Add a DAC to a cheap CD player?
 

It's a comparative thing. The DAC on my DAB tuner (Sony STD777es)
sounds
inferior then when compared with the sound whilst connected through the
DAC
of the Arcam Black Box 500. I would assume that lesser DAB tuners would
also
benefit in this manner. Yes the bitrate of the transmission has a large
bearing on the sound, but then so does the DAC. When I buy a new
Freeview
box with digital output next month I should benefit from the superior
bitrates seemingly available via this platform with some broadcasts.

Yes better, but NICAM and FM still sound better.....

Not really relevant though. No UK radio transmissions employ NICAM (do they
elsewhere?) whilst the radio services offered via Freeview aren't available
on FM.

Now say 100 times:
"My dapper Dad's damn DAB DAC doesn't do DAT justice."

Didn't hear you saying it :o)

Add a DAC to a cheap CD player?
 

I would agree, although I'm not sure how that would be done - isn't that
just a natural result of better fidelity?

I have two freeview boxes, A Pioneer and a Sony. They work equally well in
most the time but the Sony cuts in and out during heavy rain and when I
turn the lights on.

My point is, with digital better fidelity means better at recovering data.
If high-end dacs were good at this they would find it harder to justify
ridiculous CD transport prices.

--
Jim H jh
@333
.org

Add a DAC to a cheap CD player?
 

I would agree, although I'm not sure how that would be done - isn't that
just a natural result of better fidelity?

I have two freeview boxes, A Pioneer and a Sony. They work equally well in
most the time but the Sony cuts in and out during heavy rain and when I
turn the lights on.

My point is, with digital better fidelity means better at recovering data.
If high-end dacs were good at this they would find it harder to justify
ridiculous CD transport prices.

--
Jim H jh
@333
.org

Add a DAC to a cheap CD player?
 

"Wally" wrote in message
...
A mate brought his Arcam CD player (8 or 9, I think) round for a listen
last
night, and (as expected) it showed up my cheapie Schneider DVD/CD
wossname.
Much better clarity and definition, I thought. The bass especially was a
huge improvement.

Then I realised that the Schneider has digital outputs - coax and
optical -
and wondered if it's feasible to connect a DAC to these and maybe approach
the sort of sound produced by the Arcam. A quick look in eBay indicates
that
there's a fair selection up to about £200.

Is this worth considering, or will the transport in the Schneider have a
deletrious effect in spite of whatever improvements a DAC wold bring? It
strikes me that the cheapest DVD/CD drive can deliver error-free digital
data to a computer, so one would think that a cheap transport in a CD
player
is capable of similar. If it is worth considering, what makes/models of
DAC
should I look at that would match the Arcam's level of fidelity?

Hi Wally,
Ok this is with my setup and my ears at the time and as with everything
YMMV.
I thought I'd try the same thing a while back with a DVD player as
RicherSounds were selling the Cambridge Audio Isomagic DAC for £70 (it
doubles up as an isolation platform). I didn't have the space for separate
CD and DVD players so the DAC route looked ideal.
When I hooked it up to the DVD player the difference was like night and day.
When I first bought the DVD player I thought the sound was ok it just lacked
a bit of weight and power, I messed around with bigger speakers and amps but
the it still sounded a bit weak and distant. As soon as I adding the DAC it
sounded like the speakers were being driven by a larger amp, the sound had
much more weight and I could actually hear the bassline.
I've since got a dedicated HiFi cd/amp but I've still got the DAC to hook up
to my second system.
As you can probably tell I was pretty chuffed with the change it made to my
system and I don't think that it was a top of the line product.
Ideally you should always audition before you buy and just because I had a
good experience with an offboard DAC it might not be the same with your
combination of equipment.
BTW my DVD player was/is a Sony 725.

HTH

Dave


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.542 / Virus Database: 336 - Release Date: 18/11/2003

Add a DAC to a cheap CD player?
 

"Wally" wrote in message
...
A mate brought his Arcam CD player (8 or 9, I think) round for a listen
last
night, and (as expected) it showed up my cheapie Schneider DVD/CD
wossname.
Much better clarity and definition, I thought. The bass especially was a
huge improvement.

Then I realised that the Schneider has digital outputs - coax and
optical -
and wondered if it's feasible to connect a DAC to these and maybe approach
the sort of sound produced by the Arcam. A quick look in eBay indicates
that
there's a fair selection up to about £200.

