A good way to avoid misunderstanding is to be direct and honest; that is, say what you mean and mean what you say. In my experience if you feel the need for a private side channel, that implies that your public statements are either not honest or poorly framed.
Scott was perfectly right to speak up and correct a common misconception or simple mistake. If you had some other intent WRT another poster, then it might have served you better to ignore Scott's response, at least until you elicited the response you were looking for from whoever you were addressing. You can hardly express surprise if you say something incorrect in a public forum, and someone points out your error. You should not feel the need to explain your intentions; the fact that you do feel that need suggests that you have been deliberately hiding your intentions. That is probably a bad idea in a public forum.
Sorry if I am off base here. There is (was?) another member here who always responded to public comments with private messages explaining conspiracy theories about how other members here were out to suppress him, and why. That was a very unpleasant experience and your comments about concealed intentions brought that memory back. Again, if Scott's comments distract from your "long game" then just ignore them and keep playing your game.
I respect Mark's long term goal concerning how subtle the things are that we can/can't hear. He is being far more reasonable that some that have come before.
I should also note that I have been introduced to a lot of music via this site and we should not forget that listening to music is the whole reason we do this (or should be). And whilst some of Scott's collection is borderline disturbing I appreciate every opportunity to be challenged 
.
(aside I have noted to the wife that if Radio 3, the uk classical station, doesn't sometimes play things that cause me to change channel, then they are not doing their job right).
.(aside I have noted to the wife that if Radio 3, the uk classical station, doesn't sometimes play things that cause me to change channel, then they are not doing their job right).
But still blocks/attempts to shame into silence those inconvenient to his project. So is it really that much more reasonable?
I actually did a test to look at ringing in a HF loudspeaker line. I used a one hertz square wave through a 10 uF capacitor and loaded with a 5 ohm resistor as the source. Feeding a JBL 2413 compression driver through 100 meters of cable.
There was ringing at the compression driver end. It was about 10 dB down from the peak and was about 9 rings before fading into the noise. Frequency about 400,000 hertz. Placing a zobel network to maintain constant 8. Ohm impedance at the driver ave a few dB of attenuation but it still rang.
One suggestion has been to add a low pass filter that will raise the load impedance to match the driving line.
So those of you using long cables with hearing to 400,000 hertz have a problem.
No sign of the ringing on the send end. (Whith the high source impedance.)
Wire used was West Penn Wire 25225 12 gauge 200+ stand count twisted paid with a plenum insulation.
At home not able to post the image.
There was ringing at the compression driver end. It was about 10 dB down from the peak and was about 9 rings before fading into the noise. Frequency about 400,000 hertz. Placing a zobel network to maintain constant 8. Ohm impedance at the driver ave a few dB of attenuation but it still rang.
One suggestion has been to add a low pass filter that will raise the load impedance to match the driving line.
So those of you using long cables with hearing to 400,000 hertz have a problem.
No sign of the ringing on the send end. (Whith the high source impedance.)
Wire used was West Penn Wire 25225 12 gauge 200+ stand count twisted paid with a plenum insulation.
At home not able to post the image.
I measured a number of RCA connections a number of years ago. The calculations give about 35 Ohms IF the dielectric is air and the female connection for the centerpin has zero wall thickness. Measured on a tdr with 20 pS resolution and a 75 Ohm air line (I was being serious) they were all below 30 Ohms. The discontinuity was about 100 pS.
For SPDIF this is pretty inconsequential since risetimes under 5 nS are an EMI problem not needed.
However there was a length issue early on with AES. The original implementation was low source Z and high sink Z. Some lengths just did not work. I can see audiophiles taking this story and projecting Armageddon with digital cable of the wrong length. When its all magic you need a Shaman to escort you across the river Styx.
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For SPDIF this is pretty inconsequential since risetimes under 5 nS are an EMI problem not needed.
However there was a length issue early on with AES. The original implementation was low source Z and high sink Z. Some lengths just did not work. I can see audiophiles taking this story and projecting Armageddon with digital cable of the wrong length. When its all magic you need a Shaman to escort you across the river Styx.
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True your situation baffles me, honestly it is upsetting but I can't control things that probably happen in part to some impulsive feelings at a point in time. I have not noticed the shame into silence aspect, I will try to be more aware of that in the future.
Right now listening to one of my only old RCA shaded dog classics, LSC-2435 Heifetz Sibelius Violin Concerto, CSO. If someone wants to tell me my <$1000 total setup sounds like shite and how could I listen to it they are welcome to, but it sounds fine to me. Somehow "it sounds fine to me" has some unexpected weight, that is not intended like Bill I could care less what anyone thinks about what I do and don't like.
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I wouldn't worry about it too much. He's said "shame on you" and took too much exception to my language a few times for what is my direct and probably overly-aggressive form of skepticism. More of a way of expressing his frustration.
(and to be entirely fair, I am likewise frustrated oftentimes and not on my best behavior)
Enjoy the music, and happy Father's Day to all you dads out there.
(and to be entirely fair, I am likewise frustrated oftentimes and not on my best behavior)
Enjoy the music, and happy Father's Day to all you dads out there.
I Try to avoid the digital ports in consumer gear due to Z mismatches and potential for jitter at receiving end with slower Tr.
To put some numbers to it...... from my TEK Inc TDR slide rule.......
a 50 Ohm source and 50 Ohm cable with produce a +50% reflected voltage ( 6dB) with 150 ohm load.
a 75 Ohm system...... -6dB with 225 Ohm load. So, yes, Demian into a high Z load, it wont work well if at all. .
This is with 50-75 Ohm connectors, of course. And Toshlink F.O. ports have similar reflections at connector. Signal atten. losses are only about 0.1dB per connector/port so Z match is the more important issue.
I still have my TEK TDR system.... I just have not taken the time to TDR what I am using.
THx-RNMarsh
To put some numbers to it...... from my TEK Inc TDR slide rule.......
a 50 Ohm source and 50 Ohm cable with produce a +50% reflected voltage ( 6dB) with 150 ohm load.
a 75 Ohm system...... -6dB with 225 Ohm load. So, yes, Demian into a high Z load, it wont work well if at all. .
This is with 50-75 Ohm connectors, of course. And Toshlink F.O. ports have similar reflections at connector. Signal atten. losses are only about 0.1dB per connector/port so Z match is the more important issue.
I still have my TEK TDR system.... I just have not taken the time to TDR what I am using.
THx-RNMarsh
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My daughter will be finished with high school in the next couple of weeks. A friend of hers (not a close friend) died on Thursday, apparently from an opioid overdose. Hold your children close and let them know they are loved. (Apparently this girl was troubled and addicted to synthetic opioids, which she was able to buy on line, which I find shocking.)
Do you get it? I can't believe the lack of understanding around this from people who should know better. It's hilarious in a way.
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I also did some.jitter measurements with Toslink at 192 KHz and 48 KHz. With current gen receivers 20 pS jitter is typical and often less. I would describe jitter as a solved problem. The receivers are all less than $5 and some are around $1 in smaller quantity.
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Sent from my LG-H811 using Tapatalk
If I may change the subject for a bit, the DacMagicPlus came today. There is a review of its immediate predecessor over at Stereophile: https://www.stereophile.com/budgetcomponents/cambridge_audio_azur_dacmagic_da_converter/index.html
The newer version offers more sample rates, has a volume knob on the front, and may have improvements in USB jitter rejection, something that manufacturer talked about in the Stereophile review.
Anyway, I just got finished comparing it to the DAC-1 using one of Pavel's new test files.
Short summary of the review is that it will be returned for refund.
Slightly longer version is that it sounds nice. Okay, I would say for casual listening. Not as suitable for mixing or mastering as the DAC-1 though. Why not? Less HF clarity, punch, and distinction between different instrument sounds. And more HF smearing, masking, and distortion compared to DAC-1. It doesn't have a lot of the bad things though, but enough of them so that I don't really have an application for it at the moment.
How can all that be given the specs look so nice? I wish I knew. I wouldn't have ordered it if I could tell by looking at the specs that it would substantially not sound as good as DAC-1. I really wanted it to be a winner too. It's seems about time for a DAC the caliber of DAC-1 to become available at lower cost. Oh, well. Have to contact the seller now.
The newer version offers more sample rates, has a volume knob on the front, and may have improvements in USB jitter rejection, something that manufacturer talked about in the Stereophile review.
Anyway, I just got finished comparing it to the DAC-1 using one of Pavel's new test files.
Short summary of the review is that it will be returned for refund.
Slightly longer version is that it sounds nice. Okay, I would say for casual listening. Not as suitable for mixing or mastering as the DAC-1 though. Why not? Less HF clarity, punch, and distinction between different instrument sounds. And more HF smearing, masking, and distortion compared to DAC-1. It doesn't have a lot of the bad things though, but enough of them so that I don't really have an application for it at the moment.
How can all that be given the specs look so nice? I wish I knew. I wouldn't have ordered it if I could tell by looking at the specs that it would substantially not sound as good as DAC-1. I really wanted it to be a winner too. It's seems about time for a DAC the caliber of DAC-1 to become available at lower cost. Oh, well. Have to contact the seller now.
If you have some time before it has to be returned, burn it in for a week or two,
and see if it improves.
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