Active Subwoofer Jbl

Review by Jon Norris : great little amp - UPDATE - August 2011

This is a sweet little stereo amp based on T-amp chip technology. It is clean and powerful for its size. It comes with a wall wart power supply, but could also be battery powered if one desired. There are input connections in stereo RCA jacks and a 1/8 inch (3.5mm) stereo plug for mp3 players, CD players, video players, etc.There is an actual power switch instead of a pot-based switch as on similar models previously offered by Sonic. There are also Bass and Treble controls, which can be quite handy in tailoring the sound a bit to the speakers and space.I am using these for small PA applications and for desktop computer sound. I have plans to create a small guitar amp setup as well. I have used 6 of these in my "day job" and was so impressed I started buying them for home.I have driven spot monitors like Carvin PM5-Bs and even JBL 10 inch 3-way studio monitors with these and similar amps, and they work very well, especially for small areas. One of these and a pair of Carvin monitors make for some pretty great desktop computer sound. (Until your cubicle neighbors complain, anyway.)I haven't done any actual power measurements, but they are claimed to put out 20-25 watts per channel into 4 ohms, and my ears agree that those figures are probably accurate. I have only run them at 8 ohms, and have been pleased with the sound. I currently use one of these and JBL 10 inch 3-way studio monitors to provide computer sound for a 42 person classroom, and the sound is pretty amazing for a $20 dollar amp.If you are looking for a small power amp that is light weight, takes up very little space, and sounds really good, look no further. Give these a try, I think you'll be impressed, too.Oh, Parts Express is also great to do business with.UPDATE: August 2011In the interest of clarifying the power output capability of this amp (which has caused some contention - see comments), I am re-producing the stats for the TA2020-20 chip from Lepai's own spec sheet, which is freely available on the web."The TA2020-020 is a 20W (4ohm) continuous average per channel Class-T Digital Audio Power Amplifier ICusing Tripath's proprietary Digital Power Processing (DPPTM) technology. Class-T amplifiers offer both theaudio fidelity of Class-AB and the power efficiency of Class-D amplifiers.""Class-T architectureSingle Supply Operation"Audiophile" Quality Sound0.03% THD+N @ 10W 4ohm0.1% THD+N @12W 4ohm0.18% IHF-IM @ 1W 4ohmHigh Power25W @ 4ohm, 10% THD+N, VDD=14.6V22W @ 4ohm, 10% THD+N, VDD=13.5V13W @ 8ohm, 10% THD+N, VDD=13.5VHigh Efficiency88% @ 12W 8ohm81% @ 20W 4ohmDynamic Range = 99dBMute and Sleep inputsTurn-on & turn-off pop suppressionOver-current protectionOver-temperature protectionBridged outputs32-pin SSIP package""APPLICATIONSDVD PlayersMini/Micro Component SystemsComputer / PC MultimediaCable Set-Top ProductsTelevisionsBattery Powered Systems"The diagram with power to distortion curves is even more instructive, and I will try and add a jpeg of that so people can judge for themselves if Lepai is lying about the specs.Are they fudging a bit calling this a 20 watt per channel amp? You could certainly make that case, given that they are quoting those specs at 4 ohms and 10 percent distortion, which is more distortion than most people would find acceptable in an audiophile application. Is Lepai pushing it a bit? Yes, but no more so than most consumer amp companies, or virtually ALL computer speaker makers, none of whom quote accurate specs for their systems.I have been told by tech support for a well-known, widely sold PA amp manufacturer that they considerably over-spec their amps - their 120 watt amp can only be driven to 80 watts; if you go beyond that they WILL fail (which ours had done). Yet, they still sell the amp as a 120 watt amp and no one sues them. Lepai is not fudging anywhere near that badly, and they publish the actual specs for all to see. Carvin is the only company I have found to be truly honest about amp specs (although there may be others). Lepai at least gives one the specs so one can see how much they are fudging.Are there applications where 10 percent distortion IS acceptable? Certainly. Some small PA and background ambient systems would be fine with that level. Obviously, listening to pristine recordings of orchestral music would NOT. A great deal depends on program material, speaker quality, and application. For most applications, 10 percent is not acceptable.Again, I run these amps at 8 ohms through efficient speakers (Carvin PM-5B and JBL studio monitors), and find them to be very good performers FOR THE PRICE. I would not recommend running them into 4 ohms, unless you intend to keep the power level down.At 8 ohms, per their device curves, you can hit 10 watts per channel and stay near or under 1 percent distortion - which is the definition of "High Fidelity" by international standards, and beyond which the normal human ear cannot discern any further lowering of distortion, according to some. At 4 ohms, you can get close to 18 watts per channel and still remain under 1 percent. Is it fudging to call an amp that produces 18 watts per channel at 1 percent distortion a "20 watt amp?" Not by much, and certainly not by the usual standards of most manufacturers. NOTE that with the stock power supply, 12 volts at 2 amps, you could not possibly get more than 12 watts per channel, if it were a perfect world (which it is not). A beefier supply would be required to get closer to those rated specs for the chip in this amp. Personally, I would call this a 10 watt amp, not 20. More and more vendors are adding the channel outputs together, rather than giving the per channel output, which has been standard practice in the stereo world.Even so, I find these to be very useful little amps, and will continue to buy and use them as long as they are available. If you cannot afford the rather modest price to find out, then don't risk your money. If you want a good performing amp for the price of a few lattes, then go for it. I think you will be happy with these. If you are looking for an amp for your Home Entertainment system, I think you will want something with a lot more power. These are small amps for small jobs.Also, if you have a power supply failure, which I did have with one of these amps, Parts Express has very good replacements for a very good price. Parts Express is a very good vendor, and I have bought from them for many years. I bought all 7 of the amps I have used from Parts Express.Still highly recommended.

