Subject: Re: TDS passive harmonic enhancer
Date: Thu, 27 Aug 1998 19:17:54 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/27 at 19:17:53, BLAYER@SMTP {blayer@uswest.net} wrote:
Hi Travis,
>So, I read the stuff in the Music Direct catalogue, I think I was in the
>"Resource Learning Center", (heh-heh) and I wondered, too. But, did you
>account for the different amplifier input impedances likely encountered
>during measurements and listening tests, did you insert the device between
>the preamp and amp? Transformers have a nasty (and natural) tendency to
>ring whenever they are improperly loaded.
Yes. It was discovered (no big mystery) that the unit exhibited it's most
pronounced characteristic when the Zin was low and the Zout was relatively
high. However, we must conclude that the ringing characteristic was the
primary design goal of the creator, because the unit does not display any
other notable electronic phenomena. It's just a pair of transformers.
Strengthening this, is the marketing claim that the unit 'enhances' or
'replaces' upper harmonics. Therefore, (IMO) to optimize it's effect is in
keeping with the manufacturer's goals.
Contrary to this, is the lack of manufacturer's reccomendation to acheive
these 'optimal' conditions with specified impedances. Ah, what do they
know?
-b
Subject: ASOG Web Page Updates
Date: Thu, 27 Aug 1998 20:50:19 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/27 at 20:50:19, WB6RHQ@SMTP {wb6rhq@loop.com} wrote:
Dear ASOG Members,
The next time you're on-line, swing by the AGOG page. We now have some
excellent pictures from Travis Franklin and Jerry Seigel. Thank you,
Travis and Jerry.
If anyone would like to see their pictures on the page too, please let
me know. I can even scan them for you.
Best regards,
mark gilmore
Subject: More TDS chit-chat
Date: Fri, 28 Aug 1998 7:56:32 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/28 at 07:56:32, B.LAYER@SMTP {b.layer@vikingelectronics.com} wrote:
Hi All,
Travis' question about input/output loading on the TDS affecting performace
got me thinking. There is also an active version of the same unit, and I
can guess just what is active...
Buffer stages: Hi-Zin to low-Zin to keep the primary side tied down, and
hi-Zout to low-Zout to keep the secondary impedance high, so that the unit
can ring as designed. It would be interesting to get an active unit, and
calculate the impedances presented to the transformers.
Bill Layer
Sales Technician
----------------------------------
Viking Electronics, Inc.
Hudson, WI. U.S.A
715.386.8861 (ext. 210)
----------------------------------
"Telecommunications Solutions for the 21st Century"
Subject: RE: Preamp needed??
Date: Fri, 28 Aug 1998 8:16:51 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/28 at 08:16:50, JERRY$SE@SMTP {Jerry_Seigel@jdedwards.com} wrote:
Bob,
Passive pre? They work well with A-S amps due to the high input impedance of
the amps - at least the M60. Try to use one with a shunt volume control as
they seem to beat the expensive Penny & Giles or Alps "Black Beauty" style
by a wide margin. Electronic Visionary Systems is a good source for either a
custom pot or the whole box. I'm still looking for an active device that is
better than my passive (total cost ~$400, which looks good on paper, but
delivers superior results).
The EAR 834P is very good, as others have said. I was bothered by the "dark
sound", mentioned in the Stereophile ad and... BEWARE: TWEAK AHEAD...found
that by raising the value of R1 and R101, the preamp sounded much more
neutral. I think the cartridge used in the review, a Koetsu Urushi, may be
like my Benz Ruby, in that the Benz likes higher loads that the EAR's 500
ohms. In direct comparisons with a Nagra PL-P (just the phono section), the
EAR's midrange and treble is of equal quality, and its bass is a bit loose
and fat. Considering the EAR is $900 vs. $9500 for the Nagra, the EAR is an
outstanding bargain, and it uses only 3 tubes! Next stop: AHT-DM.
I'm glad summer is winding down so I can listen to music for more than '2
sides' before my sound room gets too warm.
Happy Listening,
Jerry
> -----Original Message-----
> From: Atma-Sphere@ManicReader.com [SMTP:Atma-Sphere@ManicReader.com]
> Sent: Tuesday, August 25, 1998 10:43 AM
> To: Atma-Sphere@ManicReader.com
> Subject: Preamp needed??
>
> On 1998/08/25 at 09:42:51, JOKKER@SMTP {jokker@motorsims.com} wrote:
>
> Just wanted to say hello.
>
> As Mark indicated, I'm in the process of updating my whole audio system.
> While I'm not abandoning analog source just yet, I see it coming. I just
> added a Pioneer Elite DVD player to my theater system and I was greatly
> pleased with the promise of the new digital formats. 96/24 is real. I've
> been grinding on a decision that perhaps someone here can help me with. I
> have been planning to use the Casablanca as a preamp. Digital input will
> be all in the David/Casablanca. I've wondered how a great tube amp like
> the Atma-sphere would interface with a solid state device like the
> Casablanca? I'm obviously going to try , but would appreciate any advise
> from the group. As for analog, are there any phono stages with enough gain
> for the occasionally vinyl session?
>
> Or is a preamp necessary?
>
> Thanks for inviting me aboard.
>
> Bob McCarthy
>
>
>
> ----------------[ Uuencoded File Attachment: NONAME01.HTML
> ]---------------- << File: NONAME01.HTML >>
Subject: A Vacation...
Date: Fri, 28 Aug 1998 9:11:44 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/28 at 09:11:43, MARK.GIL@SMTP {mark.gilmore@smtek.com} wrote:
Dear ASOG members,
I will be on vacation until next Wednesday, but I will be hanging out close
to home. Since I've been receiving so many good pictures from some of you,
I like to get them on the ASOG page as soon as I can. If you need to send me
email, or more pictures before next Wednesday, please send them to my home
address at wb6rhq@loop.com.
This picture stuff is a lot of fun. I plan to post some of my own this
weekend too.
Best regards,
mark
Subject: Re: RAD, MAN
Date: Sat, 29 Aug 1998 18:19:13 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/29 at 18:19:12, ASEK@SMTP {asek@uswest.net} wrote:
A late entry to this tired thread:
The Theta Miles is a one-box CD player with claimed ability to preserve both
frequency response and phase near the upper limit imposed by Nyquist. It
sounds better than any other digital source I've heard, including much more
expensive Mark Levinson and Krell separates, even in the same demonstration
setup. I can't say whether an ultimate turntable setup would be better, but
I'll guess one would have to pay two to ten times its price of $2500 to find
out. There are a few good old CDs (such as Canyon by Paul Winter) but most
recorded before 1996 sound terrible. A good recent CD that preserves the space
of the recording venue with a large orchestra is Chailly and the Royal
Concertgebouw's Mahler 5 (London 289 458 860-2).
My take on the topic is that we are just recently getting properly-made compact
discs and playback equipment on the market. Incompetent execution is not a
reason to condemn the format.
Atma-Sphere@ManicReader.com wrote:
> On 1998/08/27 at 08:46:56, HITSBBOP@SMTP {hitsbbop@flash.net} wrote:
>
> >Date: Tue, 25 Aug 1998 18:20:52 -0500
> >To: asog
> >From: Travis Franklin
> >Subject: RAD, MAN
> >Cc:
> >Bcc:
> >X-Attachments:
> >
> > I told myself, I said "Self, don't you get into this fray", but, like, I
> >would take my own advice, AS IF!
> > Hey Bob, welcome to ASOG. I'm glad my initiation wasn't quite this
> >intense. So, like I have MA-1's hooked up to the M-L re-Quests from an
> >Adcom (gasp) 565 pre-amp and things sound pretty darn good (plus I have a
> >decent phone pre-amp built in, HAH). But back to the fray. You and I
> >both know that there are good and bad sounding CD's, and, that there are
> >good and bad sounding LP's. So, we all hear differently. Is that a big
> >deal? No, it's called a reality check. I think Atma-Sphere does a pretty
> >good job of capturing the essence of digital, whatever that is. Maybe it
> >captures it too good for some people. I guess I'm too busy listening to
> >MUSIC to limit myself to the lousy selection on LP. One has to get one's
> >priorities in order, does not one?
> >
> > All for one,
> >
> >
> > Travis
> >
>
> Travis Franklin
> hitsbbop@flash.net
Subject: Re: RAD, MAN
Date: Sat, 29 Aug 1998 21:26:19 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/29 at 21:26:18, HITSBBOP@SMTP {hitsbbop@flash.net} wrote:
>On 1998/08/29 at 18:19:12, ASEK@SMTP {asek@uswest.net} wrote:
>
>A late entry to this tired thread:
>
>The Theta Miles is a one-box CD player with claimed ability to preserve both
>frequency response and phase near the upper limit imposed by Nyquist. It
>sounds better than any other digital source I've heard, including much more
>expensive Mark Levinson and Krell separates, even in the same demonstration
>setup. I can't say whether an ultimate turntable setup would be better, but
>I'll guess one would have to pay two to ten times its price of $2500 to find
>out. There are a few good old CDs (such as Canyon by Paul Winter) but most
>recorded before 1996 sound terrible. A good recent CD that preserves the
>space
>of the recording venue with a large orchestra is Chailly and the Royal
>Concertgebouw's Mahler 5 (London 289 458 860-2).
>
>My take on the topic is that we are just recently getting properly-made
>compact
>discs and playback equipment on the market. Incompetent execution is not a
>reason to condemn the format.
>
>Atma-Sphere@ManicReader.com wrote:
>
>> On 1998/08/27 at 08:46:56, HITSBBOP@SMTP {hitsbbop@flash.net} wrote:
>>
>> >Date: Tue, 25 Aug 1998 18:20:52 -0500
>> >To: asog
>> >From: Travis Franklin
>> >Subject: RAD, MAN
>> >Cc:
>> >Bcc:
>> >X-Attachments:
>> >
>> > I told myself, I said "Self, don't you get into this fray", but, like, I
>> >would take my own advice, AS IF!
>> > Hey Bob, welcome to ASOG. I'm glad my initiation wasn't quite this
>> >intense. So, like I have MA-1's hooked up to the M-L re-Quests from an
>> >Adcom (gasp) 565 pre-amp and things sound pretty darn good (plus I have a
>> >decent phone pre-amp built in, HAH). But back to the fray. You and I
>> >both know that there are good and bad sounding CD's, and, that there are
>> >good and bad sounding LP's. So, we all hear differently. Is that a big
>> >deal? No, it's called a reality check. I think Atma-Sphere does a pretty
>> >good job of capturing the essence of digital, whatever that is. Maybe it
>> >captures it too good for some people. I guess I'm too busy listening to
>> >MUSIC to limit myself to the lousy selection on LP. One has to get one's
>> >priorities in order, does not one?
>> >
>> > All for one,
>> >
>> >
>> > Travis
>> >
>>
>> Travis Franklin
>> hitsbbop@flash.net
This thread grows thin indeed.
Is this deja-vu all over again or what? So let's see, CD's after '96 are
starting to sound good and LP's after ? were starting to sound good 'till
digital came along and then they started to sound really good and....
Well, what can I say? Here we go again. Just when 44.1 is being figured
out we have to step up(?) to another "better" format. What is it that
keeps us from doing a format RIGHT and enjoying it. I think I know the
answer to that one and I don't like it very much. Maybe THIS TIME I'll
stop buying the newest format in hopes of you-know-what. I still think, as
this email certainly implies, that we have not refined the current CD sound
as far as it can go, and I think it can go pretty far. Thoughts?
Far Out,
Travis
P.S. The Chailly Mahler 5th better be superior MUSICALLY than the two
Bernstein's and the old Solti, both of which hug my heart.
Travis Franklin
hitsbbop@flash.net
Subject: Digital again
Date: Mon, 31 Aug 1998 7:51:21 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/31 at 07:51:20, JOKKER@SMTP {jokker@motorsims.com} wrote:
I had a most pleasant conversation with the leader (Ralph) last week regarding digital audio. We had to have spoken for a good 30+ minutes on this subject. A couple of things Ralph said struck home.
Frequency- Ralph made the point digital is much more promising when it meets the "instrument" spec which is 10X the highest audible frequency. I may be slightly misquoting here. A friend of mine who's an EE backed this up and said something to the effect you can't accurately sample a square wave unless you have 10X the samples of the frequency. He somewhat lost me at this point but the jest of both conversations are 44khz is entirely inadequate unless all the sound energy is in the lower octaves. Ralph also totally discredited the methodology that the 44khz standard was set under.
By extension then, 200khz would be the appropriate standard for full frequency audio produced digitally. This implies that two of the newer proposed suggestions, namely SACD (200khz) and DVD-Audio (192khz) have a chance to be a real improvement. Note that this is not 96/24 DVD-video bases audio. I've been playing around with 96/24 and its a real improvement over CD. I went back and listened to the pieces that sounded great and in all cases contained a surplus of energy in the lower and midrange areas. I would guess only the harmonics reached way up there.
Other issues were storage. CD's, DVD's and other digital disk storage media do not have long shelf lives. I have come across this with Laserdisc audio with disks delaminating. The glues that bind do not bind forever. Vinyl can last a long time as we all know. Probably not forever but longer than CD.
I do know that digital can be exact as long as we don't use loosy compression techniques. The new Meridan compression technology has real promise here. I am still concerned with the accuracy of the D/A conversion process but maybe time can solve this issue as did phono cartridge makers for vinyl. Clocking errors can be the final frontier, but buffering and reclocking can largely resolve the jitter problem.
It was a enjoyable conversation and I'm not retiring vinyl for now.
Bob
----------------[ Uuencoded File Attachment: NONAME01.HTML ]----------------
I had a most pleasant conversation with the leader (Ralph) last week
regarding digital audio. We had to have spoken for a good 30+ minutes on
this subject. A couple of things Ralph said struck home.
Frequency- Ralph made the point digital is much more promising when it meets
the "instrument" spec which is 10X the highest audible frequency. I may be
slightly misquoting here. A friend of mine who's an EE backed this up and
said something to the effect you can't accurately sample a square wave
unless you have 10X the samples of the frequency. He somewhat lost me at
this point but the jest of both conversations are 44khz is entirely
inadequate unless all the sound energy is in the lower octaves. Ralph also
totally discredited the methodology that the 44khz standard was set under.
By extension then, 200khz would be the appropriate standard for full
frequency audio produced digitally. This implies that two of the newer
proposed suggestions, namely SACD (200khz) and DVD-Audio (192khz) have a
chance to be a real improvement. Note that this is not 96/24 DVD-video bases
audio. I've been playing around with 96/24 and its a real improvement over
CD. I went back and listened to the pieces that sounded great and in all
cases contained a surplus of energy in the lower and midrange areas. I would
guess only the harmonics reached way up there.
Other issues were storage. CD's, DVD's and other digital disk storage media
do not have long shelf lives. I have come across this with Laserdisc audio
with disks delaminating. The glues that bind do not bind forever. Vinyl can
last a long time as we all know. Probably not forever but longer than CD.
I do know that digital can be exact as long as we don't use loosy
compression techniques. The new Meridan compression technology has real
promise here. I am still concerned with the accuracy of the D/A conversion
process but maybe time can solve this issue as did phono cartridge makers
for vinyl. Clocking errors can be the final frontier, but buffering and
reclocking can largely resolve the jitter problem.
It was a enjoyable conversation and I'm not retiring vinyl for now.
Bob
Subject: Re: Digital again
Date: Mon, 31 Aug 1998 11:34:28 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/31 at 11:34:26, TRE@SMTP {tre@ncplus.com} wrote:
Atma-Sphere@ManicReader.com wrote:
>
> On 1998/08/31 at 07:51:20, JOKKER@SMTP {jokker@motorsims.com} wrote:
>
> I had a most pleasant conversation with the leader (Ralph) last week regarding digital audio. We had to have spoken for a good 30+ minutes on this subject. A couple of things Ralph said struck home.
>
> Frequency- Ralph made the point digital is much more promising when it meets the "instrument" spec which is 10X the highest audible frequency. I may be slightly misquoting here. A friend of mine who's an EE backed this up and said something to the effect you can't accurately sample a square wave unless you have 10X the samples of the frequency. He somewhat lost me at this point but the jest of both conversations are 44khz is entirely inadequate unless all the sound energy is in the lower octaves
>
> By extension then, 200khz would be the appropriate standard for full frequency audio produced digitally. This implies that two of the newer proposed suggestions, namely SACD (200khz) and DVD-Audio (192khz) have a chance to be a real improvement. Note that this is not 96/24 DVD-video bases audio. I've been playing around with 96/24 and its a real improvement over CD. I went back and listened to the pieces that sounded great and in all cases contained a surplus of energy in the lower and midrange
>
> Other issues were storage. CD's, DVD's and other digital disk storage media do not have long shelf lives. I have come across this with Laserdisc audio with disks delaminating. The glues that bind do not bind forever. Vinyl can last a long time as we all know. Probably not forever but longer than CD.
>
> I do know that digital can be exact as long as we don't use loosy compression techniques. The new Meridan compression technology has real promise here. I am still concerned with the accuracy of the D/A conversion process but maybe time can solve this issue as did phono cartridge makers for vinyl. Clocking errors can be the final frontier, but buffering and reclocking can largely resolve the jitter problem.
>
> It was a enjoyable conversation and I'm not retiring vinyl for now.
>
> Bob
>
> ----------------[ Uuencoded File Attachment: NONAME01.HTML ]----------------
>
> I had a most pleasant conversation with the leader (Ralph) last week
> regarding digital audio. We had to have spoken for a good 30+ minutes
> on this subject. A couple of things Ralph said struck home.
>
> Frequency- Ralph made the point digital is much more promising when it
> meets the "instrument" spec which is 10X the highest audible
> frequency. I may be slightly misquoting here. A friend of mine who's
> an EE backed this up and said something to the effect you can't
> accurately sample a square wave unless you have 10X the samples of the
> frequency. He somewhat lost me at this point but the jest of both
> conversations are 44khz is entirely inadequate unless all the sound
> energy is in the lower octaves. Ralph also totally discredited the
> methodology that the 44khz standard was set under.
>
> By extension then, 200khz would be the appropriate standard for full
> frequency audio produced digitally. This implies that two of the newer
> proposed suggestions, namely SACD (200khz) and DVD-Audio (192khz) have
> a chance to be a real improvement. Note that this is not 96/24
> DVD-video bases audio. I've been playing around with 96/24 and its a
> real improvement over CD. I went back and listened to the pieces that
> sounded great and in all cases contained a surplus of energy in the
> lower and midrange areas. I would guess only the harmonics reached way
> up there.
>
> Other issues were storage. CD's, DVD's and other digital disk storage
> media do not have long shelf lives. I have come across this with
> Laserdisc audio with disks delaminating. The glues that bind do not
> bind forever. Vinyl can last a long time as we all know. Probably not
> forever but longer than CD.
>
> I do know that digital can be exact as long as we don't use loosy
> compression techniques. The new Meridan compression technology has
> real promise here. I am still concerned with the accuracy of the D/A
> conversion process but maybe time can solve this issue as did phono
> cartridge makers for vinyl. Clocking errors can be the final frontier,
> but buffering and reclocking can largely resolve the jitter problem.
>
> It was a enjoyable conversation and I'm not retiring vinyl for now.
>
> Bob
I had an old Audio mag from the mid 60's that decribed the Bell Labs
digital recording and gave their conclusion that for it to be "Hi-Fi"
you need a sampling rate 10x the highest freq to be sampled. I lost the
mag. When ever I quote this to anyone they laugh. Oh well.
Tre'
Subject: Re: Digital again
Date: Mon, 31 Aug 1998 16:31:09 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/31 at 16:31:07, BBB@SMTP {bbb@castle.net} wrote:
Hi Bob,
I have to disagree what you have been said. It has been mathematically
proven that the minimum sampling frequency required in order to
"perfectly" re-construct the original time domain signal is twice that
of the target signal. I just do not see why people still have doubt
about that, just like someone still doubt 1+1=2.
The problem here is that two assumptions went wrong ( similar to some
soc. ideas ::)):
1. the ear only can hear upto to 20KHz. this is wrong, wrong wrong!!
2. All the DA/AD conversion has negl. residue sum error. It is not true
for any commercial product. ( When I was working for NASA, I had chance
to experience some customized cost no objective convertor/filters, they
are so true to the original signal...) Plus, the time sequence reference
is not perfect for most commercial digital gears which distorts the
sampling space at first place.
200KHz sampling frequency sure helps, but how about my ear can feel
150Khz? And higher sampling freq. requires more accurate time reference,
Uhm - commercially, may not so!
I have to say Best LP today is better than the best 16bits/44Hz CD. But
LP is not perfect neither. I know the sound of violin from any LPs are
not true for my own experience, I can bet on a spectrum analysis on
this. We have to strive for the better for our own sake, let's promote
better affortable digital sources and ditigal playback system! Do not be
so negative! Looking forward instead of backward! I know, I know, I
sound like JFK now.
I want an "All Mozart" ticket right now. "You pay for what you get"
Ben Yang
Atma-Sphere@ManicReader.com wrote:
> On 1998/08/31 at 07:51:20, JOKKER@SMTP {jokker@motorsims.com} wrote:
>
> I had a most pleasant conversation with the leader (Ralph) last week regarding digital audio. We had to have spoken for a good 30+ minutes on this subject. A couple of things Ralph said struck home.
>
> Frequency- Ralph made the point digital is much more promising when it meets the "instrument" spec which is 10X the highest audible frequency. I may be slightly misquoting here. A friend of mine who's an EE backed this up and said something to the effect you can't accurately sample a square wave unless you have 10X the samples of the frequency. He somewhat lost me at this point but the jest of both conversations are 44khz is entirely inadequate unless all the sound energy is in the lower octaves. Ralph also totally discredited the methodology that the 44khz standard was set under.
>
> By extension then, 200khz would be the appropriate standard for full frequency audio produced digitally. This implies that two of the newer proposed suggestions, namely SACD (200khz) and DVD-Audio (192khz) have a chance to be a real improvement. Note that this is not 96/24 DVD-video bases audio. I've been playing around with 96/24 and its a real improvement over CD. I went back and listened to the pieces that sounded great and in all cases contained a surplus of energy in the lower and midrange areas. I would guess only the harmonics reached way up there.
>
> Other issues were storage. CD's, DVD's and other digital disk storage media do not have long shelf lives. I have come across this with Laserdisc audio with disks delaminating. The glues that bind do not bind forever. Vinyl can last a long time as we all know. Probably not forever but longer than CD.
>
> I do know that digital can be exact as long as we don't use loosy compression techniques. The new Meridan compression technology has real promise here. I am still concerned with the accuracy of the D/A conversion process but maybe time can solve this issue as did phono cartridge makers for vinyl. Clocking errors can be the final frontier, but buffering and reclocking can largely resolve the jitter problem.
>
> It was a enjoyable conversation and I'm not retiring vinyl for now.
>
> Bob
>
> ----------------[ Uuencoded File Attachment: NONAME01.HTML ]----------------
>
> I had a most pleasant conversation with the leader (Ralph) last week
> regarding digital audio. We had to have spoken for a good 30+ minutes
> on this subject. A couple of things Ralph said struck home. Frequency-
> Ralph made the point digital is much more promising when it meets the
> "instrument" spec which is 10X the highest audible frequency. I may be
> slightly misquoting here. A friend of mine who's an EE backed this up
> and said something to the effect you can't accurately sample a square
> wave unless you have 10X the samples of the frequency. He somewhat
> lost me at this point but the jest of both conversations are 44khz is
> entirely inadequate unless all the sound energy is in the lower
> octaves. Ralph also totally discredited the methodology that the 44khz
> standard was set under. By extension then, 200khz would be the
> appropriate standard for full frequency audio produced digitally. This
> implies that two of the newer proposed suggestions, namely SACD
> (200khz) and DVD-Audio (192khz) have a chance to be a real
> improvement. Note that this is not 96/24 DVD-video bases audio. I've
> been playing around with 96/24 and its a real improvement over CD. I
> went back and listened to the pieces that sounded great and in all
> cases contained a surplus of energy in the lower and midrange areas. I
> would guess only the harmonics reached way up there. Other issues were
> storage. CD's, DVD's and other digital disk storage media do not have
> long shelf lives. I have come across this with Laserdisc audio with
> disks delaminating. The glues that bind do not bind forever. Vinyl can
> last a long time as we all know. Probably not forever but longer than
> CD. I do know that digital can be exact as long as we don't use loosy
> compression techniques. The new Meridan compression technology has
> real promise here. I am still concerned with the accuracy of the D/A
> conversion process but maybe time can solve this issue as did phono
> cartridge makers for vinyl. Clocking errors can be the final frontier,
> but buffering and reclocking can largely resolve the jitter
> problem. It was a enjoyable conversation and I'm not retiring vinyl
> for now. Bob
Subject: Re: Digital again
Date: Mon, 31 Aug 1998 19:28:40 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/08/31 at 19:28:39, TRE@SMTP {tre@ncplus.com} wrote:
Atma-Sphere@ManicReader.com wrote:
>
> On 1998/08/31 at 16:31:07, BBB@SMTP {bbb@castle.net} wrote:
>
> Hi Bob,
> I have to disagree what you have been said. It has been mathematically
> proven that the minimum sampling frequency required in order to
> "perfectly" re-construct the original time domain signal is twice that
> of the target signal. I just do not see why people still have doubt
> about that, just like someone still doubt 1+1=2.
>
You are assuming that the 20kc is always a sine wave.
In the second edition of the audiocyclopedia when talking about the
freq.
responce needed to reproduce 20-20kc Tremaine says because of sum and
difference tones a responce up to 200kc is needed.
The problem here is that two assumptions went wrong ( similar to some
> soc. ideas ::)):
> 1. the ear only can hear upto to 20KHz. this is wrong, wrong wrong!!
You are Right Right Right. In fact the deaf can "hear" 30-35kc through
the bones in there heads.
> 2. All the DA/AD conversion has negl. residue sum error. It is not true
> for any commercial product. ( When I was working for NASA, I had chance
> to experience some customized cost no objective convertor/filters, they
> are so true to the original signal...) Plus, the time sequence reference
> is not perfect for most commercial digital gears which distorts the
> sampling space at first place.
>
> 200KHz sampling frequency sure helps, but how about my ear can feel
> 150Khz? And higher sampling freq. requires more accurate time reference,
> Uhm - commercially, may not so!
>
> I have to say Best LP today is better than the best 16bits/44Hz CD. But
> LP is not perfect neither. I know the sound of violin from any LPs are
> not true for my own experience, I can bet on a spectrum analysis on
> this. We have to strive for the better for our own sake, let's promote
> better affortable digital sources and ditigal playback system! Do not be
> so negative! Looking forward instead of backward! I know, I know, I
> sound like JFK now.
>
> I want an "All Mozart" ticket right now. "You pay for what you get"
>
> Ben Yang
>
> Atma-Sphere@ManicReader.com wrote:
>
> > On 1998/08/31 at 07:51:20, JOKKER@SMTP {jokker@motorsims.com} wrote:
> >
> > I had a most pleasant conversation with the leader (Ralph) last week regarding digital audio. We had to have spoken for a good 30+ minutes on this subject. A couple of things Ralph said struck home.
> >
> > Frequency- Ralph made the point digital is much more promising when it meets the "instrument" spec which is 10X the highest audible frequency. I may be slightly misquoting here. A friend of mine who's an EE backed this up and said something to the effect you can't accurately sample a square wave unless you have 10X the samples of the frequency. He somewhat lost me at this point but the jest of both conversations are 44khz is entirely inadequate unless all the sound energy is in the lower octav
> >
> > By extension then, 200khz would be the appropriate standard for full frequency audio produced digitally. This implies that two of the newer proposed suggestions, namely SACD (200khz) and DVD-Audio (192khz) have a chance to be a real improvement. Note that this is not 96/24 DVD-video bases audio. I've been playing around with 96/24 and its a real improvement over CD. I went back and listened to the pieces that sounded great and in all cases contained a surplus of energy in the lower and midrang
> >
> > Other issues were storage. CD's, DVD's and other digital disk storage media do not have long shelf lives. I have come across this with Laserdisc audio with disks delaminating. The glues that bind do not bind forever. Vinyl can last a long time as we all know. Probably not forever but longer than CD.
> >
> > I do know that digital can be exact as long as we don't use loosy compression techniques. The new Meridan compression technology has real promise here. I am still concerned with the accuracy of the D/A conversion process but maybe time can solve this issue as did phono cartridge makers for vinyl. Clocking errors can be the final frontier, but buffering and reclocking can largely resolve the jitter problem.
> >
> > It was a enjoyable conversation and I'm not retiring vinyl for now.
> >
> > Bob
> >
> > ----------------[ Uuencoded File Attachment: NONAME01.HTML ]----------------
> >
> > I had a most pleasant conversation with the leader (Ralph) last week
> > regarding digital audio. We had to have spoken for a good 30+ minutes
> > on this subject. A couple of things Ralph said struck home. Frequency-
> > Ralph made the point digital is much more promising when it meets the
> > "instrument" spec which is 10X the highest audible frequency. I may be
> > slightly misquoting here. A friend of mine who's an EE backed this up
> > and said something to the effect you can't accurately sample a square
> > wave unless you have 10X the samples of the frequency. He somewhat
> > lost me at this point but the jest of both conversations are 44khz is
> > entirely inadequate unless all the sound energy is in the lower
> > octaves. Ralph also totally discredited the methodology that the 44khz
> > standard was set under. By extension then, 200khz would be the
> > appropriate standard for full frequency audio produced digitally. This
> > implies that two of the newer proposed suggestions, namely SACD
> > (200khz) and DVD-Audio (192khz) have a chance to be a real
> > improvement. Note that this is not 96/24 DVD-video bases audio. I've
> > been playing around with 96/24 and its a real improvement over CD. I
> > went back and listened to the pieces that sounded great and in all
> > cases contained a surplus of energy in the lower and midrange areas. I
> > would guess only the harmonics reached way up there. Other issues were
> > storage. CD's, DVD's and other digital disk storage media do not have
> > long shelf lives. I have come across this with Laserdisc audio with
> > disks delaminating. The glues that bind do not bind forever. Vinyl can
> > last a long time as we all know. Probably not forever but longer than
> > CD. I do know that digital can be exact as long as we don't use loosy
> > compression techniques. The new Meridan compression technology has
> > real promise here. I am still concerned with the accuracy of the D/A
> > conversion process but maybe time can solve this issue as did phono
> > cartridge makers for vinyl. Clocking errors can be the final frontier,
> > but buffering and reclocking can largely resolve the jitter
> > problem. It was a enjoyable conversation and I'm not retiring vinyl
> > for now. Bob
Subject: What did Fourier say?
Date: Tue, 1 Sep 1998 7:07:24 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/09/01 at 07:07:23, B.LAYER@SMTP {b.layer@vikingelectronics.com} wrote:
Hi All,
I'm not a mathematics expert, but I don't recall anything about the 2*F
sampling rate being able to properly re-construct the waveform; only the
frequency of the sample.
Someone once suggested that the original purpose of the Fourier system was
to sample bottles on a production, which is not by any means a purely
analog application. Agreed that the bottles can have an unlimited number of
positions on the line, but not that position in any way reflects on size or
shape of the bottle (the bottle is either there or it isn't, unlike a
musical waveform...)
Bill Layer
Sales Technician
----------------------------------
Viking Electronics, Inc.
Hudson, WI. U.S.A
715.386.8861 (ext. 210)
----------------------------------
"Telecommunications Solutions for the 21st Century"
Subject: RE: What did Fourier say?
Date: Tue, 1 Sep 1998 8:06:23 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/09/01 at 08:06:23, JERRY$SE@SMTP {Jerry_Seigel@jdedwards.com} wrote:
Greetings,
Just for fun, I 'scoped the output of my Sony XA7ES CD player with a HP
50mHz scope. Sine waves look nice and smooth up to about 3kHz. From there on
up, it's not as pretty, and it gets worse with increasing frequency.
2X or 10X? The tolerance level will be different for different people. But I
think the experience with 44.1kHz CDs indicates that for the next
generation, we should demand the least-compromised system instead of the
least-common-denominator acceptable system. My vote would go with 10x.
$0.02. (Make that 1 1/2 cents. The stock market...)
Jerry
Denver
> -----Original Message-----
> From: Atma-Sphere@ManicReader.com [SMTP:Atma-Sphere@ManicReader.com]
> Sent: Tuesday, September 01, 1998 8:07 AM
> To: Atma-Sphere@ManicReader.com
> Subject: What did Fourier say?
>
> On 1998/09/01 at 07:07:23, B.LAYER@SMTP {b.layer@vikingelectronics.com}
> wrote:
>
> Hi All,
>
> I'm not a mathematics expert, but I don't recall anything about the 2*F
> sampling rate being able to properly re-construct the waveform; only the
> frequency of the sample.
>
> Someone once suggested that the original purpose of the Fourier system was
> to sample bottles on a production, which is not by any means a purely
> analog application. Agreed that the bottles can have an unlimited number
> of
> positions on the line, but not that position in any way reflects on size
> or
> shape of the bottle (the bottle is either there or it isn't, unlike a
> musical waveform...)
>
>
>
>
> Bill Layer
> Sales Technician
>
>
> ----------------------------------
> Viking Electronics, Inc.
> Hudson, WI. U.S.A
> 715.386.8861 (ext. 210)
>
> ----------------------------------
>
> "Telecommunications Solutions for the 21st Century"
Subject: Re: What did Fourier say?
Date: Tue, 1 Sep 1998 15:06:39 -0700
From: Atma-Sphere@ManicReader.com
Organization: SMTEK
To: Atma-Sphere@ManicReader.com
On 1998/09/01 at 15:06:38, HARPER@SMTP {harper@q3-consulting.com} wrote:
I rather think that milk bottle production lines hadn't been invented
when Fourier invented his transform. In any case what it says is
very simply that any repeating waveform can be represented as the
sum of harmonically-related sine waves, of the form:
sigma ai sin(omega it + pi)
For example (and pertinently) a square wave is the sum of gradually
decreasing odd harmonics (I forget the actual coefficients). Given
a set of samples, it is straightforward to do the transform. Spice
and my software scope both do it if you ask them.
The relevance is that Nyquist's theorem applies individually to
all of the individual components of the square wave. Thus a 10kHz
square wave still has significant harmonics way beyond what the
44 kHz sampling can do anything with, and indeed these harmonics must
be ruthlessly suppressed at the sampling stage if they are not to
wreak havoc (due to "aliasing"). There is a good backgrounder on all
this somewhere, although I don't remember the URL.
Now, if orthodoxy is to be believed, the human ear can't detect those
harmonics either, and so the fact that they are suppressed is irrelevant.
There are people who claim otherwise. They may be right, too. Who
knows. I guess you could test it by computer-generating two waveforms,
one a true 10kHz square wave, and the other stopping at the 2nd
harmonic, and see if people can tell the difference (given a high
rate sound card, obviously).
What IS clear is that 44kHz sampling introduces substantial phase
distortion at the higher audio frequencies, and that this may well
have an effect on things like imaging.
John
At 07:07 01-09-98 -0700, you wrote:
>On 1998/09/01 at 07:07:23, B.LAYER@SMTP {b.layer@vikingelectronics.com}
wrote:
>
>Hi All,
>
>I'm not a mathematics expert, but I don't recall anything about the 2*F
>sampling rate being able to properly re-construct the waveform; only the
>frequency of the sample.
>
>Someone once suggested that the original purpose of the Fourier system was
>to sample bottles on a production, which is not by any means a purely
>analog application. Agreed that the bottles can have an unlimited number of
>positions on the line, but not that position in any way reflects on size or
>shape of the bottle (the bottle is either there or it isn't, unlike a
>musical waveform...)
>
>
>
>
>Bill Layer
>Sales Technician
>
>
>----------------------------------
>Viking Electronics, Inc.
>Hudson, WI. U.S.A
>715.386.8861 (ext. 210)
>
>----------------------------------
>
>"Telecommunications Solutions for the 21st Century"
>