Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Digital Line Level DACs, Digital Crossovers, Equalizers, etc.

DIYINHK AK4497 DAC Mods
DIYINHK AK4497 DAC Mods
DIYINHK AK4497 DAC Mods 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 19th November 2019, 04:23 PM   #1
chinook9 is offline chinook9  United States
diyAudio Member
 
Join Date: Aug 2013
Default DIYINHK AK4497 DAC Mods

I have a DIYINHK AK4497 DAC. There are a couple of relatively easy modifications that can be made.

The DIYINHK website states:
The PCB is designed to be DIY friendly.

Diyer can cut the trace and uses the socket labelled AVDD_R(5.0V) for the supply the right channel analog power supply individually.

Remove FB1 and useDVDD(3.3V) for optional individual digial power supply.


In your judgement, is it likely that these modifications will improve the sound of the DAC? Also, which trace would be cut and where?
Attached Images
File Type: jpg AK4497 board.jpg (270.7 KB, 405 views)
File Type: jpg AK4497 board-1.jpg (142.0 KB, 410 views)
  Reply With Quote
Old 20th November 2019, 09:42 PM   #2
chinook9 is offline chinook9  United States
diyAudio Member
 
Join Date: Aug 2013
No one can help me with this?
  Reply With Quote
Old 20th November 2019, 10:42 PM   #3
Markw4 is offline Markw4  United States
diyAudio Member
 
Join Date: Jul 2016
Location: California
Looks like the AVDD follows the trace colored red in the pdf file below below. The green trace goes to another power connector so it would presumably need to be cut somewhere before it meets the red trace.

As to whether or not it should be separately powered, you would have to try it and see if any difference in sound quality. If you don't believe there is any benefit you could always solder the cut trace back together and use a single power supply.

That said, you should probably use a really good USB board for testing since jitter there will also affect sound quality. Also use a good amp and speakers. In other words, if any part of your system is not up to par its possible there would be an improvement from separate power, but your system might not be working good enough to make the power supply difference easy to hear.

Additional Comments:
The left/right channel analog reference voltages appear to be VREFHL and VREFHR. If interested you might take a look at how AKM powers them on the AK4497 evaluation board, which can be found at: https://www.akm.com/content/dam/docu...tionmanual.pdf ...schematic is on page 39. Looks much like a Jung type of regulator and very similar to what is used for each L/R channel on AK4499 evaluation board. The regulators sound good for analog audio which is probably why they use them. Probably better not to use an LDO for that.

Regarding USB boards, I found JLSounds I2SoverUSB to sound like it had lower jitter than a diyinhk USB board. Both USB boards use the same clocks it looked like, but there would seem to be other implementation differences that affect performance.
Attached Files
File Type: pdf AK4497BoardMod.pdf (35.1 KB, 63 views)

Last edited by Markw4; 20th November 2019 at 11:01 PM.
  Reply With Quote
Old 21st November 2019, 02:36 AM   #4
chinook9 is offline chinook9  United States
diyAudio Member
 
Join Date: Aug 2013
Thank you Mark! That's more than i hoped for.

I had checked out the JLSounds board. I imagine I could figure out how to install it, however, I'm not sure about the need for drivers (if any) when playing from Android.

I've pretty much moved over playing FLAC files or streaming the best quality from TIDAL. I do not use any DSD.
  Reply With Quote
Old 21st November 2019, 06:47 AM   #5
nautibuoy is offline nautibuoy  United Kingdom
diyAudio Member
 
nautibuoy's Avatar
 
Join Date: Jan 2010
Location: Somerset, England
Recommendation for the JLSounds USB board seconded; they work really well and are excellent value for money.

I use my Samsung Android phone to hook up to a JLSounds USB board. You just need a USB OTG interface cable and it just works.

If you've not come across it I recommend looking at the 'USB Audio Player Pro' app for your Android device - it is a superb music playing app optimised for Android platforms, bypassing the less optimal standard Android playback constraints. Using it on my phone I am able to 'play' hi-res FLAC files either locally on my phone or, better still, out to the JLSounds board to be decoded by a decent DAC - far superior to MP3 listening.

USB Audio Player PRO
  Reply With Quote
Old 22nd November 2019, 05:21 AM   #6
chinook9 is offline chinook9  United States
diyAudio Member
 
Join Date: Aug 2013
Thank you for the recommendation nautibuoy. I wasn't aware of the changes that have been made to UAPP.

I will be heading to my winter residence (AZ) this weekend and will try it as soon as I'm unpacked. I expect I'll also order a JLSounds I2SoverUSB. I may also mod the DIYINHK DAC as described by MarkW4 if I feel comfident I won't mess up cutting the trace.
  Reply With Quote
Old 26th November 2019, 06:40 PM   #7
laserscrape is online now laserscrape
diyAudio Member
 
Join Date: Dec 2017
Quote:
Originally Posted by Markw4 View Post
If interested you might take a look at how AKM powers them on the AK4497 evaluation board, which can be found at: https://www.akm.com/content/dam/docu...tionmanual.pdf
That evaluation board datasheet actually looks like it delves into the how-to of programming the chips unlike the actual DAC chip datasheets, first time ive seen that. The Ak4499 doesnt have anything like that (yet)... I thought full training in digital programming was just expected for anyone using the chips.
  Reply With Quote
Old 26th November 2019, 07:06 PM   #8
laserscrape is online now laserscrape
diyAudio Member
 
Join Date: Dec 2017
Not really a mod but If you are using headphones you could try enabling HLOAD pin (rated to drive loads down to 120ohm) and driving headphones directly from DAC chip outputs ... was always curious what that might sound like.

Also try playing around with filter modes. AKM's super slow filter is supposed to be like NOS , DIYinHK actually posted measurements here showing perfect square wave output from Ak4497 with this filter.
My favourite was the slow roll-off filter, the default short delay sharp rolloff sounded pretty poor.

See in page 61 in the datasheet for configurations of the filter pins (SD,SLOW and SSLOW),
DIYinHK has provided jumper pads for all the pins which are labeled on the underside on the board.

Last edited by laserscrape; 26th November 2019 at 07:09 PM.
  Reply With Quote
Old 26th November 2019, 07:11 PM   #9
randytsuch is offline randytsuch
diyAudio Member
 
Join Date: Jan 2003
Location: LA
DIYINHK AK4497 DAC Mods
Quote:
Originally Posted by chinook9 View Post
Thank you for the recommendation nautibuoy. I wasn't aware of the changes that have been made to UAPP.

I will be heading to my winter residence (AZ) this weekend and will try it as soon as I'm unpacked. I expect I'll also order a JLSounds I2SoverUSB. I may also mod the DIYINHK DAC as described by MarkW4 if I feel comfident I won't mess up cutting the trace.
Do you have a scrap PWB to practice on? Every PWB will be a little different, some harder and some easier, but still its worth trying on something you don't care about first.
I use a very sharp exacto knife, and ohm it out. Sometimes it looks cut but really isn't.
__________________
My system is here
http://randytsuch-audio.blogspot.com/2005/10/my-system.html
  Reply With Quote
Old 3rd December 2019, 04:16 PM   #10
chinook9 is offline chinook9  United States
diyAudio Member
 
Join Date: Aug 2013
Quote:
Originally Posted by laserscrape View Post
Not really a mod but If you are using headphones you could try enabling HLOAD pin (rated to drive loads down to 120ohm) and driving headphones directly from DAC chip outputs ... was always curious what that might sound like.

Also try playing around with filter modes. AKM's super slow filter is supposed to be like NOS , DIYinHK actually posted measurements here showing perfect square wave output from Ak4497 with this filter.
My favourite was the slow roll-off filter, the default short delay sharp rolloff sounded pretty poor.

See in page 61 in the datasheet for configurations of the filter pins (SD,SLOW and SSLOW),
DIYinHK has provided jumper pads for all the pins which are labeled on the underside on the board.
Just getting back to this after settling into the AZ house.

I feel pretty comfortable cutting the trace, but before I do that, I'd like to try and change the filters.

I can see how the SD, SLOW, and SSLOW are marked on the underside of the PCB. I assume I can use jumpers to change the filter but its not clear how.

Could anyone please help me with this?
  Reply With Quote

Reply


DIYINHK AK4497 DAC ModsHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
AK4497 won't be Flagship anymore foo Digital Source 80 5th October 2019 07:03 AM
AK4497: default oversampling??? chinook9 Digital Line Level 6 22nd March 2019 04:09 PM
FS: AKM AK4497 TzeYang Swap Meet 0 20th December 2018 06:14 AM
Dual AK4497 DAC Project nautibuoy Swap Meet 2 26th June 2017 09:22 AM
ES9038PRO VS AK4497 FIR Filter diyinhk Digital Source 8 4th November 2016 01:39 AM


New To Site? Need Help?

All times are GMT. The time now is 11:35 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki