These are great amplifiers to use with small speakers connected to a TV to enhance sound (if you don't have a HT system). I tested this amp a few years ago and it remains one of my most popular videos. I see they are now discontinued, so may be time to pick up a few more to save. There are some other mini amps out now that intrigue me...especially the TPA3116 chip that provides 2.1 output with (yeah, cough, 50x2 and 100x1). I'd expect about 1/2 of that, but I'm going to pick up one and we'll find out...Great, detailed review, especially like the THD portion. Geek out FTW!
In fact there are three amplifiers. The bass and treble are passive and amplified active by the two JRC4558 monolitic opamps, they don't amplify the bass and treble only, it amplifies the whole signal. I think that's the reason why it is so freaking loud when using maximum settings.
thanks for doing this. I believe the manufacturer is rating power for 2 channels. I agree this amp is fine for desktop use. I am using this amp with two cheap speaker ($5/pair) and it can be very loud!
At high volume (but not into clipping) the LEDs on mine would pulse with transients (bass, kick-drums etc'). I replaced the 2200uF reservoir cap (the one you pointed out that will blow with DC-polarity reversed) with a 5800uF one, as big as would fit in the case - 4700uF would probably have sufficed. Some Lepais apparently have 3300uF caps fitted, the silkscreen clearly outlines one at least that big - but even that might still be marginal IMO. the LED's stopped pulsing, so I assume voltage was stabilised, and the amp will almost certainly be reproducing transients better. ETA >> it's quite likely you would have got a higher output with a bigger cap (clipping not settng as early) - in the region of 8-9w 'clean' into 4ohms. ETA2 >> the 2200uF cap fitted is actually as big as recommended in the TA2020 reference board, but apprently the Lepai doesn't adhere very closely to it and it really does need a bigger cap. As I said, the silk-screen indicated that a 3300uF or bigger was originally intended, but further down the line someone presumably referred back to the Tripath reference board and decided it wasn't needed.
Great Review, I wish there was a review of this quality around when I brought mine last year. I brought mine because I finally accepted using a 600w Pioneer hi-fi amp to drive a small desktop 2.0 setup was probably a little excessive, I replaced all the electrolytic's with better quality ones and in the case of the power input cap one of over twice the capacity of the stock, its a far more sensible setup for me.
hi what power supply do u recommend what amerage my lepy lp 2020a is 13.5v and 3a amperage and when turning up the volume on the amp i hear a big pop and static noise increases.
The advertised 20 watts is supposed to be the total wattage, not the wattage per channel. Your test showed that this amp put out around 9 watts per channel, so it is close to 20 watts advertised total when the load is 4 ohms.
The 20W per channel is marketing B.S. Some manufacturers used to call this "Music Power" on the basis that most uncompressed music is quiet with occasional peaks. The amplifier, power supply, and speakers may well supply short peaks of (highly distorted) output which the addled human brain registers as part of the performance. It is the power of these peaks that the salesmen use like snake oil to charm the customers. Your brute force calculations provide a much more realistic approach to RMS power output, especially as you link your measurements to the cusp of drastic distortion.
Wow, I'm amaze when you short the speaker terminal on Lepai and still working very well. My Marantz PM-450 (80's amplifier) blew on all power transistor and transformer when accidently short speaker terminal. And cost more money to repair it.
+Faisal Kadal 30 years ago, protection circuits were a lot more expensive and difficult to implement without causing issues with the sound quality. Today's integrated amplifier ICs are really easy to protect, since you just have everything in a single chip, and performance isn't as critical.
Most modern digital music releases are highly compressed (see "loudess wars") so quite high in-room SPLs can be achieved with an amp like this. However, play a decent 'vintage' recording/transfer, one with a high 'crest factor' (large dynamic peaks on percussion for eg), IOW a genuine hifi recording, and you will not be able to get the same SPL's without clipping and hence audible distortion. I've noticed this limitation with all the Tripaths I own (Lepai TA2020, Indeed TA2020, SMSL TA2021).
The amplifier can handle 20 watts per channel at 10%THD. The power supply is just undervolted to fully drive the TA2020 in the amplifier. The TA2024 in the 2024A series is meant for 12 volt input. In sort, they supplied an under-powered power supply.
FFcossag No. The TA2020, TA2021B and 2024 all use the same circuit. The packaging is just different so that the 2020 and 2021b can support an additional heatsink and thus support higher input voltages, leading to more output power. Check their datasheets.
By all means. If you had done the same, you would have seen the absolute maximum 16 V supply voltage rating for the TA2020. That means that it'll likely go up in smoke and flames once you exceed that. www.e-ele.net/DataSheet/TA2020.pdf
FFcossag Yeah, that's what I'm saying. The TA2020 is mean to work at ~14.5v thus reaching higher output. The 2024 is meant for 12v input. It's just that the lepy on your video is supplied with a 12v power brick.
Hi. Thanks. Brilliant teardown. Do you know if it is possible to damage this amp by connecting one of the speakers out of phase? Blue light but no sound from the lepy after doing this (by mistake) .. but still cant believe this could have zapped the lepy.
hi how would this be possible to use with headphones what would i need i tried plugging headphones in but when i turn volume up they just play through the speakers.
I really like your review. I wonder if you would comment on the component values of the volume control modification, including the resistor values as the bands are hard for me to read on the screen. Also would like to know the brand of capacitor you replaced. Thanks for your channel. It is a real service.
+Donald Ferguson Sorry for the late reply, I never noticed your comment. The resistors are 5600 ohm, and I -think- I used a 20k linear potentiometer as a replacement of the original. The original capacitor in the unit was something entirely generic and probably brand-less, as were all the capacitors inside of it.
i have lepy lp 2020a with 13.5v and 3a amperage power supply for the amp and a 75w studio monitors music plays when turning the volume up on the amp i hear a big pop cuts out for about a second then does it again and the static sound increases how do i fix could it be the power supply what volt and amperage plug do u recommend so i also dont get distortion. the amp is a lepy lp 2020a and speakers are eris e4.5 presonus
What power difference (if any) would you see if the only waveform you had were a square wave, not a sine wave? That's all I have, something I made up from a 555 timer IC. There are loads of these little amplifiers, people do not realise that many of them simply are NOT stereo. They are also not a Tripath chip, maybe a TDA7498, but a amp running in bridged mode. The output is then even weaker: As little as 2.5W. There are also loads of the little TDA2030 panels about. I wonder how they would perform under the same test conditions? I believe that you can get one for as little as US $1.60, but that is not for a cased product.
I noticed mine cuts out and distorts sometimes at high volume when there is a lot of bass. Other than that I think it sounds really good. It is MUCH better than the LP-838.
Hello! Great test and teardown! Very complete! I have a 2020A+ as well, I think maybe a little newer model PCB than yours, but the thing my vol potentiometer is (just as you mentioned here) having some internal connection trouble, I think, because the sound scratches on the left channel as I turn it and I notice the output voltage on the left is way over what it should be. Anyway, I was wondering what 20k pot you put in and where you found it?! I live in France and can't find a 20k pot anywhere!
Great! Thanks for the response! And so the resistors you put on the back were to turn it into a log pot? I'm having some trouble with electrical noise on mine when I touch the dial or the casing, is there anything you can recommend to get rid of this? Thanks again for all the good info!
I NEED YOUR HELP I AM A BEGINNER I'VE BOUGHT THE 2020A+ AND THE UPGRADES FROM A NEXT UA-cam VIDEO BUT MY PROBLEM IS I CAN NOT OPEN IT. ALL THE SHOPS I WENT TO COULD NOT OPEN IT THE KEY IS VERY SMALL I COULD NOT BUY IT ANYWHERE. HOW DID YOU OPEN YOUR. I SEE YOU GOT CROSS HEAD SCREW IN NOW.CAN YOU GIVE ME YOUR LIST OF MODIFICATION AND PICTURES AND KEY LINK PLEASE THANK YOU AND NICE VIDEO OR EMAIL ME
FFcossag More Questions. A common compliant with this amp is the power supply that is supplied. I recently upgraded my computer power supply with a new one and intend to use the old one to power the Lepai, this is a 12v 16 amp source that was the 12 volt source for the mother board, I was thinking this would be a good stable power source for the amp, do you see any problem using this. Thank's, Less Opinion
I have connected Schiit modi's RCA output to RCA inputs on Lepai. I also connected 3.5mm audio cable to 3.5mm input on Lepai this way i can switch between my laptop and iPhone to play audio. Is this connection fine? Or will it damage any of the components?
It's unlikely that you'll damage anything; the outputs of tiny devices like headphone amplifiers and phones tend to be short-circuit protected. However, you are connecting the output of your telephone to the output of your Schiit, and connecting outputs to outputs is something you should never, ever do unless you know what you're doing. When you play something on one of your devices, it will essentially try to over-power the other one (which is working hard to keep its output at 0!), which might lead to distortion, heat, and reduced battery life.
Thank you. The only thing I'd recommend, is running it off of a 13,5 - 14 V power supply, and not a 12 V one. It's built well-enough not to produce much in the way of audible artifacts (from what I've been able to measure), so I can't recommend doing any internal modifications for the sake of sound quality.
FFcossag english is not my 1st language so I cannot say I understand your vdo completely. however, I'm quite interested in your recommendation on running it off a 13.5 - 14v supply, instead of 12. could you briefly explain why that would be an advantage? thanks in advance :)
, I purchased a 19 volt / 2.1 amp power supply and a 24 volt / 5 amp power supply and I purchased two of the newer model the Lepai 2020ti. which is class d and not the original class T.
Thank you for the video. I was wondering, where on the volume knob would the amp be reaching around 5 - 7 watts? I just want to know the maximum safest volume knob location. I have been keeping my volume below halfway just to be safe, but if it can handle anything past that it would be great. Thank you!
Output power depends on your input signal. There is no "maximum knob position". Just don't play it so loud that it sounds bad (treble gets modulated by the bass).
the power supply i use universal ac adapter 15v 3.5v 90W MAX MADE IN CHINA AND I LIVE IN ENGLAND THE MAX I HAVE PUSH IT TO IS THE ONE O'CLOCK POSITION.I AM WAITING TO MODIFY IT ONCE I GET IT OPEN.I HAVE DONE MY HOME WORK. I HOPE THAT HELPS DO NOT PUSH THEM
The volume pot on the amp is garbage, that's pretty much the only reason I'd buy a higher end model 2020/2024 amp. The volume pot on mine went out and fucked the sound up hard, sprayed it with some lube and it's back to normal, the pot has terrible feel though. Could you explain why 5 clean watts per channel at 1khz isn't actually 5wpc due to the dynamic range of music, I think that would help listeners better understand the capabilities of this amp and all amps in general.
5 W/ch. is 5 W/ch. no matter how you turn it. The crest factor of music remains the same no matter what amplifier you use, and as such, the average power output will always be set percentage of your peak power (of course depending on the music you listen to). As such, it is rather pointless to state any realistic average power figures, in my opinion, since the point is to bring forward a number that is easily quantifiable and comparable across different amplifiers.
FFcossag Thanks for your review!! I must admit that I have very limited knowledge of electrics in general. I found your video while searching for a way to run one of these little thing in mono. Although you talk about it around 7 minutes in, I didn't quite understand... So is it possible to bridge this amp to run a single speaker in mono?
Thanks a lot for your fast reply. I am now looking into a ta2024 amplifier board on ebay, and looking into paralleling the channels instead. No idea how, and if it is possible yet. You are most welcome with any input on the matter :)
testacorsa150 It will not work. You can't get more than about 5 W/8 Ohm or 17 W/4 Ohm out of a "12 V" amplifier that doesn't have a voltage booster (like a large car amplifier). That's why people often use 4/2/1 Ohm speakers in vehicles.
