Lepai T-Amp with TA2020 - Page 100 - diyAudio
Go Back   Home > Forums > Amplifiers > Class D

Class D Switching Power Amplifiers and Power D/A conversion

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 4th December 2011, 07:57 AM   #991
diyAudio Member
 
Join Date: Jun 2009
Hi Everyone !
Got mine 2 days ago, it is one of the latest versions. Changed all electrolytics with panasonic FC. Bypassed the pre stage with 2 thetta MKP 2.2uf & added 2 extra rca input plugs, but kept the pre stage for any future needs (if you wanna connect a cd player). Used a 6.3A /18v power supply with a step down dc to dc converter adjusted at the exact 12v. It is an smd board but components are easy to extract. Pin No 18 is still connected to a kind of stupid protection circuit (looks like a resistor with a transistor) but i just cut the trace and left it open. By the way the 3300uf/16v electrolytic at the power supply stage was a used one & leaking (what a Chinese quality check ?) so you better change that and remove the inductor or sort it.
First audition was very impressive. I'm waiting for the inductors to arrive to complete the DIY. Money spend for everything (inductors included) 18euros (with post expenses) for the Lepai amp & about another 12euros for the rest.
Seriously ! I can't believe my ears. This is one of the best inexpensive little amps I've ever heard (but you have to do the mods).
Vassilis
  Reply With Quote
Old 4th December 2011, 09:21 AM   #992
diyAudio Member
 
Join Date: Apr 2006
Location: Reykjavík
Quote:
Originally Posted by vmed_cha_gr View Post
Used a 6.3A /18v power supply with a step down dc to dc converter adjusted at the exact 12v.

It is an smd board but components are easy to extract.

This is one of the best inexpensive little amps I've ever heard (but you have to do the mods).
Tripath is amazing isn't it! Enjoy the music.

Regarding power supply voltage - the TA2020 chip can take up to 14.6V. That's a difference of about 1.7dB headroom. It's not super important, but if you can push the voltage higher than 12V "for free" on your converter, then it's worth doing — IF the other components can handle it (at least a question of the capacitors' voltage rating).

And I must say, sorry for the preaching but I have to - that I find SMD components much easier to extract than through-hole (And soldering them easier too - smd is harder at first, but after reading a little up on techinque and getting the right tools, SMD is actually wayyyy faster and easier!)
  Reply With Quote
Old 6th December 2011, 11:56 AM   #993
Franfj is offline Franfj  Spain
diyAudio Member
 
Join Date: Dec 2011
Quote:
Originally Posted by kristleifur View Post
Tripath is amazing isn't it! Enjoy the music.

Regarding power supply voltage - the TA2020 chip can take up to 14.6V. That's a difference of about 1.7dB headroom. It's not super important, but if you can push the voltage higher than 12V "for free" on your converter, then it's worth doing — IF the other components can handle it (at least a question of the capacitors' voltage rating).

And I must say, sorry for the preaching but I have to - that I find SMD components much easier to extract than through-hole (And soldering them easier too - smd is harder at first, but after reading a little up on techinque and getting the right tools, SMD is actually wayyyy faster and easier!)
The previous version at least has a Zener diode to "protect" against more than 13.5v, so isn't recommended going with more than this, some people say that could damage the board because of the lack of protection in the outputs.

On mine's now I have the decoupling capacitors changed by MKP 2.2uf (the ones before were 3.3uf although on the board is clearly printed 2.2, WTF??), and the sound improved a so much that I can't believe that.

Also have added another cap parallel on the power input, so now I have the 3300uf + 6800uf, and the power led doesn't blink like before.
  Reply With Quote
Old 7th December 2011, 10:52 AM   #994
Franfj is offline Franfj  Spain
diyAudio Member
 
Join Date: Dec 2011
Just one hint if anyone has the same problem as me, the amp started to make constant pops after changing caps. It doesn't enter in fault mode, just overload.

What happened is that the resin from the solder wire created some kind of conductor between some tracks. After a lot of time soldering and desoldering, with random success (some times pops on left channel, others on the right ) cleaning the pcb with alcohol solved the problem
  Reply With Quote
Old 12th December 2011, 03:18 AM   #995
pkozul is offline pkozul  Australia
diyAudio Member
 
Join Date: Feb 2011
Location: Melbourne, VIC
Default Toroidal inductors

Hi all,

Just saw these go up on eBay yesterday...

Coils sets for Tripath TA2020 20W Class-T Digital Audio Amp upgrade. | eBay

I asked the seller for the specs, and he replied with this info:

"Hello, this is 10uH, 5A. & very low resistant. We test all with other LCR Meter before ship."

Seems like it's worth a shot, eh? Cheapest toroid option I have seen so far.

Cheers,
Pete
  Reply With Quote
Old 12th December 2011, 06:56 AM   #996
diyAudio Member
 
Join Date: Jun 2009
Default another one !

Well I just bought these : http://www.ebay.ie/itm/260512722675?...9#ht_607wt_833 but i'm still waiting for post to arrive.
The ones you are looking should be fine. If you buy & test them just share your opinion with us.

Quote:
Originally Posted by pkozul View Post
Hi all,

Just saw these go up on eBay yesterday...

Coils sets for Tripath TA2020 20W Class-T Digital Audio Amp upgrade. | eBay

I asked the seller for the specs, and he replied with this info:

"Hello, this is 10uH, 5A. & very low resistant. We test all with other LCR Meter before ship."

Seems like it's worth a shot, eh? Cheapest toroid option I have seen so far.

Cheers,
Pete
  Reply With Quote
Old 14th December 2011, 03:52 PM   #997
diyAudio Member
 
Join Date: Aug 2011
I did the last mods on m lepai's lp2020a+. Looking at the output stage noticed that there is a smd cap just after the inductors. Well I have no clue what they intended to anchieve with that cap there but my guess is that it is their EMI output filter and they placed it right there before the output caps. Also the zobel cap on mine had one 0.47uF cap instead of 0.22uF. there we go:

Click the image to open in full size.

I used 10000pf 5% polystyrenes that I had around for C40 but you can use multilayer ceramics.
If you're going to use it as power amp you better replace R8 and R10 with 22k or 39K low noise resistor. Much better now .

On one of my units I did the bypass and added a volume pot following Pano mod for sonic impact. Great reading there.
If you want add the volume pot after you did the bypass on Lepai Lp2020A+ you should look at the image bellow.

Click the image to open in full size.
  Reply With Quote
Old 14th December 2011, 04:48 PM   #998
Franfj is offline Franfj  Spain
diyAudio Member
 
Join Date: Dec 2011
One doubt, which one will be better?

ALPS RK14
Click the image to open in full size.

ALPS RK27
Click the image to open in full size.

The first one is cheaper (about half the price of the second). Everybody uses the classical blue ALPS, but they both seem tho have the same specifications on the ALPS website, plus the first is smaller and looks like a newer model…
  Reply With Quote
Old 14th December 2011, 11:11 PM   #999
diyAudio Member
 
Join Date: Aug 2011
Quote:
Originally Posted by Franfj View Post
One doubt, which one will be better?

ALPS RK14
Click the image to open in full size.

ALPS RK27
Click the image to open in full size.

The first one is cheaper (about half the price of the second). Everybody uses the classical blue ALPS, but they both seem tho have the same specifications on the ALPS website, plus the first is smaller and looks like a newer model…
You can stick with the one that came with the lepai, it works just fine. Anyway if you think the lepai is worth of an alps pot you may get this one
  Reply With Quote
Old 15th December 2011, 01:17 AM   #1000
Franfj is offline Franfj  Spain
diyAudio Member
 
Join Date: Dec 2011
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?
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
New ta2020 pcb'S ArjenShenzhen Vendor's Bazaar 98 14th November 2012 12:39 PM
Ta2020 Bengali Class D 0 29th September 2007 06:28 AM
Eb-ta2020 opentop Class D 16 30th May 2005 08:42 AM


New To Site? Need Help?

All times are GMT. The time now is 02:26 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2