Nobsound NS-03G SUB

It works alright, always planned to connect my passive sub into my receiver, and when I got this, this little thing soles my subwoofer issue

For its size it works fantastic. I have an old Polk audio subwoofer that the main board inside stopped working. I bought this to bypass that board so I can continue using the sub. The sub is a 4ohm 12" sub in the polk audio box. The amp has no problem driving it. (The included instructions say to use it with 8" or smaller) I have the amp connected to the subwoofer output on my receiver, I did have to get creative with the adaptors. The receiver output is a mono channel RCA (LFE) and the input to this amp has to be a stereo 1/8". I had some extra adaptors laying around so that wasn't an issue. Once connected, powered up and volume adjusted it works great. Doesn't get hot and no static. Hopefully it'll last longer than the Polk audio board did. 5 Star for me. If I come across another broken sub I will buy one of these again.

I purchased this amp and the power supply recommended in the description to replace the PA amp that I had been using to power my home theater sub woofer. Considering the price and size of this amp, I had very low expectations. Upon connecting this little gem, I was amazed. This tiny little box delivers more than enough power to drive the sub. The volume control is smooth, with no noticeable pops, cracks or distortion which is common in an amp in this price range. The sound quality is better than I was expecting as well.Is this tiny little box comparable to an audiophile amp like the Marantz Mono-block amplifier? No, but the cost is also significantly less. For the price, this is an incredible value. It does exactly what it should and doesn't break the bank doing it. I can confidently recommend this amp to anyone looking for a decent product at a good price.

EDIT 17 Aug 2025Long story short, the new version is a terrible subwoofer amplifier.Note 1: Connect the power supply to the amplifier before plugging it into the wall or power strip. The new version can cause sparks if you reverse that order.Note 2: This amplifier requires a power supply with a 5.5x2.5mm plug. A 5.5x2.1mm plug will not fit.I LOVE my first little Nobsound subwoofer amplifier, but the MFG has changed the design radically since my first purchase in 2022. I cannot give this product more than 1-star as a subwoofer amplifier. There are now fewer capacitors, so this no longer has the power to drive even a modest subwoofer. This is now identical to the full-range amplifier, but with a jumper that sends audio through an RC low-pass filter.The MFG reduced costs not only by reducing the number of capacitors, but also by using electrolytic capacitors rated at 25V instead of polymer capacitors rated for 35V. I do NOT recommend running this higher than 20V. Similarly, the MFG removed the DIP switches (for adjusting the gain) to reduce cost.As a full-frequency amplifier, the power seems similar to a stereo TPA-3118 amplifier I own, though the Nobsound does appear to be using a TPA-3116. While my stereo TPA-3118 amp produces about the same volume on two channels, the Nobsound generates no noticeable hiss. I never noticed any hiss on the older Nobsound amplifier, either, so I am not sure why the new Nobsound has such low power output.I estimate I am getting about 10W out of an 8ohm load with the new Nobsound amplifier. My older Nobsound is probably pushing close to 30W into the same load.Do NOT waste money on the subwoofer version. If you want a clean-sounding mono amplifier to drive a small surround/center channel, go buy the full-range version and a 19V power supply. The cheaper components, fewer capacitors, and seemingly reduced gain make this a terrible subwoofer amp.EDIT 29 July 2025I love my first subwoofer amp so much, I decided to buy a second one. My first amp has a Blue power light, the new one I received has a Red light. The Blue sounds great powering my 8", 8-ohm HTIAB sub under my desk. I swapped the Blue for the Red to test the new amplifier, and I had to crank the Red volume to max to get what Blue puts out at ~30%. Same cables and power supply, so I know the issue is the Red amp. To further test the new amp, I powered my computer chair bass shakers with the Red amplifier on a 24V 200W Meanwell power supply. Boosting the signal by 21dB through a DSP, I managed to get a reasonable amount of shaking with the volume cranked to 90%, but it shouldn't take this kind of signal boost. Either this amplifier is damaged, or something else is wonky.Returning to Amazon for a replacement amp. Will update review once I receive the new amplifier.ORIGINAL 5-STAR REVIEW 12 Nov 2024Class-D amplifier uses very little power when not used, so it does not need an auto-off switch. Volume knob doubles as power switch, so you can turn it off manually without unplugging it. A benefit of this type of power switch is that it mitigates any power-on/off popping.Works perfectly with an old 8-ohm 8" passive HTIAB subwoofer rated for 100W. I haven't noticed any noise or hissing with this amp, unlike a different (much higher priced) Class-D sub amp I own. I don't think the Nobsound gets to 100W, but the speaker is plenty loud for a medium room. Connected to a passive sub, this Nobsound amp won't shake the seats in your home cinema... but it would if used as a bass shaker amp.This amp pairs nicely with a 65W/19v laptop power supply and a 50W BST-1 bass shaker. I love how my lounge chair rumbles while watching The Dark Knight, especially when the Batmobile is on screen. I've also hooked it up to four 16ohm 25 watt bass shakers and an old 135W laptop power supply to make my computer chair shake with movies and games alike. I have picked up spare ~19V laptop power supplies free from office buildings being renovated, so I have a few options.This amp has a decent low pass filter, especially for the price, but it will pass the lowest voice frequencies to bass shakers if fed a full signal. I recommend a 70Hz low pass filter, or use an LFE port set to 80Hz, if you plan to drive a bass shaker.The only real negative is it only has a 3.5mm minijack input.I did a head-to-head comparison between this amp and a PBTL/Sub amp from a big F-brand on Amazon. That PBTL/Sub amp did NOT work well at filtering voice frequencies, no matter how I turned the knob. I ended up returning that one and keeping this Nobsound amp. The Nobsound doesn't have a ton of features, but it just works.

Been looking around to power my unpowered sub woofer that I picked up for cheap at a thrift store. It breathed new life into the sub, and works great now. It completed our 5.1 surround system. Plenty of power - just make sure you have a power adapter that'll work with it. The power cord that I had on hand is a bit underpowered, but gives us plenty of bass.

The media could not be loaded. I bought one of these and used it to power a bass shaker under my office/gaming chair. It worked well in that capacity for a year, but then stopped working, though the light still came on. EDIT: This turned out to be downstream from the amplifier, and not the amplifier's fault. The amplifier does its job nicely as long as all the wiring is good.However, the unit will generate sparks if the power adapter is plugged to the wall before plugging it into the amplifier! See video. This happens even with the unit turned off. This behavior is apparently by design (there is a blurb in the printed instruction sheet about it), but not what I would have expected. I don't expect there's a huge safety issue with this, but I imagine the issue could be designed away with a different circuit or power jack, so to me that's worth a star.

With active subs disappearing and becoming ridiculously priced, this IS actually a solution. The passive-to-acitve sub this made, actually sounds better and its quite obvious.Now I do feel that each unit should come with a power supply (cheap to order, but be careful not to get one without!), as well as a 3.5 stereo to single rca... but I assume these exclusions are there to keep the price down, and many of us audiophiles have a bunch of scraps laying around.This is what you want. This is for my piecemeal setup for my pc, and now I can thrift a better active sub!Highest recommendation I can give. Get this, instead of hunting for an active sub unless you need an active sub for a setup that should have an active sub already!PS: Currently using it with a 15v 1a, and it is working great. Full range on this older Samsung HitB mini sub.