FFcossag Thanks again, you are a great help - I will drop those plans then :) I am building a 5 liter jerry can portable speaker. I have a single pioneer ts-e2090 speaker, and will drive it with 2x6V - 4,5Ah batteries connected in series. For the amp, the best bet for now is this little wonder: www.ebay.co.uk/itm/161377488531?_trksid=p2055119.m1438.l2648&ssPageName=STRK%3AMEBIDX%3AIT Your input is again more than welcome!
Hey so I am getting a lepy and I have a lepai . Can I bridge a subwoofer with 2 amps ? So I want to put the negative in lepy and positive to lepai and I will get a 3.5 splitter can I get more power if I do that ?
FFcossag greeting. I own a pair of speakers at 2 ohms. I also have hand made amplifier germanium 2x10 watts. the instruction writes on LEPAI amplifiers that can work at 2 ohms. HAVE YOU DONE measurements at the low impedance. I am very interested to buy this little miracle.
The Lepai CANNOT drive 2 Ohms. The box lies, the chip it's built around is not designed for 2-Ohm loads, and running those risks destroying your amplifier.
Hi, its a great review and test of this amp! Do continue! I need some help tho, wondering if you can help me out... My lepai lp-2020a+ just stopped working yesterday.. I think it was due to wrong polarity, i connected my 12v 5A battery, to the amp, and found out i put - on + and + on - for a split second, when i was testing whitch way would work. after i found out what was what, the led light got on. But no sound was send out to my speakers and it just didnt play any sound.. It worked before i cut the DC adaptor wire and connected it to the battery. But now it dosent. Only the LED light worked.. Could this be the Capacitor that got broken due to wrong polar? - Steen
I strongly doubt it's only a capacitor; if it were, chances are that it would still work, albeit poorly. It's more likely to be an opamp, or the amplifier chip itself.
FFcossag But how can it become broken just after a second of switched polarity? Could there be other main reasons it does not work? Nothing is burned in there or looks broken. And would it fix the problem if i change the chip? If it is the OP amp, how can i fix that? Thanks
Steen Zou It takes considerably less than a second to break a chip like that. I can't say for certain what has broken, I'm afraid you're going to have to troubleshoot that yourself. If it is an opamp, it's only a matter of desoldering it and swapping it out.
Great vid. Unit faults aside, 100 hours of burn in is a good rule of thumb. And given the low usable output, speakers rated at around 92db/W would be a good match.
Thank you. However, save for finding production faults, and perhaps getting the initial scratch out of the potentiometers, there exists no basis for assuming that such thing as amplifier "burn-in", exists. A poor amplifier when new, will be a poor amplifier at ten, a hundred, or a thousand hours still.
FFcossag True. There is some rational in a few hours of burn in though. Component parameters do change over time. So its possible that an audio device can sound better or worse over time. I'm very much intrigued by these Tripath amps. A few manufacturers seem to have produced astonishing examples.
fatcat2939 Component parameters do change over time, what I react against is any claim about them doing so drastically enough to audibly affect the sound in a manner of a hundred hours; that's simply not true unless the components in question are faulty. In such a case that faulty components are installed, they're furthermore unlikely to impact the performance of a device positively.
FFcossag, Thanks for the video it's quite informative. As to the volume mods could you be more specific as to the parts used as I am a electro twit. Questions are as follows 1. Vol pot. is this a specific size or type, how do I specify when ordering parts other than it's 20k linear. Please include the tone control pots also. 2. I could not quite make out what you said as to the reason for the resistors soldered to the backside of the board in the volume circuit could you give a brief explanation 3. P/S I am from Missouri USA what language is it that you speak. Ha Ha
+Less Opinion This potentiometer is a "China standard". You'd have to look at the mechanical characteristics of it and find one that matches to do it right, but in this case you can just go on Ebay, type in "20k linear stereo potentiometer", and basically all of the ones that look the same as the original will fit. The added resistors are there to change the linear potentiometer to a logarithimic one. This is because linear pots tend to be more reliable than logarithimc ones, but you want a log response for a volume control. You can just use a log pot and omit the resistors if you want to. Your computer power supply will work fine, but it is grounded, so if you connect the amplifier to another grounded appliance (such as a computer), you might get noise and hum due to a ground loop. I do not know what language I speak, except that it isn't yankeenglish. ;) Cheers
hey i just got one of theses and its driving me crazy, when its powered on with no input, the speakers make a low static noise/hiss, and when i connect an input its still there with my music,i read online that it could be bad grounding but i honestly dont know. can you please give me some advice. i have tried replacing all the wires and even the 12vpower brick
+FFcossag if i open it up and send you some clear pictures could you possibly see the problem, hahaa i know its a long a shot but its worth a try i guess.
saad abass I'm not sure it's worth bothering, I'm afraid. Issues like that are rarely if ever visible to the eye. You'd have to go through it with a meter in order to say anything, really.
If you have two of these, is there a way to combine them to one? I would split the audio cable and double the speaker cables, but this is of course without any knowledge of electronics, I would probably end up with smoke and fire :)
Hi I hope you can answer this.. i recently got a lepai 2024a which seems to be the same as the 2020a but I guess I cranked it up too high or something and the sound quit. After that, the blue light would only fade on and off. I tried unplugging and everything... All it would do from then on is the light fades in and out repeatedly and no sound so i sent it back and got a 2020a now. Can you tell me if that problem with the light fading in and out is easily fixable as in a way to reset it or did the amp just fail? Thanks .
FFcossag Certainly the power of any amplifier and distortion varies according to the impedance of the speakers. In this case, with 8-Ohm speakers the power of this mini amp showed 5,152 W. at 1% THD (measured with Velleman HPS50) even though the manufacturer named TRIPATH indicates 8W.
***** My measurements align reasonably well with the stated specifications (I measured 6,67 W in my written review into 8 Ohm at 13,5 V supply, whereas the chip is specced for 7 W). Keep in mind that the clipping power depends on the supply voltage, and will be lower at 12 V.
Tee Bee You can NOT bridge this amplifier, since each channel already is made up of two bridged amplifiers. You can use a mono adapter to make both channels put out the same signal, but they will not put out more power than in stereo mode.
can someone put this into simple terms for me please? how many watts comes out of each channel? is it safe to run 10 watt speakers on this amp (6 ohms) thanks
The input voltage should not be over 14 V, ever. A 12 V nominal battery is probably the highest safe battery voltage you can run, since a battery always is much higher than its nominal voltage when fully charged. There's basically no difference between voltage coming from a wall wart, or coming from a battery, so the unit will work identically.
Whether or not something is workable. generally has little impact on the Chinese design process. There isn't really any other way that a dicky volume control would cause that horrible oscillation issue.
Great video, most speaker manufacturers simply sum the maximum output powers of the different channels, and call this the power output. Maybe this is what they meant? It's still dishonest I believe
+operationTF7 yeah i agree. i replaced mine with warm white ones. looks much more pleasnt. however after obtaining better equipment over the years i eventually hit that leapi with a hammer
+Hamish Spencer Out of all the people that could have gotten a dud, I'm glad I did; it highlighted the potentially devestating issue with the volume pot, so that people know what they're getting into.
Thank you for pointing that out. I just wonder if clipping and power output levels are also faulty on yours. If so, it would be nice to see the 'real' values.
+MasterGravitron The Lepai was the first, and it's just got such a big reputation going for it that it's hard to break. The newer TPA3116 based stuff that's coming out is going to replace the TA2020 soon enough.
i have lepy lp 2020a with 13.5v and 3a amperage power supply for the amp and a 75w studio monitors music plays when turning the volume up on the amp i hear a big pop cuts out for about a second then does it again and the static sound increases how do i fix could it be the power supply what volt and amperage plug do u recommend so i also dont get distortion. the amp is a lepy lp 2020a and speakers are eris e4.5 presonus
"At that point it's not even music, It's just some kind of noise, like a jackhammer." This guy is pretty funny.
Thank you very much for such a high quality review.
Thank you very much for taking the time to do such a thorough review.
Terrific review. Thanks for taking the time to so thoroughly review such an inexpensive unit.
These are great amplifiers to use with small speakers connected to a TV to enhance sound (if you don't have a HT system). I tested this amp a few years ago and it remains one of my most popular videos. I see they are now discontinued, so may be time to pick up a few more to save. There are some other mini amps out now that intrigue me...especially the TPA3116 chip that provides 2.1 output with (yeah, cough, 50x2 and 100x1). I'd expect about 1/2 of that, but I'm going to pick up one and we'll find out...Great, detailed review, especially like the THD portion. Geek out FTW!
In fact there are three amplifiers. The bass and treble are passive and amplified active by the two JRC4558 monolitic opamps, they don't amplify the bass and treble only, it amplifies the whole signal. I think that's the reason why it is so freaking loud when using maximum settings.
Dude I love this kind of review. I bought an smsl sa50 and I cant find any review LIKE this on it. Keep it up!
zeos pantera did a review on the smsl sa50 and its quite good, check out his channel, good stuff
ziggy8757 thanks man
ziggy8757 ok yea I saw that already. I was really wanting an indepth review like this with electrical equipment measuring watts and clips etc
Is that not 9 Watts per channel into 4 ohms then? That would be closer to the advertised specs.
Aaand this is how a product review should be done! Very, very nice.
percussive maintenance .... well worth watching just for that comment, and shorting the output gave me a good chuckle too. cheers.
I found the waveform review part very interesting to physically see what it means to max out the power and for waveforms to clip.
thanks for doing this. I believe the manufacturer is rating power for 2 channels. I agree this amp is fine for desktop use. I am using this amp with two cheap speaker ($5/pair) and it can be very loud!
At high volume (but not into clipping) the LEDs on mine would pulse with transients (bass, kick-drums etc').
I replaced the 2200uF reservoir cap (the one you pointed out that will blow with DC-polarity reversed) with a 5800uF one, as big as would fit in the case - 4700uF would probably have sufficed. Some Lepais apparently have 3300uF caps fitted, the silkscreen clearly outlines one at least that big - but even that might still be marginal IMO.
the LED's stopped pulsing, so I assume voltage was stabilised, and the amp will almost certainly be reproducing transients better.
ETA >> it's quite likely you would have got a higher output with a bigger cap (clipping not settng as early) - in the region of 8-9w 'clean' into 4ohms.
ETA2 >> the 2200uF cap fitted is actually as big as recommended in the TA2020 reference board, but apprently the Lepai doesn't adhere very closely to it and it really does need a bigger cap. As I said, the silk-screen indicated that a 3300uF or bigger was originally intended, but further down the line someone presumably referred back to the Tripath reference board and decided it wasn't needed.
Great Review, I wish there was a review of this quality around when I brought mine last year.
I brought mine because I finally accepted using a 600w Pioneer hi-fi amp to drive a small desktop 2.0 setup was probably a little excessive, I replaced all the electrolytic's with better quality ones and in the case of the power input cap one of over twice the capacity of the stock, its a far more sensible setup for me.
It's a $20 amp that actually sounds pretty good driving small bookshelf speakers. Upgrade the power supply for about $8 and it gets even better.
hi what power supply do u recommend what amerage my lepy lp 2020a is 13.5v and 3a amperage and when turning up the volume on the amp i hear a big pop and static noise increases.
The advertised 20 watts is supposed to be the total wattage, not the wattage per channel. Your test showed that this amp put out around 9 watts per channel, so it is close to 20 watts advertised total when the load is 4 ohms.
No, the box specifies W per channel - and specifying anything else would be INCREDIBLY misleading and not at all excusable.
The 20W per channel is marketing B.S. Some manufacturers used to call this "Music Power" on the basis that most uncompressed music is quiet with occasional peaks. The amplifier, power supply, and speakers may well supply short peaks of (highly distorted) output which the addled human brain registers as part of the performance. It is the power of these peaks that the salesmen use like snake oil to charm the customers.
Your brute force calculations provide a much more realistic approach to RMS power output, especially as you link your measurements to the cusp of drastic distortion.
Wow, I'm amaze when you short the speaker terminal on Lepai and still working very well.
My Marantz PM-450 (80's amplifier) blew on all power transistor and transformer when accidently short speaker terminal. And cost more money to repair it.
+Faisal Kadal 30 years ago, protection circuits were a lot more expensive and difficult to implement without causing issues with the sound quality. Today's integrated amplifier ICs are really easy to protect, since you just have everything in a single chip, and performance isn't as critical.
+FFcossag I see, thanks for explanation. I think now modern electronics much more safe than old electronics.
+FFcossag I see, thanks for explanation. I think now modern electronics much more safe than old electronics.
Most modern digital music releases are highly compressed (see "loudess wars") so quite high in-room SPLs can be achieved with an amp like this. However, play a decent 'vintage' recording/transfer, one with a high 'crest factor' (large dynamic peaks on percussion for eg), IOW a genuine hifi recording, and you will not be able to get the same SPL's without clipping and hence audible distortion. I've noticed this limitation with all the Tripaths I own (Lepai TA2020, Indeed TA2020, SMSL TA2021).
The amplifier can handle 20 watts per channel at 10%THD. The power supply is just undervolted to fully drive the TA2020 in the amplifier.
The TA2024 in the 2024A series is meant for 12 volt input.
In sort, they supplied an under-powered power supply.
The TA2020 is built for 12 V as well (and it'll go up in smoke much above that), I'm not sure what you're on about.
FFcossag No. The TA2020, TA2021B and 2024 all use the same circuit. The packaging is just different so that the 2020 and 2021b can support an additional heatsink and thus support higher input voltages, leading to more output power. Check their datasheets.
By all means. If you had done the same, you would have seen the absolute maximum 16 V supply voltage rating for the TA2020. That means that it'll likely go up in smoke and flames once you exceed that.
www.e-ele.net/DataSheet/TA2020.pdf
FFcossag Yeah, that's what I'm saying. The TA2020 is mean to work at ~14.5v thus reaching higher output. The 2024 is meant for 12v input. It's just that the lepy on your video is supplied with a 12v power brick.
ExPsy I'm quite certain that I ran this test at 13,5 V. The difference is quite marginal either way; 15 or 20 W per channel both sound quite the same.
Hi. Thanks. Brilliant teardown. Do you know if it is possible to damage this amp by connecting one of the speakers out of phase? Blue light but no sound from the lepy after doing this (by mistake) .. but still cant believe this could have zapped the lepy.
I have one of these amps and it does not have this self-oscillating problem. I paid around $25 for mine and it came with the power supply.
hi how would this be possible to use with headphones what would i need i tried plugging headphones in but when i turn volume up they just play through the speakers.
I really like your review. I wonder if you would comment on the component values of the volume control modification, including the resistor values as the bands are hard for me to read on the screen. Also would like to know the brand of capacitor you replaced. Thanks for your channel. It is a real service.
+Donald Ferguson Sorry for the late reply, I never noticed your comment. The resistors are 5600 ohm, and I -think- I used a 20k linear potentiometer as a replacement of the original. The original capacitor in the unit was something entirely generic and probably brand-less, as were all the capacitors inside of it.
i have lepy lp 2020a with 13.5v and 3a amperage power supply for the amp and a 75w studio monitors music plays when turning the volume up on the amp i hear a big pop cuts out for about a second then does it again and the static sound increases how do i fix could it be the power supply what volt and amperage plug do u recommend so i also dont get distortion. the amp is a lepy lp 2020a and speakers are eris e4.5 presonus
What power difference (if any) would you see if the only waveform you had were a square wave, not a sine wave? That's all I have, something I made up from a 555 timer IC.
There are loads of these little amplifiers, people do not realise that many of them simply are NOT stereo. They are also not a Tripath chip, maybe a TDA7498, but a amp running in bridged mode.
The output is then even weaker: As little as 2.5W.
There are also loads of the little TDA2030 panels about. I wonder how they would perform under the same test conditions? I believe that you can get one for as little as US $1.60, but that is not for a cased product.
I noticed mine cuts out and distorts sometimes at high volume when there is a lot of bass. Other than that I think it sounds really good. It is MUCH better than the LP-838.
Hello! Great test and teardown! Very complete! I have a 2020A+ as well, I think maybe a little newer model PCB than yours, but the thing my vol potentiometer is (just as you mentioned here) having some internal connection trouble, I think, because the sound scratches on the left channel as I turn it and I notice the output voltage on the left is way over what it should be. Anyway, I was wondering what 20k pot you put in and where you found it?! I live in France and can't find a 20k pot anywhere!
+Xavier Bonet I used a generic linear pot off of Ebay, I just picked one that looked kind of similar to the original.
Great! Thanks for the response! And so the resistors you put on the back were to turn it into a log pot?
I'm having some trouble with electrical noise on mine when I touch the dial or the casing, is there anything you can recommend to get rid of this?
Thanks again for all the good info!
best thing i could advise is buy two of these amps one for each speaker (bi amped)
I NEED YOUR HELP I AM A BEGINNER I'VE BOUGHT THE 2020A+ AND THE UPGRADES FROM A NEXT UA-cam VIDEO BUT MY PROBLEM IS I CAN NOT OPEN IT. ALL THE SHOPS I WENT TO COULD NOT OPEN IT THE KEY IS VERY SMALL I COULD NOT BUY IT ANYWHERE. HOW DID YOU OPEN YOUR. I SEE YOU GOT CROSS HEAD SCREW IN NOW.CAN YOU GIVE ME YOUR LIST OF MODIFICATION AND PICTURES AND KEY LINK PLEASE THANK YOU AND NICE VIDEO OR EMAIL ME
FFcossag More Questions. A common compliant with this amp is the power supply that is supplied. I recently upgraded my computer power supply with a new one and intend to use the old one to power the Lepai, this is a 12v 16 amp source that was the 12 volt source for the mother board, I was thinking this would be a good stable power source for the amp, do you see any problem using this. Thank's, Less Opinion
Nice little amp, driving some old KLH's connected to HTPC.
I have connected Schiit modi's RCA output to RCA inputs on Lepai. I also connected 3.5mm audio cable to 3.5mm input on Lepai this way i can switch between my laptop and iPhone to play audio. Is this connection fine? Or will it damage any of the components?
It's unlikely that you'll damage anything; the outputs of tiny devices like headphone amplifiers and phones tend to be short-circuit protected. However, you are connecting the output of your telephone to the output of your Schiit, and connecting outputs to outputs is something you should never, ever do unless you know what you're doing.
When you play something on one of your devices, it will essentially try to over-power the other one (which is working hard to keep its output at 0!), which might lead to distortion, heat, and reduced battery life.
very nice explanation
I have one on my scooter and it works fantastic
Wery good video quality ,thanks !.I wonder what inside this popular T amps.
How about testing the Lepai LP-168HA amplifier? That would be interesting!
That thing doesn't even seem to be Class D; i.e, probably built out of trashed car stereos.
what are the best mods that can really improve the lepais sound quality that you know of? great video by the way, very informative
Thank you. The only thing I'd recommend, is running it off of a 13,5 - 14 V power supply, and not a 12 V one. It's built well-enough not to produce much in the way of audible artifacts (from what I've been able to measure), so I can't recommend doing any internal modifications for the sake of sound quality.
FFcossag english is not my 1st language so I cannot say I understand your vdo completely. however, I'm quite interested in your recommendation on running it off a 13.5 - 14v supply, instead of 12. could you briefly explain why that would be an advantage? thanks in advance :)
Oak Adthapol N. The higher the input voltage, the more power you get. It will go louder on 14 V than on 12 V.
FFcossag and does it mean that at the same loudness, 14v will be less distortion than 12?
Oak Adthapol N. More or less, yes. At very low volumes, it doesn't matter, but once you turn it up even a bit, 14 V can make all the difference.
, I purchased a 19 volt / 2.1 amp power supply and a
24 volt / 5 amp power supply and I purchased two of the newer model
the Lepai 2020ti.
which is class d and not the original class T.
Would this work well to drive a pair Infinity Reference Coaxial 3.5" speakers ?
Not really, the LP-2020 is not very hi-fi.
Thank you for the video. I was wondering, where on the volume knob would the amp be reaching around 5 - 7 watts? I just want to know the maximum safest volume knob location. I have been keeping my volume below halfway just to be safe, but if it can handle anything past that it would be great. Thank you!
Output power depends on your input signal. There is no "maximum knob position". Just don't play it so loud that it sounds bad (treble gets modulated by the bass).
the power supply i use universal ac adapter 15v 3.5v 90W MAX MADE IN CHINA AND I LIVE IN ENGLAND THE MAX I HAVE PUSH IT TO IS THE ONE O'CLOCK POSITION.I AM WAITING TO MODIFY IT ONCE I GET IT OPEN.I HAVE DONE MY HOME WORK. I HOPE THAT HELPS DO NOT PUSH THEM
The volume pot on the amp is garbage, that's pretty much the only reason I'd buy a higher end model 2020/2024 amp.
The volume pot on mine went out and fucked the sound up hard, sprayed it with some lube and it's back to normal, the pot has terrible feel though.
Could you explain why 5 clean watts per channel at 1khz isn't actually 5wpc due to the dynamic range of music, I think that would help listeners better understand the capabilities of this amp and all amps in general.
5 W/ch. is 5 W/ch. no matter how you turn it. The crest factor of music remains the same no matter what amplifier you use, and as such, the average power output will always be set percentage of your peak power (of course depending on the music you listen to). As such, it is rather pointless to state any realistic average power figures, in my opinion, since the point is to bring forward a number that is easily quantifiable and comparable across different amplifiers.
Can I bridge it to power only one speaker from both channels?
+voytek m No.
FFcossag Thanks for your review!! I must admit that I have very limited knowledge of electrics in general. I found your video while searching for a way to run one of these little thing in mono. Although you talk about it around 7 minutes in, I didn't quite understand... So is it possible to bridge this amp to run a single speaker in mono?
testacorsa150 It's NOT possible to bridge this amplifier, since each channel already is made up of two bridged amplifiers.
Thanks a lot for your fast reply. I am now looking into a ta2024 amplifier board on ebay, and looking into paralleling the channels instead. No idea how, and if it is possible yet. You are most welcome with any input on the matter :)
testacorsa150 It will not work. You can't get more than about 5 W/8 Ohm or 17 W/4 Ohm out of a "12 V" amplifier that doesn't have a voltage booster (like a large car amplifier). That's why people often use 4/2/1 Ohm speakers in vehicles.
FFcossag Thanks again, you are a great help - I will drop those plans then :)
I am building a 5 liter jerry can portable speaker. I have a single pioneer ts-e2090 speaker, and will drive it with 2x6V - 4,5Ah batteries connected in series. For the amp, the best bet for now is this little wonder: www.ebay.co.uk/itm/161377488531?_trksid=p2055119.m1438.l2648&ssPageName=STRK%3AMEBIDX%3AIT
Your input is again more than welcome!
testacorsa150 A Lepai is going to be a lot better than that thing. It's linear, so it's going to run hot and give you poor battery life.
Hey so I am getting a lepy and I have a lepai . Can I bridge a subwoofer with 2 amps ? So I want to put the negative in lepy and positive to lepai and I will get a 3.5 splitter can I get more power if I do that ?
No.
FFcossag
greeting. I own a pair of speakers at 2 ohms. I also have hand made amplifier germanium 2x10 watts. the instruction writes on LEPAI amplifiers that can work at 2 ohms. HAVE YOU DONE measurements at the low impedance. I am very interested to buy this little miracle.
