Portable CD player (Walkman-style) with good audio quality?

Discussion in 'rec.audio.pro' started by David Satz, Aug 26, 2003.

  1. I understand your complaint about the seemingly non-sequitur responses you
    received. It's just that for some of us, the question seemed so Utterly Weird
    that we wondered why it was being asked!

    I mentioned the following in another post, but it can't hurt to repeat it. My
    D-FJ75TR Discman -- which is _not_ a budget unit -- has a switch that shuts off
    the skip protection, primarily because the buffer and clocking circuitry draw a
    significant amount of current, reducing battery life.

    If a player has such a switch, you might reasonably assume it completely cuts
    off the buffering. But I don't know for sure.


    David Satz wrote...

    > William Sommerwerck wrote:


    >> You can't compress the disk's data until you get it and have it. And that
    >> "getting and having" are influenced by the player's skip resistance.
    >> Compressing it -- which raises the cost of the player for no good
    >> reason -- offers no advantage.


    > Hi, Bill. Your first statement is perfectly true, but the players I'm
    > talking about have two buffers "in series." The first buffer follows the
    > logic of every other CD player ever made, which is what you're defending
    > here. But once the usual anti-skip (relocating/splicing) logic has been
    > applied and the buffer is full of contiguous, uncompressed samples, its
    > contents are compressed and copied into a segment of a second buffer.


    > This allows the secondary buffer to hold many seconds' worth of audio.
    > The player magically acquires a new specification value, plus the amusing
    > ability to continue playing a track from RAM for some time after the disc
    > has been stopped or even removed from the player.


    > Such players have been around for several years now. I don't want to buy
    > one of those unless it's clear that the compression can be turned all the
    > way off.


    > --Folks, this thread is mimicking that well-known parody of R.A.P.; I asked
    > for specific information that I really need, and the 12 responses so far
    > have [a] extolled the virtues of HD players over CD players or else they've
    > argued about the existence or non-existence of data compression.
    > And oh, yes, there's been a bit of name-calling, or nearly so.


    > I don't want to diminish the interesting discussion, but strangely I would
    > _also_ really like to have some recommendations for a low-cost portable
    > CD player that is known to have relatively high-quality audio ... if possible.
  2. Chip Gallo

    Chip Gallo Guest

    Monroe wrote:
    > Check this link out. More than you will want to know and straight
    > discussion on new and old tech:
    >
    > http://www4.head-fi.org/forums/
    >
    > I'm pretty satisfied with a Panasonic model (SL-CT570); I believe it
    > is discontinued, but I see them popping up new every now and then.
    > Reasonable line out's, defeatable feature set. Nice.
    >
    > On 26 Aug 2003 14:58:17 -0700, DSatz@msn.com (David Satz) wrote:
    >
    >> This may seem slightly off-topic, or else not.
    >>
    >> I recently misplaced (!) the trusty old Sony Walkman CD player that
    >> I've used for the past 10+ years. Looking at the newer models, I see
    >> mostly units that offer powerful anti-skipping circuitry.
    >>
    >> Those circuits buffer the sample data in RAM, and the last I read,
    >> the Big New Thing was to use data compression on that data so as to
    >> tolerate nearly constant physical movement (jogging, etc.) without
    >> raising the cost of the hardware too much.
    >>
    >> I'd like to know whether anyone here can recommend a current-model,
    >> relatively inexpensive "Walkman"-style CD player that offers high
    >> quality audio outputs without that sort of data compression. Must
    >> be small, have a headphone output and be able to run on batteries.
    >> If there are any sonic special features such as "Mega Bass," they
    >> need to be fully defeatable.
    >>
    >> Many thanks.


    iRiver SlimX 350, available for $99 at Best Buy with a coupon.
    http://www.iriveramerica.com/products/iMP-350.asp

    That's what I listen to my rap cds on. (Smoked two Sonys in the last year so
    I'm off of them).

    Chip Gallo
  3. Mike Rivers

    Mike Rivers Guest

    In article <e6a68193.0308270556.2aeda6d1@posting.google.com> DSatz@msn.com writes:

    > --Folks, this thread is mimicking that well-known parody of R.A.P.; I asked
    > for specific information that I really need, and the 12 responses so far
    > have [a] extolled the virtues of HD players over CD players or else they've
    > argued about the existence or non-existence of data compression. And
    > oh, yes, there's been a bit of name-calling, or nearly so.


    To further get away from the subject header, it's quite possible that
    there's nobody here who actually knows what you're asking. It's not
    something that you'd find in advertising media, nor is the clerk at
    Circuit City likely to have a clue as to what you're talking about (a
    clever one who hears you say "compressed" might be sharp enough to say
    "Oh, yes, this will play a disk with MP3 files") but only a designer
    or repairman is likely to actually know what's inside the box. I don't
    think many designers of consumer electronics hang out here, and nobody
    fixes those things, even those who fix other things.

    So, I really don't know how you'd find out.



    --
    I'm really Mike Rivers - (mrivers@d-and-d.com)
  4. Mike Rivers

    Mike Rivers Guest

    In article <x393b.1177$Pj1.204@news02.roc.ny> cgallo@deleteThisCitlink.net writes:

    > >> I'd like to know whether anyone here can recommend a current-model,
    > >> relatively inexpensive "Walkman"-style CD player that offers high
    > >> quality audio outputs without that sort of data compression.


    > iRiver SlimX 350, available for $99 at Best Buy with a coupon.
    > http://www.iriveramerica.com/products/iMP-350.asp


    Do you know for sure that the anti-skip (16 minute!!!) doesn't involve
    data compression? And how do you know? This isn't commonly published
    information.

    And who the heck is iRiver? No relation to me, I hope?




    --
    I'm really Mike Rivers - (mrivers@d-and-d.com)
  5. Carey Carlan

    Carey Carlan Guest

    mrivers@d-and-d.com (Mike Rivers) wrote in news:znr1062022268k@trad:

    >
    > In article <x393b.1177$Pj1.204@news02.roc.ny>
    > cgallo@deleteThisCitlink.net writes:
    >
    >> >> I'd like to know whether anyone here can recommend a
    >> >> current-model, relatively inexpensive "Walkman"-style CD player
    >> >> that offers high quality audio outputs without that sort of data
    >> >> compression.

    >
    >> iRiver SlimX 350, available for $99 at Best Buy with a coupon.
    >> http://www.iriveramerica.com/products/iMP-350.asp

    >
    > Do you know for sure that the anti-skip (16 minute!!!) doesn't involve
    > data compression? And how do you know? This isn't commonly published
    > information.


    16 minutes at full CD quality is about 170meg of RAM.
  6. Arny Krueger

    Arny Krueger Guest

    "Carey Carlan" <gulfjoe@hotmail.com> wrote in message
    news:Xns93E4E7E2630B5gulfjoehotmailcom@207.69.154.206
    > mrivers@d-and-d.com (Mike Rivers) wrote in news:znr1062022268k@trad:
    >
    >>
    >> In article <x393b.1177$Pj1.204@news02.roc.ny>
    >> cgallo@deleteThisCitlink.net writes:
    >>
    >>>>> I'd like to know whether anyone here can recommend a
    >>>>> current-model, relatively inexpensive "Walkman"-style CD player
    >>>>> that offers high quality audio outputs without that sort of data
    >>>>> compression.


    >>> iRiver SlimX 350, available for $99 at Best Buy with a coupon.
    >>> http://www.iriveramerica.com/products/iMP-350.asp


    >> Do you know for sure that the anti-skip (16 minute!!!) doesn't
    >> involve data compression? And how do you know? This isn't commonly
    >> published information.


    > 16 minutes at full CD quality is about 170meg of RAM.


    You beat me to it!

    And the chances of a $100 CD player having a 170 megs of RAM this year is
    zero.

    However, this does look like a nice player on paper.
  7. Frank Vuotto

    Frank Vuotto Guest

    I have a Sony S2 D-SJ301 that I'm having a love/hate with. It's
    impossible to make it skip, I often use it as a tambourine on my
    morning walks. It's decently built and the sound is much better than
    any of the others I have tried.

    The hate part comes from the phones. The ones that come with it sound
    ok but I don't like the style. The problem is that I can't find
    replacements that work without occasional distortion (garble on one
    side). I think it's an impedance problem but I don't have hi-z phones
    to check it out.

    Anyhow, the carry them at WalWarts so you can check one out for a few
    days.


    Frank /~ http://newmex.com/f10
    @/
  8. cgallo@deleteThisCitlink.net writes:

    > iRiver SlimX 350, available for $99 at Best Buy with a coupon.
    > http://www.iriveramerica.com/products/iMP-350.asp


    mrivers@d-and-d.com (Mike Rivers) wrote:

    > Do you know for sure that the anti-skip (16 minute!!!) doesn't
    > involve data compression? And how do you know? This isn't commonly
    > published information.


    On Thu, 28 Aug 2003 at 02:45 -0000, Carey Carlan wrote:

    > 16 minutes at full CD quality is about 170meg of RAM.


    The player specification says "Skip-Free Playback up to 16 minutes".

    16 minutes of a 32kbps mp3 file needs about 4MB which is a likely
    amount of buffer memory. You probably only get 23 seconds of
    skip-free playback for real CD audio.

    On 26 Aug 2003 at 14:58:17 -0700 David Satz (original poster) wrote:

    > Those circuits buffer the sample data in RAM, and the last I read,
    > the Big New Thing was to use data compression on that data so as to
    > tolerate nearly constant physical movement (jogging, etc.) without
    > raising the cost of the hardware too much.


    I suppose its possible that some CD players would compress the CD data
    after being read in order to increase the skip-free time. I would
    rather suspect that "Big New Thing" is a user function of playing MP3
    data instead of Audio CD, and not additional functionality inside the
    player.

    Stuart
    --
    I've never been lost; I was once bewildered for three days, but never lost!
    -- Daniel Boone
  9. Chip Gallo

    Chip Gallo Guest

    Arny Krueger wrote:
    > "Carey Carlan" <gulfjoe@hotmail.com> wrote in message
    > news:Xns93E4E7E2630B5gulfjoehotmailcom@207.69.154.206
    >> mrivers@d-and-d.com (Mike Rivers) wrote in news:znr1062022268k@trad:
    >>
    >>>
    >>> In article <x393b.1177$Pj1.204@news02.roc.ny>
    >>> cgallo@deleteThisCitlink.net writes:
    >>>
    >>>>>> I'd like to know whether anyone here can recommend a
    >>>>>> current-model, relatively inexpensive "Walkman"-style CD player
    >>>>>> that offers high quality audio outputs without that sort of data
    >>>>>> compression.

    >
    >>>> iRiver SlimX 350, available for $99 at Best Buy with a coupon.
    >>>> http://www.iriveramerica.com/products/iMP-350.asp

    >
    >>> Do you know for sure that the anti-skip (16 minute!!!) doesn't
    >>> involve data compression? And how do you know? This isn't commonly
    >>> published information.

    >
    >> 16 minutes at full CD quality is about 170meg of RAM.

    >
    > You beat me to it!
    >
    > And the chances of a $100 CD player having a 170 megs of RAM this
    > year is zero.
    >
    > However, this does look like a nice player on paper.


    It sounds good through the headphone amp and Senn 280 headphones. Amp spec
    is stated to be 20-20KHz +/-2db. It plays mp3, wma and asf files and
    supports the WINAMP play list. You can flash the firmware as needed (update
    codecs). Downside is that the line out is affected by the eq so the output
    stage is more complicated than some engineers would like. I'll ask them
    about the anti-skip compression. You have a choice of 45 seconds (for
    maximum sound quality) or 180 seconds (maximum skip protection).

    Chip Gallo
  10. On Thu, 28 Aug 2003 at 15:00 -0000, Stuart Barkley wrote:

    > I suppose its possible that some CD players would compress the CD
    > data after being read in order to increase the skip-free time. I
    > would rather suspect that "Big New Thing" is a user function of
    > playing MP3 data instead of Audio CD, and not additional
    > functionality inside the player.


    Okay, I didn't read some of the deeply nested comments earlier in this
    thread. Apparently, there are some and possibly many CD players which
    do compress CD audio data when using skip-protection mode.

    See those other comments for some very good information.
  11. David Satz

    David Satz Guest

    Having started this thread, I'd like to report back to let the group know
    what I eventually came up with.

    It seems that Sony players do have the type of anti-skip buffering with
    data compression that I was concerned about, but it seems to be defeatable.
    In the models I saw, the switch for this function is beneath the lid of the
    player, on the "floor" of the disc transport itself. This capability is
    called "G-PROTECTION" so I guess where the control switch is located must
    logically be the player's "G-spot."

    The language in the owner's manual is fairly oblique:

    > The G-PROTECTION function has been developed to provide excellent
    > protection against sound skipping during many active uses. / When you
    > set the G-PROTECTION switch on your CD player to "2", the G-PROTECTION
    > function will be enhanced compared to "1." / To walk with the CD player
    > and enjoy high quality CD sound using the G-PROTECTION function, set
    > the G-PROTECTION switch to "1." When taking harder exercise, it is
    > recommended that you set it to "2."


    And the section about using the analog or digital line outputs says:

    > To record high quality CD sound, set the G-PROTECTION switch to "1."


    But I think that these hints are clear enough to be fairly conclusive.
    "1" and "2" are the only settings; there is no "off" or "0" setting.

    The model that I bought is the D-EJ855. As noted it has a digital output,
    plus it looks like a miniature flying saucer, which I think is important
    in this day and age. So far, every disc I've played on it has had the
    usual pure, perfect sound forever that we've all grown to love and expect
    from CDs.

    And I haven't lost this player yet, unlike the one it replaces. That's
    obviously a big improvement. So I'm pretty happy with this purchase.

    --best regards
  12. There are Sony players in which the G-Protection switch is "on" or "off" -- no 1
    or 2 multi-level jazz.

    > The G-PROTECTION function has been developed to provide excellent
    > protection against sound skipping during many active uses. / When you
    > set the G-PROTECTION switch on your CD player to "2", the G-PROTECTION
    > function will be enhanced compared to "1." / To walk with the CD player
    > and enjoy high quality CD sound using the G-PROTECTION function, set
    > the G-PROTECTION switch to "1." When taking harder exercise, it is
    > recommended that you set it to "2."
  13. Arny Krueger wrote:
    >
    > This begs the question, skip resistant under what kind of severe operational
    > conditions.
    >
    > Ultimately the CD player versus hard drive player skip resistance comparison
    > rests on how the pickup mechanisms are positioned. Optical pickups are
    > positioned by electro-optical servo mechanisms which have improved greatly,
    > but are still less shock resistant than hard drives. Hard drives use a far
    > simpler but more robust scheme based on the pickup assembly being supported
    > by a fluidic layer that is inherent in the higher-speed spinning of the
    > disk.


    Nicely put--and don't forget the nicity of having a sealed drive (and
    the possible ability to upgrade it later if you want.)




    > Because of the greater cost and energy use of hard disk players, they also
    > have larger cost and power budgets for implementing buffers. For example the
    > NJB3 uses a 16 megabyte buffer, while CD players seem to be generally
    > limited to 16 megabit buffers, or about 1/8 as much buffering. In MP3 mode
    > the 16 megabyte buffer of a NJB3 holds anywhere between 1 and 3 complete
    > songs. (!!!) In .wav mode, it holds about 90 seconds of uncompressed audio.


    AFAIK the new iPod uses a 32mb buffer (and what stellar industrial design!)

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