Review by M. Steven : Ok If Used At Very Low Power

If its power switch worked consistently, it would be an OK amp for low power use.I tried this amp with a pair of Sony SS-B3000 Bookshelf Speakers, and while the sound fidelity was quite good at low (say, 25%) volumes, as soon as it was turned up above 50%, the distortion became obvious and annoying.If you can deliver a good strong pre-amplified signal to it, and not require it to amplify more than a few db, it will sound alright. But don't expect much, it's a cheap piece of equipment.The power switch or power relay on mine began failing after a week or so of daily use. If you're going to use this in a car or always-on situation, perhaps that won't matter as much. Reliability at this price point is not likely to be high anyhow.You get what you pay for.

Review by S. Mayo : Nearly a 5 star amp

It's exactly what the internet buzz says it is: for the price, this is a great little amp. But I save 5 stars for absolutely perfect, life-changing hardware, like titanium sporks. This amp gets a 4.5. If it wasn't so cheap, it would be 3 stars. Build quality is what you'd expect - thin casings, overly shiny faceplate, inadequate shielding, blue LED lighting that is much TOO bright. It's everything you think of when you think "made in China." The controls work well enough. The spring loaded wire clips are the standard junk you find on any low end device; monster cable need not apply. It looks ok, and it is very small, which is a benefit if you just want to tuck it into a corner and forget about it. The RCA jack inputs are a nice step up from the old Sonic T amps. I like the bypass on the tone controls. You'll want to be gentle with it, though. It will not stand up to abuse. It doesn't seem to get very warm, which is a plus. The amp almost certainly doesn't hit the rated wattage - because the power supply is too small. This is ok, because if you tried to crank the amp to full, you'd get distortion and clipping anyway. You may get a slight improvement with a beefier power supply, but in my opinion it's not worth the trouble. The amp's output is adequate for a large living room; you probably don't need more oomph than it can provide. If you do, you're resigned to paying over $22 anyway. About 1:30 on the volume control is probably as high as you'll want to go with this unit. In a more expensive unit, the fact that the amp falls apart sonically when cranked would be an instant ticket to a low rating. At this price range, it's forgivable. Mine is driving a pair of VMPS 626 speakers, which for the size are about as revealing an accurate speaker as you're likely to find anywhere. The source is a classic squeezebox with a decent DAC in it. It's the kind of setup that will do a good job of revealing problems in gear, so I have a very good idea of what this amp can manage. Bottom line, it's a typical T amp. It does a much better job than it should, for the size and price. The sound is slightly warm in the mid-range, without "tube" sound. There's not enough power here to manage strong, precise bass, but with a dedicated subwoofer and sub amp in the chain, that won't matter. It's a little thin up top, which surprised me. Imaging is good. Audiophiles use terms like "fast" and "sparkle" and "slam", which are really hard to define, but you know them when you hear them. This amp has some slam, no sparkle and is not at all fast, but it still manages to convey a general sense of clarity. I suppose the audiophile adjective I'd use is "smooth". I can't comment on the depth of soundstage, because it's not in the kind of room where I can really assess that, but I think it has some, which at $22 is unexpected. In short, it sounds very good, without any pretense to a "you are there, live" sound. I don't know how to do better with $22. If you want decent sound on a tight budget, this amp and the best speakers you can manage, are a great choice. For an audiophile, this is the system you put in your bedroom for background music - good enough not to bother you, not good enough to tempt you down the path of endless adjustments. Kudos to Amazon/PartsExpress for getting it here a day early, and packaged so that it would survive shipping. Addendum: I got a second, and use it in my bedroom. The blue LED is so bright that it functions as a nightlight. That is acceptable to me, but your mileage may vary.

