I have the rev.1 board and haven't had any clicks for a long time. This new 1.20 firmware works fine as well here. Have only tested the USB-> I2S input with the following sample rates 44.1, 48, 88.2, 96 and 192. All good although when in play mode I have to enter the filter command (F4-F7) twice for it to work. Might be a comm. port thing. This interface has never been 100% stable on my Windows laptop.
I finally got around trying out the Rev 5 DAM1021 I had bought a few months ago.
I only added a 7V transformer and the S/PDIF input circuit. I did not impliment a volume control. Stock filters. I'm listening through the XLR outputs.
So far: Good detail, definition, the converter easily shows inadequcies in the recording equipment.
The sound is quite effortless and smooth, but also a little too controlled, technical, a little anemic, bass could exhibit more movement (slam) and I'd like more overall liveliness.
The old Troisi mastering converter with an R2R chip I monitor through sounds more musical so far.
What can be achieved by a) applying DC (simple unregulated PSU with diode bridge and caps) b) switching to a different digital filter c) applying mods to the board (regulators, output filter etc.) d) usind the unbalanced outputs or changing the output op amp (or adding decoupling there)?
From my experience there are few op amps that sound good, and I mostly end up with the NE5534/NE5532 in my studio gear. Has anybody replaced the output op amps on the DAM1021?
Thanks!
I only added a 7V transformer and the S/PDIF input circuit. I did not impliment a volume control. Stock filters. I'm listening through the XLR outputs.
So far: Good detail, definition, the converter easily shows inadequcies in the recording equipment.
The sound is quite effortless and smooth, but also a little too controlled, technical, a little anemic, bass could exhibit more movement (slam) and I'd like more overall liveliness.
The old Troisi mastering converter with an R2R chip I monitor through sounds more musical so far.
What can be achieved by a) applying DC (simple unregulated PSU with diode bridge and caps) b) switching to a different digital filter c) applying mods to the board (regulators, output filter etc.) d) usind the unbalanced outputs or changing the output op amp (or adding decoupling there)?
From my experience there are few op amps that sound good, and I mostly end up with the NE5534/NE5532 in my studio gear. Has anybody replaced the output op amps on the DAM1021?
Thanks!
When I changed the filter to the NOS one the technical part went away, everything sounded more organic and the bass got more definition. I made quite a not foreseeing impact and it’s easy to do. The filter is part of the last firmware.
If you’re interested I’ll dive into my notes what’s the name of that filter
BTW I have a supperregulator DC powersupply for the dam1021 but the filter setting still made a good change.
Thanks maikel76! Is there a way to change the filter without a serial interface? I would have to dig out an old laptop for that...
I’m afraid not. An old laptop will do. Use the ISO serial connection, it’s easier
In my case I couldn’t get J10 serial to work but I could get isolated serial on J3 to work.
That was just my experience, what Randy said makes sense too.
I vaguely remember the isolated serial connection is TTL level and requires a 3.3V signal level, but the non-isolated one works with 5V (not sure if it also works at 3.3V).
I haven't connected to mine via serial for 2 years or so, but I do remember I have 2 USB-Serial adapters, one with a TTL (3.3V) level that I use when connecting via the isolated connection and the other with a 5V level for the regular connection.
AND I found, like Randy, that the non-isolated one was a little easier to get a connection on, but both worked when using the appropriate level output.
See HiFiDuino, this post, for some of the info... the rest is as I remember in this main thread many posts ago:
The Soekris R-2R DAC: Technical Details | H i F i D U I N O
Search for 'serial'.
Greg in Mississippi
I haven't connected to mine via serial for 2 years or so, but I do remember I have 2 USB-Serial adapters, one with a TTL (3.3V) level that I use when connecting via the isolated connection and the other with a 5V level for the regular connection.
AND I found, like Randy, that the non-isolated one was a little easier to get a connection on, but both worked when using the appropriate level output.
See HiFiDuino, this post, for some of the info... the rest is as I remember in this main thread many posts ago:
The Soekris R-2R DAC: Technical Details | H i F i D U I N O
Search for 'serial'.
Greg in Mississippi
Aah thanks Greg, that totally makes sense. I connected my ISO serial to a raspberry pi, which indeed uses TTL level.
DSP and two DAM 1021
I have until now used one dam1021 followed by an electronic crossover. I have however been intrigued by trying two dam2021 with a Minidsp Nanosharc. It works flawlessly. I have not had time yet to check out the sound quality, but I have high expectations, also now having the option to easily play with different filter options.
I have until now used one dam1021 followed by an electronic crossover. I have however been intrigued by trying two dam2021 with a Minidsp Nanosharc. It works flawlessly. I have not had time yet to check out the sound quality, but I have high expectations, also now having the option to easily play with different filter options.
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Hi Soren
i just installed the update on a v3 board and unfortunately it did not solve the issue with the clicks. The clicks are on the toslink connection as well as on the i2s line from the raspberry.
Going back to 1.06 solves the issue.
Best Tobias
Just for info, we have added an US online reseller, I know many of you have been waiting on that, they will carry the whole lines of dams and dacs.... Please visit them at:
https://www.modhouseaudio.com/
https://www.modhouseaudio.com/