ADAU1467 Evaluation board?

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Hello.

I have been reading up on the ADAU1467 EVM, more specificly, the components involved, circuit layout, and features.

Really starting to consider purchasing one of these EVM's to use on a permanent basis in one of my setups.

Pieces involved:
AD1937 as ADC/DAC, this is a 4 in 8 out chip, that can be daisy chained for more ins and outs if needed. Specs give 112db S/N figures at -60db input, whatever that means, and -86db THD+N all eight outputs running at the same time. This is measured at 48khz sampling rate, maybe there can be a little something to gain from running 96khz? I do not know. Are they measuring it this way to give some form of realistic numbers should one choose to run a pre-amp before the chip? I do not know.

The ADAU1467 chip itself itself boasts 139db dynamic range and -120db THD+N for the sample rate converters. Other than the large number of fancy functions expected.

ADA4610-1 JFET op amp Buffers the common-mode output of the AD1937 codec for distribution to the analog filters.

ADA4841-2 Low noise op amp. Implements the analog audio filtering required for the stereo line inputs and outputs

Eval board summary:
There are settings for all sorts of things, for instance master clock and PLL mode, they have also put 2 10kohm potmeters on the PCB, these potmeters are configureable through the SigmaDSP system, and as far as I can tell limited to almost any function you can make variable!
Inputs outputs: there are 2 sets of stereo Analog In, 1 optical in, 1 optical out, 4 sets of stereo analog out.

The Eval board is not very expensive, and it seems it might make a reasonable all-in-one solution as a pre amp + dsp thing.


People smarter than me please tell me the pro's and cons!
Because all I'm seeing is a great thing that solves all my needs/wants, so help the blind here!

Good match for 2 x TPA3255 EVM's in BTL?

ADAU1467 Datasheet and Product Info | Analog Devices
 
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I've been short on cash for a while now, but finally things are shaping up again, seeing as the ADAU1467 has not been in stock yet, I very recently noticed the EVM board for the younger sibling, the ADAU1466 completely unexpected IN STOCK on mouser, and ordered it immediately. Price is the same, specs a tiny bit lower than the '67 but the layout is more practical for my needs/wants.

Just got the ADAU1466 in the mail, and it's tiny! :)

Such a cute little thing. have not had the time to look at it properly yet, so much going on. maybe I'll get to play with it sometime this weekend. So excited!

Have been unhappy with my PC based XO's for some time now, no matter what program or solution I end up with it feels like too much of a compromise, for some reason I get glitches periodically no matter what the buffer settings are. And it does not sound as "transparent" as I would like. Not sure if this EVM board will be the holy grail either, but very ready for a change, and also just use optical out to break some other issues as well.
 
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Been able to give priority to look at the Sigmatudio program a little bit.
It is so full of functionality that it is a little bit hard to get going, but I've managed to get some filters going (had to play around a bit to get it right), set up volume control via one of the aux adc potmeters (which was REALLY tricky). The not-so-obvious thing for me at first was that you have to set up EVERYTHING including channel mapping on the internal matrix. It is very easy NOW, but for a while there I could not understand why the f*** there was no audio in on my level meters at all.

Slowly plodding along, but so far it's really promising, using 48khz/32bit and just testing out stuff, but not far from the program I will use permanently.
Next on the list is trying to use the other on-board aux adc potmeter as an input source selector, will probably have to run through some logic functions to get there.

If there's anyone else out there that took the plunge on one of these eval boards it would be nice to exchange some tricks.
If there's any need for my absolute n00b setup, just ask and I will try and contribute in any small way, might be helpful.
I'll post my setup if anyone is interested in my partial success, if not I'd rather wait until I got it all nailed down.

Kent
 
First of all:
Read the ADAU1701 Evaluation Module manual.
http://www.analog.com/media/en/technical-documentation/user-guides/UG-072.pdf


Then:
Learn by doing, the manual is a sort of *nudge* to get going, help files etc are useless, some info on functionality can also be dated and no longer relevant (probably not the case with ADAU1701).
It's not difficult to get the basics going, but there are just soooooooo many functions/features/algorithms/etc. if you want to do fancy stuff.

After you got the EVM manual, and have done the steps to figure out the basics there, click around a bit to get your signal routing going, then we can figure out the more advanced stuff together :)
 
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I have ADAU1467 eval board and I have also now designed my own board in kicad.

8 ch in, 16 ch out
spidf, bluetooth 5.0 module -> i2S
Raspberry interface as optional use, etc

see attached pics

i did run trough the examples in the eval board doc

i also have a mosconi 8to12 based on an older dsp in same family.
it was that one that inspired me to design my own.
 

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Very nice! Are you considering making some group buy or?
Not sure exactly what you mean.

I have pick and place machine and can manufacture thoose boards myself.

But maybe you refer to sell them?
If anyone wants them they are for sale.
Not my original plan, but sharing is a necessity especially to share the sw effort with the community.

Due to vacation no assembled pcba to be expected before late August.

And normally it's always a risk for something to be fixed in a completely new design.
 
I am very certain there is a lot of people that would be interested.
You should at the very least consider costs and what you would sell it for, most of us do not have access to automated production equipment.

Not many DSP setups that can do 8 channels x 2 way speakers.
And there is also a shortage of more than 4x out DSP kits to work with the Raspberry.

No worries about the time aspect, most here do other stuff in the summer.
 
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Ok.

Cost is a bit unclear but components alone probably mounts up to $100 range.

Also the wish list from the community is unclear.

I was now planning on adding MM/MC input as well.

Already is optiken to mount Bluetooth module.

What I want to follow up with later is class D amplifiers fed directly over I2S/TDM

Thats my goal to go digital all the way to the speaker element.

And have all elements individually boxed.
I would like to get out of the composite speaker mentality and into the single element mindset.

Updates will follow.
I am doing the USB to SPI interface now as that was fairly costly from analog device as an eval board.

Option to run both RPI3 as master or the PC
RPI3 can still control the codecs even in the case that PC control the DSP.
Selectable trough switches.

I also wonder how I can measure the THD and everything to make sure it really delivers top quality.
 
I do not know whether this translates to any new functionality or not.
But thank you :)

Regarding RPI pinout, does this help?
I2C at Raspberry Pi GPIO Pinout

and:
Raspberry Pi 2 & 3 Pin Mappings - Windows IoT | Microsoft Docs

The Raspberry Pi: Audio out through I2S | Dimdim's Blog

I do not understand completely what you are having difficulties with. Ref: your post #14

Edit:
Excerpt from Dimdim's page:
"So, the theory is sound and the RPi’s clock is not up to snuff by strict standards. What this means is that the RPi’s I2S output is not capable of “Hi End” audio transmission. It is essentially not bit perfect (edit: this is not correct, strictly speaking. It is in fact bit perfect, it is just not “proper”.).

In the real world, chances are that this problematic clocking will not be particularly audible under normal circumstances, say with a normal-specc’ed sound system. But an audiophile should definitely steer clear of the RPi’s I2S output, instead opting for a USB to I2S interface."
 
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I do not know whether this translates to any new functionality or not.
But thank you :)

Regarding RPI pinout, does this help?
I2C at Raspberry Pi GPIO Pinout

and:
Raspberry Pi 2 & 3 Pin Mappings - Windows IoT | Microsoft Docs

The Raspberry Pi: Audio out through I2S | Dimdim's Blog

I do not understand completely what you are having difficulties with. Ref: your post #14


never used i2s on rpi before did not even know it existed, so i did anticipate external circuitry.

as it is there native, the problem went away by itself :)
 
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