I've now taken delivery of my Soekris 1121-01 R2R DAC board. First impressions after unpacking it are of a very nice neat board that is of a high quality product. There are an awful lot of tiny smd parts packed onto this small PCB!
I will feed I2S signals (no SPDIF required) into the R2R board courtesy of a JLSounds USB board. This features galvanic isolation (from USB noise) and reclocks the I2S output so the 1121-01 will receive a good quality data stream (I know the 1121-01 reclocks after the FPGA as well).
I have ordered some very low noise regulated power supplies courtesy of AckoDAC, and an AudioZen SK Lite module to take care of control aspects.
My implementation will be a single 1121-01 for stereo single-ended outputs, which I will pass to a tube buffer.
I'm currently working on a small PCB that will connect the JLSounds with the Soekris (it provides the I2S and comms. interfaces as well as setting the initial startup config. straps).
As you chaps have more experience of the 1121-01 can I just confirm my configuration settings before I finalise my interface PCB;
CFG0 (J2-4) - pulldown to ground via 1K0 resistor
COM_RXD (J2-10) - connect to serial receive wire via 1K0 resistor
COM_TXD (J2-12) - connect to serial transmit wire (without resistor)
I2S_DAT_0 (J3-7) - pulldown to ground via 1K0 resistor
I2S_LRCK_0 (31-9) - pulldown to ground via 1K0 resistor
I2S_BCLK_0 (J3-11) - pulldown to ground via 1K0 resistor
EN_AUD (J1-2) - leave unconnected
(I've assumed relevant ground connections will be made)
I believe those settings will enable the 1121-01 to boot correctly for my required configuration and to communicate with the serial controller (either via a PC or the SK Lite.
Cheers
Ray
I will feed I2S signals (no SPDIF required) into the R2R board courtesy of a JLSounds USB board. This features galvanic isolation (from USB noise) and reclocks the I2S output so the 1121-01 will receive a good quality data stream (I know the 1121-01 reclocks after the FPGA as well).
I have ordered some very low noise regulated power supplies courtesy of AckoDAC, and an AudioZen SK Lite module to take care of control aspects.
My implementation will be a single 1121-01 for stereo single-ended outputs, which I will pass to a tube buffer.
I'm currently working on a small PCB that will connect the JLSounds with the Soekris (it provides the I2S and comms. interfaces as well as setting the initial startup config. straps).
As you chaps have more experience of the 1121-01 can I just confirm my configuration settings before I finalise my interface PCB;
CFG0 (J2-4) - pulldown to ground via 1K0 resistor
COM_RXD (J2-10) - connect to serial receive wire via 1K0 resistor
COM_TXD (J2-12) - connect to serial transmit wire (without resistor)
I2S_DAT_0 (J3-7) - pulldown to ground via 1K0 resistor
I2S_LRCK_0 (31-9) - pulldown to ground via 1K0 resistor
I2S_BCLK_0 (J3-11) - pulldown to ground via 1K0 resistor
EN_AUD (J1-2) - leave unconnected
(I've assumed relevant ground connections will be made)
I believe those settings will enable the 1121-01 to boot correctly for my required configuration and to communicate with the serial controller (either via a PC or the SK Lite.
Cheers
Ray
Ray, just two quick observations - the COM_RXD connects to the serial transmit wire, not the serial receive wire. And the COM_TXD connects to the serial receive wire. Correct re the resistor on the RXD line.
Secondly, FWIW, the DAM 1121 manual actually specifies a 3.3k resistor as the recommended value for the pullup/pulldown Config Straps. The 1k value is a minimum value and, subject to memory, I believe TNT had an issue awhile back in this thread and had to go with higher value strap resistors. I myself have built two 1121s, one single-ended like you plan and a dual-mono and used 3.3k successfully. YMMV.
parallel it with another LED the current consumption of leds are quite low or just take the signal out as transistor ref and drive the larger LED with transistor if you are really concerned about the current consumption of LED.
I've finally started to assemble my Soekris DAM1121 DAC.
Having received the panels from Front Panel Express I've started by assembling and installing the AudioZen control unit - available from the Vendor Bazaar.
So, here are some pictures of progress so far. The AudioZen control unit is installed and working.
A more general layout image showing the Soekris DAM1121 module and the JLSounds USB board. The two Black PCBs are from Acko and are for the power supplies for the Soekris and JLSounds modules; they'll be next to assemble and install. The large empty area is where a Broskie Aikido (ACF-2) buffer will be located.
