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

PC Based Computer music servers, crossovers, and equalization

IanCanada's Latest RPi GB Goodies Impressions... and your tweaks, mods and hints...
IanCanada's Latest RPi GB Goodies Impressions... and your tweaks, mods and hints...
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 13th May 2019, 09:27 PM   #351
randytsuch is offline randytsuch
diyAudio Member
 
Join Date: Jan 2003
Location: LA
Quote:
Originally Posted by Markw4 View Post
Thought it best to reply separately on the above issue.

I have been using Arduino as an I2C bus controller for awhile now (for various types of chips, including ES9038Q2M). What would be helpful to know is where everyone else is at on that subject. In other words, do I have to do all the work? How much explaining would be needed? Those kinds of things.

Also, it may help to know I tend to use pretty minimalist code for my experiments. I haven't been designing a complete diy project ala Dimdim. Don't like programming enough for that. It means people have to be willing to learn about low level register programming if doing things my way. I am always happy to answer technical questions and explain what I can.

Of course, maybe Ian will have a solution and things will kind of take care of themselves.
I have written Arduino programs in the past, but I have a HW background so am a pretty brute force type programmer.

But after spending a little time looking into what's out there, seems like using Dim dim's hifiduino code and setup may be the best option.

Don't want to reinvent the wheel if I don't need to.
__________________
My system is here
http://randytsuch-audio.blogspot.com/2005/10/my-system.html
  Reply With Quote
Old 13th May 2019, 11:47 PM   #352
Markw4 is offline Markw4  United States
diyAudio Member
 
Join Date: Jul 2016
Location: California
Quote:
Originally Posted by randytsuch View Post
...after spending a little time looking into what's out there, seems like using Dim dim's hifiduino code and setup may be the best option.
Would someone out there be willing to try it?
  Reply With Quote
Old 14th May 2019, 02:45 PM   #353
randytsuch is offline randytsuch
diyAudio Member
 
Join Date: Jan 2003
Location: LA
Quote:
Originally Posted by Markw4 View Post
Would someone out there be willing to try it?
I'm probably 2-3 months before I have anything running.
And be a while before I decide for sure what I want to do for controlling the dac.


Here is a url to dimdim's project.
TFT HiFiDuino Pro Project | Dimdim's Blog

Looked a little more at it.
The easiest way would be to buy the adapter board he sells to add the Arduino peripherals required. I've hardwired Arduino projects by hand in the past, but its a pain.

And you need to wire a led lock signal to gpio4. The dual mono dac has two lock leds. I'd pick one to use, and figure they should be in the same state. Otherwise need to add an and gate to make sure both dacs are locked.

Way harder than just plugging in Ian's controller, but seems to give you full control of the registers. And you have the source code so changes/additions/customizing is possible.

Other advantage is no need to worry about contention on the i2s bus if you add a processor to it, but I don't know if this is a real concern or not.

Randy
__________________
My system is here
http://randytsuch-audio.blogspot.com/2005/10/my-system.html
  Reply With Quote
Old 14th May 2019, 03:33 PM   #354
Markw4 is offline Markw4  United States
diyAudio Member
 
Join Date: Jul 2016
Location: California
Quote:
Originally Posted by randytsuch View Post
And you need to wire a led lock signal to gpio4.
Why is that? Lock status can be read from a dac register and or a dac chip GPIO pin can be programmed via I2C bus to act as a lock status indicator output. Either way, some I2C controller activity would be needed to make lock status knowable.
  Reply With Quote
Old 14th May 2019, 06:06 PM   #355
randytsuch is offline randytsuch
diyAudio Member
 
Join Date: Jan 2003
Location: LA
Quote:
Originally Posted by Markw4 View Post
Why is that? Lock status can be read from a dac register and or a dac chip GPIO pin can be programmed via I2C bus to act as a lock status indicator output. Either way, some I2C controller activity would be needed to make lock status knowable.
Copied from Dimdim's blog
The GPIO4 line is very handy to have, since it provides feedback to the controller whenever a lock/unlock condition happens or when the sampling rate changes, but the code could be adapted to work without it (like the original (TFT) HiFiDUINO code did, polling the DAC every couple of seconds to see if anything has changed).

So you can poll, but the code as running now looks at the gpio to determine lock status.

or add a wire from a lock led to the gpio pin and run the code as is.
__________________
My system is here
http://randytsuch-audio.blogspot.com/2005/10/my-system.html
  Reply With Quote
Old 14th May 2019, 08:56 PM   #356
sq225917 is offline sq225917  United Kingdom
diyAudio Member
 
Join Date: Jun 2004
Location: sheffield
Send a message via MSN to sq225917 IanCanada's Latest RPi GB Goodies Impressions... and your tweaks, mods and hints...
Fitted OPA1612 tonight, that's much better a big improvement. Definitely heading in the right direction now. Clocks and supercaps next.
__________________
Paradise Pre-reg PSU PCBs
  Reply With Quote
Old 15th May 2019, 04:15 PM   #357
Markw4 is offline Markw4  United States
diyAudio Member
 
Join Date: Jul 2016
Location: California
Quote:
Originally Posted by Markw4 View Post
Just tried the Crystek 957 clocks instead of NDK. Sounds closer to right to me, although still some remaining sound quality problems.

