Lepai T-Amp with TA2020

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suggestion !

I use the blue beauty Alps one in all my pre-amp stages. But it is worth to put
it only if you have done all the mods on the Lepai, you will have slightly better channel separation with the blue Alps but don't expect miracles.
On my Lepai i just bypassed the pre stage with 2 2.2uf theta mkp caps and use it as small power amp paired with an external pre-amplifier or ipod/iphone/mp3 player (which have adjustable outputs). I kept Lepai's pre-stage intact for connecting a standalone cd player.
It is a killer small amp after the mods " + plus" it will help you a lot understanding how the 2020 tripath chip works.
All amps should be placed in a basic metal enclosure if you want to put them in a nice wooden box. You may not have EMI interference in your house but if you take your amp elsewhere, you might have problems. Try it first without the metal enclosure & put your ears close to your speakers to see if you hear any weird noises.

Vassilis

The one about what I am taking is this http://www.ebay.es/itm/170683788782#ht_1944wt_1117 only 7$

My Lepai volume potentiometer is a piece of crap, its not centered, makes noise using it, and the knob moves in the vertical axis by 1mm u_u

But thinking about it, I think that better will remove one of the tone potentiometers and replace the volume by one of them.

Another question, what do you think about wood enclosures?, I'm thinking about making a simple one, just to improve the amp appearance. Will be needed to make some kind of metallic cover for the amp to avoid EMI?
 
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All amps should be placed in a basic metal enclosure if you want to put them in a nice wooden box. You may not have EMI interference in your house but if you take your amp elsewhere, you might have problems. Try it first without the metal enclosure & put your ears close to your speakers to see if you hear any weird noises.

Vassilis


Well now I have some strange interferences in my signal that are coming from the source and cable (a Macbook with a cheap cable that I have at home), probably getting a better cable will improve this…

But anyway I will use a basic metal enclosure inside the wooden box, I asked this because I saw lots of DIY in wooden box without any visible metal EMI shield and just was wondering if for any reason aren't necessary.
 
The one about what I am taking is this http://www.ebay.es/itm/170683788782#ht_1944wt_1117 only 7$

My Lepai volume potentiometer is a piece of crap, its not centered, makes noise using it, and the knob moves in the vertical axis by 1mm u_u

But thinking about it, I think that better will remove one of the tone potentiometers and replace the volume by one of them.

Another question, what do you think about wood enclosures?, I'm thinking about making a simple one, just to improve the amp appearance. Will be needed to make some kind of metallic cover for the amp to avoid EMI?

I have tested rotary pots for volume control and I didn't liked the result. Your ear is logarithm so you better get one log pot for volume control.

Maybe the moving knob is the chassis of the volume knob not tight to its body, mine was a little loose. Just tight it's arms.

On mine units the tone controls were 50kx2 pots. They should work fine.

I love wood enclosures, I have my not-finished-yet Tk2050 on wood and I like the result. In my case I insulated everything but used no metal walls to block EMI and the amp is quiet.

disco59232348.jpg


I revised the lepai lp2020A+ schematic for the volume pot and decided that if you still have op amps circuit on the board you better not ground the volume pot in the holes or things may get noise and weird. I can't confirm because the board I did the mod have no op amps circuit anymore but you better go for the pcb to ground.
 
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I have tested rotary pots for volume control and I didn't liked the result. Your ear is logarithm so you better get one log pot for volume control.

Maybe the moving knob is the chassis of the volume knob not tight to its body, mine was a little loose. Just tight it's arms.

On mine units the tone controls were 50kx2 pots. They should work fine.

I love wood enclosures, I have my not-finished-yet Tk2050 on wood and I like the result. In my case I insulated everything but used no metal walls to block EMI and the amp is quiet.

http://i9.photobucket.com/albums/a83/vulturex/disco59232348.jpg

I revised the lepai lp2020A+ schematic for the volume pot and decided that if you still have op amps circuit on the board you better not ground the volume pot in the holes or things may get noise and weird. I can't confirm because the board I did the mod have no op amps circuit anymore but you better go for the pcb to ground.

Nice tip, if I'm not satisfied with the replace I will try to find a logarithmic pot instead of a linear one ;)


Now I have the opamps bypassed, but I was planning to add a switch to be able to use the tone controls when necessary, so I will take note of your tips.

