ackoDAC based on ES9018

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Thanks GLT,

So do I need arduino to do the reg 15 programing or is their a guru command I can run when I am programing ackodac with the documented MCU commands? Currently I only have access to the documented commands not the white paper or datasheet I keep reading about that supposedly has all the register commands.

thanks,

Will
 
8CH DAC

Hi Acko and all,

How would I go about connecting the ackodac in 4 channel quad mode? I have the 8 channel version. I will be connecting it to the exa transport via i2s. Also, as far as register settings, what are the optimal settings for my configuration? I want to run with the ASRC and oversampling on.

thanks,

Will

Hi Will,

The 8CH version has a straight 8-in 8-out arrangement. Of course for 8-Channel audio it is pretty straightforward to connect to 8 channels sources like the EXA. The default setting with the 8CH controller AKC18 is I2S source and all the others as chip factory default for 8CH . You can change settings to suit with the MCU and save to its NV mem

You can also have other combinations of I/O to suit. The EXA manual shows how a quad config is connected.
 
Thanks GLT,

So do I need arduino to do the reg 15 programing or is their a guru command I can run when I am programing ackodac with the documented MCU commands? Currently I only have access to the documented commands not the white paper or datasheet I keep reading about that supposedly has all the register commands.

thanks,

Will

Will,

You can use the supplied MCU (AKC18) or Arduino to program any of the exposed registers. Datasheet will be very useful. Try getting a copy from ESS or Shaw Electronics. The supplied functions is for convenience only and may not cover every possible configuration, so direct register commands needed for specifics and then issue the SAVE command of AKC18 to store settings in the NV memory of AKC18.
 
Acko and Glt,

Thanks for helping me with this. The manual I have is for the Akc12, is there a new manual for the akc18? When I run the &volm command I get back &volmff as a response. So this means my volume is turned all the way down? I'll try turning the volume control to see if this changes. I will be summing the outputs for SE so I guess I will need to mess with regs 13 and 19 in addition to 15 for the quantization? My attempts so far to run any set commands (~) in putty, when connected to com3, result in "Comcode? error!" I can run the (&) commands and see the values fine. I'm waiting to hear back from shaw on the datasheet. Do I have to do something else in putty to get the set commands to work? When I run ~dacs1 to reroute the inputs I get the com error, same with running ~firs0 ??

thanks again,

Will
 
I was able to get past comcode errors, I simply made the set commands case sensitive and that worked. And I tested vol and it appears I had all of them turned all the way down. When It comes to setting other registers I'm mainly concerned with polarity since I need to run this SE. Do I mainly concentrate on reg 19 settings?
thanks,

Will
 
hmm, you know although its an option to run all the outputs in the same phase, since you are running 4 channels if it were me i'd be running balanced and summing externally in the IV stage with some sort of instrumentation amp, i reckon you'll get better performance this way
 
Thanks Glt,

That is exactly what I needed to know, so summing the dacs doesn't do anything to their phase? I don't need to make any changes to reg 13 then?

Will

I suppose you will want to have the DACA's also in-phase. That will be 0x00 in reg13. Summing the DACs at the output will either reinforce (if two signals are in-phase) or cancel out (if the two signals are in anti-phase). I suppose you are trying to sum all 16 DACs at the output?
 
Manuals

Acko and Glt,
The manual I have is for the Akc12, is there a new manual for the akc18?

Will,

I thought I sent you the manual for the 8CH DAC Controller (AKC18). Anyway, I will send a copy again.

The other thing I realised is this standard controller (AKC18) has all 8 channel Vol and may not exactly suit your quad mode setup or other variations from physical controls point-of-view. Once you get your project specs firmed up I will be happy to create a special build of the controller and even the IV stage(ic version only) to match

Also, for the rest if you wish to browse the AckoDAC manuals. please feel free to contact support or PM.
 
SE Outputs

Just a word of caution with setting SE outputs with the DAC:

Whilst it is possible to set the outputs in phase and sum them to get true SE outputs, there is a ~1.65V offset to cancel out in the subsequent IV stage. Yes you can counteract this will a simple offset adj circuit but then any drift will upset this and nulling is again required. Then you are looking at offset monitoring/ auto-adj circuits like integrators and other elaborate techniques. On the other hand a balanced output setting of the DAC inherently cancels this offset and drift by the very action of CMR of a differential input IV, all nice and simple.

I did contemplate this true SE mode at one stage especially for SE gear but abandoned this after realising the above. So for SE equipment, DAC is output is set balanced and IV has balanced inputs followed by balanced to SE conversion as required.
If anyone has other understanding on this matter please free to advise.
 
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Hey Guys appreciate all the feedback and help.

I plan on trying this in Voltage mode for now, Yes with a cap, BG Ns is what I thought might work well, I had four lying around so why not? I do plan on figuring out a decent I/V and some sort of bal to se circuit after I get the balanced signals out. I like simple and to try out different things, I know that voltage mode is not ideal for this dac. But I've heard it still can sound good this way. I'm still blown away by the swenson mod I tried a few years back on my universal player, which had a voltage out dac chip, I expect ackodac to sound better this way. I'm positive it will once I move to I/V. I need to research further whether to go IC or discreet.

With your help I at least have all of the settings saved to memory now and I will let you know how it sounds in the next few days, It'll need a while for the BGs to break in though. What do you guys think as far as the IIR setting, the default was set at DCD 70k?

Acko, I will probably just let the volumes run full open at the DAC and control it either at the amps or most likely by the computer application. No need for a special build or anything but I appreciate it. I might down the road try and use all 8 channels so...

Thanks again,

Will
 
noooo, is your next stage so low impedance that you need to use an electrolytic? i really wish this myth that blackgates are as good as a decent film cap would die; use a polypropylene film and foil cap, forget the blackgates; sell them to someone for a silly sum, or use them in power supply somewhere.

sorry its a bit of a pet peeve of mine, use them if you have them i guess, but films would be better for signal coupling. blackgates are a good electrolytic, but they are still an electrolytic. There is no such thing as voltage mode, directly coupling the dac to a cap and a reactive load is about the worst condition for the dac, yes it works for a test, but you dont get anywhere near the quoted 'voltage mode' specs.
 
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