The system where these filters are tested and finetuned sure is sort of a reference point, but only for Paul's ears since we not all sitting in his livingroom/lab while he is happily tweaking away...
So it is a reference point for him and his subjective judgement of the filters he is creating and providing to the community. It is up to us to test those filters in our own surroundings and systems and evaluate whether we like them of not... in the end he is giving us hints what he tried to achieve and how it may sound.
The rest and the final verdict is up to us... which is perfectly fine with me. In the end everything in audio is subjective with everybody's perception and everybody's system different
So I am all with Priidik, Mr. R and Andrew.
I think you are taking this the wrong way. People are not complaining that you use BAL, but they are simply telling you "SE sounds way better than the not-so-perfect-balanced-converter and it would probably be easier to check the sound of the filters with the possibly best default hardware solution". Myself i'm usually at your side (i prefer balanced connection), but since it this time is not native - and not converted the best way, i would of course use the SE output or make a better converter myself.
So i think most people just want you to have the best possible sound when testing your filters - since you are the biggest contributor there.
So i know i am, and i think most people here are grateful for what you do here. Just try to calm down a bit and take it more like people is trying to help.
Nothing is wrong with creating and testing filters and leaving it up to everybody’s taste which one to use. I really appreciate it as I already have expressed at several occasions.
But it’s not so far fetched to be interested in the conditions around the filter creating process as in the end –individual taste or not- these kind of filters should and do represent more than just good sound in an individual setup as they are the sum of very specific decisions about parameters that forge the final sound of this DAC. The more we understand about all the reasons for those decisions (that would include the audio system) the better we can judge their audible effects and their value in our own system. That's all.
But it’s not so far fetched to be interested in the conditions around the filter creating process as in the end –individual taste or not- these kind of filters should and do represent more than just good sound in an individual setup as they are the sum of very specific decisions about parameters that forge the final sound of this DAC. The more we understand about all the reasons for those decisions (that would include the audio system) the better we can judge their audible effects and their value in our own system. That's all.
Having an issue with my dam, the INPUT SLCT1 and VOLUME_POT pins do not respond when shorted to GND. Only the INPUT SLCT0 pin does anything, therefore the dac cannot be put into any other mode other than auto select or toslink, and the volume control pot is totally unresponsive. All 3 pins measure 3.3V to ground so they appear to be still getting pulled up when open at least...
I checked the board and these 3 pins go straight into the microcontroller, seemingly without any input protection whatsoever. I'm hoping its just a software glitch but has anyone else experienced this?
Thankfully serial still works fine and I can make the changes there, but the hardware pins working would be nice.
I checked the board and these 3 pins go straight into the microcontroller, seemingly without any input protection whatsoever. I'm hoping its just a software glitch but has anyone else experienced this?
Thankfully serial still works fine and I can make the changes there, but the hardware pins working would be nice.
A possible solution to those wanting to keep the RS232 port connected all the time while still keeping it fully isolated from a noisy PC ground. Isolated USB TO RS232 Converter USB TO Serial 2 5KV Isolation | eBay
I did warn you guys what would happen if the crap about my system did not cease.
Take a bow.
Last edited:
Hi all,
Some questions about the dam1021:
- How much heat does it generate? Is it wise to mount the DAC in a compact aluminum case with no vent? Does the FPGA require passive heatsink?
- Is the AMB Sigma 22 a suitable PSU for a high-end build?
- When using the Sigma 22 PSU, is it wise to bypass (short) the onboard bridge rectifier?
- Which one sound better? The digital volume control or a quality stepped attenuator? Assume the raw output is used.
Thanks!
Some questions about the dam1021:
- How much heat does it generate? Is it wise to mount the DAC in a compact aluminum case with no vent? Does the FPGA require passive heatsink?
- Is the AMB Sigma 22 a suitable PSU for a high-end build?
- When using the Sigma 22 PSU, is it wise to bypass (short) the onboard bridge rectifier?
- Which one sound better? The digital volume control or a quality stepped attenuator? Assume the raw output is used.
Thanks!
i wish there was a cap on how many stupid people that could exist in the world, but i guess there's not.
Even though someone, who is tirelessly producing filters for us, explicit ask people to stop craping down on how his setup looks like, there always seems to be a few that need some last sentences. I guess that the rest of us can assume that you will pick up the baton and continue to do simulations, pictures, explanations and filters in the same pace as spzzzzkt so we can continue enjoying our DAM instead of making it a dead piece of meat
Even though someone, who is tirelessly producing filters for us, explicit ask people to stop craping down on how his setup looks like, there always seems to be a few that need some last sentences. I guess that the rest of us can assume that you will pick up the baton and continue to do simulations, pictures, explanations and filters in the same pace as spzzzzkt so we can continue enjoying our DAM instead of making it a dead piece of meat
If you didn't understand i was trying to be the middle man here. The big problem here i think (from both sides) is bad attitude, you gave your version why you used balanced, people gave their version of why you should try SE. I'm just trying to make the both sides point get through (because it seems it have not). Anyway, i don't care what either you or other people use. Just read what i said. I and i think everyone here is really grateful for what you do! take it as a compliment.
@spike Soren acknowledged this previously. Should be fixed in the next firmware update. Now the only reliable way to switch inputs is to use the I0/1/2/3 commands, I think. Or if you don't use USB, just one digital signal connected.
Last edited:
This looks pretty nice. It should work just fine.
I myself will wait for Soren's new firmware that will support isolated serial connection.
But beware: the isolated serial port will be TTL and so only capable of "talking" to TTL devices (a.k.a. little 2$ USB to Serial converters). Plus, though it will be isolated from the DAM, it will not be isolated from the USB to I2S interface board since they will share a common ground.
The input selection pins simply do not work correctly, which is very annoying if you have several digital sources. Presumably it is a firmware problem and hopefully will get fixed someday. See post #1913.
The volume pot pin should work and the volume should be turned down if VOLUME_POT is connected to GND. However, it will go to the maximum +6dB level when the VOLUME_POT pin is disconnected, which results in distorted sound with most recordings.
@soekris
I would like you to consider the possibility of having the volume setting go to 0dB whenever the VOLUME_POT pin is disconnected. It would allow for a simple implementation of volume adjustment bypass button.
It does get warm, maybe 35deg on surface of some ic-s, aluminum case should be fine. No extra heatsinks are required by design, the pcb presumably has a solid ground plane which helps to take care of heat dissipation.
I doubt a stepped attenuator makes any difference in sound quality, the attenuator is not directly on signal path.
Sigma 22 looks great, but i have not used it myself.
The hottest component in my setup is the heatsinked 7812 regulator of the +12V BiB supply. The DAM board itself only has the 3.3V LDO that gets a bit warm. As you can see the little blob to the right is the FPGA, which is cold in comparison to the LDO and dual 5V regulators nearby.
Last edited: