Go Back   Home > Forums > >

Class D Switching Power Amplifiers and Power D/A conversion

Sabaj A20a modification... worth the effort?
Sabaj A20a modification... worth the effort?
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
Old 15th September 2021, 05:47 AM   #1
jean-paul is offline jean-paul  Netherlands
diyAudio Moderator Emeritus
 
jean-paul's Avatar
 
Join Date: Sep 2002
Location: Germany
Default Sabaj A20a modification... worth the effort?

This little MA12070 "Merus" based amplifier that could... Can it be modified? Does it need to be modified? And what do we do to the poor creature then? Nah, we just do it like we always do

Post your modifications please and tell us:

1. what the improvement or the "improvement" was

2. what gave you the idea?

3. was it worth the effort?

Preferably with pictures in a reasonable resolution and a clear description what part/type numbers you have used. Avoid "blacker than black" to avoid the curse of the burned woofer that may come upon you!
__________________
It's only audio. Member of the non modular PCB design committee.

Last edited by jean-paul; 15th September 2021 at 06:02 AM.
  Reply With Quote
Old 16th September 2021, 12:55 PM   #2
dubai2000 is offline dubai2000  Europe
diyAudio Member
 
Join Date: Apr 2008
I have alraeyd mentioned it in another thread, but in case somebody else stumbles upon this thread: Not a modification, but turning up the input voltage (easy to do as the PS board can be unscrewed without removing any ribbon cables) makes the amp simply play more "grown up" - i.e. you get more of everything: timbres, soundstage, dynamics.
  Reply With Quote
Old 16th September 2021, 01:01 PM   #3
jean-paul is offline jean-paul  Netherlands
diyAudio Moderator Emeritus
 
jean-paul's Avatar
 
Join Date: Sep 2002
Location: Germany
The would be the output voltage I presume? Please a picture and the value. What voltage exactly?
__________________
It's only audio. Member of the non modular PCB design committee.
  Reply With Quote
Old 16th September 2021, 07:48 PM   #4
dubai2000 is offline dubai2000  Europe
diyAudio Member
 
Join Date: Apr 2008
Sorry, I did not take a picture, but once you remove the PS board the tiny adjustment pot can be easily spotted - I just turned it to max as the power supply does offer just under 26V as maximum - hence just below the limit of the chip - and yes - output voltage of the PS.
  Reply With Quote
Old Yesterday, 01:07 AM   #5
UAN is offline UAN  Ukraine
diyAudio Member
 
Join Date: Feb 2020
Yes, for the MA12070 chip, the supply voltage is no more than 26 V. In general, these chips are intended for portable, portable equipment. But Chinese friends use them in stationary equipment.
  Reply With Quote
Old Today, 07:36 AM   #6
jean-paul is offline jean-paul  Netherlands
diyAudio Moderator Emeritus
 
jean-paul's Avatar
 
Join Date: Sep 2002
Location: Germany
The German producer of the MA12070 states the following:

Description Features

The MA12070 is a super-efficient audio power amplifier based on proprietary multi-level switching technology. It supports a 4-26V supply voltage range, allowing it to be used in many different applications. Multi-level switching enables very low power loss during operation. In addition, it allows the amplifier to be used in filterless configurations at full rated power in a wide range of audio products.

"intended for portable" can not even be found. You are posting fake news, sorry.
__________________
It's only audio. Member of the non modular PCB design committee.

Last edited by jean-paul; Today at 07:39 AM.
  Reply With Quote
Old Today, 09:13 AM   #7
UAN is offline UAN  Ukraine
diyAudio Member
 
Join Date: Feb 2020
"Supply voltage 4 ... 26V" and high efficiency speaks about the field of application of these chips. The absence of output filters is a bonus of this technology and
significantly improves sound quality.
I have amplifiers A30 and TPA3255, both sound almost the same. Bass is better on TPA - more damping coefficient of acoustics. Therefore, a MA12070 chip is installed on each channel.
But the power is small compared to TPA3255.
  Reply With Quote
Old Today, 02:37 PM   #8
dubai2000 is offline dubai2000  Europe
diyAudio Member
 
Join Date: Apr 2008
Yes, less power but (to my ears!) better sound.....
  Reply With Quote
Old Today, 03:05 PM   #9
UAN is offline UAN  Ukraine
diyAudio Member
 
Join Date: Feb 2020
I also like the sound of MA12070 more. Probably due to the lack of filters.
  Reply With Quote
Old Today, 06:40 PM   #10
zek is offline zek
diyAudio Member
 
zek's Avatar
 
Join Date: Aug 2003
Has anyone listened to and compared the A20a and the little brother A10a?
  Reply to this post

Reply


Sabaj A20a modification... worth the effort?Hide this!Advertise here!
Thread Tools

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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Sabaj D3 Asio tony.garner Digital Line Level 2 23rd July 2020 06:19 PM
Sabaj DA3 Dual ES9018Q2M DAC Internal Pics wushuliu Digital Line Level 3 30th October 2017 11:50 PM
Is it worth the effort? reticent67 Car Audio 10 6th July 2004 04:53 AM
Is this mod worth the effort? clevegilbert Tubes / Valves 2 27th January 2004 01:23 PM
"Angling rings"... worth the effort? eRiCdWoNg Multi-Way 16 4th August 2003 09:50 PM


New To Site? Need Help?

All times are GMT. The time now is 07:48 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Copyright ©1999-2021 diyAudio
Wiki