NAD M51 DAC high-pitched ringing?
Has anyone bothered to see what happens after 20khz to the M51,s FR? Very strange for a dac or cdp, looks like the resonance of early metal dome tweeters. Have a look at the second graph and look what happens after 20khz up to 100khz. Ultra sonic noise? could be upsetting the Jolida? http://www.stereophile.com/content/nad-m51-direct-digital-da-converter-measurements Cheers George |
"So it seems the DAC and the amp are functioning properly independently, but something screwy happens when they are used in conjunction. And the DAC is producing some signal doing its algorithmic thing that the Jolida is picking up on." "To Bill_K: When the DAC is used with a different amp (a pair of Audioengine 2 powered desktop speakers), the ringing stops. But when the Jolida is used from the headphone jack of the computer or from an ipod, there is no ringing either. So each component individually seems to work just fine, both the DAC and the Jolida seem healthy. But something about them working together makes bad mojo." I'm still not sure what the problem is, but reading those quotes made me think of a couple of other things you can try. First is a different music player. I assume you are using iTunes. Try Quodlibet for Mac. Its open source, so there's no charge for it. I can't say for sure, but you'll probably like it better anyway. It plays more formats and is a much better tagger than iTunes. Second is, how are you connecting your Mac to your dac? To get digital output, you an only do it 2 ways; usb or Toslink using a special adapter that plugs into your headphone jack. I'm assuming usb because its the most popular option, but a lot of people do use the Toslink option. And third, how do you connect your dac to your to the Jolida? This is really important because you have a balanced dac while the integrated is single ended. Even if you are going SE out on the M51 to SE in on the Jolida, you may have to do something to your M51 to make it work properly in SE mode. If you are using balanced cables and adaptors you still need to be very careful. Not all IC that have XLR connectors are balanced. Internally, the cables may be SE. There's a lot of confusion on this because when most people see IC's with XLR connectors, they automatically assume they're balanced. That's not always the case. It also wouldn't be a bad idea to call NAD. Its very possible that you're not the first person to have this problem. |
thanks for your responses guys, but I still haven't solved the problem. Moving the computer doesn't seem to affect anything. Everything's unplugged, changed, etc. When the laptop runs on battery, there is still ringing so I don't think laptop power source makes a difference. Played around with all the volumes, nothing there seems to make a difference. To Bill_K: When the DAC is used with a different amp (a pair of Audioengine 2 powered desktop speakers), the ringing stops. But when the Jolida is used from the headphone jack of the computer or from an ipod, there is no ringing either. So each component individually seems to work just fine, both the DAC and the Jolida seem healthy. But something about them working together makes bad mojo. |
Here's a few things you can try, but keep in mind, I'm just guessing as to what can be wrong. Try moving your computer further away from your other components. Turn off anything in the system that is not being used with you play music. If something is digital like another computer or source, unplug it. Don't just turn it off. I know you tried different outlets, but make sure you try plugging your computer into an outlet that's not on the same circuit as the rest of your system. You'll probably need to use an extension cord. Try going Toslink instead of usb to your dac. You'll probably need to get an adapter. They're cheap. Unplug all usb cords from your computer except for the dac. This may be some type of gain issue. Your music player software has a volume control, your OS has a volume control and your dac has a volume control, as well. Your dac may even have global gain settings (they may be internal).Play around with some different combinations and see if it effects the noise in any way. Try a different transport. Anything that has a digital out will work. A cheap cd/dvd player will be fine. Aside from that, I can't think of anything else. If I do, I'll post again. |
