I was playing a CD earlier today and there was a lot of scratchy sibilants. Somewhat like a REALLY badly aligned tonearm/cartridge but not exactly. I began to wonder how in the world a CDP would do that, or might it be the amp or something else. There are a lot of issues to consider so please bear with me. First, the CDP is an Oppo DV-980H that I got from the dump. Spindle motor was dead and with a replacement motor it worked well. But it has been out of the system as a backup for a while and I had never played this particular CD on this player before. In fact, haven't played this CD in a while anywhere.
CD is by Iris Dement (Infamous angel) and she has an odd (I find it interesting) voice which can have a bit of a whiny character. This is the only one of the 3 of hers I have that sounds this way. And when I tried the CD in a car CDP it sounded clean, no scratchy sibilants. So it's tempting to think it's something about the Oppo CDP. But there's more. When I first tried loading the CDP in the car, it failed to load. I had to re-insert it for it to load and read properly, so maybe there's an issue with the disc. Except that once it loaded it played just fine.
But wait, there's more. I very recently had a power issue when the neutral leg of our mains power line got severed. Here in the US homes typically get 240v delivered but they are split into 2 legs of 120v. The neutral acts like a grounded center for the 240, so without that reference, normally 120v outlets can run right up to the full 240v or thereabouts. There is a problem with at least one item in the house from this situation (we're still testing a few things); another CDP that was plugged in and on standby seems to be unable to power up after the incident. But this particular CDP was not plugged in so could not have been affected by the power issue. Most other things seem to have been OK. Now, during this power situation my amp (a DIY tube amp - a 13EM7 SE amp) was plugged in but not running. I'm guessing there could be an issue with IT, but as I said above, other discs including ones by the same artist with similar sibilants seem to play without issue.
I'm wondering a few things. First, could it be something about the CDP itself that would cause it to read this one disc oddly with scratchiness, or is that not possible (it's 1s and 0s after all...). Could there be a read issue that would cause this disc to read with scratchy sibliants (it DID have a load/read error in the car CDP after all, but then it also eventually played fine there)? Or is it more likely a capacitor in the amp might have been fried by the power issue in a way that makes it susceptible to scratchiness (but again, other similar CDs don't play with scratchiness...).
I'm a bit dumbfounded about what could be going on, so thank you a ton for any input on this.
CD is by Iris Dement (Infamous angel) and she has an odd (I find it interesting) voice which can have a bit of a whiny character. This is the only one of the 3 of hers I have that sounds this way. And when I tried the CD in a car CDP it sounded clean, no scratchy sibilants. So it's tempting to think it's something about the Oppo CDP. But there's more. When I first tried loading the CDP in the car, it failed to load. I had to re-insert it for it to load and read properly, so maybe there's an issue with the disc. Except that once it loaded it played just fine.
But wait, there's more. I very recently had a power issue when the neutral leg of our mains power line got severed. Here in the US homes typically get 240v delivered but they are split into 2 legs of 120v. The neutral acts like a grounded center for the 240, so without that reference, normally 120v outlets can run right up to the full 240v or thereabouts. There is a problem with at least one item in the house from this situation (we're still testing a few things); another CDP that was plugged in and on standby seems to be unable to power up after the incident. But this particular CDP was not plugged in so could not have been affected by the power issue. Most other things seem to have been OK. Now, during this power situation my amp (a DIY tube amp - a 13EM7 SE amp) was plugged in but not running. I'm guessing there could be an issue with IT, but as I said above, other discs including ones by the same artist with similar sibilants seem to play without issue.
I'm wondering a few things. First, could it be something about the CDP itself that would cause it to read this one disc oddly with scratchiness, or is that not possible (it's 1s and 0s after all...). Could there be a read issue that would cause this disc to read with scratchy sibliants (it DID have a load/read error in the car CDP after all, but then it also eventually played fine there)? Or is it more likely a capacitor in the amp might have been fried by the power issue in a way that makes it susceptible to scratchiness (but again, other similar CDs don't play with scratchiness...).
I'm a bit dumbfounded about what could be going on, so thank you a ton for any input on this.
What happens if you rip it with Exact Audio Copy (EAC), and have it lookup the checksum online? If the checksum is okay and the sound is still sibilant/overly-bright then the CD possibly could have been made with pre-emphasis.
To find out you could open the ripped wav file in Audacity or some other wav editor and try applying de-emphasis EQ. If that fixes it, you could save the new wav file then burn it back to CD.
To find out you could open the ripped wav file in Audacity or some other wav editor and try applying de-emphasis EQ. If that fixes it, you could save the new wav file then burn it back to CD.
Pre-emphasis was only widely used in Japan. Viewing the spectrum in Audacity would show you if there is something odd. Most music has a fairly smooth treble roll off
Update. I carefully cleaned the CD and played it. Possibly a little improvement but not much. Then I ran a "cleaning" CD which has little brushes which in theory wipe the lens as it spins). It has worked on some CDPs that won't play consistently. This seems to have cleaned up the scratchiness a bit, but it's still there. What I thought was scratchy sibilants, though, turns out to perhaps actually just be high dB output of higher frequencies. When louder high frequencies come along, that seems to be the trigger for the noise. I'll try to capture it and post. I'll eventually open it up and clean the laser lens with an appropriate cleaner. I've read Vodka but that would seem to leave a slight residue. So if you have suggestions of a readily available cleaner, I'd appreciate it.
Take an cotton swab with some saliva and gently clean the lens.
Turn it and polish, also gently.
Done.
