Yes, I have thought to do that also. But anyone can do that. Can't they? Well maybe not with a sound card(?)
-RNM
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Moving right along.... When Doug Self introduced HF thru the PS he found it did increase THD in his amplifier. I am making an assumption, from experience, that introducing it at the amp input will do same.
Now, some want to pretend the level at the CD player output of the HF remains at -60dB. But if you add the 20dB or whatever of the following amp/PA it is more like -40dB level thru the amp to speaker.
What you can argue is that under DBLT no one on earth will hear it. Your mantra.
I leave that to others to listen for themselves.
I also suggested that if an amp getting these HF signals reproduced them at low distortion, there would be no problem in audio. That is more likely with a CFA IMO.
I may get around to doing various amp susceptibility/THD tests to this HF but listening for now is good enough for me.
Bottom line -- If you want to be sure it isnt affecting the amp or the tweeter and the sound... be sure you have a reconstruction filter.
THx-RNMarsh
Now, some want to pretend the level at the CD player output of the HF remains at -60dB. But if you add the 20dB or whatever of the following amp/PA it is more like -40dB level thru the amp to speaker.
What you can argue is that under DBLT no one on earth will hear it. Your mantra.
I leave that to others to listen for themselves.
I also suggested that if an amp getting these HF signals reproduced them at low distortion, there would be no problem in audio. That is more likely with a CFA IMO.
I may get around to doing various amp susceptibility/THD tests to this HF but listening for now is good enough for me.
Bottom line -- If you want to be sure it isnt affecting the amp or the tweeter and the sound... be sure you have a reconstruction filter.
THx-RNMarsh
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You mean the filter in post #76902? OK so you don't mean CD i.e. 44.1/16. CD players don't have analog inputs. You can't fix the output of a Red Book CD in response to a computer generated square wave as used by reviewers. Neither of those articles implies anything else.
A question, has anyone seen a picture of a 1kHz square wave (first 20 harmonics only) added with arbitrary phase to make a result with less overshoot?
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Data would be nice. Pavel didn't seem to see any effect with his electronics.
Of course, that's 1964 stuff, but the question you originally raised was will the low level HF from noise shaping have an effect on downstream components?
It's helpful, when using dB to state the reference level (e.g., dBV, dBU, dBSPL) just to keep the numbers straight.
You havent been following close attention to what I have done? I recorded square wave signal thru MasterLink machine's ADC onto CD and played back same CD on same machine's DAC.
THx-RNMarsh
Yes, are you doing this at 44.1kHz sampling rate, your recorder can do it's thing as a non-Red Book system at 24/96? The Gibb's ringing at 44.1 is around 22.05 the filter you show has no attenuation at that frequency.
Repeat the exercise and burn a CD you can play on any CD player.
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You have more test equipment than most of us! And a built filter. I have neither at the moment.
Richard
This is strange. I have yet to see a single CD player in the mid/low price range that is build without a post DAC analog LP filter (at least a copy from DAC’s application data sheet)
Thanks for the link. I didn’t know that the “zero order hold” has an effect of a sinc function (an LP filter)
The “active equalizer” shown in Figure 7a is a simple 6dB/oct LP filter (with the values shown –3db at 1.8MHz) and is not an analog filter whose frequency response is approximately equal to the inverse of the sinc function. What do I miss?
I am afraid it’s your enthusiasm taking over again
George
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Sounds like a good parlor trick but not meaningful of much except synthetic as a source. If your goal is real sounds in real spaces then you do need to look at a composite system.
Until recently only HDCD looked at the whole system with the filtering on both ends matched.
MQA seems to take the same plan. MQA looks a lot like an HDCD clone with hidden DRM.
Sent from my SGH-M919 using Tapatalk
Until recently only HDCD looked at the whole system with the filtering on both ends matched.
MQA seems to take the same plan. MQA looks a lot like an HDCD clone with hidden DRM.
Sent from my SGH-M919 using Tapatalk
I am not sure what you want to know.
If anyone remembers, I am interested in how the whole chain responds.... not one piece at a time. This is a Mastering machine. It records and plays back. It records a digitised master file and Redbook CD copies are made from that master file. Then you/me/we play it back.
There is a lot of HF after 20Kz which may or may not be dealt with in your playback machine. Just because it is shown in the mfr data sheet is no quarantine it was done that way. And, I know some do have that extra post-DAC filter. I assume it isnt desireable to have HF because of potential to increase distortion further down the chain. Filter it.... like the CD32 does. I had to add one.
What you see are real measured data from analog output of that process on that machine (ML-9600). Before and after.
When you add the analog output filter, you get a cleaner representation of the original input (back at the ADC input) and also no HF hash. That is all.
I do not understand the direction others want to take this. If your machine has clean (no HF) in output, good for you.
Like I said and tested..... even Blue-Ray/3D DVD/CD player's analog out also has a lot of HF on its analog output.
So, I am not so sure the filtering is universally used by any means.
-------------------------------------------------------
[FWIW --- the filter I made included the knowledge of the input Z of the BenchMark and was designed with the aid of the network analyzer] And, just running the SQ wave thru the ADC and DAC of BenchMark mfr shows no HF and no artifacts at the analog output. And no file storage, Redbook spec, CD burner involved. Still at USD $4000 msrp. These would be what I would use in critical situations along with perhaps the i7 computer and burner. The good sh*t.
THx-RNMarsh
If anyone remembers, I am interested in how the whole chain responds.... not one piece at a time. This is a Mastering machine. It records and plays back. It records a digitised master file and Redbook CD copies are made from that master file. Then you/me/we play it back.
There is a lot of HF after 20Kz which may or may not be dealt with in your playback machine. Just because it is shown in the mfr data sheet is no quarantine it was done that way. And, I know some do have that extra post-DAC filter. I assume it isnt desireable to have HF because of potential to increase distortion further down the chain. Filter it.... like the CD32 does. I had to add one.
What you see are real measured data from analog output of that process on that machine (ML-9600). Before and after.
When you add the analog output filter, you get a cleaner representation of the original input (back at the ADC input) and also no HF hash. That is all.
I do not understand the direction others want to take this. If your machine has clean (no HF) in output, good for you.
Like I said and tested..... even Blue-Ray/3D DVD/CD player's analog out also has a lot of HF on its analog output.
So, I am not so sure the filtering is universally used by any means.
-------------------------------------------------------
[FWIW --- the filter I made included the knowledge of the input Z of the BenchMark and was designed with the aid of the network analyzer] And, just running the SQ wave thru the ADC and DAC of BenchMark mfr shows no HF and no artifacts at the analog output. And no file storage, Redbook spec, CD burner involved. Still at USD $4000 msrp. These would be what I would use in critical situations along with perhaps the i7 computer and burner. The good sh*t.
THx-RNMarsh
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What I did plays just fine on any CD player. I just played it on my top end SMART Samsung 3D A-V player for my video system. The mastering machine burns a CD in Redbook form.
[You can find out why/how by reading the manual on the unit via web site download.]
But I think you guys are getting bogged down in the technology issues.
Recall, I had made a pure 1KHz Redbook CD and playing it back to measure the THD and the THD+N. I want to know what the complete record/burn/play system produces in distortion. I found the the THD + Noise was really high when I measured at 80KHz BW. I thought it was defective machine because the noise was way too high. So I threw the network analyzer/spectrum analyzer on it and find all this HF stuff there.... far beyond 80KHz, too. That got me to remove it with a passive filter.
ETC.
-RNM
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