Thanks
 
Hi folks Been following the thread here and on several other sites and just wanted to chime in - I've been working on my Lepai 2020+ and was having trouble finding the inductors here in the US.

I just wanted to pass along a good source I located.. a bit higher spec (6A instead of 3A), but seem to fit the bill nicely. Bass seems quite a bit tighter and defined.

Here is the link for the toroids:
10pcs 10uH 6A coil wire wrap toroid inductor choke | eBay

I let the seller know that I would be pointing more folks his way.

For my Mod - I bypassed the op-ams and tone /volume circuit as well as swapped out the power cap for a 10,000uF. Amp is amazing now.

Here is a vid I made just prior to the inductor swap - I'll update it with the final inductor mod soon when I have time.

Lepai Tripath ta2020+ Class-T amp modifications - YouTube
 
a highly rated amp after the mods

Those inductors will do the job. Here is another one for you : Inductor 10uH 10 uH +/- 10% 5 pcs | eBay i used these ones and moved the sound to another level .

With a rate of 10 i give 10 to this amp. It has become an addiction for me. I listen to music in mid levels with lepai & use my big stereo for high levels :eek:

Hi folks Been following the thread here and on several other sites and just wanted to chime in - I've been working on my Lepai 2020+ and was having trouble finding the inductors here in the US.

I just wanted to pass along a good source I located.. a bit higher spec (6A instead of 3A), but seem to fit the bill nicely. Bass seems quite a bit tighter and defined.

Here is the link for the toroids:
10pcs 10uH 6A coil wire wrap toroid inductor choke | eBay

I let the seller know that I would be pointing more folks his way.

For my Mod - I bypassed the op-ams and tone /volume circuit as well as swapped out the power cap for a 10,000uF. Amp is amazing now.

Here is a vid I made just prior to the inductor swap - I'll update it with the final inductor mod soon when I have time.

Lepai Tripath ta2020+ Class-T amp modifications - YouTube
 
hi everyone, first pot here. I have 2 Lepai TA2020A+s. unlike most everyone here I need more bass. Is there a way to permanently add bass within the unit, i.e. modify the tone controls, or better yet, add some "resistors" to have it automatically shelve 10 db at 60 hz?

i have 3 systems in my house. The first is computer>lepai>QLN model ones. it seems like i have winamp permanently boosted at 70 hz, with the preamp reduced equally (to offset the gain). that generates adequate bass on my QLNS.

i have a counterpoint SA3000 + SA220 > energy veritas 1.8. (counterpoints handed down to me, i would never spend that much for amps). my fav setup is the lepai into veritas, which has great bass, but those speakers r too big in my home office where i do most of my listening. i guess it shows importance of matching speakers to amp.

the third is a lepai to energy c6s. it's here that the energys are woefully lacking in bass. i've inserted an audiosource eq b/w the cd player and lepai but don't like having the complexity. im also considering buying a behringer digital eq, and toslink the cd player to the behringer (to keep the signal processing in the digital domain), but figure if i did that, might as well buy a onkyo tx 8255. however i do love falling asleep w the lepai on, knowing it's only sipping watts as opposed to old school amps. sorry for posting so much. my main question is on adding a permanent eq bump on the low end.

thanks, James
 
hi everyone, first pot here. I have 2 Lepai TA2020A+s. unlike most everyone here I need more bass. Is there a way to permanently add bass within the unit, i.e. modify the tone controls, or better yet, add some "resistors" to have it automatically shelve 10 db at 60 hz?
...

thanks, James

swap the power cap... The single biggest effect on the amount of bass. The stock cap is way too small. When I replaced that, I went from no bass below about 100hz, to solid, punchy and defined bass all the way down... I actually have been considering re-eq'ing my room...

Also, make sure your power supply is supplying enough current. If I remember, the stock supply is like 12v at 1.2 or 1.5 A... I swapped for 12v, 5A..

The amp runs out of steam and can't push out the low end without these mods..
 
yeap !

I agree.
I put 4700uf on mine & use a 6A/12v power supply. Amazing amp (after the mods of course).

swap the power cap... The single biggest effect on the amount of bass. The stock cap is way too small. When I replaced that, I went from no bass below about 100hz, to solid, punchy and defined bass all the way down... I actually have been considering re-eq'ing my room...

Also, make sure your power supply is supplying enough current. If I remember, the stock supply is like 12v at 1.2 or 1.5 A... I swapped for 12v, 5A..

