DAC: CS4398 with CS8416+CM102s

I forgot to mention one thing, if you build the output stage from the datasheet and skip the 22µF capacitor, 100k Ohm resistor and 560 Ohm resistor, you will have a DC offset of about 2,5V from your output. There is barely any space left on the PCB to even attach a small 22µF capacitor and a 100k resistor. The max. output swing is about 2V RMS.

If you use eg. a tube amplifier without a input capacitor, it will change your bias point. My tube amplifiers use input capacitors but I know that some guys rather like to skip those, for whatever reasons.

I´m very happy with the power section since I cannot see any ripple at all with my scope. No buzzing, no noise. It is already oversized, considering the fact that the small LME49720 barely drains any current.

In conclusion, this unit is quite cheap but still nice if you´re looking for something to play with ;) I use it every day and don´t need another DAC now..

Best regards,
 
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Thanks for the clarification.

I should correct my mistake in post #60. I referred to CS4016 a couple of times. I should have written CS8416, of course.

I am very much looking forward to this board arriving. I just received my new Donegan Optical OptiVisor, so I am ready to do some tinkering.
 
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One question; the data sheet specifies the 22uF output cap to be a polar electrolytic. Most people around here recommend against electrolytics in the signal path. Can any 22uF cap be used here, or is there a specific reason why a polar electrolytic must be used?
 
You can use a 22µF foil capacitor too if you can find one ( and ofc have enough space for it since a foil capacitor with this value will be huge ).

You can use a simple electrolytic capacitor too but you have to make sure that it can withstand the voltage. For low frequency applications a simple electrolytic capacitor is good enough.

Best regards,
 
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I will not be receiving mine, because my mail delivery idiot delivered it to the wrong house and the occupant of the house signed for the package and accepted it.

So now I have no board and no way to get my money back, since ebay abandoned me.

I won't be ordering another one, so I have to quit this project. Best of luck, zdr.
 
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No. Canada Post claims that they are under agreement with China Post to not initiate traces on packages. A trace must be initiated from China, buy the vendor. The vendor refuses to provide assistance because the package was "delivered" and ebay is siding with the vendor.

Therefore, I am f&cked.

This is one of 4 packages that were not delivered to me in the past few weeks, totalling over $200 worth of merchandise. Either the postal idiot is a thief, or the recipient is a thief. Either way, the police do not care.

What a wonderful world we live in. No recourse. No accountability. It is rampant, and I blame the Unions.

I will not be using ebay any more, and I will have all of my packages sent to me via DHL or UPS, regardless of the cost.
 
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A miracle occurred!

I received my board, despite the fact that it was delivered to, and signed by, some random stranger - 2 weeks ago. Apparently, the random stranger opened it and decided it wasn't something they would like to keep. So they put it in my mail box. We live in a strange world, folks.

It'll be a while before I get around to doing anything with it. In the meantime I think I will e-mail LJM and ask if there is a BOM. I likely won't use many of the components, but it would be a starting point.
 

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CS8416 CS4398 DAC Kit Support USB

The schematics are rong the supply for +5v and +3.3v-2 are withdrawn from +7812.
And we can give a new power supply to the CS4398 (+3.3v) by adding one LP2950-3.3V as y show on the shcematics.
 

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I have just noticed that there are (at least) two different versions of this board.

On one version, the i2s signals from the CS8416 to the CS4398 go through a series of resistors. On the other version (which I have, and so does prusony - according to his schematic) the i2s signals go through a 74HC157D muxer.

This is rather a disappointment for me, as I was planning on feeding the CS4398 i2s signals directly from a CM6631A board, and I was planning on using those resistor holes to create an i2S input header on the CS4398 board.

I have decided to just use the SPDIF input on the board via CS8416, and I have populated the board with all necessary components except for the main power supply caps, voltage regulators, and the entire output filter. I plan to use some higher quality drop-in replacements for the LM7xxx VRs and I will build the output filter based on the CS4398 datasheet.
 
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It works!

I am quite enjoying the sound of this DAC so far. Running it with 2x LME49710 in a dual to single adapter.

Better detail and more refined than my ES9023 i2s DAC. I have not done an A/B comparison with my WM8740 DAC yet.

I am not sure if I will bother messing with it, except to put it in a chassis. For a total cost, including transformer, of $52 I am very, very happy!