Review by Mojave Bob : Throw away the AC adapter!

For the first couple of weeks, I hated this amp. Connected to my Denon speakers, it has terrific sound, and seems well built, but it had this nasty buzzing sound that drove me up the wall whenever the amp was on but nothing was playing loud enough to drown out the buzz. If you read the reviews on this amp, many, many people complain that there is no power adapter included. Then, you will find some comments that they are including a Vonage power adapter with it now. You will also find some complaints about an annoying buzzing sound. Well, my friends, the buzzing noise comes from that Vonage power adapter. If you provide your own 12v power supply, it works great and has very clean sound. I thought about returning this unit, but I can't get anything comparable for even twice the price, and 12v adapters just aren't very expensive. In my case, I had one just sitting around, and was delighted with the result. The amp is a keeper, the Vonage power supply is a tosser.

Review by Reviewer : This little (literally: little) amp works very well

I tested it with 4 Ohm ADS L-300 speakers in cast aluminum enclosures, and with newly refoamed 8 Ohm Boston A40. It sounded sweet with both sets of speakers. It pumps sufficient watts to fill any room with really pleasant sounds and is stays completely cool to the touch. The Tripath chip used in these little amplifiers has high efficiency - around 90%, that means only 10% of the supplied power will warm it up. So, for 10 Watts of music, only 1 Watt goes up in heat. Most popular audio amps have about 50% efficiency, so for each 10 Watts of audio power you would get 10 Watts wasted in heat.There are a few variations of the TA2020 amp available on the bay:1. Different colors: silver, black, golden tan2. With a single volume knob3. With three knobs (volume, highs, lows)4. Different sets of input/output connectors5. With or without output relays to eliminate the thump in speakers when turned ON or OFFThe thump comes from a momentary presence of DC voltage on the speaker terminals. I used Fluke 117 to measure its momentary peak value: it was 0.48 Volts max. This causes the unpleasent ON/OFF thump. If you can't stand it, then get a little more expensive version with relays.The only thing I would improve is adding a version of the amp with remote control for the power switch and volume control.

Review by Sunglass Evaluator : Great Value but Not Perferct

For the price this level of quality would get 5 stars, but there are a few aspects that might make me pay twice as much to get another brand. The negatives are that there is significant signal glitch back into the input lines and significant pop of the speakers when turning the unit on and off. I have the inputs paralled into a powered subwoofer, and the subwoofer makes a very loud boom when I turn this unit off, which means it generates a glitch back into the input lines, which is really bad (there's no excuse for that). This could damage whatever is the source unit. By connecting everything in the system to a power strip, so everything goes off at once, it's not so bad, but I suggest never using the unit's on-off switch to turn the unit off while other connected devices are powered. Another minor complaint is that the tone controls don't have as much affect as I'd like. I conclude they are 1st-order rather than 2nd order controls, but at least it has tone controls, which is better than anything else that price. One other reason to maybe buy a more expensive unit would be this unit has no headphone output. On the good side, it looks super, the output is very clean (distortion free), and has all the desired controls and connections, except a headphone out. All things considered, I'd still buy more of these for certain uses, but I'll pay more for something that doesn't have the negatives I've listed for other uses.

Review by Dave M : Astonishing

Currently running Pandora via Netflix, through this box, into old Dalhquist speakers. Sound is simply astonishing. No distortion, strong warm base, a little muddled in the middle (but hey, it cost less than $20 on Amazon), runs cool, very loud at 1/4 volume. I'm a techie, having build many amps over the past 30 years, including tube amps (Dynaco 70). - There are plenty of amps that cost 10x this, which don't come close in terms of sound quality. This is my first review.

Review by Victor J Leonardo : A few tips that may help.

There is not much more I can add to all the other reviews already written. I am very happy with this amplifier. Here are a few things you may wish to consider with this amp. Your listening experience may be improved with the following: 1. Match this amplifier with a very efficient set of speakers, and you will have no worries about whether the amp is powerful enough. (Dayton B652's sound great their sensitivity is 87db and they are 8 ohms) 2. You do have to consider the audio source that you provide for the amp. There is a lot of compression used in digital music and some of the limitations may become much more apparent as this is a pretty clean amplifier. If your soundcard or mp3 player is pushing its output to the max it will be distorted. You have to listen and find the best balance of volume settings on the source, and the volume settings on the amp. 3 If you are really interested in improving the power output to move a little closer to the touted specs, you should consider a REGULATED 12V 4amp power supply. It will provide you with consistent 12v power and the amperage will allow the amp to draw to its limits. Unfortunately, most power supplies that fit the bill will double the cost of your total investment. But it may be worth it if you feel you need a little more punch and a little cleaner sound. I am very happy with my amp and my Dayton speakers. It has made me realize what poor sound I have been listening to with my 2.1 computer speakers until this upgrade. Not a bad deal for a total of about $70 (speakers included). I am now buying the same setup to power the sound for my LCD TV.

Review by M. M. Jackson : Beats the previous TA2024 designs with Fostex high-efficiency drivers

Super excited to be here reviewing this miniature marvel. As you can see, I've drunk the Kool-Aid but I've been a T-amp fan for years. Cheap, delicious, imperfect, but miraculously close. It's like someone giving you $1400 worth of valuable stuff for $25. So, as the whiners and snobs point out, maybe it doesn't beat the $2500 stuff...but it sure beats the $1200 stuff! For the price or the next five price ranges, you just can't beat it.I have had a T-Amp for three years now, using with my Fostex FE206e - based speaker system (using David Dicks' "1.3" speaker design) which I have loved. Imperfect but good enough for me and a H*LL of a deal in DIY.At the time, the T-Amp costed around $55 and was worth every penny, but now I saw that there was this TA2020 amp was only $25 and I had a pair of space-age-y vintage speakers to use out in my gameroom-garage, therefore this thing plus my iPod fit the bill for a cheap way to get high quality music out in the gameroom. Even if it was crappier than the TA2024-based original Sonic Impact 5066 model T-Amp, I knew it would be close and good enough.Well...I get it home and having a Pyramid 13.8v 3amp power supply (available on Amazon now for only sixteen bucks!) already, I plugged THIS amp into my media room setup, in place of the TA2024-based Sonic Impact T-Amp.(Note to audiophiles: I had removed the amplifier guts of the T-amp, removing the volume pot and wiring it INSIDE of my Dantimax remote control 5-input preamp...it was small enough to easily fit inside. I just installed two power jacks and was using two separate plugs to power the amp and then the Dantimax).Anyways...WOW! Bass EXPLODED with power and control. Took me aback! Kept all it's life and clarity, but the bass was not flabby, not wild, just pure and powerful. Distinctly more natural sounding, more real and alive. The authority of it was head and shoulders above the TA2024 Sonic Impact 5066 amp. It instantly became clear to me that the Dantimax was going to be RE-AMPED in order to use the superior (in my system) TA2020A+ amp guts. So that is where I am headed, and I just put in my order for my second TA-2020A+ today.Very excited to get it and PLAY.p.s. make sure you get the 2011 TA2020A+ version...the ability to defeat tone control is CRUCIAL! Setting it to "0 / 0" is SIMILAR but not the same...it is altered sound for sure.p.p.s. remember, garbage in, garbage out...my harsh CD's still sound harsh with hot treble...but well-recorded discs just sound amazing with a whole new life in the low-end. The previous setup was a bit peaky in the lower bass as well as bass-shy. VERY pleased with this development in chip technology and sound.My recommendation is a solid "BUY.".

Review by Nailong Guo : Miracle!

The outside quality is adequate. The sound is full and balanced with a wide range. I didn't expect that the lows could be so strong and deep from such a tiny closed aluminum box (still cool with running for a long time, say one hour from my impression) costing only about $25 with shipping and handling charges. It's a miracle! When the volume is up to 2/3, there is still no discernable distortion. The 3.5mm input jack is extremely convenient for you to connect almost every audio source. The only weakness to date is that there is a noise (not big though) when I shut down the power, even if I turn down the volume to zero. In a word, this product is almost perfect for its purpose, especially when you take its size and price into account. If you need a simple and compact stereo, buy it ASAP, since the price could go up soon, and since you'll be most likely impressed..