The amp runs out of steam and can't push out the low end without these mods..
 
With the original power cap the amp can't handle low freqs at high volume, you can easily see the LEDs blinking because the amp run out of power.

I have also replaced that cap by adding another in parallel (6800uF + the 3300uF stock = 10100uF, also change the inductor that is in the power line with wire as it limits the current that comes in the amp) and now the amp bass is more deep as it can handle it without any voltage drop, but you should know that its only 20W+20W, it will start clipping if you demand too much power…

What others say that also helps to get better bass response is to change the inductors at speaker outputs.

Changing inductors is more expensive, but people reports that the amp improves dramatically. I'm really thinking about it, as the recommended ones are too expensive (the cheaper that I've found cost 9€, from helder hifi), and there are many others that should provide an improvement in sound quality, but don't know what will have better cost/performance ratio…
 
have a look

I bought these : Inductor 10uH 10 uH +/- 10% 5 pcs | eBay
They did the job, very cheap & the difference was huge.

With the original power cap the amp can't handle low freqs at high volume, you can easily see the LEDs blinking because the amp run out of power.

I have also replaced that cap by adding another in parallel (6800uF + the 3300uF stock = 10100uF, also change the inductor that is in the power line with wire as it limits the current that comes in the amp) and now the amp bass is more deep as it can handle it without any voltage drop, but you should know that its only 20W+20W, it will start clipping if you demand too much power…

What others say that also helps to get better bass response is to change the inductors at speaker outputs.

Changing inductors is more expensive, but people reports that the amp improves dramatically. I'm really thinking about it, as the recommended ones are too expensive (the cheaper that I've found cost 9€, from helder hifi), and there are many others that should provide an improvement in sound quality, but don't know what will have better cost/performance ratio…
 
car audio setup (no head unit) with power inverter

OK, so I'm jumping in here. Lepai (no PS) is on the way. I'm hoping its the latest version (Ordered from amazon, PE was backordered) I've read this thread over the past week from beginning to end and thought I was late to the party. sounds like I might be just in time for a SMT unit that hopefully has a few improvements. This is my firs post and first project like this in a while, but I have soldered quite a few bits together in the past.

So as the header suggests, I want to use this in the dash of my 70's bronco with no head unit and an MP3 to push some crappy old 6x9s (with mud and gear oil stains on the cones...) that are already ran to the rear. It is a classic so no DINN sockets, although the space it will go in looks just right for the size of the amp, I will have to fab up a mount.

I've read lots of posts about the clicking death and then oh yeah I did have it hooked up to the alternator of my cousins drag car, but it was a quick run or whatever... so I'll try not to ask the same old same old.

I have just installed this 750w high/low voltage/current/temp protected power inverter in the cab. I'm not an audiophile, just a nerd so I'm thinking that any old power supply(12 v) plugged into this will be OK. I do have a few questions about this though:

  1. If I find and use a 13w power supply plugged into the inverter, will I be limited to 12V or might it eek out more than 12v (in the case I need more volume/wattage later on, most likely 12v will do fine for me).
  2. What if I find a 9 or 10v PS? since the inverter is low voltage/current protected, would this work at all, or just poorly?
  3. What amperage should I look/test for? I think the supplied is 2amps, but some use up to 5 amps?
  4. I've read in this post about some PS that have adjustable voltage when you open the case. Schazzam! that's the one I want! How do I spot these? What to look for?
  5. Also, If I were to run power directly from the fusebox, what type of inline fuse would you suggest and would it be possible/recommended to put a 12V or 13v regulator to the case of the unit and have the out from that go to the on board power or a short power patch cable to the standard power jack on the back. This would be like a PS regulator piggy backed to the case of the unit?
  6. All these PS questions are because I don't want to fry this thing and seems quiet possible in car audio aps. But that's one of the main reasons I got and installed the power inverter.
One thing that I read in this thread which I found very interesting, but didn't seem to get much attention: The ability to use a patch input cable to bypass the op ams which would allow higher volume without distortion caused by the op am circuits. This seems MUCH easier than slicing leads, removing caps, and such, am I wrong here? In addition, it would keep the controls on the front usable if I decide to pull it for something else later on. I'll try to dig up the post # for that idea and ref it.

