opaqueice;363188 Wrote:
Phil, any further progress on sorting this out?
Not yet. Apparently we are in the throes of a global financial crisis
which means my employer expects me to spend silly amounts of time at
work looking for the odd billion pounds lurking behind a filing
cabinet...
I have
Crisis ? What crisis ?
(ah... THAT one...) ^^
--
Themis
SB3 - North Star dac 192 - Denon 3808 - Sonus Faber Grand Piano Domus
Themis's Profile: http://forums.slimdevices.com/member.php?userid=14700
View this thread:
Themis;363616 Wrote:
Crisis ? What crisis ?
(ah... THAT one...) ^^
I have one too... out of single malts! And out of Irish too!!
good to see the thread pop up, even when it's just some chatting ;-)
ciao!
Nick.
--
DeVerm
Phil, any further progress on sorting this out?
--
opaqueice
opaqueice's Profile: http://forums.slimdevices.com/member.php?userid=4234
View this thread: http://forums.slimdevices.com/showthread.php?t=53345
What equipment could be more useful at sea than...a sub! Anyway just put
it on the left hand side of the boat (this is known as a bass port...)
Now I'll be quiet too.
Darren
--
darrenyeats
SB3 / Inguz - Krell KAV-300i (pre bypass) - PMC AB-1
Dell laptop - JVC UX-C30 mini system
darrenyeats;354991 Wrote:
What equipment could be more useful at sea than...a sub! Anyway just put
it on the left hand side of the boat (this is known as a bass port...)
Now I'll be quiet too.
Darren
ouch ouch ouch my head is hurting now :o)
Anyway a very nice looking Blue Jeans Digital
DCtoDaylight;354791 Wrote:
What you really need though, is to convert those sail's into
electrostatics! Imagine hiking out in front of those puppies!
I'll be quiet now Dave
Friends with another boat use a projector to beam DVD playback into
their mainsail while sailing downwind at
DeVerm;355077 Wrote:
Friends with another boat use a projector to beam DVD playback into
their mainsail while sailing downwind at night!
I like that! The ocean going equivalent to the drive in theatre! Pass
the popcorn!
PS, Brilliant Darren!
--
DCtoDaylight
Audiophile wish list: Zero
Another thought: instead of putting it in by-pass mode, can't you load
it with parameters for a flat-response curve? i.e. not modifying the
sound?
This would basically give the same output and I'm suspecting that this
is what they do if you select by-pass mode. But on the other hand,
there might
DeVerm;354506 Wrote:
Another thought: instead of putting it in by-pass mode, can't you load
it with parameters for a flat-response curve? i.e. not modifying the
sound?
This would basically give the same output and I'm suspecting that this
is what they do if you select by-pass mode. But on
DeVerm;354506 Wrote:
glad my boat is beyond anything a tact can fix ;-) The whole hull is
vibrating and relaying the subwoofer action to the world outside ;-)
You need to find a way to break up the standing waves in the hull.
Drilling lots of holes will do the trick
--
cliveb
DeVerm;354506 Wrote:
glad my boat is beyond anything a tact can fix ;-) The whole hull is
vibrating and relaying the subwoofer action to the world outside
If the hull is vibrating, it's damping the energy right? and most
boats I've been in, are hard pressed to find a lot of parallel
opaqueice;354104 Wrote:
Feed the SB3 directly to your DAC. If the square waves are fine, that
proves it's the TACT that's the problem.
Not to mince words, if they haven't they're incompetent (not the
reviewers, the designers).
SB into DAC (no TACT) = perfect squarewave.
--
Phil
DeVerm;354105 Wrote:
Phil, you had a square on that test-cd. Connect a cd-player with s/pdif
to the tact and see what happens with the square signal direcly from
CD. That also eliminates the lame comments like the SB is to blame.
I should really read up on DSP's... I didn't realize the
opaqueice;354104 Wrote:
Feed the SB3 directly to your DAC. If the square waves are fine, that
proves it's the TACT that's the problem.
Not to mince words, if they haven't they're incompetent (not the
reviewers, the designers).
Since you've never tested the TacT RCS 2.2X, this like most
CPC;354132 Wrote:
Since you've never tested the TacT RCS 2.2X, this like most of your
statements, Not to mince words, proves nothing.
Has Phil Leigh contacted TacT's designer(Boz. [EMAIL PROTECTED]) on
this issue?
What mode(2.2 or 2.0) is he operating the RCS in?
What FS is the RCS
Phil Leigh;354128 Wrote:
SB into DAC (no TACT) = perfect squarewave.
Done. It's the TACT.
CPC;354132 Wrote:
Since you've never tested the TacT RCS 2.2X, this like most of your
statements, Not to mince words, proves nothing.
I said that *if* the TACT designers hadn't at some point tested
CPC;354132 Wrote:
Since you've never tested the TacT RCS 2.2X, this like most of your
statements, Not to mince words, proves nothing.
Has Phil Leigh contacted TacT's designer(Boz. [EMAIL PROTECTED]) on
this issue?
What mode(2.2 or 2.0) is he operating the RCS in?
What FS is the RCS
Phil Leigh;354320 Wrote:
If (big IF!) I'm understanding things correctly, the ASRC alogrithm is
inside the AD1896 chips not in the TACT firmware/OS.
I see.
So then it's either defective hardware or some other kind of software
bug in the TACT. And defective hardware seems strange... I
opaqueice;354368 Wrote:
I see.
So then it's either defective hardware or some other kind of software
bug in the TACT. And defective hardware seems strange... I would
think if there was something wrong with the chip it would do more than
add some moderate harmonic distortion.
This is
seanadams;353797 Wrote:
It it went through ASRC then it has in fact been affected by the analog
domain. ASRC deals with two non-synchronized PCM signals, so variances
in the frequencies of the input relative to the output (an analog
quantity) will affect the data that is calculated - that's
Just eliminated another variable:
1) 16-bit vs 24-bit files - no difference
2) downloaded another test tone generator (NCH) and that produces
identical results to Audacity.
I've done lots of googling and can find no reference to the AD1896 ASRC
chip misbehaving itself in this way. That only
Phil Leigh;353999 Wrote:
What really bugs me is the asymmetry of the display. If this was an
analogue circuit you'd think oh yeah, the power supply is sagging on
one leg... but in the digital space this makes no sense to me!
Is the TACT forum saying anything? Surely their engineers tested
opaqueice;354008 Wrote:
Is the TACT forum saying anything? Surely their engineers tested
squarewaves...
Good question - so far nothing much other than suggestions that I
should upgrade my power supply (already done it) and I should
concentrate on getting low-jitter into the TACT. Also some
Phil Leigh;354010 Wrote:
Good question - so far nothing much other than suggestions that I should
upgrade my power supply (already done it) and I should concentrate on
getting low-jitter into the TACT. Also some subtle comments about the
SB not being a suitably low-jitter source for the TACT
Phil, you had a square on that test-cd. Connect a cd-player with s/pdif
to the tact and see what happens with the square signal direcly from
CD. That also eliminates the lame comments like the SB is to blame.
I should really read up on DSP's... I didn't realize the signal goes
through analog
The TACT has a digital output - in fact that's all mine has!.
Problem is I no longer have any PC cards with spdif-in
You are right to observe that the signal never leaves the digital
domain except theoretically within the ASRC chips.
I guess the bottom line is that in bypass mode the TACT is
Phil Leigh;353521 Wrote:
I guess the bottom line is that in bypass mode the TACT is not
bit-perfect.
I think that must be the explanation.
That can't be the bottom line - this is a *major* bug if in fact it's
what we think it is. That waveform is distorted at easily audible
levels, which
opaqueice;35 Wrote:
Another thought - does the TACT have a digital output? If so, try
recording it playing that 1kHz square wave using a soundcard digital
input. That will give you a file which has never been in the analogue
domain and hence cannot be affected by jitter (unless it's so
Phil - my copy of audacity can generate 30kHz+ tones. Maybe you have an
old version? Or maybe you need to change the sample rate?
Phil Leigh;352649 Wrote:
Some other fora have implied this might be the result of jitter folding
back into the analogue domain as harmonic distortion... but
Another thought - does the TACT have a digital output? If so, try
recording it playing that 1kHz square wave using a soundcard digital
input. That will give you a file which has never been in the analogue
domain and hence cannot be affected by jitter (unless it's so bad it's
causing bit errors,
DeVerm;352213 Wrote:
Same here, sorry Phil. Will start a separate thread next time and stop
off-topic posts here.
Actually, I have been thinking about your problem. My observation from
your photo's is that the tops from the 5th-7th harmonics are clearly
missing from the square wave. As
Some more results:
changing the sampling rate of the generated waveforms from 44.1 to 48
makes no difference to any results! I can't go to 96 because the SB3
doesn't support it!
Below roughly 750 Hz the squarewaves coming out of the TACT and SB look
pretty much the same (it's quite hard to
Phil Leigh;352432 Wrote:
Some more results:
changing the sampling rate of the generated waveforms from 44.1 to 48
makes no difference to any results!
Well, then there's something wrong in either the test-setup or the
TACT. I come to that conclusion because at 48 we should have up to 24
kHz
Phil Leigh;352422 Wrote:
20kHz sine - looks like a perfect sine
hmmm I had hoped it would not. This is evidence that we're not looking
for a frequency related artifact.
21Khz sine - Audacity can't go over 20kHz!!!
double hmmm... we really need a 22.050 kHz sine in 48 kHz sample rate
to
OK - I will post some pics tomorrow and try the 12k/48 wave.
Thanks for your feedback. This is looking increasingly like a bug in
the ASRC algorithm, at least to me!
Some other fora have implied this might be the result of jitter folding
back into the analogue domain as harmonic distortion...
DeVerm wrote:
DCtoDaylight;351968 Wrote:
Look at it this way, everybody has taken an aspirin at some point in
their life, but one pill won't reduce your risk of stroke. Low
dosages, over a long time, will. So a short term ABX test would
produce one result, a long term ABX would produce
pablolie;351985 Wrote:
Are you measuring the right interface given the fact that what you are
trying to explain is the different sound to your ears? Are you really,
*REALLY* sure that that is nthe only interface that has possibly
changed? Are there no other possible interactions between
DeVerm;352008 Wrote:
You are right that you have control and can listen to each sample as
long as you want. But that is not the way it is done: samples are
mostly 10-20 seconds long and intervals between two samples are often
0.5-1 second.
Evidence for mostly? I've done quite a few blind
I'm gonna split up in multiple posts a bit because it's just to diverse
to include it all into 1 post;
opaqueice;352132 Wrote:
Evidence for mostly? I've done quite a few blind tests, and some were
done with quick switches, some with long. Same goes with the ones I've
read about - in fact I
DeVerm;352167 Wrote:
5-30s samples
My conclusion: in audio ABX testing, short 5-30s samples are used. The
reason is that they follow the CCIR recommendations from 1978. I do
believe that you use longer samples but I am referring to large scale
testing incl. the Muraoka et al. 1978;
opaqueice;352132 Wrote:
Again, you're attacking a straw man. I said nothing of the sort. There
are all sorts of ways in which research can be wrong, and lying is dead
last on the list. It's quite rare - but wrong research is very, very
common.
Well... okay, I'll go with that although you
Wombat;352175 Wrote:
The fact these samples are that short are simply cause of copyright
laws. You can´t post samples longer.
Look at the samples, lots of them are sounds, no commercial song
recordings. Also, the samples used in the Muraoka et al. 1978; Plenge
et al. 1979 studies were so
:o(
My thread has been polluted (sob).
Can anyone with a scope and a TACT replicate my findings?
My analogue scope is 60Mhz. Hardly state of the art I know but is its
bandwidth too low to study spdif signals? (should I ever return to the
original question in the thread title!)
Cheers
Phil
--
At least you posted to pages where some of the samples are found by me
myself :)
I offered these short samples cause they were long enough to show
isolated problems with specific mp3 encoders.
And yes, as i remember we used short samples also to avoid fatiguing
when testing more versions against
Wombat;352195 Wrote:
Edit: Sorry Phil for going Off-Topic. Even me that writes seldom here
couldn´t overread the lng posts of these people on their mission.
's okay Wombat - you weren't the first :o)
--
Phil Leigh
You want to see the signal path BEFORE it gets onto a CD/vinyl...it
I will personally stop polluting this thread. After all, I don't care
about convincing anybody about any facts, this was not the point of my
post -it was purely informative. Facts are the same whether some people
believe in them or not, we're all adults, and each one of us has his own
experience
Themis;352208 Wrote:
I will personally stop polluting this thread. After all, I don't care
about convincing anybody about any facts, this was not the point of my
post -it was purely informative. Facts are the same whether some people
believe in them or not, we're all adults, and each one of
Same here, sorry Phil. Will start a separate thread next time and stop
off-topic posts here.
Actually, I have been thinking about your problem. My observation from
your photo's is that the tops from the 5th-7th harmonics are clearly
missing from the square wave. As the fundamental was 1 kHz,
DeVerm;352213 Wrote:
Same here, sorry Phil. Will start a separate thread next time and stop
off-topic posts here.
Actually, I have been thinking about your problem. My observation from
your photo's is that the tops from the 5th-7th harmonics are clearly
missing from the square wave. As
DeVerm;352167 Wrote:
Well, I just spent another 30 minutes searching the net for long
samples and I didn't find a single one! So I stick with my statement.
Here is what I find:
snip
My conclusion: in audio ABX testing, short 5-30s samples are used.
You regard an internet search for
Another thought:
Your scope should have a test-square-wave output on the front. It's
analog and you should calibrate your probes on it using the little
adjustment-screw (capacitor).
Also, something that Mr. O observed already
(http://forums.slimdevices.com/showpost.php?p=348946postcount=46) but
opaqueice;352224 Wrote:
You regard an internet search for copyright-constrained ABX samples as
evidence that most ABX testing uses short samples, and from there
conclude that the ABX protocol is invalid? Don't be silly.
It is true that there is evidence that some differences are easier to
opaqueice;352224 Wrote:
You regard an internet search for copyright-constrained ABX samples as
evidence that most ABX testing uses short samples, and from there
conclude that the ABX protocol is invalid? Don't be silly.
continued here:
Phil Leigh;352232 Wrote:
Mr O - with the greatest of respect (and that is NOT a phrase I use
lightly) - could I beg you to apply your brain power to my question and
to take your discussions on the ABX issue with Nick to another thread.
I need both of your different wisdoms applied to my
DCtoDaylight;351670 Wrote:
The odd thing is that it does sound good with this filter engaged, but
perhaps the fact that the extra harmonics are going to be well above
20kHz means they aren't harmful because I can't hear them?Well, if your
speakers *can* reproduce these harmonics, then
Themis;351688 Wrote:
Well, if your speakers *can* reproduce these harmonics, then perhaps you
can't hear them, but beware :
http://jn.physiology.org/cgi/content/full/83/6/3548
Wow, you found it! ;-) well, this removes any doubt on this research
being done or not when I quoted a reference to
DeVerm;351702 Wrote:
Also, this should put all the pro blind-test arguments on a somewhat
lower amplitude as this research proves that it's flawed. Neil Young
was right after all, ha!
What do you mean? This research -was- a blind test - anything else
would obviously be worthless. Part of
opaqueice;351880 Wrote:
What do you mean? This research -was- a blind test - anything else
would obviously be worthless.
Yes, but I was comparing it with the much praised ABX testing and the
software utils for that like in foobar. They use short samples and
repetitions. There are many
opaqueice;351880 Wrote:
Another comment is that one of the experimenters is a manufacturer of
speakers with supertweeters. That's a clear conflict of interest and
automatically casts doubt on the results, especially when they go
against a century of other research.I understand your doubts.
DeVerm;351942 Wrote:
Yes, but I was comparing it with the much praised ABX testing and the
software utils for that like in foobar.
But that's more or less precisely the format that was used here! If
you don't agree, please explain how it was different in any significant
way.
They use
Themis;351958 Wrote:
But this is a scientific research published in the equally scientific
Journal of Neurophysiology. These people don't play with their own
reputation when publishing results. And no unverified results can exist
in such scientific publications. This is not a marketing
DeVerm;351942 Wrote:
Yes, but I was comparing it with the much praised ABX testing and the
software utils for that like in foobar. They use short samples and
repetitions. There are many audiophiles that state that even though
they don't hear the difference during abx testing, they will
Phil Leigh;346309 Wrote:
Yes I know I am sad.
Anyway, I was goofing around yesterday and I tried to look at the spdif
o/p from the SB. I have a Philips/Fluke 60Mhz scope of 80's vintage
which works perfectly AFAIK. However, I couldn't get a nice stable
trace. Timebase autoset to 50nS. Is
opaqueice;351963 Wrote:
But that's more or less precisely the format that was used here!
[...]
That's an oft-repeated audiophile canard, and it's just false. Have
you ever [...]
You are right that you have control and can listen to each sample as
long as you want. But that is not the way
DCtoDaylight;351968 Wrote:
Right but there's nothing anywhere that say's ABX testing needs to be
short term.
Indeed, one can test by listening to a sample as long as one wants...
--but they don't do that--.
Medical ABX tests routinely run for months and sometimes years, in order
to
So the possible problems with the TACT up sampling got me to thinking
about an up sampler I use (Assemblage D2D-2), and as I posted on the
Humble pie thread, I was happy not to see any apparent issues with it's
upsampled square wave.
So onto another toy, this time an Esoteric DV50 universal
Very interesting. RDOT, a made up marketing term, appears to be
interpolating between samples without any memory of the previous
samples. They cite the Fluency theory which also appears to be
complete maketroid nonsense - esoteric indeed!
While at first glance one might think it makes a better
I told you I wasn't expecting this!
And I agree, it's creating a lot of harmonic information (distortion?)
based on no real information. The test cd I'm using only has a couple
of sine waves, and this square wave. I need to find or create
something with more options so I can try and figure out
At lower frequencies of course it would have minimal impact, because
straight lines between samples is not a bad approximation. But I'm just
guessing at what this filter does based on the square wave.
--
seanadams
Timothy Stockman;350823 Wrote:
I guess one could hook the primary of the transformer through a larger
pad betweeh the TXP and TXN terminals, rather than TXP and ground. See
appendix A of the Crystal Semiconductor datasheet. My coax output
circuit is copied from there. I have not tested
ar-t;351343 Wrote:
I would still use a cap
Well, it is a moot point. We have been debating the finer points of an
interface which never went into production for an obsolete device which
was discontinued by the manufacturer 4 years ago. And, as the OP's
interest was in viewing the S/PDIF
No, because as a consultant, I get paid for that sort of stuff. I won't
get paid by anyone if they knew I gave it away for free.
This has nothing to do with you or your designs. I am sorry if you got
that impression. I am just trying to steer guys trying to roll their
own from making all the
opaqueice;350846 Wrote:
Can you link to the thread there? I'm curious to know what they say.
Certainly I will... as soon as they let me join!
--
Phil Leigh
You want to see the signal path BEFORE it gets onto a CD/vinyl...it
ain't what you'd call minimal...SB3+Stontronics PSU - Altmann
Timothy Stockman;350517 Wrote:
S/PDIF is manchester encoded. An effect of this is to eliminate the DC
component. Although I ordered a transformer and put a footprint for it
when I made the PCB layout, I never built one with the coax parts
populated (I always used Toslink in my prototype
Returning vaguely to the original topic...
Further research into the TACT Squarewave phenomena has lead me to
conclude (or should I say agree with Sean!) that what is happening is
an artifact of the multiple ASRC processes within the TACT.
I'm going to see if I can get any answers from the
Timothy Stockman;350520 Wrote:
In a past life I was a broadcast engineer. All of the older AM
broadcast transmitters I remember, most were Collins, did NOT pass the
DC current to the final RF stage through the modulation transformer;
there was a blocking cap in series with the secondary.
ar-t;350663 Wrote:
You use a DC blocking cap on your AM transmitters. Why do you think that
you don't need one here?
PatI guess one could hook the primary of the transformer through a larger
pad betweeh the TXP and TXN terminals, rather than TXP and ground. See
appendix A of the Crystal
Phil Leigh;350666 Wrote:
Returning vaguely to the original topic...
Further research into the TACT Squarewave phenomena has lead me to
conclude (or should I say agree with Sean!) that what is happening is
an artifact of the multiple ASRC processes within the TACT.
I'm going to see if I
ar-t;349995 Wrote:
Anyone notice what kind of transformer it is? Anyone..hm?
Sorry to disappoint you but I never used one for digital audio so I
wouldn't know. But it is labeled as a digital audio transformer which
sounds right for using it here...
Too bad he lets DC go through
DeVerm;350323 Wrote:
Sorry to disappoint you but I never used one for digital audio so I
wouldn't know. But it is labeled as a digital audio transformer which
sounds right for using it here...
You mean through it's primary winding? I don't know the CS8405A chip
either so wouldn't know
DeVerm;350323 Wrote:
But it sounds like you know the transformer used ;-)
cheers,
Nick
I know *all* of the transformers.
Yes, caps are an issue. But not as much as DC current through a
teeny-tiny ferrite care that saturates -very easily-.
The larger core ones are not useful for this
ar-t;349995 Wrote:
Anyone notice what kind of transformer it is? Anyone..hm?
Too bad he lets DC go through it. Oh, well.
Pat
S/PDIF is manchester encoded. An effect of this is to eliminate the DC
component. Although I ordered a transformer and put a footprint for it
when I
Timothy Stockman wrote:
I had the most years of experience with a Collins 21A 5KW transmitter
at WBAA radio. The modulation transformer (a Thordarson True
Fidelity model) and modulation reactor were so big and heavy that they
sat, along with the 3 power transformers of the 3 phase 8.8KV plate
pfarrell;350525 Wrote:
Timothy Stockman wrote:
I had the most years of experience with a Collins 21A 5KW transmitter
at WBAA radio. The modulation transformer (a Thordarson True
Fidelity model) and modulation reactor were so big and heavy that
they
sat, along with the 3 power
Timothy Stockman;349756 Wrote:
http://proxy1.fielddiagnostics.com/~tps/i2s/
The schematic in that link shows a S/PDIF transmitter on both coax and
toslink. The coax output has a transformer and guess what: the BNC
connector (or RCA) is -not- connected to ground, just like I tried to
explain
Anyone notice what kind of transformer it is? Anyone..hm?
Too bad he lets DC go through it. Oh, well.
Pat
--
ar-t
http://www.analogresearch-technology.net
ar-t's Profile:
OK - here are some more pics:
In all cases, the upper trace is from the SB3 analogue output and the
lower trace is from the analogue output of my MF DAC with the TACT RCS
connected digitally in the the s/pdif chain and set to bypass (so all
it should be doing is resampling.
Sorry about the
seanadams;349663 Wrote:
In defense of SB3's noisy sine: a scope doesn't tell you the frequency
of that noise content. Although it does have its share of audible noise,
most of what you see on the scope is out of band noise (far above 20KHz)
as an artifact of delta sigma modulation. Of
In defense of SB3's noisy sine: a scope doesn't tell you the frequency
of that noise content. Although it does have its share of audible noise,
most of what you see on the scope is out of band noise (far above 20KHz)
as an artifact of delta sigma modulation. Of course, higher end DACs
would also
Phil Leigh;349652 Wrote:
Anyway, you can see that the sinewaves via the TACT is pretty perfect
but the squarewaves have that added distortion.
You really can't conclude anything from that sinewave. My hypothesis
was that the TACT is adding harmonic distortion, but that would be very
hard
Well, I used to work on audio amps in the repair shop 30 years ago and
excessive harmonic distortion (odd or even order) was easily visible on
a scope to me - usually. We always used to use a sig gen sine wave to
test this. But I'm talking about the sort of rather obvious distortion
you'd get in
Phil,
Both square and sine waves are 1 kHz, right? But the square has that 21
kHz harmonic because of the 11 tops we counted. So I think it would make
sense to test sine waves on all those harmonics, not just the
fundamental, starting with the 19 and 21 kHz !! This is where any
frequency
DeVerm;349713 Wrote:
Anyway, I would be ready by now to put the TACT on eBay ;-)A bit TOO
obvious... :)
--
Themis
SB3 - North Star dac 192 - Denon 3808 - Sonus Faber Grand Piano Domus
Themis's Profile:
Themis;349721 Wrote:
A bit TOO obvious... :)
It's not going on eBay - if I turn it off my system sounds... boring.
I'm just curious to get to the bottom of why the squarewave is so odd.
It sounds fine!
--
Phil Leigh
You want to see the signal path BEFORE it gets onto a CD/vinyl...it
ain't
DeVerm;349713 Wrote:
Phil,
Both square and sine waves are 1 kHz, right? But the square has that 21
kHz harmonic because of the 11 tops we counted. So I think it would make
sense to test sine waves on all those harmonics, not just the
fundamental, starting with the 19 and 21 kHz !! This is
Themis;349735 Wrote:
I meant, that Nick seemed ready to buy it, and his advice looked a bit
too obvious to me. :)
(at least, that's the way I understood^^)
And you should certainly NOT sell it, (for its use) it's a famous
digital gear.
Ah - yes
ha ha - I hadn't thought of it like that!
More interesting than looking at the manchester-encoded S/PDIF signal is
looking at the I2S signal either before the S/PDIF transmitter chip or
after an S/PDIF receiver. I made the web page below a few years ago
just after XM released the XMPCR. You can see the I2S data and word
clock waveforms
Phil Leigh;349730 Wrote:
Nick,
I have the scope, a good sig gen, a bench PSU and a very nice Fluke
multimeter and an SPL meter - that's it!
I'll have to think about your LP filter idea. I don't have one - or a
spectrum analyser or distortion meter.
I'll try higher freq sine waves
opaqueice;349759 Wrote:
I don't think sine waves are going to show much - it's really hard to
see the difference between the top and middle trace in my plot, even
though there's quite significant distortion there (enough to be easily
audible).
I would try different frequencies and
1 - 100 of 155 matches
Mail list logo
