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Old 26th August 2011, 06:33 AM   #1561
glt is offline glt  United States
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Not quite. They define the absolute phase if used in their default value. But changing some of the dacs will result in undocumented behavior.
(edit) I read your description again. I think it sounds right.
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Last edited by glt; 26th August 2011 at 06:47 AM.
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Old 26th August 2011, 07:01 AM   #1562
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Glt,

I saw the last version of your code. I made the modifications to use it in dual mono, added the fumction to use selectmode with the remote and the master trim.

Question: what is the story about the de-emphasis? I don't remember TP, but it looks like you disable that. I don't knowuch on the matter, but from what I read on internet, shouln't it be emabled? It appears in two different register values.

Thanks,

Davide
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Old 26th August 2011, 12:05 PM   #1563
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The DACB phase registers are relative to the DAC phase of each DAC. They are not absolute.

De-emphasis on the ES9018 is handled automatically if the SPDIF decoder detects that the signal has emphasis. Very few CDs are encoded this way. We just leave this as default since it is only turned on by the DAC when it is needed. Which is truly rare.
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Old 26th August 2011, 03:08 PM   #1564
glt is offline glt  United States
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Thanks Russ and Davide for sharing the info.

I don't think I would have figured it out through experimentation in a million years.

I might add that the remapping behavior also happens when you reduce the number of (digital parts) dacs due to increasing the quantizer bit size.

Experiment: Consider the even dacs. Use 8-bit quantizer (this turns off 2 or the 4 even dacs). If you flip the phase on all the even dacs, you get silence.

This may be a detail for BIII users in dual mono: Use 6-bit or 7-bit and no source remap (and all 4 dacs have the phase flipped) Switch to 8-bit or 9-bit and then you get silence...

Another observation: if DACXB is in relation to DACX, in what situation would you use DACXB in-phase with DACX?
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Old 26th August 2011, 05:26 PM   #1565
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glt some of what you are seeing is because of the physical connections as much as the internal remapping.

You should get a B3 so you can play around in earnest.
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Old 26th August 2011, 08:41 PM   #1566
glt is offline glt  United States
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Quote:
Originally Posted by Russ White View Post
glt some of what you are seeing is because of the physical connections as much as the internal remapping.

You should get a B3 so you can play around in earnest.
In due time, in due time
Right now is more fun dealing with the limitations of BII
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Old 26th August 2011, 11:28 PM   #1567
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Another observation: if DACXB is in relation to DACX, in what situation would you use DACXB in-phase with DACX?
Guess if you want to turn the chip on a SE output.

D.
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Old 30th August 2011, 02:22 PM   #1568
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I want to change my BII 80MHz clock for the new 100MHz clok to avoid drop-outs, it's easy to change? wich 100MHz clock will be plug & play, another Crystek? TP sells separately only the new clock for BII users?
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Old 30th August 2011, 02:40 PM   #1569
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You want the Crystek CCHD950-25-100, available from Mouser.

CCHD-950-25-100.000 Crystek Corporation Standard Clock Oscillators

We have them build by Crystek in batches but the quantities are aligned with the DACs we need to build, so we don't have extras floating around. When I prototype, I buy a few from Mouser.

As for ease of replacement, that really depends on the tools and skills available to you. I would typically use a hot-air rework station. Since it doesn't have pins, it's almost impossible to remove with an iron, unless you want to dissect the XO and systematically cut it up (destroy it).
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Old 30th August 2011, 03:03 PM   #1570
glt is offline glt  United States
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Originally Posted by Nikon1975 View Post
Guess if you want to turn the chip on a SE output.

D.
You are right. Datasheet says that feature is to allow all the DACs to be summed, for example to drive (directly in voltage mode) an amplifier...
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