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Anyone here know about CD test tone discs?

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January 11, 2005 12:00:55 AM

Archived from groups: rec.audio.pro (More info?)

I made a test CD using computer software (CEP) to generate sine waveforms to
test a home audio system... (the equipment you guys record for! ) BUT it sounded
very harsh... so I changed the levels down to -3db, and then to -6db, and now it
sounds better...

Isn't that weird?

What levels should I expect HI-FI gear to work at? It seems a waste to
not use the full spectrum, but I do see music CDs that seem to go up to
clipping and still sound OK... normally this system sounds very good with CDs.

Anyway - is there some trick to making a test CD in regards to levels?

Does CEP create bad waves?

thanks

More about : test tone discs

Anonymous
January 11, 2005 1:16:09 AM

Archived from groups: rec.audio.pro (More info?)

Bob <FlintsTone@Valve.Amps> wrote:
>
> I made a test CD using computer software (CEP) to generate sine waveforms to
>test a home audio system... (the equipment you guys record for! ) BUT it sounded
>very harsh... so I changed the levels down to -3db, and then to -6db, and now it
>sounds better...
>
> Isn't that weird?

I bet a nickel that if you look at the output with a scope, you will find
that your CD player has a linearity problem slightly below 0dBFS. This is
sadly very common with consumer players.

> What levels should I expect HI-FI gear to work at? It seems a waste to
> not use the full spectrum, but I do see music CDs that seem to go up to
>clipping and still sound OK... normally this system sounds very good with CDs.

I bet it would sound better with a good DAC... even a used DAC In the Box
maybe.

> Anyway - is there some trick to making a test CD in regards to levels?

No, I think you have a player problem. At least you aren't anywhere near
the first one.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
January 11, 2005 2:09:04 AM

Archived from groups: rec.audio.pro (More info?)

digital can never be perfect, long live the acetate ripping needle!!!!!
Related resources
Anonymous
January 11, 2005 9:01:14 AM

Archived from groups: rec.audio.pro (More info?)

"Scott Dorsey" <kludge@panix.com> wrote in message
news:crvgdp$8el$1@panix2.panix.com...
> Bob <FlintsTone@Valve.Amps> wrote:
> >
> > I made a test CD using computer software (CEP) to generate sine
waveforms to
> >test a home audio system... (the equipment you guys record for! ) BUT it
sounded
> >very harsh... so I changed the levels down to -3db, and then to -6db, and
now it
> >sounds better...
> >
> > Isn't that weird?
>
> I bet a nickel that if you look at the output with a scope, you will find
> that your CD player has a linearity problem slightly below 0dBFS. This is
> sadly very common with consumer players.

You want to really find nonlinearity problems in DACs...generate three tones
in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say) -1dBFS, then mix them
down at equal levels so the composite wave totals -0.1dBFS. Play that back
through your DAC, attenuate a few dB, and record the attenuated result into
a pro-quality sound card. You'll be surprised how much gunk a lot of DACs
put out.

For DACs, this seems to be a real torture test. Oh, it's a torture test for
tweeters too, so *don't* play it back through your speakers!

Peace,
Paul
Anonymous
January 11, 2005 9:19:56 AM

Archived from groups: rec.audio.pro (More info?)

On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler"
<pstamlerhell@pobox.com> wrote:

>You want to really find nonlinearity problems in DACs...generate three tones
>in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say) -1dBFS, then mix them
>down at equal levels so the composite wave totals -0.1dBFS. Play that back
>through your DAC, attenuate a few dB, and record the attenuated result into
>a pro-quality sound card. You'll be surprised how much gunk a lot of DACs
>put out.

But everybody knows that digital is (by definition) perfect. It's
been proven repeatedly and endlessly in ABCDE testing. Because
"Truth is stranger than fact."

Chris Hornbeck
"Conscious that we must have sprung from somewhere, we are
lured to the riddle of our origins." -Malcolm W. Browne
Anonymous
January 11, 2005 10:13:59 AM

Archived from groups: rec.audio.pro (More info?)

"Paul Stamler" <pstamlerhell@pobox.com> wrote in message
news:KYJEd.15362$c13.14073@bgtnsc04-news.ops.worldnet.att.net

> You want to really find nonlinearity problems in DACs...generate
> three tones in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say)
> -1dBFS, then mix them down at equal levels so the composite wave
> totals -0.1dBFS. Play that back through your DAC, attenuate a few dB,
> and record the attenuated result into a pro-quality sound card.
> You'll be surprised how much gunk a lot of DACs put out.

Agreed.

Been there, done that.

That's one reason why I've been telling people around here to set peak
levels at -1 dB for years.

It's also the reason why I've been telling people to do their Rightmark
tests with 18 & 20 KHz or 19 & 20 KHz CCIR-like IM test tones, not the
SMPTE-like easy stuff that it uses by default.

It can find a lot of converters with their hands in the cookie jar, too.
Anonymous
January 11, 2005 10:16:09 AM

Archived from groups: rec.audio.pro (More info?)

"siguy" <sjwatt@gmail.com> wrote in message
news:1105427344.401843.137590@f14g2000cwb.googlegroups.com

> digital can never be perfect, long live the acetate ripping
> needle!!!!!

Yes, I regret to admit that I just spent a lot of my winter vacation camping
in the Anza-Barrago (California) and Baja Mexico (Erindera) deserts and
failed to bring back any cactus needles.
January 11, 2005 12:33:09 PM

Archived from groups: rec.audio.pro (More info?)

Chris Hornbeck wrote:
> On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler"
> <pstamlerhell@pobox.com> wrote:
>
> >You want to really find nonlinearity problems in DACs...generate
three tones
> >in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say) -1dBFS, then mix
them
> >down at equal levels so the composite wave totals -0.1dBFS. Play
that back
> >through your DAC, attenuate a few dB, and record the attenuated
result into
> >a pro-quality sound card. You'll be surprised how much gunk a lot of
DACs
> >put out.
>
> But everybody knows that digital is (by definition) perfect. It's
> been proven repeatedly and endlessly in ABCDE testing. Because
> "Truth is stranger than fact."

Yes, that's a good test, but before you go blame digital for everything
bad,
try the same test with analog tape or vinal. Ha.

Mark
Anonymous
January 11, 2005 12:41:07 PM

Archived from groups: rec.audio.pro (More info?)

Paul Stamler <pstamlerhell@pobox.com> wrote:
Scott Dorsey writes:
>>
>> I bet a nickel that if you look at the output with a scope, you will find
>> that your CD player has a linearity problem slightly below 0dBFS. This is
>> sadly very common with consumer players.
>
>You want to really find nonlinearity problems in DACs...generate three tones
>in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say) -1dBFS, then mix them
>down at equal levels so the composite wave totals -0.1dBFS. Play that back
>through your DAC, attenuate a few dB, and record the attenuated result into
>a pro-quality sound card. You'll be surprised how much gunk a lot of DACs
>put out.

I can believe it. I'm not eve going that far, though, I am just talking
about analogue electronics after the converters that go into clipping before
the converter does.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
January 11, 2005 2:41:51 PM

Archived from groups: rec.audio.pro (More info?)

In article <2fc6u0lj5lgru9o4nch9dmnsnq5mlc5dr3@4ax.com> FlintsTone@Valve.Amps writes:

> I made a test CD using computer software (CEP) to generate sine waveforms to
> test a home audio system... (the equipment you guys record for! ) BUT it
> sounded
> very harsh... so I changed the levels down to -3db, and then to -6db, and now
> it
> sounds better...

If you made the disk at full scale, that may have indeed put too hot a
signal into your system from the CD player. In fact, a lot of CD
players themselves can't even handle a full scale signal without some
distortion.

> Anyway - is there some trick to making a test CD in regards to levels?

Make it at -10 dBFS or lower, maybe -20.


--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo
Anonymous
January 11, 2005 4:23:38 PM

Archived from groups: rec.audio.pro (More info?)

> But everybody knows that digital is (by definition) perfect.

Huh ???

May I please see that definition....
Anonymous
January 11, 2005 4:35:53 PM

Archived from groups: rec.audio.pro (More info?)

"siguy" <sjwatt@gmail.com> wrote in message
news:1105427344.401843.137590@f14g2000cwb.googlegroups.com

> digital can never be perfect, long live the acetate ripping
> needle!!!!!

Actually, the fault being described is probably on the analog side of the
converters.
Anonymous
January 11, 2005 6:39:48 PM

Archived from groups: rec.audio.pro (More info?)

Paul, I'm not sure of anything either (not having the player or the
waveform here in front of me) but I certainly have had similar
experiences. There used to be a highly-regarded brand of outboard DAC
called "Audio Alchemy" that was effusively recommended by Stereophile
and all the other magazines; after all, every audiophile knows that
separates always sound better than combined components, right?

Well, a few years ago I took one of those DACs and fed it a simple
midrange sine wave at about 1 dB below full scale (via its S-P/DIF
input), and the clipping was easily audible. If I recall correctly,
the audible distortion on sine waves began 1 - 2 dB lower than that.

You're certainly right that there can be clipping (sometimes quite
severe) in digital filters--but with such a simple waveform, I'd
consider the problem somewhat more likely to be on the analog side.
Anyway, most of this "free diagnosis over the Web" stuff is worth about
what you pay for it ...

--best regards
Anonymous
January 11, 2005 6:53:56 PM

Archived from groups: rec.audio.pro (More info?)

"Scott Dorsey"
> Bob
>>
>> I made a test CD using computer software (CEP) to generate sine waveforms
>> to
>>test a home audio system... (the equipment you guys record for! ) BUT it
>>sounded
>>very harsh... so I changed the levels down to -3db, and then to -6db, and
>>now it
>>sounds better...
>>
>> Isn't that weird?
>
> I bet a nickel that if you look at the output with a scope, you will find
> that your CD player has a linearity problem slightly below 0dBFS. This is
> sadly very common with consumer players.
>

** More utter bullshit from Dorsey to whom all facts are optional.


>> What levels should I expect HI-FI gear to work at? It seems a waste to
>> not use the full spectrum, but I do see music CDs that seem to go up to
>>clipping and still sound OK... normally this system sounds very good with
>>CDs.
>
> I bet it would sound better with a good DAC... even a used DAC In the Box
> maybe.


** Pig ignorant audiophool garbage.


>> Anyway - is there some trick to making a test CD in regards to levels?
>
> No, I think you have a player problem.


** Practically zero chance that is the case.



.......... Phil
Anonymous
January 11, 2005 6:53:57 PM

Archived from groups: rec.audio.pro (More info?)

>> No, I think you have a player problem.
>
>
>** Practically zero chance that is the case.


So what is the problem?

CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm
"Possibly the world's least impressive web site": George Perfect
Anonymous
January 11, 2005 6:53:58 PM

Archived from groups: rec.audio.pro (More info?)

"Laurence Payne" <l@laurenceDELETEpayne.freeserve.co.uk> wrote in
message news:2pk7u0htci5fakbt5sktk6hph1p3vnnuf8@4ax.com
>>> No, I think you have a player problem.
>>
>>
>> ** Practically zero chance that is the case.
>
>
> So what is the problem?

Probably a player problem.

I say this because its hard to generate a clipped waveform in Audition/CE
without going out of your way.

But, the initial defaults are to make a wave that peaks at 0 dB.
Anonymous
January 11, 2005 7:18:30 PM

Archived from groups: rec.audio.pro (More info?)

On Tue, 11 Jan 2005 10:42:15 -0500, "Arny Krueger" <arnyk@hotpop.com>
wrote:

>>>> No, I think you have a player problem.
>>>
>>>
>>> ** Practically zero chance that is the case.
>>
>>
>> So what is the problem?
>
>Probably a player problem.

So it's what Scott said? :-)

CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm
"Possibly the world's least impressive web site": George Perfect
Anonymous
January 11, 2005 7:18:31 PM

Archived from groups: rec.audio.pro (More info?)

"Laurence Payne" <l@laurenceDELETEpayne.freeserve.co.uk> wrote in
message news:82v7u0loi3pf2g3polv1giam3ai0fbrrds@4ax.com
> On Tue, 11 Jan 2005 10:42:15 -0500, "Arny Krueger" <arnyk@hotpop.com>
> wrote:
>
>>>>> No, I think you have a player problem.
>>>>
>>>>
>>>> ** Practically zero chance that is the case.
>>>
>>>
>>> So what is the problem?
>>
>> Probably a player problem.
>
> So it's what Scott said? :-)

(Putting fireproof suit on)

Yup!

;-)
Anonymous
January 11, 2005 7:57:43 PM

Archived from groups: rec.audio.pro (More info?)

>> Anyway - is there some trick to making a test CD in regards to levels?
>
>Make it at -10 dBFS or lower, maybe -20.

Make SOME tracks at that level, others at full-scale.
Looks like your playback setup fails the 0dB test. Isn't that what
tests are for?

CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm
"Possibly the world's least impressive web site": George Perfect
Anonymous
January 11, 2005 8:34:10 PM

Archived from groups: rec.audio.pro (More info?)

"Greg Taylor" <gtaylor@umd.umich.edu> wrote in message
news:a9UEd.123$UN1.95@news.itd.umich.edu

> ...which is surprising, given how hot current popular music cd's are
> mastered and replicated. One would think the better consumer players
> manufactured now would handle the max levels possible.

They do. Even some of the better $40 DVD players do FS sine waves at all
frequencies well. This problem was more common about 5 years ago.
Anonymous
January 11, 2005 9:04:34 PM

Archived from groups: rec.audio.pro (More info?)

On 11 Jan 2005 12:41:08 -0500, kludge@panix.com (Scott Dorsey) wrote:

> As I said, this is sadly very common. The analogue section clips
>or it least gets very ugly at a lower level than the converter itself.
>
>Personally I believe there is no excuse for that sort of thing.

Maybe they should be using LM301's in the I/V convertor. I
hear they're just about perfect.

Chris Hornbeck
"Conscious that we must have sprung from somewhere, we are
lured to the riddle of our origins." -Malcolm W. Browne
Anonymous
January 11, 2005 9:04:35 PM

Archived from groups: rec.audio.pro (More info?)

