[RoninTO]

Hello Folks,
Can anyone recommend a really good sounding DAC at a reasonable
price. I know reasonable is relative in this industry and I have
spent when I thought it was important to but does one need to spend
thousands of dollars on a DAC or are there great performers at good
prices (under $500). Do you get what you pay for when buying a DAC.
I understand there are only a number of chipsets used by DACs and I
liken a DAC to a PC. I can build a PC cheaper from 3rd party
components that will out perform the big brand names. Wouldn't DACs
behave the same way...the more bits and over sampling the better?

Thank you in advance....

[Sonnova]

On Thu, 19 Feb 2009 20:14:26 -0800, RoninTO wrote
(in article ):

Hello Folks,
Can anyone recommend a really good sounding DAC at a reasonable
price. I know reasonable is relative in this industry and I have
spent when I thought it was important to but does one need to spend
thousands of dollars on a DAC or are there great performers at good
prices (under $500). Do you get what you pay for when buying a DAC.
I understand there are only a number of chipsets used by DACs and I
liken a DAC to a PC. I can build a PC cheaper from 3rd party
components that will out perform the big brand names. Wouldn't DACs
behave the same way...the more bits and over sampling the better?

Thank you in advance....

Cambridge DacMagic

http://www.head-case.org/forums/home...mbridge-audio-
dacmagic-400-balanced.html

[Dick Bowman]

On 20 Feb 2009 04:14:26 GMT, RoninTO wrote:

Hello Folks,
Can anyone recommend a really good sounding DAC at a reasonable
price. I know reasonable is relative in this industry and I have
spent when I thought it was important to but does one need to spend
thousands of dollars on a DAC or are there great performers at good
prices (under $500). Do you get what you pay for when buying a DAC.
I understand there are only a number of chipsets used by DACs and I
liken a DAC to a PC. I can build a PC cheaper from 3rd party
components that will out perform the big brand names. Wouldn't DACs
behave the same way...the more bits and over sampling the better?

Thank you in advance....

I'm not sure that the PC analogy holds (there are so many short cuts
available to the really big manufacturers).

But I sense that you are correct in thinking that the core DAC chipsets are
pretty much commodity items and that the supporting infrastructure ought to
be pretty much run-of-the-mill design. Also that a high proportion of the
cost of a commersial unit is in the casework/sockets/switches (let alone
how the price is carved up).

[Arny Krueger]

"RoninTO" wrote in message

Hello Folks,
Can anyone recommend a really good sounding DAC at a
reasonable price.

The one that is already in the piece of gear you were thinking about
attaching to the DAC. Can't beat the price and if it is reasonably new, its
probably better than any media you'll play through it.

[Sonnova]

On Fri, 20 Feb 2009 07:51:26 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

Hello Folks,
Can anyone recommend a really good sounding DAC at a
reasonable price.

The one that is already in the piece of gear you were thinking about
attaching to the DAC. Can't beat the price and if it is reasonably new, its
probably better than any media you'll play through it.


You're overlooking something. Their are some music server applications that
need a DAC and few CD players et al allow outside sources.

[Rob Tweed]

On 20 Feb 2009 04:14:26 GMT, RoninTO wrote:

Hello Folks,
Can anyone recommend a really good sounding DAC at a reasonable
price. I know reasonable is relative in this industry and I have
spent when I thought it was important to but does one need to spend
thousands of dollars on a DAC or are there great performers at good
prices (under $500). Do you get what you pay for when buying a DAC.
I understand there are only a number of chipsets used by DACs and I
liken a DAC to a PC. I can build a PC cheaper from 3rd party
components that will out perform the big brand names. Wouldn't DACs
behave the same way...the more bits and over sampling the better?

Thank you in advance....

My recommendation would be the EMU 0404USB
(http://www.emu.com/products/product.asp?product=15185)
which is a standalone USB-based box. Great sound at a bargain price.

.....and it's an ADC too, and a very good one at that.

---

Rob Tweed
Company: M/Gateway Developments Ltd
Registered in England: No 3220901
Registered Office: 58 Francis Road,Ashford, Kent TN23 7UR

Web-site: http://www.mgateway.com

[RoninTO]

On Feb 20, 12:41*pm, Sonnova wrote:
On Fri, 20 Feb 2009 07:51:26 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

Hello Folks,
Can anyone recommend a really good sounding DAC at a
reasonable price.

The one that is already in the piece of gear you were thinking about
attaching to the DAC. *Can't beat the price and if it is reasonably new, its
probably better than any media you'll play through it.

You're overlooking something. Their are some music server applications that
need a DAC and few CD players et al allow outside sources.

Yes...I am looking for an external DAC to work with my media player.
The Sonos product has a great interface for accessing music from my
network but the built in DAC is lacking in top end fidelity and sound
staging. I don't believe the Sonos product was ever intended for high
end audio. It is a great multi-room home audio solution.

[RoninTO]

On Feb 20, 10:50*am, Dick Bowman wrote:
On 20 Feb 2009 04:14:26 GMT, RoninTO wrote:

Hello Folks,
Can anyone recommend a really good sounding DAC at a reasonable
price. *I know reasonable is relative in this industry and I have
spent when I thought it was important to but does one need to spend
thousands of dollars on a DAC or are there great performers at good
prices (under $500). *Do you get what you pay for when buying a DAC.
I understand there are only a number of chipsets used by DACs and I
liken a DAC to a PC. *I can build a PC cheaper from 3rd party
components that will out perform the big brand names. *Wouldn't DACs
behave the same way...the more bits and over sampling the better?

Thank you in advance....

I'm not sure that the PC analogy holds (there are so many short cuts
available to the really big manufacturers).

But I sense that you are correct in thinking that the core DAC chipsets are
pretty much commodity items and that the supporting infrastructure ought to
be pretty much run-of-the-mill design. *Also that a high proportion of the
cost of a commersial unit is in the casework/sockets/switches (let alone
how the price is carved up).

I hate to say it but I believe the majority cost associated with the
production and commercialization of a high end DAC unit is marketing.
Preception is reality for those willing to pay, especially in high end
audio.

[Arny Krueger]

"RoninTO" wrote in message

On Feb 20, 12:41 pm, Sonnova
wrote:
On Fri, 20 Feb 2009 07:51:26 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

Hello Folks,
Can anyone recommend a really good sounding DAC at a
reasonable price.

The one that is already in the piece of gear you were
thinking about attaching to the DAC. Can't beat the
price and if it is reasonably new, its probably better
than any media you'll play through it.

You're overlooking something. Their are some music
server applications that need a DAC and few CD players
et al allow outside sources.

Don't they pretty universally have built- in DACs?

Yes...I am looking for an external DAC to work with my
media player. The Sonos product has a great interface for
accessing music from my network but the built in DAC is
lacking in top end fidelity and sound staging.

Says who?

I don't believe the Sonos product was ever intended for high end
audio. It is a great multi-room home audio solution.

These days even reasonbly cheap DAC chips are really pretty good.

The Sonos is not a particularly cheap device, I'd expect it to have a
built-in DAC that sounds and measures just fine.

[Sonnova]

On Sun, 22 Feb 2009 16:11:13 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

On Feb 20, 12:41 pm, Sonnova
wrote:
On Fri, 20 Feb 2009 07:51:26 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

Hello Folks,
Can anyone recommend a really good sounding DAC at a
reasonable price.

The one that is already in the piece of gear you were
thinking about attaching to the DAC. Can't beat the
price and if it is reasonably new, its probably better
than any media you'll play through it.

You're overlooking something. Their are some music
server applications that need a DAC and few CD players
et al allow outside sources.

Don't they pretty universally have built- in DACs?

Not very good ones. I.E. Most are 16-bit/44.1 KHz. Not much use if you are
serving 24-bit, 88, 96 or 192KHz audio.

[Arny Krueger]

"Sonnova" wrote in message

On Sun, 22 Feb 2009 16:11:13 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

On Feb 20, 12:41 pm, Sonnova
wrote:
On Fri, 20 Feb 2009 07:51:26 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

Hello Folks,
Can anyone recommend a really good sounding DAC at a
reasonable price.

The one that is already in the piece of gear you were
thinking about attaching to the DAC. Can't beat the
price and if it is reasonably new, its probably better
than any media you'll play through it.

You're overlooking something. Their are some music
server applications that need a DAC and few CD players
et al allow outside sources.

Don't they pretty universally have built- in DACs?

Not very good ones. I.E. Most are 16-bit/44.1 KHz. Not
much use if you are serving 24-bit, 88, 96 or 192KHz
audio.

Given that even $40 DVD players have DACs capable of 24/192, I find this
hard to believe.

[Sonnova]

On Mon, 23 Feb 2009 07:43:44 -0800, Arny Krueger wrote
(in article ):

"Sonnova" wrote in message

On Sun, 22 Feb 2009 16:11:13 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

On Feb 20, 12:41 pm, Sonnova
wrote:
On Fri, 20 Feb 2009 07:51:26 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

Hello Folks,
Can anyone recommend a really good sounding DAC at a
reasonable price.

The one that is already in the piece of gear you were
thinking about attaching to the DAC. Can't beat the
price and if it is reasonably new, its probably better
than any media you'll play through it.

You're overlooking something. Their are some music
server applications that need a DAC and few CD players
et al allow outside sources.

Don't they pretty universally have built- in DACs?

Not very good ones. I.E. Most are 16-bit/44.1 KHz. Not
much use if you are serving 24-bit, 88, 96 or 192KHz
audio.

Given that even $40 DVD players have DACs capable of 24/192, I find this
hard to believe.



How do you get a 24-bit 192KHz wave file THROUGH a DVD player? Very few (if
any) have auxiliary inputs that give one access to those DACs. You'd have to
burn a 24-bit, 192KHz DVD of every download to use the DACs in the average
DVD player. I was under the impression that the whole idea of high-res
downloads was to eliminate physical media.

[Arny Krueger]

"Sonnova" wrote in message

On Mon, 23 Feb 2009 07:43:44 -0800, Arny Krueger wrote
(in article ):

"Sonnova" wrote in message

On Sun, 22 Feb 2009 16:11:13 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

On Feb 20, 12:41 pm, Sonnova
wrote:
On Fri, 20 Feb 2009 07:51:26 -0800, Arny Krueger
wrote (in article ):

"RoninTO" wrote in message

Hello Folks,
Can anyone recommend a really good sounding DAC at
a reasonable price.

The one that is already in the piece of gear you
were thinking about attaching to the DAC. Can't
beat the price and if it is reasonably new, its
probably better than any media you'll play through
it.

You're overlooking something. Their are some music
server applications that need a DAC and few CD
players et al allow outside sources.

Don't they pretty universally have built- in DACs?

Not very good ones. I.E. Most are 16-bit/44.1 KHz. Not
much use if you are serving 24-bit, 88, 96 or 192KHz
audio.

Given that even $40 DVD players have DACs capable of
24/192, I find this hard to believe.

How do you get a 24-bit 192KHz wave file THROUGH a DVD
player?

DVD-A.

However this is not the point I was trying to make. My point is that even
very low cost DVD players can contain DAC chips that would be capable of
24/192 operation, regardless of whether or not the player would operate that
high. This fact contradicts the idea that cheap DVD players only have 16/44
DACs in them.

[Sonnova]

On Mon, 23 Feb 2009 14:08:30 -0800, Arny Krueger wrote
(in article ):

"Sonnova" wrote in message

On Mon, 23 Feb 2009 07:43:44 -0800, Arny Krueger wrote
(in article ):

"Sonnova" wrote in message

On Sun, 22 Feb 2009 16:11:13 -0800, Arny Krueger wrote
(in article ):

"RoninTO" wrote in message

On Feb 20, 12:41 pm, Sonnova
wrote:
On Fri, 20 Feb 2009 07:51:26 -0800, Arny Krueger
wrote (in article ):

"RoninTO" wrote in message

Hello Folks,
Can anyone recommend a really good sounding DAC at
a reasonable price.

The one that is already in the piece of gear you
were thinking about attaching to the DAC. Can't
beat the price and if it is reasonably new, its
probably better than any media you'll play through
it.

You're overlooking something. Their are some music
server applications that need a DAC and few CD
players et al allow outside sources.

Don't they pretty universally have built- in DACs?

Not very good ones. I.E. Most are 16-bit/44.1 KHz. Not
much use if you are serving 24-bit, 88, 96 or 192KHz
audio.

Given that even $40 DVD players have DACs capable of
24/192, I find this hard to believe.

How do you get a 24-bit 192KHz wave file THROUGH a DVD
player?

DVD-A.

However this is not the point I was trying to make. My point is that even
very low cost DVD players can contain DAC chips that would be capable of
24/192 operation, regardless of whether or not the player would operate that
high. This fact contradicts the idea that cheap DVD players only have 16/44
DACs in them.


I was referring to CD players and the DACs usually included in devices like
the Apple Airport Express or Logitech's Squeezebox. But, it doesn't really
matter. The fact remains that if someone wants to use/access their computer
music library (unless the computer is in the same room as their stereo
system) they are going to need an accessible DAC for anything other than MP3
and 16-bit, 44.1KHz sources. I'm also not convinced that all DACs sound alike
either.

[Arny Krueger]

"Sonnova" wrote in message


I was referring to CD players and the DACs usually
included in devices like the Apple Airport Express or
Logitech's Squeezebox.

In this day and age, I'd give the DAC the benefit of the doubt, and run some
tests on it with the Rightmark program.

People are actually doing this sort of thing for themselves on some of the
HTML audio forums I frequent. They are finding what insiders already know,
which is that even some of the cheapest DAC chips around are getting to be
pretty respectable.

For example, most portable digital players have converters with +/- 0.05 dB
frequency response and 90+ dB dynamic range.