The Lepai CANNOT drive 2 Ohms. The box lies, the chip it's built around is not designed for 2-Ohm loads, and running those risks destroying your amplifier.
FFcossag ok, thx for your replay. can you recommend some amp 20 watts that works at 2 ohms?
Marko Vlasic I'm afraid I don't know of any such device.
Marko Vlasic you might ask yourself
This type can be used for a bass speaker 25
400w to 500w which is not ?
Marko Vlasic you might ask yourself
This type can be used for a bass speaker 25
400w to 500w which is not ?
run voltage up to 13.5 input and add a capacitor on the input then retest...?
I did that in my written review, you can find a link in the description of the video.
Hi, its a great review and test of this amp! Do continue!
I need some help tho, wondering if you can help me out...
My lepai lp-2020a+ just stopped working yesterday.. I think it was due to wrong polarity, i connected my 12v 5A battery, to the amp, and found out i put - on + and + on - for a split second, when i was testing whitch way would work. after i found out what was what, the led light got on. But no sound was send out to my speakers and it just didnt play any sound..
It worked before i cut the DC adaptor wire and connected it to the battery. But now it dosent. Only the LED light worked..
Could this be the Capacitor that got broken due to wrong polar?
- Steen
I strongly doubt it's only a capacitor; if it were, chances are that it would still work, albeit poorly. It's more likely to be an opamp, or the amplifier chip itself.
FFcossag But how can it become broken just after a second of switched polarity?
Could there be other main reasons it does not work? Nothing is burned in there or looks broken. And would it fix the problem if i change the chip?
If it is the OP amp, how can i fix that?
Thanks
Steen Zou It takes considerably less than a second to break a chip like that. I can't say for certain what has broken, I'm afraid you're going to have to troubleshoot that yourself. If it is an opamp, it's only a matter of desoldering it and swapping it out.
Great vid.
Unit faults aside, 100 hours of burn in is a good rule of thumb. And given the low usable output, speakers rated at around 92db/W would be a good match.
Thank you. However, save for finding production faults, and perhaps getting the initial scratch out of the potentiometers, there exists no basis for assuming that such thing as amplifier "burn-in", exists. A poor amplifier when new, will be a poor amplifier at ten, a hundred, or a thousand hours still.
FFcossag True.
There is some rational in a few hours of burn in though. Component parameters do change over time.
So its possible that an audio device can sound better or worse over time.
I'm very much intrigued by these Tripath amps. A few manufacturers seem to have produced astonishing examples.
fatcat2939 Component parameters do change over time, what I react against is any claim about them doing so drastically enough to audibly affect the sound in a manner of a hundred hours; that's simply not true unless the components in question are faulty. In such a case that faulty components are installed, they're furthermore unlikely to impact the performance of a device positively.
True
FFcossag, Thanks for the video it's quite informative. As to the volume mods could you be more specific as to the parts used as I am a electro twit. Questions are as follows
1. Vol pot. is this a specific size or type, how do I specify when ordering parts other than it's 20k linear. Please include the tone control pots also.
2. I could not quite make out what you said as to the reason for the resistors soldered to the backside of the board in the volume circuit could you give a brief explanation
3. P/S I am from Missouri USA what language is it that you speak. Ha Ha
+Less Opinion This potentiometer is a "China standard". You'd have to look at the mechanical characteristics of it and find one that matches to do it right, but in this case you can just go on Ebay, type in "20k linear stereo potentiometer", and basically all of the ones that look the same as the original will fit.
The added resistors are there to change the linear potentiometer to a logarithimic one. This is because linear pots tend to be more reliable than logarithimc ones, but you want a log response for a volume control. You can just use a log pot and omit the resistors if you want to.
Your computer power supply will work fine, but it is grounded, so if you connect the amplifier to another grounded appliance (such as a computer), you might get noise and hum due to a ground loop.
I do not know what language I speak, except that it isn't yankeenglish. ;)
Cheers
hey i just got one of theses and its driving me crazy, when its powered on with no input, the speakers make a low static noise/hiss, and when i connect an input its still there with my music,i read online that it could be bad grounding but i honestly dont know. can you please give me some advice. i have tried replacing all the wires and even the 12vpower brick
+saad abass There's some internal fault in the amplifier, most probably. It's impossible to tell, but it isn't supposed to be like that.
+FFcossag if i open it up and send you some clear pictures could you possibly see the problem, hahaa i know its a long a shot but its worth a try i guess.
saad abass I'm not sure it's worth bothering, I'm afraid. Issues like that are rarely if ever visible to the eye. You'd have to go through it with a meter in order to say anything, really.
Can you test this amp? www.amazon.co.uk/gp/product/B00JGP3HMS/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
what about a 2Ohm load
If you have two of these, is there a way to combine them to one? I would split the audio cable and double the speaker cables, but this is of course without any knowledge of electronics, I would probably end up with smoke and fire :)
No, you can't connect one speaker to two of these. If you just split the input cable, you can play the same sound through four speakers.
OK , thanks for the advice :)
Thanks, Is it easy to remove the LED light? Can I just cut the wire to it?
yes.
Hi I hope you can answer this.. i recently got a lepai 2024a which seems to be the same as the 2020a but I guess I cranked it up too high or something and the sound quit. After that, the blue light would only fade on and off. I tried unplugging and everything... All it would do from then on is the light fades in and out repeatedly and no sound so i sent it back and got a 2020a now. Can you tell me if that problem with the light fading in and out is easily fixable as in a way to reset it or did the amp just fail? Thanks .
+cottonproductions Something has gone wrong, it's impossible to tell just like that, I'm afraid.
chances are thats a capacitor problem
one question my lepai volume knob is fried where do i get a replacement
Ebay, just search "20k potentiometer" and pick one that looks the same.
This amplifier is powered by Sanyo Linear IC model LA4636. 11 Watts RMS 2-channel BTL AF Power Amp. Accept 8 OHM speakers, and 10% of THD.
The Lepai LP-2020A+ is built around a Tripath TA2020. I don't know where you got that Sanyo IC from, but it's incorrect.
FFcossag datasheet.eeworld.com.cn/pdf/SANYO/135220_LA4636.pdf
FFcossag Certainly the power of any amplifier and distortion varies according to the impedance of the speakers. In this case, with 8-Ohm speakers the power of this mini amp showed 5,152 W. at 1% THD (measured with Velleman HPS50) even though the manufacturer named TRIPATH indicates 8W.
***** My measurements align reasonably well with the stated specifications (I measured 6,67 W in my written review into 8 Ohm at 13,5 V supply, whereas the chip is specced for 7 W). Keep in mind that the clipping power depends on the supply voltage, and will be lower at 12 V.
Hi, I'm completely new to this but can this be bridged to give a mono output with double the power
icantfindspace The short answer is no. You can find the long answer somewhere around these comments.
+FFcossag actually, you can get a stereo to mono output wire to convert it, so the short answer is..........Yes.
Tee Bee You can NOT bridge this amplifier, since each channel already is made up of two bridged amplifiers. You can use a mono adapter to make both channels put out the same signal, but they will not put out more power than in stereo mode.
no one said you had to bridge it to make it mono.
+Tee Bee The question atop this comment thread quite specifically refers to bridging.
can someone put this into simple terms for me please? how many watts comes out of each channel? is it safe to run 10 watt speakers on this amp (6 ohms) thanks
It's fine as long as you don't play it so loud it sounds bad.
FFcossag thx
What are you even playing from 0:06 to 0:12?
Nothing, that's the point.
@@FFcossag haha I can't believe how dumb my comment was
Can I run this lepai with a 12v or better yet, a 14v total rechargeable battery. Also, will the output be the same in ac or dc.
The input voltage should not be over 14 V, ever. A 12 V nominal battery is probably the highest safe battery voltage you can run, since a battery always is much higher than its nominal voltage when fully charged. There's basically no difference between voltage coming from a wall wart, or coming from a battery, so the unit will work identically.
Thanks very much for the reply.
allan soria you might ask yourself
This type can be used for a bass speaker 25
400w to 500w which is not ?
The build quality of these cheap Lepai amps are so inconsistent.
Pha Q *is
5.28 watts at 8ohm and 9 watts at 4 ohms, that is terrible. I built a TDA 2030 that puts out around 15 watts and it was 6 dollars.
Nobody designs a volume control to alter feedback of op amp, its just not workable! Are you sure you didn't mis-read the traces?
Whether or not something is workable. generally has little impact on the Chinese design process. There isn't really any other way that a dicky volume control would cause that horrible oscillation issue.
FFcossag
Aaaaarrghhh..I subscribed....
will any 12v dc wall plug work on this?
More or less, as long as it can deliver an amp or two.
What's the difference to this and the 2024 a+ version?
The non-A+ is really shitty.
Ok thanks
so the 2024a+ should be good? (if slightly lower output power)
jsv
I wouldn't buy anything 2024 based.
I'm interested in why you wouldn't buy a 2024 based system?
I'm waiting on delivery of a 2024A+, luckily I only paid £10 for it.
Great video, most speaker manufacturers simply sum the maximum output powers of the different channels, and call this the power output. Maybe this is what they meant? It's still dishonest I believe
for $20 you have made a lot of "cheap" comments.
The treble controller only work on the right channel lol. 24:10
There is no more lepai only lepy
Ryan Lin that's not true actually. The place to buy real Lepai amps is Parts Express.
I bought my lepai 2020a+ on taobao with a 6 amp 12 volts for only 100 yuan . and then i bought my lepy 2024a+ same thing for same price!!
"Made in Bukang" where the hell on earth is Bukang?!
That Lepai is a fake amp. he real ones have a blue LED that goes all the way around the potentiometer and the color is different.
operationTF7 You have a keen eye. I replaced the two blue LEDs for one green, since I just don't fancy blue LEDs in general.
oh,ok. Yeah, a lot of people complained about the blue LED being irritating to the eyes.
+operationTF7 yeah i agree. i replaced mine with warm white ones. looks much more pleasnt. however after obtaining better equipment over the years i eventually hit that leapi with a hammer
smallenginedude71 I wish I had that much of an inventory that I could intentionally destroy a portion of it and barely loose any value! XD
operationTF7 i accidentilly reversed the polarity on the 12v input so it was broken anyway. i wouldnt kill something that was working well.
very Nice Video THX and maybe Kitner 500w = ) real only 30w sin
+kocko66 the kinter "500" watt will do 13 watts RMS @ 4 ohm
u are aweaome
Thank you.
if it don't make me ears ich..It aint shit.
I think you bought a dud - Bad heatsink, treble only on 1 channel, bad pot. Get another one and do another test.
+Hamish Spencer Out of all the people that could have gotten a dud, I'm glad I did; it highlighted the potentially devestating issue with the volume pot, so that people know what they're getting into.
Thank you for pointing that out. I just wonder if clipping and power output levels are also faulty on yours. If so, it would be nice to see the 'real' values.
Hamish Spencer No, the output power values are what you'd expect to get out of the amplifier IC. They're limited by the 12 V supply voltage.
Why do people like these cheap horrible things? There are way better T-calss amps on the market for the same or a little bit more.
+MasterGravitron The Lepai was the first, and it's just got such a big reputation going for it that it's hard to break. The newer TPA3116 based stuff that's coming out is going to replace the TA2020 soon enough.
Please name it
these are a pretty terrible amplifier.
everyone is fawning over these things lol.. its cheap junk
i have lepy lp 2020a with 13.5v and 3a amperage power supply for the amp and a 75w studio monitors music plays when turning the volume up on the amp i hear a big pop cuts out for about a second then does it again and the static sound increases how do i fix could it be the power supply what volt and amperage plug do u recommend so i also dont get distortion. the amp is a lepy lp 2020a and speakers are eris e4.5 presonus