Lepai T-Amp with TA2020 - Page 126 - 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 21st September 2012, 09:17 PM   #1251
Bare is offline Bare  Canada
diyAudio Member
 
Join Date: Dec 2001
Location: vancouver
Dunno..everything I've previously read suggested 13.5V was max.
Having already fried one Ta 2020 chip by accidentally shorting the speaker wires (tripped on them ) These chips don't suffer fools gladly :-)
I wouldn't risk it without solid evidence.
  Reply With Quote
Old 27th September 2012, 03:21 AM   #1252
chomdh is offline chomdh  United States
diyAudio Member
 
Join Date: Aug 2012
Has anyone rigged up a way to control this little guy with a remote or to add Bluetooth music streaming?

I have a slightly modded 2020a+ running two 6.5" two way Polk speakers in an igloo cooler and it is very portable yet sounds awesome.

I'm thinking about picking up one of the Logitech Bluetooth receiver boxes to stream audio from my iPhone to the lepai but was wondering if the receiver will run off the same sla battery.

Any tips or thoughts are appreciated.
  Reply With Quote
Old 5th October 2012, 02:23 AM   #1253
diyAudio Member
 
Join Date: Oct 2012
Quote:
Originally Posted by radiosmuck View Post
According to the ta2020 specs the absolute max supply voltage is 16 vdc.
I have just picked up a 16vdc 4amp wall wart switching ps, should I try it?
Thanks
you need to add four 40v 1A schottkey diodes in order for the amp to survive +13.5v. they're labeled as "Dh" on page five of the ta2020 datasheet.

i've done some mods myself to my amp. bypassed the opamp/tone/volume, changed the input caps to Nichicons, output inductors to Wurth and the output caps to Vishays. the biggest change is changing all output caps from 0.47uF to 0.22uF so the amp can drive 8ohm speakers easier (as per datasheet).

compared to the 0.47uF caps, the 0.22uF has _way_ better bass.



before
Click the image to open in full size.


after
Click the image to open in full size.

Last edited by dreamkiller323; 5th October 2012 at 02:51 AM.
  Reply With Quote
Old 7th October 2012, 03:06 AM   #1254
Bare is offline Bare  Canada
diyAudio Member
 
Join Date: Dec 2001
Location: vancouver
Nice.. Suggest fitting Film and foil input caps though. That! should please :-)
  Reply With Quote
Old 13th October 2012, 06:56 PM   #1255
Trileru is offline Trileru  Romania
diyAudio Member
 
Join Date: Dec 2010
Hi guys. I have a ta2020 amp made by Muse. Got it off ebay and modded it, replaced all caps on board, FM caps for psu, cheapest mundorf for input stage and some wima pp for output. I have 2 questions. First, is it good practice to bypass the input/output psu caps? I used 2 ero1837 for input caps only. Also can anyone recommend a (similar priced) DAC off ebay? I've seen Topping (about 100$) and Muse (about 40-50$). I don't know jack about DACs so any info is appreciated. I'm thinking of something similar (preferably Muse) to go with the same form factor as my t-amp. Also I'd get one and replace some components just because I like to fiddle. My worst aspect of diy are cases. I prefer to get a decent one than to make it/buy it myself as I don't have much time nor money I'm using either macbook pro/iphone/samsung tablet or sometimes a fast track pro as DAC. So if any of the cheaper DACs on ebay (with some work on replacing crappy parts) are a valid option please mention it. I think this would be good info for the rest of the guys that have a Lepai or any other ta2020 chip amp.
Thank you.
  Reply With Quote
Old 13th October 2012, 08:27 PM   #1256
diyAudio Member
 
Join Date: Mar 2011
Hi, Trileru!

You may try this one (HA-INFO U2 Plus):
HA INFO U2 Plus AD1852 Mini USB DAC + Headphone Amp + USB Converter 1pc | eBay
Review:
HA INFO U2 Plus USB DAC / Headphone Amp Review...the best inexpensive USB DAC headphone amp?

It sounds decent for me, may be best sound for this price + excellent TPA6120A headphone amplifier included. But I will recommend first of all get rid off decoupling capacitors and change PSU to a transformer-based, stabilized. Then try to change capacitors (in my case they was general purpose Elna RE3, changed to Nichicon KZ), also different opamp will sound better, I think (waiting for OPA2211). Best alternative for red Wima MKS2 can be NP0 SMD ceramic capacitors (0.1uf + 1000pf).

And please, don't buy MUSE for 40$. They are awful

Last edited by Insighter; 13th October 2012 at 08:36 PM.
  Reply With Quote
Old 13th October 2012, 08:51 PM   #1257
Trileru is offline Trileru  Romania
diyAudio Member
 
Join Date: Dec 2010
Quote:
Originally Posted by Insighter View Post
Hi, Trileru!