Cleaning up remaining distortion should help a lot. Now it sounds more like IMD rather than jitter, as the bigger problem. The sound seems a bit muffled and jumbled together in the midrange which sounds like a lot of HD/IMD contributing to that. But adding artificial brightness and pseudo-clarity from NDK jitter is not the fix, it just adds another problem.

Harmonic distortion compensation should probably be the next thing to look at. If an FFT shows much in the way of higher than 3rd harmonic, then some hardware troubleshooting would be necessary.

To summarize configuration so far:
*DVCC on ADM7150
*VCCA on ADM7150
*AVCC on NewClassD UWB2 (with 5.7v regulator powering dac board)
*Output stage +-15v using parallel film caps from each rail to ground (10+10+33+33+33, all values uf, Wima mks4)
*Output stage on ribbon extender to help attenuate RF leakage into output stage
*Crystek 957 clocks, rather than NDK.

Note: Still on my to-do list:
*Test ADM7150 with a 33-ohm 1/2-watt resistor to ground to see if that makes it more usable for AVCC (or otherwise improves SQ elsewhere).
*Try adding C9, C10 to output stage board (NPO or C0G).

Also, checked I2S signals on clean 40-pin GPIO bus. Don't know why termination resistors would be needed. Pic of BCLK below.
To follow up a bit on my previous post above: Tried both ADM7150 and UWB2 regulators with 33-ohm load resistors for AVCC. Both sound better that way, or maybe the AVCC circuitry inside the dac likes the 33-ohm resistor there. Either way, it helps improve sound quality.

UWB2 sounds a little softer on the transients than ADM7150, but it also seems a bit more forgiving of distortion (all dac board regulators still supplied with 5.7v in order to bias on UWB2, but not exceed board filter cap voltage rating).

For the next test, I separated the AVCC regulator from dac board 5.7v supply and connected that one regulator to a variable supply. Didn't want to get the regulators too hot since they were both supplying 100ma to the 33-ohm resistors mounted on them, so avoided raising the input voltage very much. Found that both regulators sounded better and SQ was less distorted with regulator input voltage increased to 6.7v. With the input voltage increased, ADM7150 turned out to produce the best SQ, it was both tight and punchy as it should be for the music that was playing, and it also provided for the lowest distortion I have heard so far out of the dac.

I really think its time for harmonic distortion compensation at this point. The dac is getting much closer to producing acceptable SQ for my testing purposes. Depending on how much HD comp. can help, it may be okay to leave the output stage as-is (on the extender cable). Otherwise, the output stage will be the next thing to get attention.
Attached Images
File Type: jpg IanDac2b.jpg (953.9 KB, 189 views)

Last edited by Markw4; 15th May 2019 at 04:32 PM.
  Reply With Quote
Old 15th May 2019, 05:27 PM   #358
DUC985 is offline DUC985  Germany
diyAudio Member
 
Join Date: Oct 2004
Location: NRW
Today i installed the OPA1612, this is probably having the biggest impact, so before start modding plug them in first.

I have now fitted the :
- NDK Clocks like them better than Crystek
- Added a supercap on the DAC board supply 0.33F
- AVVC bypassed with a Sanyo Oscon
- Added to Elma Slimic to the +- Supply Lines of the Output board
- Replaced Opamps with OPA1612

I am quite happy with the sound now need more time to compare it to my other gear ...
  Reply With Quote
Old 15th May 2019, 05:37 PM   #359
Markw4 is offline Markw4  United States
diyAudio Member
 
Join Date: Jul 2016
Location: California
Quote:
Originally Posted by DUC985 View Post
Replaced Opamps with OPA1612
The was the first thing I did, too. Forgot to mention it my configuration summary a couple of posts above. The Brown Dog dip adapters can be seen in the pic
  Reply With Quote
Old 15th May 2019, 05:45 PM   #360
DUC985 is offline DUC985  Germany
diyAudio Member
 
Join Date: Oct 2004
Location: NRW
i did them last which was not the right thing to do
  Reply With Quote

Reply


IanCanada's Latest RPi GB Goodies Impressions... and your tweaks, mods and hints...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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Detailed specifics, hints and tweaks in designing a sealed sub Squeak Subwoofers 1 17th July 2015 03:27 PM
The latest tweaks :) lowtherdream Everything Else 6 13th January 2009 05:43 PM
S5 K-16LS mods, tweaks? hartze11 Tubes / Valves 3 1st December 2008 05:13 AM
NAD C541i: possible tweaks and mods? Karlosak Digital Source 4 23rd November 2006 06:20 PM
Any mods/tweaks for a Panasonic DVD S-49 mikee55 Digital Source 4 19th March 2006 07:04 AM


New To Site? Need Help?

All times are GMT. The time now is 10:58 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki