Connect with us

cdp distorts with cd-r, transport perfect

Discussion in 'Electronic Repair' started by [email protected], Apr 13, 2005.

Scroll to continue with content
  1. Guest

    Hi all,
    I have an Onkyo dx-6750 integra cd player, which I purcased as
    defective. I cleaned it and set it up with an oscilloscope, the
    transport is perfect now. Nice eye pattern, nice TE and FE signals,
    seeks fast, no skipping, no problems at all, nice sound - but with
    original cds only. When I try to play a cd-r disc, the transport still
    reads perfectly but the sound is distorted. If I take a look at the
    audio signal with the scope I see a somewhat "stepped" signal.
    Now, I just can't see if it's the transport or the digital circuits
    causing the problem. It's unlikely the transport because there are no
    signs of any difficulties with reading the data. And it's unlikely the
    digital circuits because once the data is read off of the disc I can't
    see how the rest of the circuits can make difference between different
    Any ideas?
  2. Sometimes it makes a difference what speed the CD-R was recorded at. (12X,
    24X, etc) You could try CD-R's which were recorded at a lower speed and see
    if that makes a difference.

    I have found this to be especially true of players which are Philips based.
    Since your model is not listed in my American Onkyo servicers' website, I am
    unable to examine the technical data.

    Mark Z.
  3. P.S.

    There are some "silver" CD-R's you could try.

    There may not be anything you can do to get it to play your existing CD-R's.

    Mark Z.
  4. m127

    m127 Guest

    Oh I see! I just thought that if it had a serious problem with those
    discs it would not play them at all but mute or stop. The
    unbelieveable thing was that it played, but distorted.
    Anyway, I have a nice little bunch of cd-players, some good ones also,
    like a Teac VRDS-10SE, a Teac CD-5, a better Onkyo (DX-6870), two
    Denons (dcd-755 and 1450), a B&O Beogram etc, so this Onkyo DX-6750 is
    to be for sale soon anyway. I just wondered if I could do anything to
    make it better and to sell it better. :)

    Another good idea is to keep it as a parts backup for my DX-6870 since
    the mechanical parts are the same.
    The interesting thin is that the 6870 doesn't have the problem the
    6750 has. They have the same transport. I still find it a very
    interesting question if the transport or other parts are the origin of
    the cd-r distortion problem.
  5. Mark

    Mark Guest

    try recording a cdr with another computer

    could be the sampling freq on the sound card in your pc or the servo
    speed on your cd burner is just a little out of range for the player

    did you try tweaking the FE and TE loops when the CD-R is playing?

  6. m127

    m127 Guest

    Hi Mark,

    Yes, I tried playing with Focus and Tracking, using a scope and
    listening to the sound. I didn't manage to take out the distortion,
    and now the servos are set at the best possible.
    I think my writer is OK, it's a very good plextor, writes crazy good
    discs that can be played on anything all over the world. I also played
    some discs written by others, and the distortion is still there.
    Anyway, I want to sell this player sooner or later, so it's not my
    discs that are the problem, I just wanted the player to be able to
    play more discs than it plays now.
    Someone somewhere told me that the origin of the problem can be the
    error correction, he said the player may have c2 errors with cd-r and
    leaves out some samples while playing back. Well, I don't know. I'm
    not that good in error correction and cannot monitor how many errors
    the player has got (and if it differs with different discs).
  7. Mark

    Mark Guest

    try asking on
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day