Is this worth considering, or will the transport in the Schneider have a
deletrious effect in spite of whatever improvements a DAC wold bring? It
strikes me that the cheapest DVD/CD drive can deliver error-free digital
data to a computer, so one would think that a cheap transport in a CD
player
is capable of similar. If it is worth considering, what makes/models of
DAC
should I look at that would match the Arcam's level of fidelity?

Hi Wally,
Ok this is with my setup and my ears at the time and as with everything
YMMV.
I thought I'd try the same thing a while back with a DVD player as
RicherSounds were selling the Cambridge Audio Isomagic DAC for £70 (it
doubles up as an isolation platform). I didn't have the space for separate
CD and DVD players so the DAC route looked ideal.
When I hooked it up to the DVD player the difference was like night and day.
When I first bought the DVD player I thought the sound was ok it just lacked
a bit of weight and power, I messed around with bigger speakers and amps but
the it still sounded a bit weak and distant. As soon as I adding the DAC it
sounded like the speakers were being driven by a larger amp, the sound had
much more weight and I could actually hear the bassline.
I've since got a dedicated HiFi cd/amp but I've still got the DAC to hook up
to my second system.
As you can probably tell I was pretty chuffed with the change it made to my
system and I don't think that it was a top of the line product.
Ideally you should always audition before you buy and just because I had a
good experience with an offboard DAC it might not be the same with your
combination of equipment.
BTW my DVD player was/is a Sony 725.

HTH

Dave


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.542 / Virus Database: 336 - Release Date: 18/11/2003

Add a DAC to a cheap CD player?
 

In article , Wally
writes
Jim H wrote:

How good, or not, is DAB through the external DAC?

The limiting factor is usually bitrate, not the DAC, so still worse
than FM.

Audibly, what differences are there between DAB and FM? I'm not a critical
FM listener (mainly because my tuner isn't exciting), so I'm wondering how
DAB would fare for background stuff.



Well on DAB the broadcasters have the opportunity to alter the
transmitted bit rates. "Quality" supposedly indistinguishable from CD
was reckoned to come in at 256 kilobits, but for most stations they have
now settled on 128 K/Bits (sometimes less and mono!) in order to pack
more channels in. Radio 3 is an exception at 192 K/bits. Most of the
128 K stations sound quite dire especially when "audio processing" is
applied in order to make them sound louder.

FM whilst not perfect uses a higher bit rate feed, NICAM 728 or a
version of it to feed the FM modulator which gives a higher quality of
audio assuming a good tuner and FM signal.


www.digitalradiotech.co.uk

has a lot of info of what's wrong with DAB in the UK:-((
--
Tony Sayer

Add a DAC to a cheap CD player?
 

In article , Wally
writes
Jim H wrote:

How good, or not, is DAB through the external DAC?

The limiting factor is usually bitrate, not the DAC, so still worse
than FM.

Audibly, what differences are there between DAB and FM? I'm not a critical
FM listener (mainly because my tuner isn't exciting), so I'm wondering how
DAB would fare for background stuff.



Well on DAB the broadcasters have the opportunity to alter the
transmitted bit rates. "Quality" supposedly indistinguishable from CD
was reckoned to come in at 256 kilobits, but for most stations they have
now settled on 128 K/Bits (sometimes less and mono!) in order to pack
more channels in. Radio 3 is an exception at 192 K/bits. Most of the
128 K stations sound quite dire especially when "audio processing" is
applied in order to make them sound louder.

FM whilst not perfect uses a higher bit rate feed, NICAM 728 or a
version of it to feed the FM modulator which gives a higher quality of
audio assuming a good tuner and FM signal.


www.digitalradiotech.co.uk

has a lot of info of what's wrong with DAB in the UK:-((
--
Tony Sayer

Add a DAC to a cheap CD player?
 

In article , just me
writes
It's a comparative thing. The DAC on my DAB tuner (Sony STD777es)
sounds
inferior then when compared with the sound whilst connected through the
DAC
of the Arcam Black Box 500. I would assume that lesser DAB tuners would
also
benefit in this manner. Yes the bitrate of the transmission has a large
bearing on the sound, but then so does the DAC. When I buy a new
Freeview
box with digital output next month I should benefit from the superior
bitrates seemingly available via this platform with some broadcasts.

Yes better, but NICAM and FM still sound better.....

Not really relevant though. No UK radio transmissions employ NICAM (do they
elsewhere?) whilst the radio services offered via Freeview aren't available
on FM.

NICAM is used to feed the main FM transmitters in the UK well BBC ones.

The extra radio channels on freeview are not available on FM as you
rightly point out. However freeview does use higher transmission rates
then T-DAB..

--
Tony Sayer

Add a DAC to a cheap CD player?
 

In article , just me
writes
It's a comparative thing. The DAC on my DAB tuner (Sony STD777es)
sounds
inferior then when compared with the sound whilst connected through the
DAC
of the Arcam Black Box 500. I would assume that lesser DAB tuners would
also
benefit in this manner. Yes the bitrate of the transmission has a large
bearing on the sound, but then so does the DAC. When I buy a new
Freeview
box with digital output next month I should benefit from the superior
bitrates seemingly available via this platform with some broadcasts.

Yes better, but NICAM and FM still sound better.....

Not really relevant though. No UK radio transmissions employ NICAM (do they
elsewhere?) whilst the radio services offered via Freeview aren't available
on FM.

NICAM is used to feed the main FM transmitters in the UK well BBC ones.

The extra radio channels on freeview are not available on FM as you
rightly point out. However freeview does use higher transmission rates
then T-DAB..

--
Tony Sayer

Add a DAC to a cheap CD player?
 

In article , Jim H
writes

I would agree, although I'm not sure how that would be done - isn't that
just a natural result of better fidelity?

I have two freeview boxes, A Pioneer and a Sony. They work equally well in
most the time but the Sony cuts in and out during heavy rain and when I
turn the lights on.

That's almost certainly due to a marginal aerial signal. Almost without
exception the DTV signals are transmitted over a much wider channel
range that the original TV channel plan.

Also the cable that you use as a down lead is likely to be the older
low-loss type more modern ones such as CT100 are far better...

My point is, with digital better fidelity means better at recovering data.
If high-end dacs were good at this they would find it harder to justify
ridiculous CD transport prices.


--
Tony Sayer

Add a DAC to a cheap CD player?
 

In article , Jim H
writes

I would agree, although I'm not sure how that would be done - isn't that
just a natural result of better fidelity?

I have two freeview boxes, A Pioneer and a Sony. They work equally well in
most the time but the Sony cuts in and out during heavy rain and when I
turn the lights on.

That's almost certainly due to a marginal aerial signal. Almost without
exception the DTV signals are transmitted over a much wider channel
range that the original TV channel plan.

Also the cable that you use as a down lead is likely to be the older
low-loss type more modern ones such as CT100 are far better...

My point is, with digital better fidelity means better at recovering data.
If high-end dacs were good at this they would find it harder to justify
ridiculous CD transport prices.


--
Tony Sayer

Add a DAC to a cheap CD player?
 

Stewart Pinkerton wrote:

Not 'necessary', but it does help an outboard DAC to approach the
quality of a one-box player. generally, much better to buy a better
player than to use an outboard DAC for CD replay.

Judging by the prices that DACs are going for, I'm thinking that this would
be a good improvement over the existing setup for less than the cost of a
comparable player. My mate's £500 Arcam player has quickly established
itself as something of a benchmark - I'd like to approach, or improve on,
that sort of quality if feasible. My thinking is that, when my existing
player starts to bite the dust, I could look at getting a transport that can
take a timing signal from a DAC. Is it a standard signal for all (most?)
transports/DACs, or is it rather proprietary?


I'm sure an oscilloscope is a much cheaper approach... ;-)

Actually, he's being coy. 'Better kit' in this case most certainly
does *not* include DACs which can't suppress jitter in the datastream,
but they certainly cost a lot of money, and they do sound bad! :-)

Do you mean DACs that use a sync signal to control jitter, as opposed to
those which can take a raw datastream and make the best (or better) of it?
Would a DAC which has a sync output and a bunch of oversampling be the right
thing to go chasing after?


As noted, try Meridian DACs - they sound good and they do a good job
of suppressing jitter. I'm not sure that you'll notice much difference
between the original 203 and the later models, as they always had the
engineering pretty well spot on.

Duly noted.


--
Wally
www.art-gallery.myby.co.uk
Latest work: The Langlois Bridge (after Van Gogh)

Add a DAC to a cheap CD player?
 

Stewart Pinkerton wrote:

Not 'necessary', but it does help an outboard DAC to approach the
quality of a one-box player. generally, much better to buy a better
player than to use an outboard DAC for CD replay.

Judging by the prices that DACs are going for, I'm thinking that this would
be a good improvement over the existing setup for less than the cost of a
comparable player. My mate's £500 Arcam player has quickly established
itself as something of a benchmark - I'd like to approach, or improve on,
that sort of quality if feasible. My thinking is that, when my existing
player starts to bite the dust, I could look at getting a transport that can
take a timing signal from a DAC. Is it a standard signal for all (most?)
transports/DACs, or is it rather proprietary?


I'm sure an oscilloscope is a much cheaper approach... ;-)

Actually, he's being coy. 'Better kit' in this case most certainly
does *not* include DACs which can't suppress jitter in the datastream,
but they certainly cost a lot of money, and they do sound bad! :-)

Do you mean DACs that use a sync signal to control jitter, as opposed to
those which can take a raw datastream and make the best (or better) of it?
Would a DAC which has a sync output and a bunch of oversampling be the right
thing to go chasing after?


As noted, try Meridian DACs - they sound good and they do a good job
of suppressing jitter. I'm not sure that you'll notice much difference
between the original 203 and the later models, as they always had the
engineering pretty well spot on.

Duly noted.


--
Wally
www.art-gallery.myby.co.uk
Latest work: The Langlois Bridge (after Van Gogh)

Add a DAC to a cheap CD player?
 

"Wally" wrote in message
...
Jim Lesurf wrote:

Afraid I don't know anything about the DVD/CD player you have, so
can't really comment on it as such...

Silver-fronted jobbie. Asda were flogging them for £100 a few months ago.
Last seen at 70 quid before disappearing.


Wal-Mart sell Apex ones for 45 dollars or so, would be about 30 quid in the
UK.
and post Thanks-giving day sale they were $29.95 for a morning.
they have one playing movies on a TV and quite good pic quality.
silly prices now, don't know what the postage would be from the USA to the
UK,
and whether the customs would slap import duty on one.
regards malcolm

Add a DAC to a cheap CD player?
 

"Wally" wrote in message
...
Jim Lesurf wrote:

Afraid I don't know anything about the DVD/CD player you have, so
can't really comment on it as such...

Silver-fronted jobbie. Asda were flogging them for £100 a few months ago.
Last seen at 70 quid before disappearing.


Wal-Mart sell Apex ones for 45 dollars or so, would be about 30 quid in the
UK.
and post Thanks-giving day sale they were $29.95 for a morning.
they have one playing movies on a TV and quite good pic quality.
silly prices now, don't know what the postage would be from the USA to the
UK,
and whether the customs would slap import duty on one.
regards malcolm

Add a DAC to a cheap CD player?
 

On Tue, 09 Dec 2003 21:44:54 GMT
"Wally" wrote:


Do you mean DACs that use a sync signal to control jitter, as opposed
to those which can take a raw datastream and make the best (or better)
of it? Would a DAC which has a sync output and a bunch of oversampling
be the right thing to go chasing after?

No. the jitter on SPDIF will only minimally impact the output on a well
designed dac.

a 'reclocked' signal is almost garaunteed to be a worse output (not
necessarily distinguishable, mind) quality output.

With the 'async' SPDIF you will hear every bit correctly (and thats
still dependant on the conversion method). with a reclocked output,
given the clock will NEVER be a perfect match for the SPDIF clock
anyway, you are garaunteed to either drop or stretch a whole bit at some
point. ick.

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with
ketchup.

Add a DAC to a cheap CD player?
 

On Tue, 09 Dec 2003 21:44:54 GMT
"Wally" wrote:


Do you mean DACs that use a sync signal to control jitter, as opposed
to those which can take a raw datastream and make the best (or better)
of it? Would a DAC which has a sync output and a bunch of oversampling
be the right thing to go chasing after?

No. the jitter on SPDIF will only minimally impact the output on a well
designed dac.

a 'reclocked' signal is almost garaunteed to be a worse output (not
necessarily distinguishable, mind) quality output.

With the 'async' SPDIF you will hear every bit correctly (and thats
still dependant on the conversion method). with a reclocked output,
given the clock will NEVER be a perfect match for the SPDIF clock
anyway, you are garaunteed to either drop or stretch a whole bit at some
point. ick.

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with
ketchup.

Add a DAC to a cheap CD player?
 

On Wed, 10 Dec 2003 00:05:11 GMT, "malcolm"
wrote:

Wal-Mart sell Apex ones for 45 dollars or so, would be about 30 quid in the
UK.
and post Thanks-giving day sale they were $29.95 for a morning.
they have one playing movies on a TV and quite good pic quality.
silly prices now, don't know what the postage would be from the USA to the
UK,
and whether the customs would slap import duty on one.

To say nothing of the probable need for a step-down power transformer.

Kal

Add a DAC to a cheap CD player?
 

On Wed, 10 Dec 2003 00:05:11 GMT, "malcolm"
wrote:

Wal-Mart sell Apex ones for 45 dollars or so, would be about 30 quid in the
UK.
and post Thanks-giving day sale they were $29.95 for a morning.
they have one playing movies on a TV and quite good pic quality.
silly prices now, don't know what the postage would be from the USA to the
UK,
and whether the customs would slap import duty on one.

To say nothing of the probable need for a step-down power transformer.

Kal

Add a DAC to a cheap CD player?
 

On Tue, 09 Dec 2003 20:00:26 -0500
Kalman Rubinson wrote:

To say nothing of the probable need for a step-down power transformer.

Actually a LOT of modern equipment uses SMPSUs, which are (these days)
designed to run between 90 and 250V typically, and so will work fine
wherever...

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with
ketchup.

Add a DAC to a cheap CD player?
 

On Tue, 09 Dec 2003 20:00:26 -0500
Kalman Rubinson wrote:

To say nothing of the probable need for a step-down power transformer.

Actually a LOT of modern equipment uses SMPSUs, which are (these days)
designed to run between 90 and 250V typically, and so will work fine
wherever...

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with
ketchup.

Add a DAC to a cheap CD player?
 

malcolm wrote:

Silver-fronted jobbie. Asda were flogging them for £100 a few months
ago. Last seen at 70 quid before disappearing.

Wal-Mart sell Apex ones for 45 dollars or so, would be about 30 quid
in the UK.
and post Thanks-giving day sale they were $29.95 for a morning.
they have one playing movies on a TV and quite good pic quality.
silly prices now, don't know what the postage would be from the USA
to the UK,
and whether the customs would slap import duty on one.

I already have a player - I'm looking into improving it with a DAC.


--
Wally
www.art-gallery.myby.co.uk
Latest work: The Langlois Bridge (after Van Gogh)

Add a DAC to a cheap CD player?
 

malcolm wrote:

Silver-fronted jobbie. Asda were flogging them for £100 a few months
ago. Last seen at 70 quid before disappearing.

Wal-Mart sell Apex ones for 45 dollars or so, would be about 30 quid
in the UK.
and post Thanks-giving day sale they were $29.95 for a morning.
they have one playing movies on a TV and quite good pic quality.
silly prices now, don't know what the postage would be from the USA
to the UK,
and whether the customs would slap import duty on one.

I already have a player - I'm looking into improving it with a DAC.


--
Wally
www.art-gallery.myby.co.uk
Latest work: The Langlois Bridge (after Van Gogh)

Add a DAC to a cheap CD player?
 

Ian Molton wrote:

With the 'async' SPDIF you will hear every bit correctly (and thats
still dependant on the conversion method). with a reclocked output,
given the clock will NEVER be a perfect match for the SPDIF clock
anyway, you are garaunteed to either drop or stretch a whole bit at
some point. ick.

So, what's the difference between async and reclocked? If reclocking is
about feeding back time adjustment info from DAC to transport, does
asynchronus mean there's some sort of buffering in the DAC?


--
Wally
www.art-gallery.myby.co.uk
Latest work: The Langlois Bridge (after Van Gogh)

Add a DAC to a cheap CD player?
 

Ian Molton wrote:

With the 'async' SPDIF you will hear every bit correctly (and thats
still dependant on the conversion method). with a reclocked output,
given the clock will NEVER be a perfect match for the SPDIF clock
anyway, you are garaunteed to either drop or stretch a whole bit at
some point. ick.

So, what's the difference between async and reclocked? If reclocking is
about feeding back time adjustment info from DAC to transport, does
asynchronus mean there's some sort of buffering in the DAC?


--
Wally
www.art-gallery.myby.co.uk
Latest work: The Langlois Bridge (after Van Gogh)

Add a DAC to a cheap CD player?
 

On Wed, 10 Dec 2003 01:15:00 GMT
"Wally" wrote:


So, what's the difference between async and reclocked? If reclocking is
about feeding back time adjustment info from DAC to transport, does
asynchronus mean there's some sort of buffering in the DAC?

thats not reality, sorry.

the 'reclocked' signal is simply one that has been resynchronised to another clock, with bits added / discarded to suit the difference in clock speed between the spdif clock and the reference one.

neither this or what I called 'async' above has any feedback at all.

Given the choice, I'd go for the lesser of two evils - the raw, unadulterated signal.

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with ketchup.

Add a DAC to a cheap CD player?
 

On Wed, 10 Dec 2003 01:15:00 GMT
"Wally" wrote:


So, what's the difference between async and reclocked? If reclocking is
about feeding back time adjustment info from DAC to transport, does
asynchronus mean there's some sort of buffering in the DAC?

thats not reality, sorry.

the 'reclocked' signal is simply one that has been resynchronised to another clock, with bits added / discarded to suit the difference in clock speed between the spdif clock and the reference one.

neither this or what I called 'async' above has any feedback at all.

Given the choice, I'd go for the lesser of two evils - the raw, unadulterated signal.

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with ketchup.

Add a DAC to a cheap CD player?
 

On Wed, 10 Dec 2003 02:12:49 +0000, Ian Molton wrote:

On Wed, 10 Dec 2003 01:15:00 GMT
"Wally" wrote:


So, what's the difference between async and reclocked? If reclocking is
about feeding back time adjustment info from DAC to transport, does
asynchronus mean there's some sort of buffering in the DAC?

thats not reality, sorry.

the 'reclocked' signal is simply one that has been resynchronised to
another clock, with bits added / discarded to suit the difference in
clock speed between the spdif clock and the reference one.

I wonder - would the DAC ensure the discarded bits are the least
significent ones?
If so wouldn't the worst reclocking can do just lower the resolution from
16 to 15
bits for 1/44000 of a second?

To minimise this effect components should be placed side by side, not
stacked.
Most hi-end gear was not designed to handle the effects of relitivity.

--
Jim H jh
@333
.org

Add a DAC to a cheap CD player?
 

On Wed, 10 Dec 2003 02:12:49 +0000, Ian Molton wrote:

On Wed, 10 Dec 2003 01:15:00 GMT
"Wally" wrote:


So, what's the difference between async and reclocked? If reclocking is
about feeding back time adjustment info from DAC to transport, does
asynchronus mean there's some sort of buffering in the DAC?

thats not reality, sorry.

the 'reclocked' signal is simply one that has been resynchronised to
another clock, with bits added / discarded to suit the difference in
clock speed between the spdif clock and the reference one.

I wonder - would the DAC ensure the discarded bits are the least
significent ones?
If so wouldn't the worst reclocking can do just lower the resolution from
16 to 15
bits for 1/44000 of a second?

To minimise this effect components should be placed side by side, not
stacked.
Most hi-end gear was not designed to handle the effects of relitivity.

--
Jim H jh
@333
.org

Add a DAC to a cheap CD player?
 

"Wally" wrote in message
...
malcolm wrote:

Silver-fronted jobbie. Asda were flogging them for £100 a few months
ago. Last seen at 70 quid before disappearing.

Wal-Mart sell Apex ones for 45 dollars or so, would be about 30 quid
in the UK.
and post Thanks-giving day sale they were $29.95 for a morning.
they have one playing movies on a TV and quite good pic quality.
silly prices now, don't know what the postage would be from the USA
to the UK,
and whether the customs would slap import duty on one.

I already have a player - I'm looking into improving it with a DAC.


--
Wally
www.art-gallery.myby.co.uk
Latest work: The Langlois Bridge (after Van Gogh)




just comparing price differences etc

Add a DAC to a cheap CD player?
 

"Wally" wrote in message
...
malcolm wrote:

Silver-fronted jobbie. Asda were flogging them for £100 a few months
ago. Last seen at 70 quid before disappearing.

Wal-Mart sell Apex ones for 45 dollars or so, would be about 30 quid
in the UK.
and post Thanks-giving day sale they were $29.95 for a morning.
they have one playing movies on a TV and quite good pic quality.
silly prices now, don't know what the postage would be from the USA
to the UK,
and whether the customs would slap import duty on one.

I already have a player - I'm looking into improving it with a DAC.


--
Wally
www.art-gallery.myby.co.uk
Latest work: The Langlois Bridge (after Van Gogh)




just comparing price differences etc

Add a DAC to a cheap CD player?
 

On Wed, 10 Dec 2003 03:04:30 -0000
Jim H wrote:

I wonder - would the DAC ensure the discarded bits are the least
significent ones?
If so wouldn't the worst reclocking can do just lower the resolution from
16 to 15
bits for 1/44000 of a second?

You tell me. I dont know what the DACs are doing internally.

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with ketchup.

Add a DAC to a cheap CD player?
 

On Wed, 10 Dec 2003 03:04:30 -0000
Jim H wrote:

I wonder - would the DAC ensure the discarded bits are the least
significent ones?
If so wouldn't the worst reclocking can do just lower the resolution from
16 to 15
bits for 1/44000 of a second?

You tell me. I dont know what the DACs are doing internally.

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with ketchup.

Add a DAC to a cheap CD player?
 

On Tue, 09 Dec 2003 16:53:29 +0000 (GMT)
Jim Lesurf wrote:

For my taste the Meridian DACs seem excellent.

Do you know anything about the ARCAM Delta black box 3?

does it sound good?

does it have an optical input?

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with ketchup.

Add a DAC to a cheap CD player?
 

On Tue, 09 Dec 2003 16:53:29 +0000 (GMT)
Jim Lesurf wrote:

For my taste the Meridian DACs seem excellent.

Do you know anything about the ARCAM Delta black box 3?

does it sound good?

does it have an optical input?

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with ketchup.

Add a DAC to a cheap CD player?
 

In article , Ian Molton
wrote:
On Wed, 10 Dec 2003 01:15:00 GMT "Wally" wrote:


So, what's the difference between async and reclocked? If reclocking
is about feeding back time adjustment info from DAC to transport, does
asynchronus mean there's some sort of buffering in the DAC?

thats not reality, sorry.

the 'reclocked' signal is simply one that has been resynchronised to
another clock, with bits added / discarded to suit the difference in
clock speed between the spdif clock and the reference one.

neither this or what I called 'async' above has any feedback at all.

Alas, this is an area where most of the terms used have become ambiguous or
vague due to being used by marketing types to mean different things in
different cases. Hence terms like 'reclocked', 'upsampled', etc, should now
be treated with caution. :-/

The S/PDIF data stream contains its own 'clock info' mixed in with the
signal. A reciever (DAC) can if it wishes seek to 'recover' this clock
info, and then use it to control its own 'local clock'. Methods for doing
this vary, but the obvious one is a phase lock loop. It also tends to imply
some data buffering in the receiver to give the clocks some elbow room to
get out of timestep without data loss, and to give a longer running average
time for the local clock smoothing. However all these details will depend
entirely upon how a given receiver was designed/built.

In the absence of any attempts to 'fiddle with the clock', the most basic
approach would just read in each (serial) digital value (stereo pair), and
then when it arrived, shove it through the system and output a fresh
analogue level. However this would mean that any irregularities in timing
will modulate the output.

By having a subsystem that looks for the clock info in the input stream,
and use this to control a local clock, you can output data at a (nominally)
smoother rate. This can only deal with 'short term' variations, though, and
where the size of the jitter is reasonably small. Nor can it entirely
remove any effect, just reduce them to some extent.

DACs like the Meridian ones apply control loops to read in the data, and
then play them out under the control of a 'smoothed' local clock. This can
reduce the effects of jitter provided the input isn't too bad. Other DACs
may use various methods (or none at all) to try and deal with this. When I
first bought a Meridian DAC I assumed that all DACs did this, and used the
methods I'm familiar with from data comms. However I was surprised later on
to be told that they did not.

'Upsampling' and some other terms are really about addressing another area.

Whether jitter is a significant - i.e. audible - problem in most cases is
another matter. I like the Meridian DACs, but have no idea if 'jitter
reduction' has anything to do with that! :-)

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

Add a DAC to a cheap CD player?
 

In article , Ian Molton
wrote:
On Wed, 10 Dec 2003 01:15:00 GMT "Wally" wrote:


So, what's the difference between async and reclocked? If reclocking
is about feeding back time adjustment info from DAC to transport, does
asynchronus mean there's some sort of buffering in the DAC?

thats not reality, sorry.

the 'reclocked' signal is simply one that has been resynchronised to
another clock, with bits added / discarded to suit the difference in
clock speed between the spdif clock and the reference one.

neither this or what I called 'async' above has any feedback at all.

Alas, this is an area where most of the terms used have become ambiguous or
vague due to being used by marketing types to mean different things in
different cases. Hence terms like 'reclocked', 'upsampled', etc, should now
be treated with caution. :-/

The S/PDIF data stream contains its own 'clock info' mixed in with the
signal. A reciever (DAC) can if it wishes seek to 'recover' this clock
info, and then use it to control its own 'local clock'. Methods for doing
this vary, but the obvious one is a phase lock loop. It also tends to imply
some data buffering in the receiver to give the clocks some elbow room to
get out of timestep without data loss, and to give a longer running average
time for the local clock smoothing. However all these details will depend
entirely upon how a given receiver was designed/built.

In the absence of any attempts to 'fiddle with the clock', the most basic
approach would just read in each (serial) digital value (stereo pair), and
then when it arrived, shove it through the system and output a fresh
analogue level. However this would mean that any irregularities in timing
will modulate the output.

By having a subsystem that looks for the clock info in the input stream,
and use this to control a local clock, you can output data at a (nominally)
smoother rate. This can only deal with 'short term' variations, though, and
where the size of the jitter is reasonably small. Nor can it entirely
remove any effect, just reduce them to some extent.

DACs like the Meridian ones apply control loops to read in the data, and
then play them out under the control of a 'smoothed' local clock. This can
reduce the effects of jitter provided the input isn't too bad. Other DACs
may use various methods (or none at all) to try and deal with this. When I
first bought a Meridian DAC I assumed that all DACs did this, and used the
methods I'm familiar with from data comms. However I was surprised later on
to be told that they did not.

'Upsampling' and some other terms are really about addressing another area.

Whether jitter is a significant - i.e. audible - problem in most cases is
another matter. I like the Meridian DACs, but have no idea if 'jitter
reduction' has anything to do with that! :-)

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

Add a DAC to a cheap CD player?
 

In article , Jim H
wrote:
On Wed, 10 Dec 2003 02:12:49 +0000, Ian Molton wrote:

On Wed, 10 Dec 2003 01:15:00 GMT "Wally" wrote:


So, what's the difference between async and reclocked? If reclocking
is about feeding back time adjustment info from DAC to transport,
does asynchronus mean there's some sort of buffering in the DAC?

thats not reality, sorry.

the 'reclocked' signal is simply one that has been resynchronised to
another clock, with bits added / discarded to suit the difference in
clock speed between the spdif clock and the reference one.

I wonder - would the DAC ensure the discarded bits are the least
significent ones? If so wouldn't the worst reclocking can do just lower
the resolution from 16 to 15 bits for 1/44000 of a second?

Alas, the DAC has no real control over what bits might be lost due to
jitter, or noise. These problems are not under its control at source.

To minimise this effect components should be placed side by side, not
stacked. Most hi-end gear was not designed to handle the effects of
relitivity.

Eh?

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

Add a DAC to a cheap CD player?
 

In article , Jim H
wrote:
On Wed, 10 Dec 2003 02:12:49 +0000, Ian Molton wrote:

On Wed, 10 Dec 2003 01:15:00 GMT "Wally" wrote:


So, what's the difference between async and reclocked? If reclocking
is about feeding back time adjustment info from DAC to transport,
does asynchronus mean there's some sort of buffering in the DAC?

thats not reality, sorry.

the 'reclocked' signal is simply one that has been resynchronised to
another clock, with bits added / discarded to suit the difference in
clock speed between the spdif clock and the reference one.

I wonder - would the DAC ensure the discarded bits are the least
significent ones? If so wouldn't the worst reclocking can do just lower
the resolution from 16 to 15 bits for 1/44000 of a second?

Alas, the DAC has no real control over what bits might be lost due to
jitter, or noise. These problems are not under its control at source.

To minimise this effect components should be placed side by side, not
stacked. Most hi-end gear was not designed to handle the effects of
relitivity.

Eh?

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

Add a DAC to a cheap CD player?
 

Wally wrote:


Judging by the prices that DACs are going for, I'm thinking that this would
be a good improvement over the existing setup for less than the cost of a
comparable player. My mate's £500 Arcam player has quickly established
itself as something of a benchmark - I'd like to approach, or improve on,
that sort of quality if feasible. My thinking is that, when my existing
player starts to bite the dust, I could look at getting a transport that can
take a timing signal from a DAC. Is it a standard signal for all (most?)
transports/DACs, or is it rather proprietary?

I'm sure an oscilloscope is a much cheaper approach... ;-)

Actually, he's being coy. 'Better kit' in this case most certainly
does *not* include DACs which can't suppress jitter in the datastream,
but they certainly cost a lot of money, and they do sound bad! :-)

Do you mean DACs that use a sync signal to control jitter, as opposed to
those which can take a raw datastream and make the best (or better) of it?
Would a DAC which has a sync output and a bunch of oversampling be the right
thing to go chasing after?


The best value for money in jitter immune DAC's is reputed to be the
Benchmark DAC1 which uses a sample rate convertor in front of the DAC.
It is a little out of your price range at $850 (no UK distributor
either).

I'd forget about word clock outputs for your purpose - very few CD
players can actually use them.

Cheers.

James.