You may try this one (HA-INFO U2 Plus):
HA INFO U2 Plus AD1852 Mini USB DAC + Headphone Amp + USB Converter 1pc | eBay
Review:
HA INFO U2 Plus USB DAC / Headphone Amp Review...the best inexpensive USB DAC headphone amp?

It sounds decent for me, may be best sound for this price + excellent TPA6120A headphone amplifier included. But I will recommend first of all get rid off decoupling capacitors and change PSU to a transformer-based, stabilized. Then try to change capacitors (in my case they was general purpose Elna RE3, changed to Nichicon KZ), also different opamp will sound better, I think (waiting for OPA2211). Best alternative for red Wima MKS2 can be NP0 SMD ceramic capacitors (0.1uf + 1000pf).

And please, don't buy MUSE for 40$. They are awful
I may build a transformer based psu but the one that I have (S-40-12 - 42W 12V 3.5A Enclosed Switchmode Power Supply) is dead quiet and delivers as much as I need, and adjusted for 13.5V (I'm using 8ohm speakers so I need about 2A max).
Then I don't know if removing the input caps is safe plus that the cap coloration might be actually nice. I replaced all caps, none is smd. I installed wima PP where possible. My amp does not have any opamp (I'll use a tube preamp at some time).
After looking at everything I decided that Muse is the best bang for the buck. Very nice case, good pot and nice connectors. Board is double layer and looks real neat. Since I replaced all caps anyway I just wanted cheapest amp with a nice case. Also I replaced the inductors with the one from 41hz.com designed for amp6 kit (and are actually the ones that Tripath chip datasheet recommends to be used).
So now I need a DAC and preamp that fits the same form factor. I'd build a PSU in the same style at some point if I can find a case that looks similar to everything else.
Thanks for the tip, I'll read on your DAC.
  Reply With Quote
Old 13th October 2012, 09:14 PM   #1258
diyAudio Member
 
Join Date: Mar 2011
All that I wrote in previous post was about HA-INFO DAC, not about MUSE amps.
Most of this amps not bad at all. Slightly worse than Topping, and even SMSL, but not bad. MUSE DACs usually using simple PCM2xxx chips, which not Hi-Fi. May be sound pleasant and warm for some guys, but definitely not Hi-Fi.

Of course, you can use good switch power supply for DAC, they can be very nice too.

Forgot to say about GrubDAC. It's very basic DIY DAC, with interesting sound, I have one. Also best for it's price. Far better than PCM2xxx.

http://www.diyforums.org/GrubDAC/
http://www.head-fi.org/t/445155/the-grubdac
http://beezar.com/catalog/index.php?cPath=40

If you interested - I can sell you mine.

Good luck!

Last edited by Insighter; 13th October 2012 at 09:29 PM.
  Reply With Quote
Old 24th October 2012, 11:17 PM   #1259
diyAudio Member
 
Join Date: Jun 2008
Hi - new to t-amps. Bought the Lepai 2020 Mk1 model with no tone defeat and I have been blown away by the sound. I've done the following mods but have a question:

12V 6A PSU

Replaced power inductor with wire.

Tone Bypass

All good except the tone bypass has brought a little grain to the top end that was previously silky smooth and a softer bass. Clarity is amazing though.

I have only connected wires from the resistors to the caps, not changed the components themselves yet. The instructions which I found in this thread say replace with 22k resistors and 2,2-4,7uf caps.

What do these changes do, and will it return the silky top end?

s
  Reply With Quote
Old 25th October 2012, 02:30 AM   #1260
Bare is offline Bare  Canada
diyAudio Member
 
Join Date: Dec 2001
Location: vancouver
Concidentally I was just this afternoon fooling with my Last Lepai... been sitting in it's shipping wrappings for weeks.
Look in the Lepai Wiki here and DO the tone bypass.. in it's entirety.
IMO It's mandatory for decent sound
You will then have 1.8 /2.2 UF input caps, metal film types, straight from input RCA's to the disconnected from the PCB Volume pot and then to the inputs on the board where C20, C21 were.
Presumably you have fitted decent inductors? AND fitted decent output caps of 0.22/ 0.47uf (dependent on your Speaker ohms? It's necessary.
Then you should have a 'as good as a Lepai can be' result.
Frankly I've found by accident that the Yuang Jin ta2020 Amp is erm.. Better sounding than My modified Lepai (latest version..red PCB) Right out of the shipping wrappings!. Cheap too at $14 ebay .. Buy one, it won't be a dissapointment :-)
This thing has DC current adjust, a full fitment of Wima caps and decent quality inductors. No mods actually needed.. although I did 'upgrade' the PS cap.
G'luck
  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 01:17 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