If I get it running/setup OK, I would like to do the basic cap mods listed here
Modding the Lepai T2020A+ - Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com
and put some toroids or similar in to push some better speakers later on. I also would like the fault wired to a LED on the faceplate and possibly route the op amp bypass jack on the faceplate.

So with that I must say thanks to all who have posted to this thread over the years and invite questions/comments.

Edit: Just found the links to the arjen helders MIII. I didn't see this option before. Although it cost more, it may be more suitable for my application (has AC/DC ready). But I'll not clutter this thread, just wanted an honorable mention.
 
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go for it.

Be prepared for amazing results. Make sure you disconnect pin no 18 (leave it open). Inductor change will make the biggest improvement to this amp. Enjoy !

OK, so I'm jumping in here. Lepai (no PS) is on the way. I'm hoping its the latest version (Ordered from amazon, PE was backordered) I've read this thread over the past week from beginning to end and thought I was late to the party. sounds like I might be just in time for a SMT unit that hopefully has a few improvements. This is my firs post and first project like this in a while, but I have soldered quite a few bits together in the past.

So as the header suggests, I want to use this in the dash of my 70's bronco with no head unit and an MP3 to push some crappy old 6x9s (with mud and gear oil stains on the cones...) that are already ran to the rear. It is a classic so no DINN sockets, although the space it will go in looks just right for the size of the amp, I will have to fab up a mount.

I've read lots of posts about the clicking death and then oh yeah I did have it hooked up to the alternator of my cousins drag car, but it was a quick run or whatever... so I'll try not to ask the same old same old.

I have just installed this 750w high/low voltage/current/temp protected power inverter in the cab. I'm not an audiophile, just a nerd so I'm thinking that any old power supply(12 v) plugged into this will be OK. I do have a few questions about this though:

  1. If I find and use a 13w power supply plugged into the inverter, will I be limited to 12V or might it eek out more than 12v (in the case I need more volume/wattage later on, most likely 12v will do fine for me).
  2. What if I find a 9 or 10v PS? since the inverter is low voltage/current protected, would this work at all, or just poorly?
  3. What amperage should I look/test for? I think the supplied is 2amps, but some use up to 5 amps?
  4. I've read in this post about some PS that have adjustable voltage when you open the case. Schazzam! that's the one I want! How do I spot these? What to look for?
  5. Also, If I were to run power directly from the fusebox, what type of inline fuse would you suggest and would it be possible/recommended to put a 12V or 13v regulator to the case of the unit and have the out from that go to the on board power or a short power patch cable to the standard power jack on the back. This would be like a PS regulator piggy backed to the case of the unit?
  6. All these PS questions are because I don't want to fry this thing and seems quiet possible in car audio aps. But that's one of the main reasons I got and installed the power inverter.
One thing that I read in this thread which I found very interesting, but didn't seem to get much attention: The ability to use a patch input cable to bypass the op ams which would allow higher volume without distortion caused by the op am circuits. This seems MUCH easier than slicing leads, removing caps, and such, am I wrong here? In addition, it would keep the controls on the front usable if I decide to pull it for something else later on. I'll try to dig up the post # for that idea and ref it.

If I get it running/setup OK, I would like to do the basic cap mods listed here
Modding the Lepai T2020A+ - Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com
and put some toroids or similar in to push some better speakers later on. I also would like the fault wired to a LED on the faceplate and possibly route the op amp bypass jack on the faceplate.

So with that I must say thanks to all who have posted to this thread over the years and invite questions/comments.

Edit: Just found the links to the arjen helders MIII. I didn't see this option before. Although it cost more, it may be more suitable for my application (has AC/DC ready). But I'll not clutter this thread, just wanted an honorable mention.
 
This is what happened to me... there was a short circuit after the op-amp modification .. there after the amp stop responding ..While checking the amp IC using multi-meter there was another elctric shortage between ic pins..After all this drama, the blue LED started to dim :confused:..After inspection we decided there is a electrical short inside the circuit.. (standby current is way over 1 AMP)..now waiting for new ta2020..

What do you think?? your ideas highly appreciated..

Recently I fixed new ta2020 chip board & it looks fine.. no dimming blue led this time.. But when i input the audio signal to it, nothing seems to be coming from amp audio out.. I'm really disappointed about this as i already ordered a extra IC and waited for so long to receive it..I really appreciate your help in this case..
What are the things to check ?
Thanks
 
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