That's interesting. Did you have to desolder the on-board clock or just bypass it?
I wrote about replacing the clock back here: http://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-130.html#post5446706
Cheers, I shall study that.
Although given the state of my board, I've got many other things to address before I get as far as a clock upgrade.
I plugged the board in to check it still works and it does, but still fuzzy and distorted.
Clearly, in the process of replacing that damn cap I've done quite a bit of damage somehow.
Although given the state of my board, I've got many other things to address before I get as far as a clock upgrade.
I plugged the board in to check it still works and it does, but still fuzzy and distorted.
Clearly, in the process of replacing that damn cap I've done quite a bit of damage somehow.
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To follow up a little bit on the jitter distortion improvement mod using the Arduino and shield described previously: http://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-196.html#post5490345 and: http://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-142.html#post5452170
It turns out I was able to get the DSD DPLL bandwidth down to the 3rd from the lowest setting by moving the I2S ribbon cable around a little, and by putting my finger on one of the clocks on the AK4137 board. Could be if those clocks were upgraded to lower jitter types, it might then be possible to reduce DSD DPLL bandwidth to the minimum. That would be expected to provide another audible improvement in sound quality.
A couple more things about adding an Arduino, besides better sound quality from reduced jitter, (1) an Arduino would permit adjustment of the harmonic distortion compensation registers (useful for those with a sound card and notch filter to measure distortion), and (2) the benefits of Arduino for DPLL and HD compensation should work for pretty much any of these Sabre DAC boards. For the board in this thread, the built-in microcontroller never accesses those registers so they are always at the default values. That is likely true for the other Sabre boards unless they have some option to adjust DPLL and HD using the display module UI.
It turns out I was able to get the DSD DPLL bandwidth down to the 3rd from the lowest setting by moving the I2S ribbon cable around a little, and by putting my finger on one of the clocks on the AK4137 board. Could be if those clocks were upgraded to lower jitter types, it might then be possible to reduce DSD DPLL bandwidth to the minimum. That would be expected to provide another audible improvement in sound quality.
A couple more things about adding an Arduino, besides better sound quality from reduced jitter, (1) an Arduino would permit adjustment of the harmonic distortion compensation registers (useful for those with a sound card and notch filter to measure distortion), and (2) the benefits of Arduino for DPLL and HD compensation should work for pretty much any of these Sabre DAC boards. For the board in this thread, the built-in microcontroller never accesses those registers so they are always at the default values. That is likely true for the other Sabre boards unless they have some option to adjust DPLL and HD using the display module UI.
I've repaired my board, there is now a circuit between pin 8 of the op amp and the positive terminal and no shorts to ground that I can find.
So I powered it up using a battery I made from four 18650 cells and there is no change n the SQ, it still sounds awful, fuzzy and distorted.
I just wish I'd listened to the board before making any changes to it so I would have known whether it was a faulty board or not.
So I powered it up using a battery I made from four 18650 cells and there is no change n the SQ, it still sounds awful, fuzzy and distorted.
I just wish I'd listened to the board before making any changes to it so I would have known whether it was a faulty board or not.
Well, these boards do sound pretty bad while still unmodified. And changing opamps and caps doesn't help much. We do know what helps though, but it requires some fabrication. There are easier ways that make modest improvements and more involved ways that make much greater improvements. If you want to start with the modest stuff first and you don't like it then you will have to throw it away and start over to get to the good stuff. So, You kind of need to have some idea of what you want to do.
What I'm concerned about is that this board is faulty as it really sounds so bad it's unlistenable, hence I say I wish I had listened to it before I made any changes to it so I could be sure that the rotten sound isn't my fault and due to some changes I've made.
Running off a battery which should be very clean DC, I'm sure it really shouldn't sound this bad.
I'm not giving up this easy of course, I'm going to build the linear regulated PSU as soon as the last parts arrive, then I might have to bite the bullet and buy one of the green versions and not mess it up like I have this blue one.
Running off a battery which should be very clean DC, I'm sure it really shouldn't sound this bad.
I'm not giving up this easy of course, I'm going to build the linear regulated PSU as soon as the last parts arrive, then I might have to bite the bullet and buy one of the green versions and not mess it up like I have this blue one.
Hi all.
I dont write much in this forum, but i read alot
I got this board about a month ago (version 1.07), and did some basic upgrades (dual dc power supply for the board, low noise power supply for the amanero which made a difference in audio)
Could you please advise the next steps?
from what i understand modifying the board to current state is the way to go.
also changing the clock?
I dont write much in this forum, but i read alot
I got this board about a month ago (version 1.07), and did some basic upgrades (dual dc power supply for the board, low noise power supply for the amanero which made a difference in audio)
Could you please advise the next steps?
from what i understand modifying the board to current state is the way to go.
also changing the clock?
Attachments
To fully modify the board for best sound quality is rather involved. Can't say if anyone besides me has done everything we know how to do so far.
How about if I post some links here to prior posts that are good for taking a look at and talk about various things that can be modified? After taking a look it may be possible to get a better idea of what can be done.
Before I do that though please let me summarize the mods, they include improved power supplies including more on-board local regulators for some parts of the circuitry, a very special and very critical power supply called AVCC, new analog output circuitry including current to voltage conversion (I/V) and differential summing stages, a new clock, an external upsampling board, an Arduino microcontroller to augment digital control of the DAC chip, and a modified cheap ebay LME49600 headphone amp to clearly hear DAC sound quality performance (the 1/8" jack on the board loads down the opamp and should not be used for headphones).
Lot of stuff in that list, right?
Here is a link to some ESS documents that should all be studied: ESS Technology :: Downloads
I will attach a file below with some links to thread posts of possible modding interest.
How about if I post some links here to prior posts that are good for taking a look at and talk about various things that can be modified? After taking a look it may be possible to get a better idea of what can be done.
Before I do that though please let me summarize the mods, they include improved power supplies including more on-board local regulators for some parts of the circuitry, a very special and very critical power supply called AVCC, new analog output circuitry including current to voltage conversion (I/V) and differential summing stages, a new clock, an external upsampling board, an Arduino microcontroller to augment digital control of the DAC chip, and a modified cheap ebay LME49600 headphone amp to clearly hear DAC sound quality performance (the 1/8" jack on the board loads down the opamp and should not be used for headphones).
Lot of stuff in that list, right?
Here is a link to some ESS documents that should all be studied: ESS Technology :: Downloads
I will attach a file below with some links to thread posts of possible modding interest.
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I will attach a picture below of the full test setup as it exists today.
If not familiar with how photos work when viewing in the forum, you can click on a photo to open it for viewing. While it is open if you hover the mouse over the lower left corner, a white X may appear which would indicate the picture is not being displayed at full size. Clicking on the white X will open the picture at full resolution.
It is also possible to right click on an opened picture and select to download it for viewing on the local computer.
EDIT: Found I forgot to include a link in the last post to pics of pin lifting the microcontroller to allow connection of the Arduino:
http://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-78.html#post5412858
If not familiar with how photos work when viewing in the forum, you can click on a photo to open it for viewing. While it is open if you hover the mouse over the lower left corner, a white X may appear which would indicate the picture is not being displayed at full size. Clicking on the white X will open the picture at full resolution.
It is also possible to right click on an opened picture and select to download it for viewing on the local computer.
EDIT: Found I forgot to include a link in the last post to pics of pin lifting the microcontroller to allow connection of the Arduino:
http://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-78.html#post5412858
Attachments
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hi, and thanks alot for the info.
im already reading the ESS document, but from what I understand the capacitors and resistors are already good enough.
please note that the v 1.07 already has the selection of the dac filters and the volume control from the potentiometer.
Ill read some more and come back!
im already reading the ESS document, but from what I understand the capacitors and resistors are already good enough.
please note that the v 1.07 already has the selection of the dac filters and the volume control from the potentiometer.
Ill read some more and come back!
I've recorded a 40 second clip of my board playing back a VBR MP3 using my Auna CM600 condenser mic, saved as a VBR MP3 it's a 901kB file but I can't upload it here, I get the error 'invalid file type'.
So I uploaded it to Google Drive:
CCR.mp3 - Google Drive
The distortion is actually less obvious than it is when hearing it 'live' so to speak, but the lack of low frequencies, the fuzziness and the overall crappy quality should still be obvious I think.
So I uploaded it to Google Drive:
CCR.mp3 - Google Drive
The distortion is actually less obvious than it is when hearing it 'live' so to speak, but the lack of low frequencies, the fuzziness and the overall crappy quality should still be obvious I think.
The LT3042 is the 5v supply for the SRC boards and for the DAC board. All of those board then have one or more 3.3v regulators locally. Just used the LT3042 for that because I had it and it was handy, it's probably overkill.
The LF sounds buzzy like there is a ground loop or something, or maybe some hum from exposed wiring. Other than that it sounds about like these boards do. How are you feeding the DAC digital input? Do you have a volume pot hooked up to the dac?
Rather than use a power amp, a speaker, and a mic to record with it would probably be much more accurate to use the DAC output as the mic signal, just make sure it doesn't overload the A/D inputs. Also, record to wav not mp3, the sound quality would be much more accurate.