For example, the motherboard-resident audio chips on PCs now routinely have
8 discrete analog output channels, +/-0.05 dB frequency response and 90+ dB
dynamic range. 10 years ago those numbers were +/- 6 dB or worse response
coupled with as little as 45 dB dynamic range.

The worst converters around are in CDROM drives. These converters are rarely
if ever used since the days of Win98, when windows started using a 100%
digital connection to play audio CDs.

Next up the food chain are the audio outputs of cheap portable CD players.
But the problem has not been the converters for a long time, the problem has
been the anti-shock buffers which used data compression.

The truth about modern converters is that their goodness is almost all in
their design. Once a good design has been committed to silicon, the
production costs are nearly nil - certainly under $1 in manufacturing
volumes. Between more efficient fabrication processes that put more gates on
the same amount of silicon, and the fact that silicon is being produced in
vast volumes, the need to cut back on complexity is reduced. More complexity
and speed - higher performance.

But, it doesn't really matter. The
fact remains that if someone wants to use/access their
computer music library (unless the computer is in the
same room as their stereo system) they are going to need
an accessible DAC for anything other than MP3 and 16-bit,
44.1KHz sources. I'm also not convinced that all DACs
sound alike either.

One of the more interesting web pages that sheds light on the issue of DAC
audibility has files that have been bounced through the converters on a $25
SoundBlaster card, up to 20 times.

Anybody can download one of the many PCABX comparators on the web and do
their own reliable, bias-controlled listening tests. I can definitely hear a
difference when the sound has been bounced many times, but I would not
characterize the flaws as being seriously objectionable.

After just a few bounces, nobody who does reliable tests has ever reported
hearing anything. Compare that grueling test to typical consumer use of
just the DAC half of the ADC/DAC pair that this test covers, and the fact
that we usually only listen to the first pass.

The presumption that a built-in DAC is causing a serious loss of sound
quality is no longer a good assumption.

[Sonnova]

On Tue, 24 Feb 2009 08:11:07 -0800, Arny Krueger wrote
(in article ):

"Sonnova" wrote in message


I was referring to CD players and the DACs usually
included in devices like the Apple Airport Express or
Logitech's Squeezebox.

In this day and age, I'd give the DAC the benefit of the doubt, and run some
tests on it with the Rightmark program.

People are actually doing this sort of thing for themselves on some of the
HTML audio forums I frequent. They are finding what insiders already know,
which is that even some of the cheapest DAC chips around are getting to be
pretty respectable.

I don't doubt it. The job of a DAC chip is pretty simple. The problems have
been that in the past, the linearity of the stair-steps varied greatly and
real linear DACs were a product of selection rather than process. IOW, the
most linear DACs were chosen from each wafer and priced at a premium while
the less accurate samples were priced lower. Today, the process is much more
tightly controllable, and while there might still be a spread between the
most linear DACs on a given wafer and the least linear, the yield of very
accurate DACs is much higher than it was a few years ago and the premium for
those very linear examples is much less. This means that manufacturers of
even fairly mundane equipment can afford to use DAC chips that, a few short
years ago, would have been found in only very high-end equipment. One still
finds great variance in such things as analog stages, anti-ailising filters,
power supplies and even the digital clock accuracy, etc.

For example, most portable digital players have converters with +/- 0.05 dB
frequency response and 90+ dB dynamic range.

For example, the motherboard-resident audio chips on PCs now routinely have
8 discrete analog output channels, +/-0.05 dB frequency response and 90+ dB
dynamic range. 10 years ago those numbers were +/- 6 dB or worse response
coupled with as little as 45 dB dynamic range.

The worst converters around are in CDROM drives. These converters are rarely
if ever used since the days of Win98, when windows started using a 100%
digital connection to play audio CDs.

Next up the food chain are the audio outputs of cheap portable CD players.
But the problem has not been the converters for a long time, the problem has
been the anti-shock buffers which used data compression.

Agreed.

The truth about modern converters is that their goodness is almost all in
their design. Once a good design has been committed to silicon, the
production costs are nearly nil - certainly under $1 in manufacturing
volumes. Between more efficient fabrication processes that put more gates on
the same amount of silicon, and the fact that silicon is being produced in
vast volumes, the need to cut back on complexity is reduced. More complexity
and speed - higher performance.

But, it doesn't really matter. The
fact remains that if someone wants to use/access their
computer music library (unless the computer is in the
same room as their stereo system) they are going to need
an accessible DAC for anything other than MP3 and 16-bit,
44.1KHz sources. I'm also not convinced that all DACs
sound alike either.

One of the more interesting web pages that sheds light on the issue of DAC
audibility has files that have been bounced through the converters on a $25
SoundBlaster card, up to 20 times.

When I say DAC, I'm not referring to the digital-to-analog converter chip,
I'm referring to the box that takes a digital signal from a coax, or an
optical connector and outputs a line-level audio signal.

Anybody can download one of the many PCABX comparators on the web and do
their own reliable, bias-controlled listening tests. I can definitely hear a
difference when the sound has been bounced many times, but I would not
characterize the flaws as being seriously objectionable.

After just a few bounces, nobody who does reliable tests has ever reported
hearing anything. Compare that grueling test to typical consumer use of
just the DAC half of the ADC/DAC pair that this test covers, and the fact
that we usually only listen to the first pass.

The presumption that a built-in DAC is causing a serious loss of sound
quality is no longer a good assumption.

While you are probably right, the quality of the DAC chips used in today's
players are pretty irrelevant when the listener wants to be able to stream
his "high-resolution" downloads from his computer to his stereo system. He's
going to have to buy a stand-alone DAC capable of the required 24-bit
resolution and the 192 KHz sampling rate (unless he's willing to have a
dedicated computer connected to his stereo system with a good sound card
on-board). These are not cheap and can easily cost more than a grand for
models like the excellent Benchmark DAC1. That's my only point here. I
mostly agree with the points you've made about the general quality of today's
DAC chips.

[[email protected]]

On Feb 24, 3:15*pm, Sonnova wrote:
The job of a DAC chip is pretty simple. The problems
have been that in the past, the linearity of the stair-
steps varied greatly and real linear DACs were a product
of selection rather than process.

That would be in the WAY WAY past, like more
than 25 years ago.

And the problem, when it existed, was solved not
through selection but through trimming.

IOW, the most linear DACs were chosen from
each wafer and priced at a premium while
the less accurate samples were priced lower.

You're talking the WAY ancient past, not much past the
very earliest CD players.

Today, the process is much more tightly controllable,

No, today a completely different architecture is used.
The VAST majority of audio DACs are based on
delta-sigma technology, where the step size is rendered
irrelevant altogether.

and while there might still be a spread between the
most linear DACs on a given wafer and the least
linear, the yield of very accurate DACs is much
higher than it was a few years ago and the premium for
those very linear examples is much less.

No, the yield is 100% for any of the ships that work.
Delta-sigma conversion makes this so.

One still finds great variance in such things as
analog stages, anti-ailising *filters,

There are no anti-aliasing filters in DACs, as they don't
alias. There ARE anti-imaging or reconstruction filters,
and, again, the architecture of DACs is something that
changed decades ago. Very few DACS have anti-imaging
filters physically separate from the actual converter:
it's not they they are physically associated: they work
together algorithmically in modern DACs.

power supplies and even the digital clock accuracy, etc.

All my assertion above are rendered moot by any
number of pathologically nutso high-end companies
that exhibit behaviors effectively indistinguishable
from grotesque technical incompetence that produce
products that, if they were presented in a company
with reasonable technical competence, would result
in the designer being summarily fired.

I'm speaking of "well regarded" and "respected"
(in the oxygen-deprived realm of high-end audio)
companies that make DACs with NO anti-imaging
filters, dreadful clock recovery designs, incompetent
mixed-signal design, and much, much more.

[Arny Krueger]

"Sonnova" wrote in message


I don't doubt it. The job of a DAC chip is pretty simple.
The problems have been that in the past, the linearity of
the stair-steps varied greatly and real linear DACs were
a product of selection rather than process. IOW, the most
linear DACs were chosen from each wafer and priced at a
premium while the less accurate samples were priced
lower. Today, the process is much more tightly
controllable, and while there might still be a spread
between the most linear DACs on a given wafer and the
least linear, the yield of very accurate DACs is much
higher than it was a few years ago and the premium for
those very linear examples is much less.

The big change happened about 18 years ago when they started making
delta-sigma converters. These chips are inherently linear and can't possibly
have missing codes in the middle of their range. It took a while to perfect
the technology. To some degree resolution can be traded off with speed, and
speed is something that modern chips have plenty of.

This means that
manufacturers of even fairly mundane equipment can afford
to use DAC chips that, a few short years ago, would have
been found in only very high-end equipment.

Exactly.

One still
finds great variance in such things as analog stages,
anti-aliasing filters,

DACs have no anti-aliasing filters, just low-pass reconstruction filters.
The other technological advance happened before delta-sigma, and that was
oversampling. The precison filters that are characteristic of excellent
converters were moved into the digital domain. Again, there's a
speed/performance tradeoff but again there is plenty of speed to trade off.
Not only are digital filters potentially far less expensive, but there is
considerably more latitude in the type of filter. So called Phase Linear
filters are now very, very common. They have essentially no phase
distortion, but instead act like a broadband delay line with fairly minimal
delay.

power supplies

Long a solved problem because of low-cost voltage regulator chips.

and even the digital clock accuracy, etc.

Digital clock accuracy and stability is another long-solved problem.


When I say DAC, I'm not referring to the
digital-to-analog converter chip, I'm referring to the
box that takes a digital signal from a coax, or an
optical connector and outputs a line-level audio signal.

The performance of that box is largely defined by the DAC chip. One of the
finest analog op amps for the past 3 decades has been the NE5534/32 which
again has become a very economical buy due to its maturity.

The presumption that a built-in DAC is causing a serious
loss of sound quality is no longer a good assumption.

While you are probably right, the quality of the DAC
chips used in today's players are pretty irrelevant when
the listener wants to be able to stream his
"high-resolution" downloads from his computer to his
stereo system.

The same chips that are used in digital music players are also used in
computers and computer interfaces.

He's going to have to buy a stand-alone
DAC capable of the required 24-bit resolution and the 192
KHz sampling rate (unless he's willing to have a
dedicated computer connected to his stereo system with a
good sound card on-board). These are not cheap and can
easily cost more than a grand for models like the
excellent Benchmark DAC1. That's my only point here. I
mostly agree with the points you've made about the
general quality of today's DAC chips.

The benchmark DAC-1 is vastly overpriced. You'll notice that there are no
reliable listening tests showing that it has a sonic advantage over far more
humble hardware, just anecdotes.

[Arny Krueger]

wrote in message


I'm speaking of "well regarded" and "respected"
(in the oxygen-deprived realm of high-end audio)
companies that make DACs with NO anti-imaging
filters, dreadful clock recovery designs, incompetent
mixed-signal design, and much, much more.

The really crazy part is the fact that many of these high attitude designers
actually brag about these deficiencies like they were features. And there's
apparently a market that actually gobbles it up.

[Sonnova]

On Tue, 24 Feb 2009 13:36:02 -0800, Arny Krueger wrote
(in article ):

"Sonnova" wrote in message


I don't doubt it. The job of a DAC chip is pretty simple.
The problems have been that in the past, the linearity of
the stair-steps varied greatly and real linear DACs were
a product of selection rather than process. IOW, the most
linear DACs were chosen from each wafer and priced at a
premium while the less accurate samples were priced
lower. Today, the process is much more tightly
controllable, and while there might still be a spread
between the most linear DACs on a given wafer and the
least linear, the yield of very accurate DACs is much
higher than it was a few years ago and the premium for
those very linear examples is much less.

The big change happened about 18 years ago when they started making
delta-sigma converters. These chips are inherently linear and can't possibly
have missing codes in the middle of their range. It took a while to perfect
the technology. To some degree resolution can be traded off with speed, and
speed is something that modern chips have plenty of.

This means that
manufacturers of even fairly mundane equipment can afford
to use DAC chips that, a few short years ago, would have
been found in only very high-end equipment.

Exactly.

One still
finds great variance in such things as analog stages,
anti-aliasing filters,

DACs have no anti-aliasing filters, just low-pass reconstruction filters.

I meant as part of the rest of the process, not the DAC chip itself. A
complete DAC processor has these things, not the DAC itself. Sorry for the
confusion.

The other technological advance happened before delta-sigma, and that was
oversampling. The precison filters that are characteristic of excellent
converters were moved into the digital domain. Again, there's a
speed/performance tradeoff but again there is plenty of speed to trade off.
Not only are digital filters potentially far less expensive, but there is
considerably more latitude in the type of filter. So called Phase Linear
filters are now very, very common. They have essentially no phase
distortion, but instead act like a broadband delay line with fairly minimal
delay.

power supplies

Long a solved problem because of low-cost voltage regulator chips.

and even the digital clock accuracy, etc.

Digital clock accuracy and stability is another long-solved problem.


When I say DAC, I'm not referring to the
digital-to-analog converter chip, I'm referring to the
box that takes a digital signal from a coax, or an
optical connector and outputs a line-level audio signal.

The performance of that box is largely defined by the DAC chip. One of the
finest analog op amps for the past 3 decades has been the NE5534/32 which
again has become a very economical buy due to its maturity.

The presumption that a built-in DAC is causing a serious
loss of sound quality is no longer a good assumption.

While you are probably right, the quality of the DAC
chips used in today's players are pretty irrelevant when
the listener wants to be able to stream his
"high-resolution" downloads from his computer to his
stereo system.

The same chips that are used in digital music players are also used in
computers and computer interfaces.

He's going to have to buy a stand-alone
DAC capable of the required 24-bit resolution and the 192
KHz sampling rate (unless he's willing to have a
dedicated computer connected to his stereo system with a
good sound card on-board). These are not cheap and can
easily cost more than a grand for models like the
excellent Benchmark DAC1. That's my only point here. I
mostly agree with the points you've made about the
general quality of today's DAC chips.

The benchmark DAC-1 is vastly overpriced. You'll notice that there are no
reliable listening tests showing that it has a sonic advantage over far more
humble hardware, just anecdotes.

Pretty moot point when the cheapest full-featured standalone DACs are about
$400 (the Cambridge DACMagic). They may well be overpriced, but if you want
one you have to pay their price. Even the Apogee Mini-DAC is around a grand.

[[email protected]]

On Feb 24, 6:19*pm, Sonnova wrote:
DACs have no anti-aliasing filters, just low-pass
reconstruction filters.

I meant as part of the rest of the process, not the
DAC chip itself. A complete DAC processor has
these things, not the DAC itself. Sorry for the
confusion.

No, they do not. DACs don't suffer from aliasing: that's
a sampling problem. No DAC, complete or otherwise,
an antialias filter. None. They have anti-imaging filters,
also known as reconstruction filters.

[Arny Krueger]

"Sonnova" wrote in message

On Tue, 24 Feb 2009 13:36:02 -0800, Arny Krueger wrote
(in article ):

"Sonnova" wrote in message


I don't doubt it. The job of a DAC chip is pretty
simple. The problems have been that in the past, the
linearity of the stair-steps varied greatly and real
linear DACs were a product of selection rather than
process. IOW, the most linear DACs were chosen from
each wafer and priced at a premium while the less
accurate samples were priced lower. Today, the process
is much more tightly controllable, and while there
might still be a spread between the most linear DACs on
a given wafer and the least linear, the yield of very
accurate DACs is much higher than it was a few years
ago and the premium for those very linear examples is
much less.

The big change happened about 18 years ago when they
started making delta-sigma converters. These chips are
inherently linear and can't possibly have missing codes
in the middle of their range. It took a while to perfect
the technology. To some degree resolution can be traded
off with speed, and speed is something that modern chips
have plenty of.

This means that
manufacturers of even fairly mundane equipment can
afford to use DAC chips that, a few short years ago,
would have been found in only very high-end equipment.

Exactly.

One still
finds great variance in such things as analog stages,
anti-aliasing filters,

DACs have no anti-aliasing filters, just low-pass
reconstruction filters.

I meant as part of the rest of the process, not the DAC
chip itself. A complete DAC processor has these things,
not the DAC itself. Sorry for the confusion.

DAC chips generally incorporate the filtering within themselves.


The benchmark DAC-1 is vastly overpriced. You'll notice
that there are no reliable listening tests showing that
it has a sonic advantage over far more humble hardware,
just anecdotes.

Pretty moot point when the cheapest full-featured
standalone DACs are about $400 (the Cambridge DACMagic).

Interesting. There are a number of full-featured standalone DACs being sold
on eBay by small, China-based manufacturers. There are extant technical
tests showing good performance.




They may well be overpriced, but if you want one you have
to pay their price. Even the Apogee Mini-DAC is around a
grand.

[Steve[_15_]]

I have a Squeezebox and believe it has a burr brown PCM1748. Are
Dpierce and Arny telling me that I am wasting my time if I try and
improve its sound via an external DAC?

Does this apply to head phone amps as well?

Also Arny said that benchmark DAC is overpriced and there are many
cheaper equivalents. Maybe you can list a few.

Steve

[Arny Krueger]

"Steve" wrote in message


I have a Squeezebox and believe it has a burr brown
PCM1748.

http://focus.ti.com/lit/ds/symlink/pcm1748.pdf

Seems like it has CD quality dynamic range, and bandwidth figuratively
coming out of its ears. Why would anyone want more?

Are Dpierce and Arny telling me that I am
wasting my time if I try and improve its sound via an
external DAC?

Yes.

Does this apply to head phone amps as well?

Well most line level outputs are not so good for driving low impedance
headphones. People tell me that these are good:

http://www.bhphotovideo.com/c/produc...Amplifier.html

or:

http://www.amazon.com/Behringer-Ultr.../dp/B000KU87SM

Also Arny said that benchmark DAC is overpriced and there
are many cheaper equivalents. Maybe you can list a few.

What you already got!

[[email protected]]

On Feb 25, 11:09*am, Steve wrote:
I have a Squeezebox and believe it has a burr brown PCM1748. Are
Dpierce and Arny telling me that I am wasting my time if I try and
improve its sound via an external DAC?

Possibly. Here are the Stereophile measurements of the Squeezebox:

http://www.stereophile.com/budgetcom...im/index3.html

Just what is it you think you'll be improving? Noise floor, maybe, but
unless you listen at screamingly loud volumes, I'm not sure you'll
notice.

Does this apply to head phone amps as well?

Not necessarily. Why should it? Amps and DACs are not the same thing.

Also Arny said that benchmark DAC is overpriced and there are many
cheaper equivalents. Maybe you can list a few.

Here's a DBT comparing the Benchmark to a Behringer unit.:

http://snipurl.com/cmp4v

The babelfish translation is a tough slog, but the bottom line is that
nobody could tell the difference.

bob

[[email protected]]

On Feb 25, 11:09 am, Steve wrote:
I have a Squeezebox and believe it has a burr brown PCM1748. Are
Dpierce and Arny telling me that I am wasting my time if I try and
improve its sound via an external DAC?

Care to show me where I made any such statement?

[Andrew Barss]

Arny Krueger wrote:
: "Steve" wrote in message
:

: I have a Squeezebox and believe it has a burr brown
: PCM1748.

: http://focus.ti.com/lit/ds/symlink/pcm1748.pdf

: Seems like it has CD quality dynamic range, and bandwidth figuratively
: coming out of its ears. Why would anyone want more?

A related question. I have a squeezebox, and just updated my receiver
to an Onkyo TX-SR706. I believe the Onkyo has a Cirrus Logic DAC. I'm assuming
there's no real difference between using the DAC in the Squeezebox,
and feeding the signal to the receiver's amp with analog cables, vs.
sending the feed out from the SB to the receiver over a digital optical cable
and using the receiver's DAC.

Am I corect in making this assumption?

-- Andy Barss

[dave a]

Arny Krueger wrote:
"Steve" wrote in message


I have a Squeezebox and believe it has a burr brown
PCM1748.

http://focus.ti.com/lit/ds/symlink/pcm1748.pdf

Seems like it has CD quality dynamic range, and bandwidth figuratively
coming out of its ears. Why would anyone want more?


Well, I would say the SNR is nothing to brag about. My 20 yr old Sony
X779ES with Sony DACs offers 119dB SNR vs the 106bD of the 1748.

Clearly, not all DACs are created equal, but their overall contribution
to the sound quality may be less than other parts of the system. In
other words, there are probably better ways to spend your money to
improve the sound.

[[email protected]]

On Feb 25, 7:53*pm, dave a wrote:

snip

Well, I would say the SNR is nothing to brag about. *My 20 yr old Sony
X779ES with Sony DACs offers 119dB SNR vs the 106bD of the 1748.

The SNR difference here is really unimportant. Recorded music rarely
has a dynamic range that exceeds 70 dB. Even with the "low" SNR of 106
dB, the noise in the recording is nearly 4 orders of magnitude
greater. CDs "only" have a dynamic range of 96 dB which again is
significantly lower than the noise floor in a recording.

Clearly, not all DACs are created equal, but their overall contribution
to the sound quality may be less than other parts of the system. *In
other words, there are probably better ways to spend your money to
improve the sound.

With modern chips, that is very true.

[David E. Bath]

In article ,
Andrew Barss writes:
Arny Krueger wrote:
: "Steve" wrote in message
:

: I have a Squeezebox and believe it has a burr brown
: PCM1748.

: http://focus.ti.com/lit/ds/symlink/pcm1748.pdf

: Seems like it has CD quality dynamic range, and bandwidth figuratively
: coming out of its ears. Why would anyone want more?

A related question. I have a squeezebox, and just updated my receiver
to an Onkyo TX-SR706. I believe the Onkyo has a Cirrus Logic DAC. I'm assuming
there's no real difference between using the DAC in the Squeezebox,
and feeding the signal to the receiver's amp with analog cables, vs.
sending the feed out from the SB to the receiver over a digital optical cable
and using the receiver's DAC.

Am I corect in making this assumption?

I found that I preferred connecting my CD player digitally to my
Yamaha receiver rather than analog. But the Yamaha has 24bit/96KHz
DACs while my CD player does not, so that could be why. Also, I'm
pretty sure the Yamaha digitizes the analog inputs so I am skipping a
DAC/ADC step by using the digital connection if true.

--
David Bath - RAHE Co-moderator

[Steve[_15_]]

On Feb 25, 7:49*pm, wrote:
On Feb 25, 11:09 am, Steve wrote:

I have a Squeezebox and believe it has a burr brown PCM1748. Are
Dpierce and Arny telling me that I am wasting my time if I try and
improve its sound via an external DAC?

Care to show me where I made any such statement?

My apologies if I misrepresented you.