"Chris Hornbeck" <chrishornbeckremovethis@att.net> wrote in message
news:7558u0hvdudc435jdvmdc09njnps0ifb25@4ax.com
> On 11 Jan 2005 12:41:08 -0500, kludge@panix.com (Scott Dorsey) wrote:
>
>> As I said, this is sadly very common. The analogue section clips
>> or it least gets very ugly at a lower level than the converter
>> itself.

Or, there is clipping in the digital filter becuase its possible for signal
values to go above FS among intermediate values in a digital filter.

>> Personally I believe there is no excuse for that sort of thing.

Agreed, and it seems to be a lot less common. One thing that seems to have
happened is that a lot of very cheap suppliers have been blown off the
market by good suppliers like AKM and Crystal.

> Maybe they should be using LM301's in the I/V convertor. I
> hear they're just about perfect.

In fact they are usually using 5558s, which are something like a
dual-section, fixed-compensated LM301.
Anonymous
January 11, 2005 9:46:48 PM

Archived from groups: rec.audio.pro (More info?)

"siguy" <sjwatt@gmail.com> wrote in message
news:1105427344.401843.137590@f14g2000cwb.googlegroups.com...
> digital can never be perfect, long live the acetate ripping needle!!!!!

Exactly. If you're not going to get perfect, you may as well get as far away
from it as you can eh? :-)

MrT.
Anonymous
January 11, 2005 9:48:55 PM

Archived from groups: rec.audio.pro (More info?)

"Chris Hornbeck" <chrishornbeckremovethis@att.net> wrote in message
news:8dr6u01p59ajtg991qgrrf9c3e5hrh71dr@4ax.com...

> But everybody knows that digital is (by definition) perfect.

Exactly "by definition" only.

In the real world we even come a hell of a lot closer than anyone would have
expected 30 years ago!

MrT.
Anonymous
January 11, 2005 9:54:05 PM

Archived from groups: rec.audio.pro (More info?)

David Satz <DSatz@msn.com> wrote:
>Paul, I'm not sure of anything either (not having the player or the
>waveform here in front of me) but I certainly have had similar
>experiences. There used to be a highly-regarded brand of outboard DAC
>called "Audio Alchemy" that was effusively recommended by Stereophile
>and all the other magazines; after all, every audiophile knows that
>separates always sound better than combined components, right?
>
>Well, a few years ago I took one of those DACs and fed it a simple
>midrange sine wave at about 1 dB below full scale (via its S-P/DIF
>input), and the clipping was easily audible. If I recall correctly,
>the audible distortion on sine waves began 1 - 2 dB lower than that.

Was this the DAC-In-The-Box or one of the more expensive models?
As I recall, those had a generic Crystal sigma-delta chip inside.
I thought they sounded decent, though.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
January 11, 2005 10:17:07 PM

Archived from groups: rec.audio.pro (More info?)

Mark <makolber@yahoo.com> wrote:
>
>If you start with a (say) 5vp-p square wave and then filter it to
>REMOVE the harmonics, the resulting sine wave will be GREATER than 5
>Vp-p.
>
>This is true for analog as well as digital filters that someone
>mentioed previously.

This is correct, but I'm not sure it's relevant. Yes, overshoot will
result in values that exceed the nominal 0 dBFS value. But that's just
something the converter designer should design around.

>In a CD player, if the DAC can output 5vp-p, the reconstruction filter
>removes harmoincs and the resulting sine wave applied ot the anlog
>section can exceed 5vp-p. Some designers may not be aware of this and
>design the analog section for 5vp-p.

It might also happen in a sigma-delta system if the digital filter
used in the oversampling process overflows.

Either way the result is the same, and the result is unacceptable.
I don't think it matters WHY this happens so much as THAT it happens
and that we, as users, shouldn't put up with it.

>The same problem occurs in radio modulation limiters. If you set a
>hard limit to prevent overmodulation, and then filter to remove the
>resulting harmonics (which you must do) the filtered signal can exceed
>the original limited output and you can overmodulate.

Yup. Or even limiting before the NAB emphasis filter for FM can cause this.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
January 11, 2005 11:17:21 PM

Archived from groups: rec.audio.pro (More info?)

On Tue, 11 Jan 2005 12:37:10 -0500, Greg Taylor
<gtaylor@umd.umich.edu> wrote:

>...which is surprising, given how hot current popular music cd's are
>mastered and replicated. One would think the better consumer players
>manufactured now would handle the max levels possible.

Today's commercial recordings aren't QUITE sustained sine tones at
100% level :-)

CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm
"Possibly the world's least impressive web site": George Perfect
Anonymous
January 11, 2005 11:19:56 PM

Archived from groups: rec.audio.pro (More info?)

On 11 Jan 2005 12:41:08 -0500, kludge@panix.com (Scott Dorsey) wrote:

>Yes. As I said, this is sadly very common. The analogue section clips
>or it least gets very ugly at a lower level than the converter itself.
>
>Personally I believe there is no excuse for that sort of thing.

I wonder if there's any adjustment possible. This particular DC
player has always sounded "louder" than the original material.
Almost as if Sony thought it would sound more impressive if the signal
ran into a bit of limiting.

CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm
"Possibly the world's least impressive web site": George Perfect
Anonymous
January 11, 2005 11:43:03 PM

Archived from groups: rec.audio.pro (More info?)

In article <b3d8u01d5gb51ftrv338ltlpcv40fcjsah@4ax.com> l@laurenceDELETEpayne.freeserve.co.uk writes:

> I wonder if there's any adjustment possible. This particular DC
> player has always sounded "louder" than the original material.
> Almost as if Sony thought it would sound more impressive if the signal
> ran into a bit of limiting.

If that's the case, I wonder if it simply has a higher output for a
given digital level. When you play your full scale test CD through it,
even if it doesn't clip at its output (and it might, a little), it
might be putting out a hot enough signal so that it's clipping the
next thing in the chain.

Got an oscilloscope? There are a couple of freeware programs that will
make your computer with sound card work enough like one so that you
can look at clipping - as long as the level coming out of the CD
player doesn't clip the input of your sound card.

Sometimes you just need test equipment that's better than what you're
trying to test.

--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo
January 11, 2005 11:50:10 PM

Archived from groups: rec.audio.pro (More info?)

On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler" <pstamlerhell@pobox.com> wrote:

>"Scott Dorsey" <kludge@panix.com> wrote in message
>news:crvgdp$8el$1@panix2.panix.com...
>> Bob <FlintsTone@Valve.Amps> wrote:
>> >
>> > I made a test CD using computer software (CEP) to generate sine
>waveforms to
>> >test a home audio system... (the equipment you guys record for! ) BUT it
>sounded
>> >very harsh... so I changed the levels down to -3db, and then to -6db, and
>now it
>> >sounds better...
>> >
>> > Isn't that weird?
>>
>> I bet a nickel that if you look at the output with a scope, you will find
>> that your CD player has a linearity problem slightly below 0dBFS. This is
>> sadly very common with consumer players.
>
>You want to really find nonlinearity problems in DACs...generate three tones
>in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say) -1dBFS,

WOW!! wouldn't that be an unfair test of the low pass filters?? I can imagine
the mess recording full power at 19k and 19.5k...

> then mix them
>down at equal levels so the composite wave totals -0.1dBFS. Play that back
>through your DAC, attenuate a few dB, and record the attenuated result into
>a pro-quality sound card. You'll be surprised how much gunk a lot of DACs
>put out.
>
>For DACs, this seems to be a real torture test. Oh, it's a torture test for
>tweeters too, so *don't* play it back through your speakers!
>
>Peace,
>Paul
>
January 11, 2005 11:52:27 PM

Archived from groups: rec.audio.pro (More info?)

On Tue, 11 Jan 2005 07:16:09 -0500, "Arny Krueger" <arnyk@hotpop.com> wrote:

>"siguy" <sjwatt@gmail.com> wrote in message
>news:1105427344.401843.137590@f14g2000cwb.googlegroups.com
>
>> digital can never be perfect, long live the acetate ripping
>> needle!!!!!
>
>Yes, I regret to admit that I just spent a lot of my winter vacation camping
>in the Anza-Barrago (California) and Baja Mexico (Erindera) deserts and
>failed to bring back any cactus needles.
>

If you drop in at my Dads, he'll proudly show you his cactus needle sharpener
kit!!

I'm still looking for a 78 cartridge so I can record his collection of old
records...
Anonymous
January 12, 2005 1:06:41 AM

Archived from groups: rec.audio.pro (More info?)

"Bob" <FlintsTone@Valve.Amps> wrote in message
news:ue09u0l04dnbjejvft2uogk2r9k6kt1930@4ax.com
> On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler"
> <pstamlerhell@pobox.com> wrote:

>> You want to really find nonlinearity problems in DACs...generate
>> three tones in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say)
>> -1dBFS,
>
> WOW!! wouldn't that be an unfair test of the low pass filters?? I
> can imagine the mess recording full power at 19k and 19.5k...

The world is full of converters that will handle this signal, no sweat.
January 12, 2005 2:56:07 AM

Archived from groups: rec.audio.pro (More info?)

On Tue, 11 Jan 2005 22:06:41 -0500, "Arny Krueger" <arnyk@hotpop.com> wrote:

>"Bob" <FlintsTone@Valve.Amps> wrote in message
>news:ue09u0l04dnbjejvft2uogk2r9k6kt1930@4ax.com
>> On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler"
>> <pstamlerhell@pobox.com> wrote:
>
>>> You want to really find nonlinearity problems in DACs...generate
>>> three tones in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say)
>>> -1dBFS,
>>
>> WOW!! wouldn't that be an unfair test of the low pass filters?? I
>> can imagine the mess recording full power at 19k and 19.5k...
>
>The world is full of converters that will handle this signal, no sweat.
>

I guess I'll have to try it! I'll call it the "Krueger" test!
Anonymous
January 12, 2005 3:21:30 AM

Archived from groups: rec.audio.pro (More info?)

On Tue, 11 Jan 2005 18:20:39 GMT, "Paul Stamler"
<pstamlerhell@pobox.com> wrote:

>I'm not entirely sure the problem's in the analog sections. Standard output
>from a DAC at 0dBS is 2Vrms, which is about 5.64Vpp. Most of the analog
>stages run from +/- 15V rails, and such a stage should have no problem with
>5.64Vpp. I would guess, without going inside a player with a scope, that
>what's going on is digital clipping someplace, perhaps in the filtering
>stage.

Lots of interesting responses, too. Not yet mentioned are the big
out-of-band switching transients, and maybe overshoots, that the
summing junction I/V stage has to live with. Comparable in order
of nastiness magnitude with mic preamps, perhaps.

It's a mean world out there, little electrons. Be safe.

Chris Hornbeck
"Conscious that we must have sprung from somewhere, we are
lured to the riddle of our origins." -Malcolm W. Browne
Anonymous
January 12, 2005 4:19:27 AM

Archived from groups: rec.audio.pro (More info?)

On Wed, 12 Jan 2005 12:00:45 +1100, "Phil Allison"
<philallison@tpg.com.au> wrote:

>> I guess the culprit has to be the CD player.
>
>
>
> ** Or the following amplifer input stage is overloading.

It's now a point of honour with you that it ISN'T the CD player's
fault, I take it? :-)

CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm
"Possibly the world's least impressive web site": George Perfect
Anonymous
January 12, 2005 5:15:25 AM

Archived from groups: rec.audio.pro (More info?)

On Tue, 11 Jan 2005 20:52:27 -0500, Bob <FlintsTone@Valve.Amps> wrote:

>I'm still looking for a 78 cartridge so I can record his collection of old
>records...

Maybe check with Mike (IIRC) at:

http://www.esotericsound.com/

who's make a solid gig out of helping folks do just that.

Good transfering,

Chris Hornbeck
"Happiness isn't something you experience; it's something you remember."
-Oscar Levant
Anonymous
January 12, 2005 10:03:01 AM

Archived from groups: rec.audio.pro (More info?)

"Bob" <FlintsTone@Valve.Amps> wrote in message
news:ue09u0l04dnbjejvft2uogk2r9k6kt1930@4ax.com...
> >You want to really find nonlinearity problems in DACs...generate three
tones
> >in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say) -1dBFS,
>
> WOW!! wouldn't that be an unfair test of the low pass filters?? I can
imagine
> the mess recording full power at 19k and 19.5k...

Yeah, but I can also imagine a hot, overcompressed cymbal crash exciting
precisely this sort of distortion.

Peace,
Paul
Anonymous
January 12, 2005 10:03:52 AM

Archived from groups: rec.audio.pro (More info?)

"Arny Krueger" <arnyk@hotpop.com> wrote in message
news:xv6dnffOs4KjCXncRVn-vw@comcast.com...
> "Bob" <FlintsTone@Valve.Amps> wrote in message
> news:ue09u0l04dnbjejvft2uogk2r9k6kt1930@4ax.com
> > On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler"
> > <pstamlerhell@pobox.com> wrote:
>
> >> You want to really find nonlinearity problems in DACs...generate
> >> three tones in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say)
> >> -1dBFS,
> >
> > WOW!! wouldn't that be an unfair test of the low pass filters?? I
> > can imagine the mess recording full power at 19k and 19.5k...
>
> The world is full of converters that will handle this signal, no sweat.

Right -- plus a few that can't. Makes you wonder.

Peace,
Paul
Anonymous
January 12, 2005 10:07:11 AM

Archived from groups: rec.audio.pro (More info?)

"Bob" <FlintsTone@Valve.Amps> wrote in message
news:idb9u0tg93o3qj4b9g9trksujbrbi8if08@4ax.com...
> On Tue, 11 Jan 2005 22:06:41 -0500, "Arny Krueger" <arnyk@hotpop.com>
wrote:
>
> >"Bob" <FlintsTone@Valve.Amps> wrote in message
> >news:ue09u0l04dnbjejvft2uogk2r9k6kt1930@4ax.com
> >> On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler"
> >> <pstamlerhell@pobox.com> wrote:
> >
> >>> You want to really find nonlinearity problems in DACs...generate
> >>> three tones in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say)
> >>> -1dBFS,
> >>
> >> WOW!! wouldn't that be an unfair test of the low pass filters?? I
> >> can imagine the mess recording full power at 19k and 19.5k...
> >
> >The world is full of converters that will handle this signal, no sweat.
> >
> I guess I'll have to try it! I'll call it the "Krueger" test!

Ahem. May I point out that I proposed it up above? Not that it's
particularly new; a similar test was suggested in an article in Audio
Amateur some fifteen years ago. It's very useful for sleuthing out problems
in DACs, ADCs and, for that matter, opamps.

Peace,
Paul
Anonymous
January 12, 2005 10:10:11 AM

Archived from groups: rec.audio.pro (More info?)

"Bob" <FlintsTone@Valve.Amps> wrote in message
news:o j09u0tj4h4eg0d51vv29g1m5s58f1rp5h@4ax.com...
> On Tue, 11 Jan 2005 07:16:09 -0500, "Arny Krueger" <arnyk@hotpop.com>
wrote:
>
> >"siguy" <sjwatt@gmail.com> wrote in message
> >news:1105427344.401843.137590@f14g2000cwb.googlegroups.com
> >
> >> digital can never be perfect, long live the acetate ripping
> >> needle!!!!!
> >
> >Yes, I regret to admit that I just spent a lot of my winter vacation
camping
> >in the Anza-Barrago (California) and Baja Mexico (Erindera) deserts and
> >failed to bring back any cactus needles.
> >
>
> If you drop in at my Dads, he'll proudly show you his cactus needle
sharpener
> kit!!
>
> I'm still looking for a 78 cartridge so I can record his collection of old
> records...

Grado makes one, and many remastering engineers (including the guys at
Smithsonian/Folkways) use a Stanton 500 with various styli.

Peace,
Paul
Anonymous
January 12, 2005 12:25:40 PM

Archived from groups: rec.audio.pro (More info?)

Bob <FlintsTone@Valve.Amps> wrote:
>
>I'm still looking for a 78 cartridge so I can record his collection of old
>records...

The Grado DJ-100 is probably a good start. It is inexpensive and has a
2.7 mil stylus available.

If you have to play worn records, or pre-electric records, or some records
from smaller labels, or you really care about sound quality, you will do a
lot better to use a cartridge with a wide variety of different stylus sizes.
But to start out with, a 2.7 mil one is an okay compromise and won't ruin
any records.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
January 12, 2005 2:04:58 PM

Archived from groups: rec.audio.pro (More info?)

"Bob" <FlintsTone@Valve.Amps> wrote in message
news:idb9u0tg93o3qj4b9g9trksujbrbi8if08@4ax.com
> On Tue, 11 Jan 2005 22:06:41 -0500, "Arny Krueger" <arnyk@hotpop.com>
> wrote:
>
>> "Bob" <FlintsTone@Valve.Amps> wrote in message
>> news:ue09u0l04dnbjejvft2uogk2r9k6kt1930@4ax.com
>>> On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler"
>>> <pstamlerhell@pobox.com> wrote:
>>
>>>> You want to really find nonlinearity problems in DACs...generate
>>>> three tones in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say)
>>>> -1dBFS,
>>>
>>> WOW!! wouldn't that be an unfair test of the low pass filters?? I
>>> can imagine the mess recording full power at 19k and 19.5k...
>>
>> The world is full of converters that will handle this signal, no
>> sweat.
>>
>
> I guess I'll have to try it! I'll call it the "Krueger" test!

The Krueger test is 18 KHz and 20 KHz mixed 1:1 and with peak level 1 dB
below FS. Analysis is a full-band FFT analysis with at least 65K points.
Nonlinear distortion performance can be estimated based on the peak level of
the magnitude of the largest spurious response, but is exactly measured by
the geometric sum of all spurious responses.

Of course, this is not something I made up or invented, just something I
use. So putting my name on it grants me credit that I do not deserve. But,
I'll take it anyway! ;-)
Anonymous
January 12, 2005 2:05:35 PM

Archived from groups: rec.audio.pro (More info?)

"Paul Stamler" <pstamlerhell@pobox.com> wrote in message
news:z04Fd.5187$7N1.524@bgtnsc04-news.ops.worldnet.att.net
> "Bob" <FlintsTone@Valve.Amps> wrote in message
> news:idb9u0tg93o3qj4b9g9trksujbrbi8if08@4ax.com...
>> On Tue, 11 Jan 2005 22:06:41 -0500, "Arny Krueger"
>> <arnyk@hotpop.com> wrote:
>>
>>> "Bob" <FlintsTone@Valve.Amps> wrote in message
>>> news:ue09u0l04dnbjejvft2uogk2r9k6kt1930@4ax.com
>>>> On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler"
>>>> <pstamlerhell@pobox.com> wrote:
>>>
>>>>> You want to really find nonlinearity problems in DACs...generate
>>>>> three tones in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say)
>>>>> -1dBFS,
>>>>
>>>> WOW!! wouldn't that be an unfair test of the low pass filters?? I
>>>> can imagine the mess recording full power at 19k and 19.5k...
>>>
>>> The world is full of converters that will handle this signal, no
>>> sweat.
>>>
>> I guess I'll have to try it! I'll call it the "Krueger" test!
>
> Ahem. May I point out that I proposed it up above? Not that it's
> particularly new; a similar test was suggested in an article in Audio
> Amateur some fifteen years ago. It's very useful for sleuthing out
> problems in DACs, ADCs and, for that matter, opamps.

Paul, it seems like a fine test, and I'm happy to see you get all the
credit.
Anonymous
January 12, 2005 2:06:53 PM

Archived from groups: rec.audio.pro (More info?)

"Paul Stamler" <pstamlerhell@pobox.com> wrote in message
news:sZ3Fd.5170$7N1.3240@bgtnsc04-news.ops.worldnet.att.net
> "Arny Krueger" <arnyk@hotpop.com> wrote in message
> news:xv6dnffOs4KjCXncRVn-vw@comcast.com...
>> "Bob" <FlintsTone@Valve.Amps> wrote in message
>> news:ue09u0l04dnbjejvft2uogk2r9k6kt1930@4ax.com
>>> On Tue, 11 Jan 2005 06:01:14 GMT, "Paul Stamler"
>>> <pstamlerhell@pobox.com> wrote:
>>
>>>> You want to really find nonlinearity problems in DACs...generate
>>>> three tones in CEP, at 9.6kHz, 19kHz and 19.5kHz, each at (say)
>>>> -1dBFS,
>>>
>>> WOW!! wouldn't that be an unfair test of the low pass filters?? I
>>> can imagine the mess recording full power at 19k and 19.5k...
>>
>> The world is full of converters that will handle this signal, no
>> sweat.
>
> Right -- plus a few that can't.

Agreed.

> Makes you wonder.

Not really. There are always people who want to shave every margin that
might be safely shaved, and then a few more.
Anonymous
January 12, 2005 2:06:54 PM

Archived from groups: rec.audio.pro (More info?)

Arny Krueger wrote:

>
>
> Not really. There are always people who want to shave every margin that
> might be safely shaved, and then a few more.


I hate it when they do that to bridges and buildings.
Anonymous
January 12, 2005 2:56:29 PM

Archived from groups: rec.audio.pro (More info?)

"Laurence Payne"
>
>>> No, I think you have a player problem.
>>
>>
>>** Practically zero chance that is the case.
>
>
> So what is the problem?


** Bob's most likely problem is that his test disk has serious distortion.

The other possibility is that his pre-amp following the CD player cannot
accept 2 volt rms without distortion - many older domestic amps were only
designed for 200mV - 500 mV signals on the aux inputs.




.............. Phil
Anonymous
January 12, 2005 2:57:56 PM

Archived from groups: rec.audio.pro (More info?)

"Arny Krueger"
>
>
>> digital can never be perfect, long live the acetate ripping
>> needle!!!!!
>
> Actually, the fault being described is probably on the analog side of the
> converters.


** Only if you include the amplifier following the CD player.




.............. Phil
Anonymous
January 12, 2005 3:08:44 PM

Archived from groups: rec.audio.pro (More info?)

"Arny Krueger" ...
> "Laurence Payne"
>>
>>>>>> No, I think you have a player problem.
>>>>>
>>>>>
>>>>> ** Practically zero chance that is the case.
>>>>
>>>>
>>>> So what is the problem?
>>>
>>> Probably a player problem.
>>
>> So it's what Scott said? :-)
>
> (Putting fireproof suit on)
>
> Yup!
>
> ;-)


** This public fellatio with the arch audiophool Dorsey has to cease Arny.

People will think you have lost your interest in objectivity.




............. Phil
Anonymous
January 12, 2005 4:15:28 PM

Archived from groups: rec.audio.pro (More info?)

"S O'Neill" <nopsam@nospam.net> wrote in message
news:jrqdneFZjIcmxXjcRVn-gA@omsoft.com

> Arny Krueger wrote:
>
>> Not really. There are always people who want to shave every margin
>> that might be safely shaved, and then a few more.

> I hate it when they do that to bridges and buildings.

Particularly if you are standing in, on or under them. Ditto for airplanes.
Anonymous
January 12, 2005 4:15:29 PM

Archived from groups: rec.audio.pro (More info?)

Arny Krueger wrote:
> "S O'Neill" <nopsam@nospam.net> wrote in message
> news:jrqdneFZjIcmxXjcRVn-gA@omsoft.com
>
>
>>Arny Krueger wrote:
>>
>>
>>>Not really. There are always people who want to shave every margin
>>>that might be safely shaved, and then a few more.
>
>
>>I hate it when they do that to bridges and buildings.
>
>
> Particularly if you are standing in, on or under them. Ditto for airplanes.


And especially Fords.
!