"This comes with batteries and no power supply. (Info below.) I like the sounds I can get. It’s tiny and tough. I plug in headphones, connect my phone to play along, and sit next to it. I’d say 4-stars because it’s $100. If it were $80, five stars. If a friend was selling one for $50 - absolutely! But it’s only $20 cheaper than my neighbor’s Fender Champ 20 which is louder and has better effects. But I think I may just keep this. It’s a portable plastic lunchbox that I can set anywhere and play guitar. The fender needs a wall plug and 2.5x more space. You can easily make room for this on your desk and toss it in a backpack.

With x8 AAA batteries (1.5V 2500 mAh), this thing (350 mAh) should last around 7 hours - probably longer on headphones.

This "Requires" a $40 Roland PSB-1U power supply. (Pic)

If you want to use a different power supply (the amp says not to), search "Center Negative 9V 2A 5.5mmx2.1mm power supply".

You don’t have to get 2 Amps. The device draws 350mA, so a 1A, 2A, 3A power supply should all work. However, you do need to match the following things exactly: 1) 9V power. 2) The tip size needs to be 5.5mm x 2.1mm. 3) The tip needs to be CENTER NEGATIVE.

If you have a power supply, and want to know if it works, read the back. Check for the 9V, at least 1A, and diagram that looks similar to this:
(+) --- Co --- (-) This means center negative. It should work.

If you see this:
(-) --- Co --- (+) This means center positive. Don't use it. Also: Most power supplies are this.

Lastly, if the barrel plug is 5.5mm it should fit snug not floppily. These are standard sizes and it should be clear if it doesn’t fit. Don’t have it plugged into the wall when you test fit the tip.

UPDATE: Got some batteries."

"This is all a lot of us just need. We don't need the chorus and the flanger for example. Give us a nice delay for an echo effect for a reverb effect and we're good to go. This is good for a hard rocker or metal player. I just stuck batteries into it so I can stick it anywhere I want or take it into the bedroom and play or take it to the living room and play just depends on my mood. Has a nice clean channel too I might add. But I like that it doesn't have software that it relies on to get your tones and sounds it's just straight up what you see is what you get. Nice little seven watt amp sounds great You can rock out or you can play clean. Up to you. I do both depending on what song. Packaged was great but the internal packaging of the unit itself is also very protective. So if you're not going to play for a while you can pop the batteries out put it back in the box stick it in the cupboard and it's out of the way. Anytime you need it you ain't get out pop the batteries in good to go. I haven't played long enough to kill the first set of batteries. I would think that this would be good if you're going to mic your guitar at a gig. Just get your sound coming out of this baby and feed it into your mixture and your set."

"Boss can thank Ola Englund for why I purchased this great sounding little amp.
Ola Englund is a guitar player and works for a guitar manufacturer in Europe.
He has his own YouTube channel with a series called "Will It Chug".

Ola did a nice video on this product, and Ola is the reason why I decided on getting this little amp.
I'm not trying to plug Ola. This is a material fact statement, I bought this product because of Ola.

This little solid state amp sounds great for it's size.
it's so loud, I never cranked it up.

The built in distortion is OK, but it sounds great with my BOSS Metal Zone pedal.
I love the digital delay sound on it.

The amp does have a slight tinny sound to it, but it still chugs. Only it doesn't chug with the beefiness in Ola's video because he has expensive recording microphones recording the sound. However, with the proper settings, and additional distortion pedal support, it's a great little portable practice amp.

It sounds great with my Boss Metal Zone distortion pedal.

It's great that you can put batteries in it. But I don't like using batteries because when they start to go bad, they usually slowly negatively impact your sound without you realizing it.

I bought the extra power supply cable and love it. (Boss PSA-120S Power Adapter)

I make home recordings with a Zoom hand held, open room recording device, with this amp, and the recordings come out great.

If you're looking for a great sounding, inexpensive practice amp to travel with, or practice with at home, I highly recommend this little guy.

I've been using it regularly for the past 6 months and am a satisfied customer.

Thank you BOSS for this fine product, and thank you Ola for helping me decide on this!! Cheers!!"