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Old 23rd April 2014, 04:20 AM   #1951
tube-it is offline tube-it  United States
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I think I may have just killed the USB module on my Opus DAC by sending some AC into it (long story). I think this a good excuse to get the SPDIF module and toslink. My mac has optical out and would love to start taking advantage of the higher bit rate. Anybody have a good suggestion on where to start with testing this? what is designed to blow first?
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Old 8th May 2014, 05:22 AM   #1952
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Hi Russ, Brian,

I would like to connect my WaveIO to the Opus DAC but soon realized that I had to play with the OSR bit for 24/192 material... Setting the OSR switch to high rate will enable 24/192 material to be played but will effectively lose upsampling for lower resolution material, correct? If this is the case, then it is not really good alternative and I don't want to use a relay base solution.

Could I use the Metronome for this task? WaveIO I2S --> Metronome --> Opus I2S
I would like to upsample everything lower than 24/192 to 24/192 for the Opus DAC, this way I get to play all material properly.

If this would work, could you please let me know which DIP switch settings to change for both Metronome and Opus to accommodate this setup? I would do it but I'm not an expert when it comes to filters.

Thanks
Do
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Old 8th May 2014, 02:42 PM   #1953
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did you try listening to your Opus with the OSF in the high sample rate position and 44.1-96 kHz files? I put a simple three way switch on the front of my Opus so I could manually change the OSF rates, but I find I often like the sound of less oversampling, even on lower rate files. I know this approach is probably letting through more alias products, but I do not seem to be experiencing the "cloudy" sound I usually hear from NOS style DACs with busy music...
If your Wave IO has the NDK oscillators onboard, those become the master for the Opus when you connect it directly, and the NDK oscillators are really good-I am not sure I would want to add the extra processing of an asynchronous sample rate converter in my Opus.
I know what I am suggesting is not the "correct" way to do it, but it does not hurt to try listening with less oversampling first.
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Old 8th May 2014, 06:50 PM   #1954
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Quote:
Originally Posted by barrows View Post
did you try listening to your Opus with the OSF in the high sample rate position and 44.1-96 kHz files? I put a simple three way switch on the front of my Opus so I could manually change the OSF rates, but I find I often like the sound of less oversampling, even on lower rate files. I know this approach is probably letting through more alias products, but I do not seem to be experiencing the "cloudy" sound I usually hear from NOS style DACs with busy music...
If your Wave IO has the NDK oscillators onboard, those become the master for the Opus when you connect it directly, and the NDK oscillators are really good-I am not sure I would want to add the extra processing of an asynchronous sample rate converter in my Opus.
I know what I am suggesting is not the "correct" way to do it, but it does not hurt to try listening with less oversampling first.
Hi Barrows,

How did you connect the MCK with the WaveIO? I don't know if I have the NDK oscillators but they're so tiny it will take a magnifying glass to see the writing on them. Any other DIP settings you changed?

Thanks
Do
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Old 8th May 2014, 08:36 PM   #1955
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Quote:
Originally Posted by pinnocchio View Post
Hi Barrows,

How did you connect the MCK with the WaveIO? I don't know if I have the NDK oscillators but they're so tiny it will take a magnifying glass to see the writing on them. Any other DIP settings you changed?

Thanks
Do
Do not use the Wave IO, but I am sure Lucien must provide master clock out as part of the I2S feed?
I cannot remember my settings, I am using one of the minimum phase filter options. the manual in combination with the Wolfson 8741 data sheet has all the information you need to figure it out.
The NDKs are tiny, and marking is almost impossible to read... I know Lucien had mentioned he was shipping most boards with NDK oscillators. The Opus has to have a master clock feed to work, so if it is working you are providing a master clock from somewhere....
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Old 27th August 2014, 09:34 PM   #1956
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Default DSD, the 8741 Opus in the coming environment

As the Botic Cape seems to be approaching release testing, I would like to get some impressions about the reality of my plans. I have used an 8740 Opus since 2008 for PCM and have found it a fabulous device in my primary system, connected to the now way-out-of-date Squeezebox Classic. I am looking forward to the Botic Cape becoming my rendering client and hope to use it with an Opus 8741 for DSD. My first round of questions are:

1) Are there more Opus 8741 units in the offing? And, are they likely to be the mooted upgrade including trident regulators?

2) Would these units be capable of 128fs or even 256fs dsd depending, of course, on the software used?

3) If I were to send DSD only, would I leave out the Metronome I currently use and connect the I2S directly from the Botic Cape to the Opus DSD inputs?

I realize that many/most will connect the Cape to A Buffalo variant, but I have been so happy with the Opus that I thought it would be a good, less expensive, option at least in the beginning.

Thanks,

Skip
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Old 28th August 2014, 02:40 PM   #1957
miero is offline miero  Czech Republic
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Quote:
Originally Posted by Skip Pack View Post
2) Would these units be capable of 128fs or even 256fs dsd depending, of course, on the software used?
I think it is not possible to use generate anything larger than 64fs using BBB.

Quote:
The McASP transmitter supports serial formats of:
Slot (or Time slot) size = 8, 12, 16, 20, 24, 28, 32 bits.
Word size ≤ Slot size.
Two (for stereo) 32 bit slots is 64fs.
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Old 28th August 2014, 09:12 PM   #1958
miero is offline miero  Czech Republic
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Ah, sorry ... you were asking on DSD...

BBB is capable to generate DSD64 and DSD128.
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Old 29th August 2014, 04:51 PM   #1959
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Thanks Miero, had me worried there for a second.

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