome now! I thought I might add that I have only used it with Bluetooth so far from my Samsung Galaxy 10 plus and it's flawless and I'm playing FLAC files. I love "I Robot" from the Alan Parsons Symphonic Project. This show was recorded live in the Parque de los Pies Descalzos (Barefoot Park) in Medellín, Colombia with the Medellín Philharmonic Orchestra. It's a very nice listen. Oh and it's available here on Amazon.

This is a hard review to write.After waiting almost two weeks for the first AV-525 to come in, I was excited but quickly disappointed. Only one channel worked and it was very crackly and muffled. After talking with Amazon support (which really didn't know much about audio equipment) I was quickly moved to customer service which decided to RMA it. Not only did they agree to that, But they sent me a new unit in two days. In the meantime, I did send a email to Douk audio about the issue, but they only responded 24hours and I was convinced it was a bad unit and dealt with Amazon on getting the new unit.Douk was responsive and I let them know a new unit comping from Amazon, so they simply replied to see how it worked for me.I got the new unit in and all I can say is WOW! Everything worked, and the tube preamp made the sound sooooo much clearer and warm. I was totally blown away. DEFINITELY worth giving this item another chance.I responded to Douk that the new unit worked beautifully and the responded asking what I thought new features should be. I gave them a list including streaming capabilities and the ability to setup a bluetooth subwoofer, among other things.I really feel since I got the response I got from both Amazon and Douk audio, there is more to a purchase than just the item. It was well worth the trouble and I am completely satisified with the end result.This Amp is just amazing. Listening to some "Nothing else Matters by Metallica" as I type this.Kudos to Amazon and Douk audio. Could I have spent over $1k on something better, yes, but for the money this is a pure joy.If you make a few thousand of anything, there are bound to be some bad apples.I hope this helps others when making a decision.