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.

ES9038Q2M Board
ES9038Q2M Board
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 20th June 2018, 12:05 AM   #1531
babolcs is offline babolcs  Hungary
diyAudio Member
 
Join Date: Dec 2011
Quote:
Originally Posted by freezebox View Post



Babolcs,
the circuit in the post 1294 is what I finally use. It automatically sets the DAC into current mode. Nothing else to do to achieve that.. The left part of the circuit is on the bottom side on a seperate board while the right part was applied on the top side by modifying the existing circuit (replacing all components). What you dont see on the pictures are the vertical 6K8 resistors where the outputs of bottom board are connected to the circuit on the top side..Also be aware of the exact polarity of the opamp inputs. Pls ask if you have any further questions.

Hi Freezebox, All

I have done the I/V stage. Although not 100% copy of your circuit. Since I'm lazy I used the LP filter stage which was on the panel, and added the I/V stage according you schematics. Thanks it works fine.
In the I/V stage I used the LME49720. and since I didn't have at home more I used in the LP filter stage OPA2134 - will be change to LME49720 too.
(some advices can be found here also: https://www.by-rutgers.nl/IV-converter.html)



So the current status summary of all MODs I've done:
1) I/V stage

as described above


2) AVCC_L,R

I powered them with an OPA based solution. Described here OPA based Ultra Low noise VREF for DAC more detailed in post 70.

3) Power supplies

- All the panel's power supply is separated with LP5907 and this is powered with a LM317+TL431 modul
- the controller remained on the 7805 (separated)
This 2 were described in this thread in the post 1306

- The I/V stage with the LP filter and the AVCC OPA based REF are powered from a SALAS shunts v1.3

4) CAPs
- I changed the important power CAPs to Nichicon MUSE types.

5) Upsample
- I ordered the upconversion unit, suggested by Mark based on the SRC4392
(this not yet arrived yet)


I do not intend to replace the clock - according some posts here it can further enhance the voice, but maybe not too much comparing with the above described MODs.

So thanks again for your inspirations and helps. Since I'm satisfied with the voice I really stop here the moddings on this panel. I will try to find a box and will put my ugly panel into it. :-).

See some more pictures. Not nice, but sounds OK.

babolcs
Attached Images
File Type: jpg IMG_1294.JPG (925.6 KB, 266 views)
File Type: jpg IMG_1295.JPG (896.5 KB, 255 views)
File Type: jpg IMG_1296.JPG (915.6 KB, 230 views)
  Reply With Quote
Old 20th June 2018, 01:16 AM   #1532
keilau is offline keilau  United States
diyAudio Member
 
Join Date: Mar 2013
Location: Windy City, US
Quote:
Originally Posted by Markw4 View Post
Well, I couldn't resist, so one is on order. For my next project I think I will go through one of the new DAC boards and see what I find that needs modding. I will let you know more when it gets here and I can take a good, close look at it.
Do you get a delivery date estimate yet? If it improvs SQ over the one you are doing the mod with its I/V output, I definitely want to order one.
  Reply With Quote
Old 20th June 2018, 03:04 AM   #1533
Markw4 is offline Markw4  United States
diyAudio Member
 
Join Date: Jul 2016
Location: California
Quote:
Originally Posted by keilau View Post
Do you get a delivery date estimate yet?
Not yet. It's one of those things where they set the status to shipped, then it sits there saying 'awaiting pickup.' Sometimes that can go on for a couple of weeks before it starts to move. You know.

I doubt the new board is going to be better than my modded board in the beginning. (The modded board already has an IV output.) The question is probably more like how much work would it take to get it there. Hopefully, it will take a lot less work than the first on did. But who knows, we will just have to wait as see.
  Reply With Quote
Old 20th June 2018, 03:26 AM   #1534
keilau is offline keilau  United States
diyAudio Member
 
Join Date: Mar 2013
Location: Windy City, US
Quote:
Originally Posted by Markw4 View Post
Not yet. It's one of those things where they set the status to shipped, then it sits there saying 'awaiting pickup.' Sometimes that can go on for a couple of weeks before it starts to move. You know.

I doubt the new board is going to be better than my modded board in the beginning. (The modded board already has an IV output.) The question is probably more like how much work would it take to get it there. Hopefully, it will take a lot less work than the first on did. But who knows, we will just have to wait as see.
In fact, I fully expect the new board to be less than your mod. I want to know if it has SQ improvement over the unmodded old board. If yes, how would you quantify that?

The I/V mod is doable. But the clock mod is another level.
  Reply With Quote
Old 20th June 2018, 04:48 AM   #1535
Markw4 is offline Markw4  United States
diyAudio Member
 
Join Date: Jul 2016
Location: California
Don't know about the clock mod being on another level. Could be there are easier ways and harder ways to do it. The way I did it was probably more towards the harder side. But soldering 4 little wires to the four pads and then soldering a clock a positioned a little bit above the board to the 4 wires should fairly easy. Vibration could be a concern if being held only by wires, but once it is working one could maybe put a dab of hot melt glue, or of electronics silicone adhesive between it and the board to hold it in place and keep it from moving around.

