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Problem with cd walkman and speakers

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someone

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Jun 14, 2012, 7:31:53 PM6/14/12
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I have a Sony portable CD player that I want to use indoors
for playing talking books. I don't want to use batteries
indoors if I can help it so I bought an AC adaptor to plug
the CD player into the mains. This all works fine, except
the portable speakers I had, also mains-powered, were too
tall and kept falling over.

Recently I bought a nice little mains-powered Altius
portable speaker from a local supermarket and it's only
about 8" long, and flat, so it doesn't fall over.

Now the strange problem: when playing a talking book, the
sound cuts out frequently for several seconds, always at the
same random point on the CD. I have pinpointed some of
these cut-out points and tried them again and again. I
assumed it was the CD player, so I bought another one
(stupid me). The sound still cuts out at the same point of
the CD on the new CD player, and the light flickers on the
Altius speaker.

I didn't have this problem with the larger speakers, but I
have traced it down to this: When I'm using the AC power
supply with the CD player, the sound cuts out. But if I
have batteries in the CD player, it doesn't. So I put a
couple of *dead batteries* in each of the two CD players,
and they work fine with the Altius speaker. But with no
batteries I get the cut-out problem with the CD.

Should I a) return the Altius speaker, b) put up with using
dead batteries in the CD player and hope I don't burn the
house down. I can't believe two different CD players can
have the same problem, so it's not down to them. I can't
figure out where the problem lies.

Any ideas would be appreciated.

someone


Brian Gaff

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Jun 15, 2012, 3:16:10 AM6/15/12
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Well before you said about the batteries, I was going to suggest a level
sensitivity. Presumably this player is playing mp3cds, but although the cd
does stop for periods during playing these, I cannot really see why starting
current would knock out the sound if the psu is also running the cd player.
Are there two supplies, does the cut out coincidew with the spopping and
starting of the cd?

Brian

--
--
From the sofa of Brian Gaff -
bri...@blueyonder.co.uk
Blind user, so no pictures please!
"someone" <som...@flibbernet.com> wrote in message
news:4fda7462$0$7310$5b6a...@news.zen.co.uk...

Dave W

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Jun 15, 2012, 4:49:57 PM6/15/12
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I Googled for Altius without success. I wondered if you meant Altus,
but they're Sony wireless speakers. So I assume your speaker is a
speaker with built-in mains-powered amplifier.

I suspect your Altius speaker has a lower input impedance than the
speakers that came with your CD player, e.g. 4 ohms instead of 8. So
your CD player takes too much current when a loud sound comes along,
starving its internal amplifier. Batteries can provide higher peak
current than the mains supply.

Does the Altius speaker have its own volume control? If so, you could
try turning this to max and turning down your CD player volume
control, so that the player doesn't have to put out so much power.

If the speaker impedance claimed for the Altius is lower than the
speaker impedance of the player then you've bought the wrong speaker,
but maybe you could get a refund.

Dave W

someone

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Jun 15, 2012, 6:31:52 PM6/15/12
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"someone" <som...@flibbernet.com> wrote in message
news:4fda7462$0$7310$5b6a...@news.zen.co.uk...
>I have a Sony portable CD player that I want to use indoors
>for playing talking books. I don't want to use batteries
>indoors if I can help it so I bought an AC adaptor to plug
>the CD player into the mains. This all works fine, except
>the portable speakers I had, also mains-powered, were too
>tall and kept falling over. etc., etc.

Thank you Brian and Dave for your replies. I know not a lot
about electrics/electronics, but here are the details of my
setup.

As I mentioned I mainly play talking books, and this player
(Sony D-EJ011) is playing files entitled track1.cda,
track2.cda and so on to track20.cda depending on the length
of the recording. There are usually about 10 CDs for a
talking book. There are two power supplies, one to power
the CD player and one to power the little speaker(s).

The spec for the CD player is:

DC 4.5V external DC supply, or battery 1.5V x 2.

I purchased an AC power adapter for this CD player, it is as
follows:

Input AC 100V-240V - 50/60 Hz
Output DC 5V 2A

Although it is Output 5V I was assured that it would work OK
with my CD player. And so it has, with the bigger awkward
falling-over speakers. But not with this little one.

The spec for the small speaker is:

5V 1A max
Output 2 X 2.5W
Switching adapter - power plug = Input 100-240V AC, 50/60 Hz
0.3 A max. Output = 5.0 V 500 mA
Frequency response: 100Hz=20kHz
Battery: 500mA, rechargeable

And it comes with a USB power connection cable which
connects to the mains plug with another smaller USB-looking
connector.

So, Brian, there are two mains power supplies, one for the
CD player and one for the speaker. However this is the same
as I had with my larger awkward speakers and they worked
fine. The cutout of the sound doesn't coincide with
anything at all except that it always happens at particular
points in the given CD.

And to Dave W.: the speaker is an Altius CP-0011 "portable
speaker with slimline design" bought from Aldi. It has the
specs mentioned above. Nowhere do they mention ohms, and I
don't know how to calculate them with this setup. I'll try
what you say re turning the Altius speaker to a higher
volume, and the CD player to low and see what happens.
Fortunately, I have two months within which to take the
speaker back if it is unsuitable or doesn't work, no
questions asked. I am amazed that batteries can provide
higher peak current than the mains supply.

Again, thank you for your interest in my problem and I will
check out what happens with turning down the CD player
volume.

Linda


NT

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Jun 15, 2012, 7:19:42 PM6/15/12
to
On Jun 15, 11:31 pm, "someone" <some...@flibbernet.com> wrote:
> "someone" <some...@flibbernet.com> wrote in message
>
> news:4fda7462$0$7310$5b6a...@news.zen.co.uk...
>
> >I have a Sony portable CD player that I want to use indoors
> >for playing talking books.  I don't want to use batteries
> >indoors if I can help it so I bought an AC adaptor to plug
> >the CD player into the mains.  This all works fine, except
> >the portable speakers I had, also mains-powered,  were too
> >tall and kept falling over.  etc., etc.
>
> Thank you Brian and Dave for your replies.  I know not a lot
> about electrics/electronics, but here are the details of my
> setup.

So far we know its speakers, not player

> As I mentioned I mainly play talking books, and this player
> (Sony D-EJ011) is playing files entitled track1.cda,
> track2.cda and so on to track20.cda depending on the length
> of the recording.  There are usually about 10 CDs for a
> talking book.  There are two power supplies, one to power
> the CD player and one to power the little speaker(s).
>
> The spec for the CD player is:
>
> DC 4.5V external DC supply, or battery 1.5V x 2.
>
> I purchased an AC power adapter for this CD player, it is as
> follows:
>
> Input AC 100V-240V - 50/60 Hz
> Output DC 5V 2A
>
> Although it is Output 5V I was assured that it would work OK
> with my CD player.

should be plenty for a portable player

> And so it has, with the bigger awkward
> falling-over speakers.  But not with this little one.
>
> The spec for the small speaker is:
>
> 5V 1A max
> Output 2 X 2.5W
> Switching adapter - power plug = Input 100-240V AC, 50/60 Hz
> 0.3 A max.  Output = 5.0 V 500 mA
> Frequency response:  100Hz=20kHz
> Battery:  500mA, rechargeable

So youre running an amp requiring 1A off an adaptor only able to
supply half that. No surprise it hits problems.

If the 2 supplies have the same polarity and connectors, evebrything
might or might not work if you simply swap them. If not, get a 1A or
more 5v supply for the speakers.


> And it comes with a USB power connection cable which
> connects to the mains plug with another smaller USB-looking
> connector.
>
> So, Brian, there are two mains power supplies, one for the
> CD player and one for the speaker.  However this is the same
> as I had with my larger awkward speakers and they worked
> fine.

new amp presumably has less efficient speakers or more bass response

>  The cutout of the sound doesn't coincide with
> anything at all except that it always happens at particular
> points in the given CD.

where sound output power is greatest

>
> And to Dave W.: the speaker is an Altius CP-0011 "portable
> speaker with slimline design" bought from Aldi.  It has the
> specs mentioned above.  Nowhere do they mention ohms, and I
> don't know how to calculate them with this setup.  I'll try
> what you say re turning the Altius speaker to a higher
> volume, and the CD player to low and see what happens.

wont make the least difference

> Fortunately, I have two months within which to take the
> speaker back if it is unsuitable or doesn't work, no
> questions asked.  I am amazed that batteries can provide
> higher peak current than the mains supply.
>
> Again, thank you for your interest in my problem and I will
> check out what happens with turning down the CD player
> volume.
>
> Linda

You should find turning down the speaker volume avoids cutting out.


NT

Dave Liquorice

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Jun 16, 2012, 4:16:07 AM6/16/12
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On Fri, 15 Jun 2012 23:31:52 +0100, someone wrote:

> The spec for the small speaker is:
>
> 5V 1A max
> Output 2 X 2.5W
> Switching adapter - power plug = Input 100-240V AC, 50/60 Hz
> 0.3 A max. Output = 5.0 V 500 mA

Discrepancy between the current requirement of the speaker and what
the PSU can supply. ie "1A max" and "0.3 A max". Curious that the PSU
rating is then followed by "5.0 V 500mA" that is 0.5 A. As this is a
switching PSU it might be shutting down on overload and then
automagically resetting. Is this the PSU that came with the speakers?
If it is take 'em back for a refund.

> The cutout of the sound doesn't coincide with anything at all except
> that it always happens at particular points in the given CD.

This is odd though the overload could be being caused by something
you can't hear (either because of your ears or the inability of the
speakers to reproduce it). The CD is clean and undamaged isn't it?

Do you have another audio source that you can test the speakers with
at high volume?

--
Cheers
Dave.



John Williamson

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Jun 16, 2012, 5:23:08 AM6/16/12
to
NT wrote:
> On Jun 15, 11:31 pm, "someone" <some...@flibbernet.com> wrote:
>> "someone" <some...@flibbernet.com> wrote in message
>> The cutout of the sound doesn't coincide with
>> anything at all except that it always happens at particular
>> points in the given CD.
>
> where sound output power is greatest
>
Or where there's a big enough defect on the CD surface to cause the
sound to mute.

Does the sound cut out at loud points on all CDs or only on this CD set
at particular locations?

As Dave says in his reply, have you checked the speakers at high output
on another CD, or with another source, such as a USB based mp3 player?


--
Tciao for Now!

John.

Dave W

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Jun 16, 2012, 7:53:39 AM6/16/12
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NT <meow...@care2.com> wrote:

>> I'll try
>> what you say re turning the Altius speaker to a higher
>> volume, and the CD player to low and see what happens.

>wont make the least difference

>NT

True, if it's the speaker at fault. I was thinking it was the player
cutting out due to overloading its output. It now looks like the fault
is just an inadequate power supply for the speaker, making its light
flicker as well.

Dave W

Dave W

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Jun 16, 2012, 5:37:15 PM6/16/12
to
I found out that your Sony player output is quoted as driving 16 ohm
headphones, but I can't find anything about the Aldi speaker input
except that it has an internal rechargeable battery which takes 3
hours to charge.

I take it that when the sound returns after cutting out, the speech
has not jumped back or forth, i.e. it's exactly as if the volume
control had been turned to zero for the cutout period? So there's no
question of the CD being upset?

My theory is that there is an inaudible low frequency thump from the
player which makes the speaker take too much current from its
inadequate power supply, but when you put batteries in the player,
somehow the thump is reduced enough not to overload the speaker.
It might be worth ensuring that the speaker has been powered up for 3
hours so that its internal battery will smooth over the deficiency of
the mains power supply that gives only half an amp instead of the
possible one amp peak required.

Another theory is that the player is too near the speaker, which then
vibrates the player and upsets the CD. When you put batteries in the
player the added weight holds it steady!

Dave W


someone

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Jun 22, 2012, 7:40:06 AM6/22/12
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"Dave Liquorice" <allsortsn...@howhill.co.uk> wrote in
message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
I've now tried everything that I can think of. I can only
conclude that the problem is somehow because I am using an
external power supply for the CD player, rather than
batteries. Strangely, the speakers work fine with my
desktop PC for things like BBC news and so on, and also if I
play a music or talking book CD on it.

I am admitting defeat, have re-setup my clunky speakers and
will take the Altius back to Aldi. There is really nothing
wrong with it in general, it's probably my configuration,
but I'm not enough of an electronics engineer to be able to
go any further.

Thank you all for your suggestions and help, I learned a
lot.

Linda


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