Low-cost hi-fi: the amazing world of cheapo mini-amps

Back in 2005, I wrote about the Sonic Impact T-Amp, a $30 toy amp that stereophiles had figured out how to mod into a brilliant, high-quality amplifier. It was one of my most popular posts, ever, and many of you have written in over the years to tell me about your own T-Amps and the remarkable sound you were getting out of it.

I asked the stereophile friend who recommended the T-Amp in the first place what had become of it, and he told me that there was a new version, called the DTA-1 Class T, that is better built and sells for a still-very-reasonable $45. Judging from the glowing customer reviews, Sonic Impact has continued to produce astounding sound-quality for the cost of a pair of cheap laptop speakers.

But my friend had another suggestion: for a mere $20.67, you can get a LP-2020A+ Lepai Tripath Class-T Hi-Fi Audio Mini Amplifier with Power Supply and a pair of $51.99 Dayton Audio B652 bookshelf speakers, and get some truly high-fidelity sound reproduction from your phone or computer for a price that nearly beggars belief.

This Lepai/Dayton combination comes from CNet's Steve Guttenberg, who reviewed them in May, saying:

Considering the minuscule 1.5-by-5.5-by-4.5-inch amp's rock-bottom price, the Lepai is surprisingly well made, has adequate features, and sounds very decent. And for an inexpensive speaker pair, the Dayton B652 has an unusually large woofer -- it's a 6.5-inch polypropylene cone -- and the speaker also has a ferrofluid-cooled 5/8-inch polycarbonate dome tweeter.

If you think the $199 Jawbone Jambox Bluetooth speaker sounds good, you'll flip over the Dayton/Lepai sound. True, it's very much a wired home- or office-bound system, but it plays louder, sounds dramatically clearer, and actually creates a true stereo image (you can place the two speakers as far apart as you like), something no single-box speaker at any price can ever hope to achieve. Hook up your computer, phone, or portable music player to the Lepai/Dayton combo, and enjoy the music.

Update In the comments, rambles_off_topic sounds an alarm about the speakers: "I believe Steve's review of the Dayton B652s was from May of 2012. Sometime around January of this year, Dayton started sourcing the components of this speaker from another manufacturer (or possibly the same manufacturer, but they are not the same as the components in Steve's review, there's still no clarification from Dayton). In any case, almost everyone agrees that the new version of the B652 sounds terrible compared to the version reviewed back in 2012. I'd encourage folks to research this prior to springing for the Daytons."

Sonic Impact DTA-1 Class T amp

LP-2020A+ Lepai Tripath Class-T Hi-Fi Audio Mini Amplifier with Power Supply

Dayton Audio B652 6-1/2-Inch 2-Way Bookshelf Speaker Pair


  1. I have that Lepai amp and absolutely love it. It was cheap as hell but produces a really nice, clear and loud sound. I have an inexpensive Audio Technica turntable so I’m not looking for super duper hi fi expenses. I just want something to play my LPs on and the A-T turntable with the Lepai amp and the speakers from my old Sony stereo works perfectly for my needs.

    1. Do you know if the Lepai’s control knobs are potentiometers or rotary encoders?

      My current set of (deeply undistinguished, pack-in with some computer I’ve forgotten about) speakers is starting to succumb to potentiometer wear, and it is really, really, annoying. I’m looking for something where my volume-fiddling won’t leave the things with dead spots and nonlinearity.

  2. Oops. Check out the recent negative customer reviews of the Dayton B652 speakers. It looks like Dayton has ruined the design and construction since the review cited above (May 2012).

  3. Cory,

    I believe Steve’s review of the Dayton B652s was from May of 2012.  Sometime around January of this year, Dayton started sourcing the components of this speaker from another manufacturer (or possibly the same manufacturer, but they are not the same as the components in Steve’s review, there’s still no clarification from Dayton).  In any case, almost everyone agrees that the new version of the B652 sounds terrible compared to the version reviewed back in 2012.  I’d encourage folks to research this prior to springing for the Daytons. 

      1. Yes, yes. Inquiring minds want to know.

        I wonder how the Monoprice 6.5″ bookshelf speakers compare.  They’re certainly cheap and some reviewers say they’ve paired them favorably with this Lepai amp.  But other reviewers fault the quality control and the component quality.

      2.  Search for “B652″ on reddit.  The top search result outlines the problems with the new version and there are additional threads that suggest recommended replacements for the B652s.  The Micca MB42s that _SomeDude_ recommends below are one of them.

    1.  This could be due to facorties going bankrupt. It happened last year with a brand. The Chinese factory where they made some of their radios went bankrupt. As a result they had to go look for another one to make their cheap knockoff radios. This could result in poorer quality and materials.

  4. I’ve had my eye on the Lepai for a while now, thinking of doing a custom sound bar project. And just the other day I ran across this clever Lepai-based ammo-can boom box, which is battery powered and could even be outfitted with a bluetooth dongle to make it completely wireless.

    1. Thanks for the post of this one and I’m glad you like it. I do now have some available so If anyone is interested please let me know. 

  5. Those little Class D amplifiers are quite amazing. Especially when you look inside the tiny box and see that it’s mostly air!  The work is all done by one IC that doesn’t need much of a heatsink.

    I have been building a bike stereo for the RAGBRAI crowd in Iowa, using a Texas Instruments Class D amplifier chip, with a piece of 6″ plastic pipe serving as the speaker cabinet. The stereo attaches to the rear rack and provides this sort of sound wherever you go.


    1. Great design! The detail really shows in the clever work you did on the speaker covers. So do 6″ car speakers fit snugly in a 6″ tube, or did you need to do some creative shimming? This strikes me as a good project for some instructable type documentation, if you have the time and inclination… 

      @thread: As far as the Lepai Tripath amp goes, I can confirm that its a pretty good amp. Don’t expect *super* loud volumes from it, it definitely starts distorting around the semi loud range, even when connected directly to a car battery. And by the way if you’re trying to get the loudest volumes from it, make sure to replace the included 12 volt adaptor with something beefier. Or, of course, just use it in a 12v environment where you’re connected to a car battery or similar.

      1. I used 6.5″ Kenwood marine speakers in 6″ ABS pipe. The pipe needs inner support rings installed in each end to provide screw anchor points. There is an instructable called Bike Boom Box.

        I used a 14.8V (really 16V) lithium ion pack made by Batterspace. The extra 4V helps increase the power level.

  6. One Lepai amp. One M/C battery (12v-10Ahr) found in the garage. Two 8″ PA speakers with Piezo horn tweeters on offer from Maplins (I forget, £39.99 ?). One iPod Classic 160 = about 8-12hrs of party time in the woods. The only downside is that there’s not much headroom. Over drive it and it goes suddenly into clipping distortion. The key is the PA speaker sensitivity so instead of 8″, try and find some eBay 12″ or 15″. The next step up is 24v or 36v T-Class amps, look hard enough and you’ll find the bargains for not much more money.

    The current Lepai’s have some protection built in. It was easy with the early ones to kill them with a speaker short or reversed battery.

    1. You can’t overstate enough the importance of using real speaker systems. A pair of decent home stereo speakers will sound amazingly loud and clear with these amplifiers. PA speakers are better for cranking it up, as they are designed for continuous operation at full volume.

      My other bike stereo is The Loud Bike, which uses a couple 12″ PA speaker systems built into Sonotube enclosures, and a Pioneer Class D car trunk amplifier (150W/ch bridged into 80 ohms).


      1.  I would probably forgive you if you played that riding past my house, but only because of the upholstery.

  7. The Daytons and many similar units list their frequency response as 70hz on the low end. That’s simply not adequate for most types of music. The bottom note fundamental on a six string electric guitar is 82hz. The bass guitar and drums are situated well below that.  A cello reaches to 65hz, a piano to 32.

    Personally I think that if you’re actually looking for good music reproduction, you need to have a reasonably flat response down to 40hz, whether it’s via wider full range units or a subwoofer.

    1.  If you want bass, you need volume. See my post on the Loud Bike above. It is pretty flat down to 50 Hz, but takes up a LOT of space.

  8. That Lepai amp looks like a good deal at basically $20, but everybody seems to agree that the included power brick (if it is included, some people apparently didn’t get one?) is total crap.  One of the Amazon pictures even shows where the guy pulled off the Lepai sticker and found the original manufacturer’s markings indicating that it was a 1.5A supply, not a 2A supply like the Lepai sticker said. 

    Of course if this is for car use then it is no problem, just run the thing off of a Cig lighter or directly from the battery and you’ll be golden.  If you’re running it off of house power, then you’ll need to source a different power supply. 

    Unfortunately I can’t find the plug size or polarity listed anywhere, so you’ll need to either do some more googling, or buy one, pull out the calipers/multimeter, and then buy the power supply separately. 

    1. Little crap plugpacks are usually 12v, center positive, with diameter the major variable(sometimes the quality is even shoddy enough that interior diameter can bite you, that’s always annoying).

      1. That’s not shoddy quality, that’s lack of a single standard.
        The two predominant standards are 5.5/2.1mm and 5.5/2.5mm OD/ID. I have no idea why there are two, other than some one in the seventies wanted to play a prank on us.

    2. Looking at the amazon “frequently bought together” items shows a bunch of 12V 5A power supplies for LCD monitors and the like.  I’d be willing to bet they’re the right plug size.  (Well, I’d be willing to bet the $10 or so a power supply costs)

  9. Like the conversation above, but the big thing I ran into was the last though in the original article: this is a WIRED solution. My quick solve? a $25 DAC (digital audio converter) which can take the optical audio output from my apple TV and turn it into stereo R/L or 3.5 minijack out to my Dayton T-amp and, yes, those same Dayton bookshelf speakers. Oh, and a two dollar monoprice cord. With a 40 dollar ikea bedstide table and a powerstrip, i have all of my apple TV media, as well as audio out from my computer, iphone (my girlfriend’s iphone, my friends iphone, etc.) coming out of a BOOMING, rich, compact sound system. The apple TV is a pre-req, obviously, but everything else was sub $100, especially if you dig around for deals. The DAC was the hardest to find (just to make sure you have optical to minijack. if you have the Lepai, with stereo in, it’s easier) but everything else was on amazon for cheap.

