I must agree with both of you.
Lepai is a great amp for the ones that are starting with diyaudio . It costs $ 10,00 so you can play around with it without any remorse and if you want to challenge yourself and try to make it play on the same league as AMP6-BASIC KIT ( $ 39,00 ) then you have $ 29,00 left to buy components and learn more. If you fail then in the worst case scenario you lost $ 10,00 and can keep the components and the ugly case
I just started on this diyaudio world and to me Lepai is a great amp since I want to learn fast and having a trouble free unit might not be the best choice because most of the time we learn more from our mistakes.
I learned alot reading the ta2020 datasheet and I must say that at the first I tough I was not skilled enough with electronics to read the datasheet and find a solution to bypass the tone and op amps but I was wrong and I loved to be wrong.
I will distribute those amps on my home doing ambient sound in the bathrooms and rooms while for garden and living room I have two sure tk2050 4x100 on their way to my home and even an Arjen Elder MKII for my desktop.
In the end it is up to what you want to anchieve and what will fit better your needs while not getting your wallet empty .
[]'s
I believe the attraction is buying a cheap simple amp that you can mod by exchanging a few parts and hopefully by time achieve something like the AMP6. If you buy the AMP6 and it's as good as people say, there's not much to modify.
As an electronics noob I've been debating over this myself but I've chosen to build my own amp based on the schematics in the TA2020-sheet instead of buying a Lepai. Many things can go wrong and it would definitely be easier to buy the Lepai and change parts one by one but I'll take the chance.
As an electronics noob I've been debating over this myself but I've chosen to build my own amp based on the schematics in the TA2020-sheet instead of buying a Lepai. Many things can go wrong and it would definitely be easier to buy the Lepai and change parts one by one but I'll take the chance.
I purchased four for $ 40,00 plus shipping ($ 10,00 ) from aliexpress.com but i'm not going to deal with this site again even if they pay me to.
Seller is a stone faced liar and has several stores there :
Zhongshan Koqi Electronics Manufactory
Tiger Ecommerce Co. LTD, TYFUNG TRADE CO. LTD.
John Liao B
John Liao a
My order needed 20 days to get sent and a total of 90+ days to arrive. I purchased from the most graduated seller there but had big headcaches dealing with him and aliexpress "buyers protection" so my adivise to everyone is :
Keep your wallet away from this place or maybe try products listed as fulfillment by aliexpress but be aware that their customer support sucks to a whole new level.
Also any of you know where I can buy good components with honest $hipping ?
farnell newark, mouser, digi-key, madisound all want to charge me $ 38-45 to ship a single cap.
[]'s
For small orders I use rs components as they dont charge for p+p
RS Components | Electronic and Electrical Components
Thank you, Virpz. I just did the same thing. Works great.
Just a note to all, this will bypass the volume control. That's fine for me because I use it as a "power amp" with an external pre.
Just a note to all, this will bypass the volume control. That's fine for me because I use it as a "power amp" with an external pre.
That's it.
I put my "dead" unit components on board again and gave it a try first connecting an vu meter to the outputs since I don't own a multimeter and the neddles responded as they should to the volume set and power. I did that to avoid blowing up my speakers in case everything was wrong
To bypass op amps and tone controls on TA2020a+ pcb 101110 you must remove c30, c31, c20 and c21.
Then just connect c31 positive to c21 positive and do the same with c30 and c20. Yes, the caps orientation for c20 and c21 are wrong printed on the pcb.
As you can see I used the same bipolar coupling caps that wer originally placed at c20 and c21. I have mundorfs, metal film, nichicons and new inductors on their way to my home already.
Shame on me for asking you guys how to bypass it. It needed only a look at the schemathic of the old lepai, the ta2020 datasheet for pinouts and ta2020a+ pcb. I feel ashamed for asking on how to do it.
Oh i'm pretty happy with the result. No clipping, no hiss I can increase the volume much further with the plesure of having a much better experience. I almost can't believe it is the same amp. I don't need op amps to play louder with the expense of heinous sound quality .
Forgive me if my english su*ks
Hey
I will get a 10 $ refund for the lepai not functioning anymore. A new ta2020-020 chip is 6.50 shipped on ebay so I'll hope it works. Before ordering it I'll try bypassing the input stage like Virpz did and checking connections just in case it wasn't the chip that fried.
Does anyone who knows more about the relay's function say what causes the relay to not click on anymore?
I will get a 10 $ refund for the lepai not functioning anymore. A new ta2020-020 chip is 6.50 shipped on ebay so I'll hope it works. Before ordering it I'll try bypassing the input stage like Virpz did and checking connections just in case it wasn't the chip that fried.
Does anyone who knows more about the relay's function say what causes the relay to not click on anymore?
Good site but shipping hurts me.
Thank You
Very appreciated.
Thank You
Yes, i'm planning to use the units as PA also but 'im also trying to figure out how to get an volume pot .Thank you, Virpz. I just did the same thing. Works great.
Just a note to all, this will bypass the volume control. That's fine for me because I use it as a "power amp" with an external pre.
Hey
I will get a 10 $ refund for the lepai not functioning anymore. A new ta2020-020 chip is 6.50 shipped on ebay so I'll hope it works. Before ordering it I'll try bypassing the input stage like Virpz did and checking connections just in case it wasn't the chip that fried.
Does anyone who knows more about the relay's function say what causes the relay to not click on anymore?
The relay not switchin on can be any faulty component that prevents the signal to reach the relay. Anything connect before the relay can do that. Like capacitors and resistors. Give a it a try by replacing C9.
Good luck
It took a while to change out the caps, so I can't really compare. It's not much different; but I wish I could go back and forth quickly. I may put the original caps back, or see if I can get suitably small film caps, because I want to close up the box.
Nice little amp, glad I got it. It works well with my small monitors, especially the JBL Control 1 Pros.
This amp has more low end compared to my Trends TA-10.1, and I think it has more top end too.
The noise from the amp pretty much went away when I switched to my Trends 3A supply, and did away with the op amp.
I don't play the small monitor system loud, so there is plenty of power.
Nice little amp, glad I got it. It works well with my small monitors, especially the JBL Control 1 Pros.
This amp has more low end compared to my Trends TA-10.1, and I think it has more top end too.
The noise from the amp pretty much went away when I switched to my Trends 3A supply, and did away with the op amp.
I don't play the small monitor system loud, so there is plenty of power.
just got the t2020+..
i read the last 10 pages for at least 10 times already..
order the capacitors according to XtremeRevolution.
any recommendations for the op amp??
whats the differences between changing them and bypassing them?
if bypassing, is it bypassing 1 or both of them??
if changing, what is a good choice??
i read the last 10 pages for at least 10 times already..
order the capacitors according to XtremeRevolution.
any recommendations for the op amp??
whats the differences between changing them and bypassing them?
if bypassing, is it bypassing 1 or both of them??
if changing, what is a good choice??
If you want to improve the sound on the Lepai
-play with the inductors, not the caps!
In these class-d amps expensive foil caps doesn't make any difference, exept the input filter (electrolytic) cap that shall be as big as possible.
Replacing the inductors makes the Lepai sound much like an AMP6
-play with the inductors, not the caps!
In these class-d amps expensive foil caps doesn't make any difference, exept the input filter (electrolytic) cap that shall be as big as possible.
Replacing the inductors makes the Lepai sound much like an AMP6
Good question. I assume both op amps were bypassed. A look at the schematic will tell us. Do you have a link to one? I could only find this older v schematic from djnemesi:
That post is here.
I can't find the 1.75uF caps.
But it appears the input hits c30/31 first on the 2020A+, then goes to the pot, accounting for the bypass including the volume control. That's not the way it is on the older schematic. I read in another forum that those caps are not good for audio applications.
C20/21 should be the coupling caps. But I can't find anything of that value on this schematic. Wouldn't they connect to or near pins 10 and 13 of the Tripath chip? I'm out of my comfort zone, dunno.
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