Crackle from RotelCD when music silent

[plateletboy]

Hi,

Please Help! I have a really specific problem on my Trichord Clock2 clocked Rotel RCD-965bx. When a CD is played there is a crackling/static like noise at the very beginning of a track before the music 'starts', as it were. However, when music is playing with a constant 'sound output' the CD player is perfectly normal. Similarly, if I play music with many 'silent' pieces, the crackle reappears - its worse with older pieces of music, particularly Pet Sounds by the beach boys (which i think was done on a four track?!?).

The crackle is independent of the loudness of a particular sound on a music track - its like as long as some note/noise is being sent from the disk the crackle is not there?!?

The best example of this is the very first track off pink floyds dark side of the moon - the heart beat. Its very crackly for the first five seconds of the track, but then completely goes away as the heatbeat fades in, even before I can actually hear the heart beat through the speakers?!?

I'm new to this and dont have that much fine electronics knowledge. I've checked obvious things like dry joints and am at a loss what to do next?!?

I really, really adore this player and dont want to replace it yet.

Any help or suggestions would be greatly appreciated

murray

[jean-paul]

I had it once with a cdplayer with a mounted low jitter clock. It turned out to be the ground connection of the clock. It disappeared when I added a separate supply that had ground only connected to the point it had to feed at the mainboard.

A groundloop with a newly fitted clock is almost inevitable. Try a battery for testing if it disappears.

Otherwise it could be the spindle motor that is near EOL ...

[EDUM]

Try a testdisc with fingerprints/scratches etc, f.i. a Philips testdisc 5A. Your player should be able to play it without problems. If the player quits or the sound gets audible worse the spindle motor can be EOL indeed.

Another posibility is a capacitor EOL in the audio circuit of the player or preamp.

Is the Pink Floyd CD a "special" one? I remember that there was something with that CD. But what?

Success!

Ward

[plateletboy]

Thanks both of you, that really helps.

Can I just use a little square 9v battery to test? If it is the ground connection do you have any suggestions as to where else I can get a ground that isnt likely to cause the noise?? If not will I have to get a separate power supply unit from trichord?

What do you mean by "a groundloop is inevitable with a new clock"? Surely it isnt something that will go away as the clock is 'run in'?

The player still sounds fine with very old scratched CDs so i hope the spindle motor is okay. Is it easy enough to get replacements for them if it did go?

many thanks

murray

[JohnW]

From your description of your problem, if your palyer is not mis-reading the discs, then I would suspect the TriChord clock modification. Have you tried to put your finger on the “Clock” line from the TriChord module – the extra capacitance of your body might help things, if the noises disappear or worsen – then it’s a sure indication of a poorly fitted (interfaced) upgrade.

If this is the case, then try reducing the length of the Clock and Ground leads – if this still does not help then try adding a 27 Ohm to 100 Ohm resister in series with the clock line – as close as possible to the Clock Module board.