Distortion with Ultra line out to B&K power amp

The Rotel spec indicates the output is 0.5 volts peak to peak which I believe was pretty standard fo CD players of it's vintage (2001). I did lower the line-in level to -10db but it did not make a difference.
That sounds very low for a CD player. Are you sure? Which Rotel model is it?
 
The Rotel spec indicates the output is 0.5 volts peak to peak which I believe was pretty standard fo CD players of it's vintage (2001).
0.5 V peak to peak is equivalent to 177 mVrms. That would be very, very low for every CD player ever made. Even the Philips CD100 had an output voltage of 2 Vrms for 0 dBFS.

But I think you could already rule out too high a voltage, so this might be of academic interest.
 
I've created a feedback ticket for Wiim and included the logs from my Ultra. I'll wait for their response before trying a reset or deleting and reinstalling the app.

I appreciate all the responses and will update the thread when new information is available.
 
Update!

I have no explanation for this but now without any further action on my part the Ultra is playing CD's just fine from the Rotel. I did a test yesterday with one of the most offending Telarc CD's and there was some minor distortion issues on big transients but no where near as before. I let it continue to play and after 15 minutes or so the distortion was completely gone. I've been testing again today and it seems to play fine.

This has me scratching my head and a bit uneasy with the setup. I have about a week left on my return/exchange window and don't want to be stuck with a device that might start acting up again down the road. For this reason I have it playing now for several hours and will continue to do so over the next several days. BTW Wiim just got back to me with a relatively cryptic reply to turn off EQ and if that doesn't work then perform a factory reset. I explained to them in my original message that the EQ was turned off.

I don't see how this could be a firmware issue but possibly a component related to the line-in connections. Firmware is what it is and I don't believe it can correct itself unless there is some learning function that figured out the problem and corrected it but that's maybe too AI for this situation.

I today received a Prozor coax to optical converter ($20 on Amazon) that I will try with the Rotel CD player. The Rotel only has RCA line out and an RCA coax, no optical. I'll try bypassing the DAC in the Rotel and use the Ultra's and see what I get.
 
BTW Wiim just got back to me with a relatively cryptic reply to turn off EQ and if that doesn't work then perform a factory reset. I explained to them in my original message that the EQ was turned off.
It's not all that cryptic if you take into account that EQ (just as well as pre-gain) could introduce digital clipping (after the Ultra's ADC), but from your description this doesn't seem to be the root cause.

The case remains somewhat spooky.
 
It's not all that cryptic if you take into account that EQ (just as well as pre-gain) could introduce digital clipping (after the Ultra's ADC), but from your description this doesn't seem to be the root cause.

The case remains somewhat spooky.
I realize that but the "cryptic" comment relates to only the EQ and a reset being mentioned and I had said in my original ticket that I was experiencing the problem with EQ turned off.

Maybe naive on my part but after a detailed explanation along with including the device logs I was hoping for something more insightful.
 
Today the distortion has returned and it's persistent through both the B&K power amp to the main speakers and the Wiim Amp Pro to the in-walls so not an issue with the B&K.

The coax/optical converter arrived yesterday and I just made the connections. The Rotel CD plays perfectly through the optical with the same program material and settings so this is obviously a problem with the Ultra's line-in circuitry.

I've been resisting the reset since it played fine yesterday but I apparently now have no choice. I don't see though how this could be firmware if one day it works and the next it doesn't. My guess is a line-in board component but what do I know.
 
Hi, reading this thread I miss the determination what could be the bad actor here.
If you would test all hardware invloved you can find out if it is a software problem or hardware.
So I would:
- Replace CD player with another CD device on the same digital cable. If you still get the noise/distortion;
- Find out if the cable is not shielding enough. first try another cable. If that does not solve it, place all device in another room to be sure there is no interference from other sources on the cable (this could be anything that sents signals around the room including WIFI, Powersupplies, Dimming equipment for your lighting), This could have an effect on the CD player too, less on the Wiim though.
- If nothing helps, the problem probably is with the CD digital output which is clocked on 48Khz/16 so then set the Wiim accordingly. There is no upgrade anyway in quality in setting this setting higher to the source .

My guess: Cable or CD digital output not stabile or very sensitive for interference. In it's own DA conversion it will probably be corrected.
Good luck!
 
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Hi, reading this thread I miss the determination what could be the bad actor here.
If you would test all hardware invloved you can find out if it is a software problem or hardware.
So I would:
- Replace CD player with another CD device on the same digital cable. If you still get the noise/distortion;
- Find out if the cable is not shielding enough. first try another cable. If that does not solve it, place all device in another room to be sure there is no interference from other sources on the cable (this could be anything that sents signals around the room including WIFI, Powersupplies, Dimming equipment for your lighting), This could have an effect on the CD player too, less on the Wiim though.
- If nothing helps, the problem probably is with the CD digital output which is clocked on 48Khz/16 so then set the Wiim accordingly. There is no upgrade anyway in quality in setting this setting higher to the source .

My guess: Cable or CD digital output not stabile or very sensitive for interference. In it's own DA conversion it will probably be corrected.
Good luck!
Thanks,

I did a factory reset yesterday and afterward the distortion was gone but the sound output was intermittent with frequent drop outs. I then power cycled the Ultra and it played OK for a short test but it did have one audio drop out initially but I need to test longer. Even when the Ultra was functioning without distortion it would drop out audio momentarily once when first playing a CD. Not sure if this is normal or a fault. It's been factory reset, has the latest firmware and has been power cycled so if it continues to act up I think I will exchange it. The Ultra plays without distortion when the CD player coax digital out is connected to the Ultra's optical in via a $20 converter which indicates to me there is something amiss with the line-in circuitry on the Ultra.
 
Hi,

Reading your post, it seems something with the reading or sending of a complete digital signal seems to happen.
Actually, this might also have to do when a CD laser is not reading great(old or dirty) or even the constant of the speed of the player. The (facory designed) fault correction in the CD player could be still able to handle these errors to the analog output.. but a digital signal can become 'incomplete' and missing bits leaving 'blanks' going through the DA chip in the Wiim towards the output.

I dont really understand your 20$ converter. Do you mean DA converter?

Could you set the Wiim on 48/16 to test
And to be sure.. test with a second CD player and cable if you can... ;) just to rule out the hardware.

Best!
 
The converter is a digital coax to optical due to the Rotel CD player not having an optical out.

I'v e tried several different sampling settings with no difference.

The problem is with the line-out of the CD player to the Wiim. The digital coax-out from the CD player through the converter to the optical-in on the Wiim seems to work fine. The CD player line-out works perfectly when connected to an analogue preamp. I think I've narrowed this down to the line-in circuitry on the Wiim but who knows. I'm also not comfortable with this being an intermittent issue where one time it plays fine and the next it's distorted but only on the biggest transients. I also am suspicious of the total audio drop out when first playing a CD through the line-in on the Wiim.

Thanks for your thoughts but I've decided to request a replacement as I've lost confidence in this unit as I've never heard or read of these issues in any reviews and I've performed the recommended fix by Wiim support with no resolution.
 
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