    1. It doesn’t interact with your network; but if you just want wireless from device to speaker, bluetooth A2DP receiver modules are ~$10, sometimes less with a following wind.

  10. I tried the lepai tri path amp pictured from parts express and got one that seemed to have been opened before and had an atrocious noise floor and horrible build quality, much worse than the $40 pyle amp I replaced it with. 

  11. I got the lepai amp paired with some speakers from craigslist. So for less than $50 I have a system that outdoes anything you can buy new for the same price

  12. I love my Lepai.  As long as your expectations aren’t unrealistic about what it can do, you’ll be extremely pleased for the price.  I have mine hooked up to a pair of Pioneer FS-51s I got off Craigslist for $80.  The setup is a bit ridiculous for computer speakers (the Pioneers are floorstanding speakers), but I can’t imagine better sound for $100.

    For the person noting the 5 amp power supply on Amazon, you are correct that the power supply works with the amp.

  13. Like someone mentioned above:
    They sell all kinds of parts to DIY your own, including Dayton speakers (and several other brands.)  They also list the specs for them so you can work out dimensions and frequency response curves if you are so inclined.

    -I’m not affiliated with Parts Express, just a customer who likes what they sell at the price they sell it at.  Besides if you are looking for “brand name” gear I go to Sonic Electronix

  14. Just have to add that I used a T-amp to get a nice powerful bike sound system.  I found some fairly high efficiency outdoor speakers, and I can seriously crank the sound for about 3 hours on 10 AA 2675 mAh rechargables I found.  Most of the bike folks I know are still using lead acid batteries, so I wager with a T-amp and a good set of outdoor speakers with > 90 db efficiency, you can get one of the best weight-to-volume-to-battery-life systems out there.  I can fit mine on my back rack with a simple trunk bag, and it can outdo many a trailer system.

  15. That looks pretty nifty — does anyone have a similar suggestion for a cheap-but-good 5.1-capable system?

  16. I ended up with a Topping TP21 amp. A bit more expensive than the ones shown, but still VERY reasonable. Also a much better build quality, and it incls a headphone jack. Got it connected to a pair of old Realistic Minimus 7 speakers I bought off of eBay that were in almost new condition. Very nice setup.

  17. Does anybody know if i can use two inputs simultaneously with this? I want to drive my Mac and my Sonos through something like this and want the sound mixed. Basically i want to listen to Sonos, but when some notifications come in or i listen to a video i want the mac output to be available also without having to switch something. Any suggestions for this? (Besides routing the Sonos through the Mac which i do currently). 

    1.  All you need is a passive mixer. They are reasonably cheap, but way cheaper to build yourself.

  18. I’m looking for suggestions on loud (108 Db +) options that are wearable. These would be for Mardi Gras parades, so they need to be able to be worn while walking up to 15 miles. So far my only option has been megaphones.

  19.  What I’m wondering about: Is the DAC in your phone or MP3-player really good enough for proper Hi-Fi? I’d guess that mine isn’t, and especially the laptop’s is definitely not.
    That said: Isn’t there a comparable amp out there somewhere that also has a digital S/PDIF input or even bluetooth? That would be sooo cool, because all I can find these days is a few numbers bigger than I need it.

  20. Had one, lasted 6 months.  Sound was good until cranked.  Later switched to Pyle FFA 200 and hooked two Pioneer car speakers, housed inside a 1952 motorola radio replacing my computer speakers.

  21. Aww dang it, I wish I knew about this before. Well I knew about that amp but I already got one (well two actually), but I recently ordered a AudioSource S325 80W soundbar from Woot because I was having a hard time finding speakers locally and I really don’t know what to look for in audio stuff. I’m hoping it’s atleast decent, but if I do upgrade I’ll probably pass it on to a family member.

    /edit: actually both pre-amps have rca-jack outputs, so that’s why I was having a hard time finding speakers.

  22. I have ordered this amp. Next step: speakers. I can’t find any EU webshop selling the Micca MB42 suggested by several above. Any recommendations for ~50$ (or ~50€) speakers that are available over on this side?

  23. incredible little speakers from days far gone by… I used to sell ’em for Tandy in the UK and when the company was sold to carphone warehouse all of the non phone items were on sale at enormous reductions to staff.  I bought 2 pairs and ran them alongside a JBL sub and a Marshall 2×12 on my first hi-fi system.  Then I got a bit excited one night and Slayer killed them. :0(

  24. I have a similar micro no-name Tripath amp  £25 and a pair of Q Acoustics 2010 speakers (about £150), and it’s plugged into the TV headphone socket. It sounds flippin’ amazing. I don’t miss my Denon/Mission 5.1 system at all. 

  25. Has anyone with the Lepai installed this in a car? Can the face plate be flipped over, so the mounting brackets are on the TOP of the box (for under-dash mounting) do you think? Just got mine and I gotta say… wow. Can’t believe the quality of the sound for only $20 USD and change…

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