Note: Important to be aware that electronics silicone adhesive is not the same stuff as is usually found in the local hardware store glue section, but it is probably possible to find it at Amazon or one of the electronics suppliers such as Mouser or Digikey.

Regarding quantifying the new board, maybe there will be an opportunity to take some measurements. Obviously, I could compare it to DAC-3 and give a subjective assessment. Another way of looking would be to wait and see how many mods I end up doing on it until I am happy with the SQ. In a way that might be the most telling at least to some people who might be interested to know what they could be in for if they want to make it better.

Last edited by Markw4; 20th June 2018 at 04:55 AM.
  Reply With Quote
Old 20th June 2018, 04:12 PM   #1536
Markw4 is offline Markw4  United States
diyAudio Member
 
Join Date: Jul 2016
Location: California
As a part of some testing with all the various DAC boards and digital audio connection options available I was going to try running all the 5v supplies from one 5v power supply. Had an LT3042 board that was no doubt overkill but should work at least to do some testing.

Turns out it didn't work with the AK4137 SRC board which hung at boot when powered from the LT3042 board. Turns out the 5v was coming up too slow for the SRC board microcontroller to boot properly. Needed to do something to get it working so decided to try modding the LT3042 board for fast-start operation.

That requires connecting 2 resistors to pin 6, which was found to be connected to pins 1 and 2 by a trace running under the chip. No easy way to get at the trace so decided to try lifting pin 6. First removed big filter cap on board to create better access to the chip. Must have tried a little too hard when lifting the pin with an Exacto knife because it popped up rather suddenly and pin 7 loosened slightly. Have to be more gentle next time. Anyway, re-soldered pin 7 and connected 2 resistors to pin 6. Fast start now works very quickly, and AK4137 board boots right up with no problems. Pics below.
Attached Images
File Type: jpg LT3042 Fast Start mod.jpg (271.2 KB, 184 views)
File Type: jpg LT3042 Lift.jpg (748.3 KB, 183 views)
File Type: jpg LT3042 Soldered.jpg (713.2 KB, 70 views)

Last edited by Markw4; 20th June 2018 at 04:15 PM.
  Reply With Quote
Old 20th June 2018, 04:29 PM   #1537
Mikett is offline Mikett  Canada
diyAudio Member
 
Join Date: Aug 2003
Location: Toronto
Mark it would have been a good test to use that LT3042 against the OP amp AVCC to determine what the differences were both aural and measured. Why not? I am sure many would be very interested.
  Reply With Quote
Old 20th June 2018, 04:41 PM   #1538
Markw4 is offline Markw4  United States
diyAudio Member
 
Join Date: Jul 2016
Location: California
The LT3042 as configured is for 5v, not 3.3v. Also, 1.5A or whatever amps seems like even more overkill to use for AVCC when it comes to an ES9038Q2M.

I do have a way I am working on to try LT3045 for AVCC, but I need to get 22uf Cset caps first. Not sure what caps I want to use for that, haven't even got that far. Also have some LiFePO4 batteries around here I could try. In addition, I have AD797 opamps to try. However, before butchering up my DAC board with probably unnecessary AVCC options, there are some other things I would like to do first.

Say, since you have a PRO board now have you measured AVCC current draw at various sample rates yet? If you want to know how you might best mod your new board's AVCC power that might be a good idea.

Also, not sure if you should start a new thread for it but I would like to see some good, close-up, in-focus, hi-res pics of every part of the board. I would like to read part numbers and visually follow traces. How about that?

Last edited by Markw4; 20th June 2018 at 04:51 PM.
  Reply With Quote
Old 20th June 2018, 05:29 PM   #1539
Mikett is offline Mikett  Canada
diyAudio Member
 
Join Date: Aug 2003
Location: Toronto
Actually, I had planned on doing that but that reminds me that DIM DIM blog somewhere did measure the current requirements for AVCC. Let me find it.
  Reply With Quote
Old 20th June 2018, 05:30 PM   #1540
Mikett is offline Mikett  Canada
diyAudio Member
 
Join Date: Aug 2003
Location: Toronto
Yes, I put an ES9028Pro on my Buffalo III | Dimdim's Blog

There's a table!!!!!!

Then there's more about currents Vdd I see
ES9028Pro power wows | Dimdim's Blog

Last edited by Mikett; 20th June 2018 at 05:52 PM.
  Reply With Quote

Reply


ES9038Q2M BoardHide 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
My Cambridge 500SE, needs an output board (to replace internal DAC Board) slbender Digital Source 1 11th July 2018 02:43 AM
JLSounds XMOS USB board + AK4396 board + Direct DSD PCB ravid Swap Meet 1 29th December 2016 11:36 AM
Unknown Board DC12V TPA3116 amplifier board DIY L163-9 AUS Ben Class D 0 8th December 2016 04:05 AM
FS: Ian FIFO i2s-to-PCM board, Single XO clock board trung224 Swap Meet 3 26th November 2016 02:18 PM
Lost 1 Zv4 ckt board..looking to buy 1 circuit board Blues Pass Labs 1 22nd March 2004 10:09 PM


New To Site? Need Help?

All times are GMT. The time now is 06:14 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki