Lepai T-Amp with TA2020 - Page 136 - 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 14th December 2012, 11:10 AM   #1351
diyAudio Member
 
Join Date: Dec 2012
Quote:
Originally Posted by Bare View Post
DIY Audio is your friend:
Amplifier:Lepai T Amp - diyAudio


Thanks!
  Reply With Quote
Old 15th December 2012, 04:51 PM   #1352
diyAudio Member
 
Join Date: Aug 2008
Also, since the wiki and this thread are more about the older versions:
LP-2020A+ mod thread
__________________
Tyler
  Reply With Quote
Old 27th December 2012, 08:18 PM   #1353
diyAudio Member
 
Join Date: Feb 2012
Can someone please tell me if its possible to perform a "Power on pop suppressor" on the V2 board - LP-2020B.

The amount of movement on my speakers bass drivers and the loud pop on switch on in very concerning! I'm not to bothered about other mod's for now...I want to prevent damage to my vintage Wharfdale speakers by getting rid of the switch on thump.

Much obliged.
  Reply With Quote
Old 28th December 2012, 08:02 AM   #1354
diyAudio Member
 
Join Date: Dec 2012
that's a grate idia using capacitors.If it is ok with you can you give me the complete wiring diagram.I just had one of these amps, not yet used.It will be very helpful
  Reply With Quote
Old 14th January 2013, 06:23 AM   #1355
diyAudio Member
 
Join Date: Dec 2010
Quote:
Originally Posted by Fynn View Post
Yep. And if the gain is too low, you can adjust the gain with the 2 resistors after the decoupling-caps(c20/21) next to the TA2020 chip, according to the datasheet.
They were 15k and 20k for me, which sets the gain to: 12*20k/15k ->16x Vrms.
At 9Vrms you have 20W into 4 ohms / 10W into 8 ohms, which is about maximum for the ta2020. You reach that with 560mV.

I don't know how sensitive you can make the TA2020 though.


Hey I just did the tone and volume control bypass. Now the amp gain is too low when using my phone as an input certain videos and songs.
Does anyone have and suggestions what I should change these resistors to. Also a photo of which resistors I need to change would be awesome.
  Reply With Quote
Old 14th January 2013, 11:37 PM   #1356
diyAudio Member
 
Join Date: Sep 2012
Hey fellas,

I'll have a proper look through in the morning, but was there ever a fix for the imbalance issue? Mine is definitely outputting a lot more in the left channel than the right and it's really starting to annoy me. This is only a replacement while my PM66SE-KI is sick (almost conceding and taking it to a professional now) but i do quite like it and would like to fix it if it's quite a simple thing!
  Reply With Quote
Old 15th January 2013, 05:08 PM   #1357
Bare is offline Bare  Canada
diyAudio Member
 
Join Date: Dec 2001
Location: vancouver
Gain issues? Did you connect the new Film coupling caps.. Directly.. to the RCA input jacks ??
You Must :-)
  Reply With Quote
Old 16th January 2013, 02:32 AM   #1358
diyAudio Member
 
Join Date: Dec 2010
I did this mod Click the image to open in full size.
  Reply With Quote
Old 16th January 2013, 03:47 AM   #1359
diyAudio Member
 
Join Date: Aug 2011
If you want to correctly bypass and adjust the gain on your lepai then you need to connect directly to the RCA inputs instead of pads on R35 and R34 ( C31 and C 30 on pcb 120305 ) you should know that:

R8 and R10 and the Rin resistors while R9 and R11 are the Rfeed resistors. These are the resistors that adjust the gain. Look into the TA2020 datasheet to get the full explanation.

- For ipod and portable players with built in volume control use 22K for Rin and 39K for Rfeed

- If you want to play it safe with and set your lepai for general use you should use 22K for Rin and 22k for Rfeed.

- For signals coming from a pre-amplifier you can go for 56K for the Rin and 22K for the Rfeed

I will post an definitive mod list for the lepai in a few days . I just need the time to do it correctly with pictures and everything else.
I will also show how to make the "switch" button work as it should; bypassing tone controls for real.

[]'s
  Reply With Quote
Old 16th January 2013, 05:07 PM   #1360
Bare is offline Bare  Canada
diyAudio Member
 
Join Date: Dec 2001
Location: vancouver
Ahhh. No Ceegar :-) You've missed the target entirely
Trick is to copy the Wiki photo instruction ..Exactly.
Lose the crappy electrolytic caps you have stuck in there.. fit even very cheap film ones for unmistakeable improvement.
  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 11:39 AM
Ta2020 Bengali Class D 0 29th September 2007 05:28 AM
Eb-ta2020 opentop Class D 16 30th May 2005 07:42 AM


New To Site? Need Help?

All times are GMT. The time now is 05:41 AM.


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