Having received the panels from Front Panel Express I've started by assembling and installing the AudioZen control unit - available from the Vendor Bazaar.
So, here are some pictures of progress so far. The AudioZen control unit is installed and working.
A more general layout image showing the Soekris DAM1121 module and the JLSounds USB board. The two Black PCBs are from Acko and are for the power supplies for the Soekris and JLSounds modules; they'll be next to assemble and install. The large empty area is where a Broskie Aikido (ACF-2) buffer will be located.
Hi, I am starting to work with DAM1121.
I connected the RXD/TXD pin to my laptop through a USB adapter. I have installed drivers and also babun emulator. Somehow my laptop could not recognize DAM. What might be the cause?
Also, without entering the uManager, will the DAM play at default? Right now nothing come out of it. I check all the power and nothing seem to wrong. Thanks.
I connected the RXD/TXD pin to my laptop through a USB adapter. I have installed drivers and also babun emulator. Somehow my laptop could not recognize DAM. What might be the cause?
Also, without entering the uManager, will the DAM play at default? Right now nothing come out of it. I check all the power and nothing seem to wrong. Thanks.
Did you see my blog?
It may help
soekris setup
I remember some 232 adapters didn't work, think it has to do with voltage levels. Blog has what I used.
Thanks, Randy, I did follow your post and downloaded extrapuTTY. However, when powering on, the screen does not return the messages about 1121 (version etc). Instead, I got a green block. I suppose it is a connection problem and maybe I need another USB-RS232 adapter.
Hi, Vit123, I do believe that the adapter I've got is the right one. I will have to double check. Even when I unplug the adapter, there was no sound. Your message confirms my guess that the board should work without opening uManager. I will double check all the connections. I hate to deal with those tiny pins and maybe I should make some PCB (such as the one in Nautibuoy's post that has DIP socket for J2 & J3). Cheers.
Hi, Vit123, I do believe that the adapter I've got is the right one. I will have to double check. Even when I unplug the adapter, there was no sound. Your message confirms my guess that the board should work without opening uManager. I will double check all the connections. I hate to deal with those tiny pins and maybe I should make some PCB (such as the one in Nautibuoy's post that has DIP socket for J2 & J3). Cheers.
I've been recovering from a cycling accident so my 1121 DAC project has been on-hold for several weeks. I resumed work on it this weekend and have it almost ready for an audition but I'm still waiting for delivery of some small PCBs rgat will interface the 1121 ro the JLSounds USB board; I just have the final hook up and some small tidying up tasks to do. The other main modules are an AudioZen DAC controller, DAC power supplies from Acko and a Broskie ACF-2 output buffer;
Last edited:
The Dam1121 is now playing music for me!
It is supposed to be able to play in stock form, no need to touch the uC. I am using Slagle autoformer as volume control. No output stage right now.
It didn't work a few days ago because I made the mistake and only connected ONE VCC5D power supply. The two pins are indeed for two sub-circuits. I did a measurement and the impedance between them is about 300K. All the GND's are connected with each other though, digital or analog.
I also just bought this bluetooth to serial adapter:
Wireless Serial 4 Pin Bluetooth RF Transceiver Module HC-06 RS232 With backplane | eBay
Since it accepts 5V VCC so I just use the VCC5D. Downloaded android app "Bluespp" but could not establish a connection right now since the connection needs a password. Need to check with the seller.
Cannot comment on the sound now since I only connect one channel, and the speaker is just a naked Tone Tuby 12" guitar driver (guitar drivers can take abuse just in case anything bad happens). Still I am thrilled and am liking it. Will report back.
Big thanks to Soren for the wonderful module! Cheers.
It is supposed to be able to play in stock form, no need to touch the uC. I am using Slagle autoformer as volume control. No output stage right now.
It didn't work a few days ago because I made the mistake and only connected ONE VCC5D power supply. The two pins are indeed for two sub-circuits. I did a measurement and the impedance between them is about 300K. All the GND's are connected with each other though, digital or analog.
I also just bought this bluetooth to serial adapter:
Wireless Serial 4 Pin Bluetooth RF Transceiver Module HC-06 RS232 With backplane | eBay
Since it accepts 5V VCC so I just use the VCC5D. Downloaded android app "Bluespp" but could not establish a connection right now since the connection needs a password. Need to check with the seller.
Cannot comment on the sound now since I only connect one channel, and the speaker is just a naked Tone Tuby 12" guitar driver (guitar drivers can take abuse just in case anything bad happens). Still I am thrilled and am liking it. Will report back.
Big thanks to Soren for the wonderful module! Cheers.