0dB is the maximum volume. This is the maximum volume that does not damage the sound quality. Az1021's firmware has a memory function, and each time it turn on the last shutdown state, it also includes the volume. If you need to fixed the dam1021 default settings, you need to connect the computer with the RS232 port to fixed it.
Hallo Audiozen
The official current consumptation of the
dam1121: 350ma@5V and
XMOS 384 USBtoI2S module: 200mA@3,3V
Maybe the items need more under certain circumstances?
This is at the limit of your data. Is it a good idea to use your "SK lite" as a PSU for these parts or a external PSU?
I will just use USB as the source
for the analouge part of the dam I will use a solid PSU....
greetings
Last edited:
I use powered monitor speakers - 0 dB could be quite loud
I've just had a poke around the uManager interface, and couldn't find anything interesting:
Code:
# set
Conspeed = 115200
Volume = -99
Filter = Linear
Mode = NormalWhen the unit boots, I see this out of the RS232 interface (without typing "+++"):
Code:
R1.06
I3
L000
F4
V+00
I3
I0
F5
V-20
I0
L048
L048It *seems* like that V+00 would have been in response to a command from your ST MCU, but I haven't sniffed the isolated serial interface to confirm that yet.
Do you know what I need to type into uManager to set the boot/startup on the dam1021?
The question was if it is a good idea operating the sk-lite PS at the limit all the time.
am1121: 350ma@5V and
XMOS 384 USBtoI2S module: 200mA@3,3V
Or better use an additional PSU?
thank you
No. Sören says its the job of the "computer" controlling it. I think it is poor design as a computer may have an idea but it is stil what is in the register of the DAC that ultimately sets the attenuation - so why not present it? Please an FW feature for this!
//
Last edited:
Am I right the connections between the SK-lite and a dam to controll the dam is just Pin 5+6 from the "ISO" connectors block?
If I am right the "ISO TXD Out" and "ISO RXD In" pin doesn't exsist at the dam1121 (oem).
How do I connect the SK-lite with an dam1121 (oem)?
Is it "COM RXD" and "CON TXD" at block J2? Are these all connections between SK-lite and dam1121?
If I am right the "ISO TXD Out" and "ISO RXD In" pin doesn't exsist at the dam1121 (oem).
How do I connect the SK-lite with an dam1121 (oem)?
Is it "COM RXD" and "CON TXD" at block J2? Are these all connections between SK-lite and dam1121?
Last edited:
Yes, it remembers the set startup volume
(I don't think what you set last i.e. "V-25" etc, but the "Set Volume -20")But it cant remember changes as they are set. There is no way of asking a DAM what the current, playing, attenuation is - this I would like to see.
//
Last edited:
It’s a bit of a ‘chicken and egg’ scenario. The DAM has to be fully booted up to receive a volume command from any ‘computer’ sending it such a command.
The DAM also boots faster than most ‘computers’ (micro controllers running a program) and also has a source auto select feature.
So, it is entirely possible for the DAM to select an active source quite a bit before the controller (uC) sends it an initial attenuation command. Hence the momentary 0db blast mentioned above.
To get around this, what I believe audiozen is suggesting is to use the DAMs initial startup volume command. Which, of course, has to be set by the owner of said DAM as audiozen doesn’t (to my knowledge) supply the DAM with his kit.
If successfully done (and I’m not sure it was successfully accomplished above) then, on first powering up, this would prevent the blast. Soon after this the uC should send it’s command to the DAM for an initial volume setting. The DAMs echo all commands sent to them so at this point the uC (a) knows what attenuation level it has sent and (b) can get a confirmation from the DAM if so programmed.
Assuming the uC is powered on and off at the same time as the DAM and it is the only device controlling the DAMs attenuation setting etc it doesn’t really need to ‘query’ the attenuation level of the DAM as it already ‘knows’ it.
[special=]%[/special]Essentially, the uC is the one in control once it gets going and the DAM is ready to receive commands. It’s just that period of time when, because the DAM boots so fast, it can play a source at a 0db level unless the startup volume on the DAM itself is set to substantially less than 0db.
The DAM also boots faster than most ‘computers’ (micro controllers running a program) and also has a source auto select feature.
So, it is entirely possible for the DAM to select an active source quite a bit before the controller (uC) sends it an initial attenuation command. Hence the momentary 0db blast mentioned above.
To get around this, what I believe audiozen is suggesting is to use the DAMs initial startup volume command. Which, of course, has to be set by the owner of said DAM as audiozen doesn’t (to my knowledge) supply the DAM with his kit.
If successfully done (and I’m not sure it was successfully accomplished above) then, on first powering up, this would prevent the blast. Soon after this the uC should send it’s command to the DAM for an initial volume setting. The DAMs echo all commands sent to them so at this point the uC (a) knows what attenuation level it has sent and (b) can get a confirmation from the DAM if so programmed.
Assuming the uC is powered on and off at the same time as the DAM and it is the only device controlling the DAMs attenuation setting etc it doesn’t really need to ‘query’ the attenuation level of the DAM as it already ‘knows’ it.
[special=]%[/special]Essentially, the uC is the one in control once it gets going and the DAM is ready to receive commands. It’s just that period of time when, because the DAM boots so fast, it can play a source at a 0db level unless the startup volume on the DAM itself is set to substantially less than 0db.
@zxc The DAMs both have a volume range of -80 to +10. So, setting their startup volume to -90 as you mentioned will not have the desired effect as -90 is an invalid command. Set it to -80. Then, power cycle the DAM with the terminal software running and you should see -80 as your first attenuation level.
Last edited: