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Post by yves on Dec 27, 2016 17:33:15 GMT -5
Remember the fact almost all (with only few exceptions) modern DACs use internal upsampling regardless of whether the data has already been upsampled before it gets passed on to the DAC. The DAC that I have can support 384 kHz sampling frequency, and, in my not so humble opinion, Alexey Lukin's resampling algorithm (iZotope RX 5 Audio Editor) sounds much better to me than HQPlayer. I do not think that is correct. A DAC does not repeat the up-sampling process below the sample rate fed to it. If you have a DAC that up-samples to 384KHz and it is fed a 192KHz up-sampled signal from HQPlayer the DAC will only up-sample one time from 192 to 384. If the up-sampled signal was already at 384KHz the DAC would not up-sample at all. I use Audirvana which contains iZotope on my iMac. The sound is fantastic, but it does take considerable work to set the filters and such for the best sound. Of course you can use the default settings if you wish. HQPlayer is an amazing program with a great set of very complex filters you can choose from. The two programs definitely sound different, but both are exceptional. If you use Audirvana do you use custom filters and up-sampling? I didn't say that a DAC repeats the upsampling process below the sample rate fed to it. But rather, the already upsampled data fed to it is internally upsampled further still, to 1.536 MHz in the ESS Sabre ES9018 DAC chip (i.e., 384 kHz times four). I don't use Audirvana, but foobar2000 lets me use JScript Panel component so I can use ActiveX objects (and even some COM objects such as AutoItX3, etc.,...) to automate my whole Windows laptop, from within foobar2000 and how I want whenever I want. |
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KeithL
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Post by KeithL on Dec 27, 2016 18:26:56 GMT -5
To be honest with you, I experimented with HQPlayer a few years ago. I found that it did indeed produce slight variations in the sound, some "better", some "worse". However, after the novelty wore off, I didn't find any of them to be a definite improvement over simply playing the source file straight into the DAC. As with anything that modifies the sound, I can definitely see how it could end up complementing the sound of a particular DAC, and so making it sound better - at least to some people..... in some systems. The one thing I would point out, however, is that the reason a DAC oversamples internally is NOT to make it sound better. Without oversampling, if you were to play a CD, at its 44.1 kHz sample rate, in order for it to play "flawlessly", you would have to apply a reconstruction filter to the resulting analog output that was flat to 20 kHz, but was down about 80 dB at 22 kHz or so. If you fail to do this, then you'll get aliasing and distortion. However, designing such a sharp filter is difficult, requires expensive parts, and tends to create other problems - like excessive phase shift and ripples in frequency response. The reason for oversampling is that, by increasing the sample rate, WITHOUT IMPROVING THE SIGNAL ITSELF, you are then able to use a more gentle filter. This gentler filter is easier to design, cheaper to build, and produces fewer unpleasant side effects. Therefore, the oversampling does NOT improve the signal quality; what it does is to minimize the damage caused by the necessary filtering.... with a NET RESULT that the output ends up sounding better. However, this improvement is NOT achieved by improving the signal, but simply by minimizing the damage that the DAC does to it. Once you realize this, the idea of expecting one or another oversampling algorithm to "make more of an improvement" falls into perspective. No current algorithm can improve the signal... all they can do is to minimize damage caused during the conversion process. (And, since the "plain old oversampling" inside the DAC actually does an excellent job, there is a limit to how much that process can be improved upon, if at all.) And, as I mentioned, while some algorithms, like the MQA encoder, claim to actually identify and remove specific types of distortion, those claims remain to be proven... and, as far as I know, no oversampling or upsampling process I am currently aware of actually claims to identify or remove specific forms of distortion in an intelligent and deterministic manner, and so bring the signal closer to the original. They simply apply a specific sort of filtering in the HOPE that you'll think it sounds better than some other alternative type. NOTE: FOR THOSE OF YOU WHO WANT TO PLAY WITH SAMPLE RATES
HQPlayer is cool, but it doesn't let you save files (it only converts "on the fly").
The converter in Izotope RX is excellent (it isn't free, but they do have a 30 day free trial).
Or you could try Voxengo R8Brain (there are both a free version and a pro version).
You can get both here: www.voxengo.com/product/r8brain/
AND, FOR THOSE OF YOU WHO LIKE THIS SORT OF STUFF.......
It's a bit out of date, but here's a performance comparison of a whole lot of sample rate converters...
src.infinitewave.ca/
Thanks Keith for taking the time to answer. I have read that great DACs benefit less or not at all from HQPLayer and the like while DACs some would consider average may benefit more. It does seem almost universally agreed upon that sample rate converters that do not convert on the fly give better results. The AKM DAC in the upcoming RMC-1, may be one of those that would not benefit from up-sampling. Would you agree? |
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Post by yves on Dec 28, 2016 8:10:29 GMT -5
Here's what a 1 kHz tone might look like in the frequency domain after it passes through a DAC.  The purple one on the left is a Sigma Delta DAC. On the right the orange one is a regular DAC, and the dark green/gray one is a regular DAC with noise shaping applied to it. You can see that the Sigma Delta DAC is not only better, but hugely better. So how does it do that? Sigma Delta Modulators are inherently noise shaped. They shift quantization noise out of the lower frequency part of the spectrum. As a result this noise ends up in the higher frequency part. Way up and above the upper frequency limit of human hearing, that is, if the sampling frequency is high enough for that. The farther above the upper frequency limit of human hearing, the more easily the low pass filter of the DAC can remove the noise, as the filter curve rolls off gently above that upper frequency limit. You could instead decide to make this filter roll-off more steep by designing it that way. But doing that would introduce more ringing artifacts in the band below the upper frequency limit of human hearing, where they can become audible. But ringing artifacts are not the only problem to worry about. The filter roll-off still has to be steep enough for it to suppress ALIASING artifacts enough, or else the part of them that's in the band below the upper frequency limit of human hearing can become audible. So the optimum steepness of the filter curve will have to be based around a certain tradeoff between ringing and aliasing. By increasing the sampling frequency in Sigma Delta DAC, not only can you make the filter less steep, but as a very cool bonus the Modulator will shift MORE noise out of the audible band. The reason why it does that is because the total noise power remains the same, but the noise gets distributed over a wider band as the sampling frequency goes up, making it quieter as a result. Shown below is the relationship of SNR (Signal-to-Noise Ratio) vs. Oversampling Rate and Modulator Order (1 - 5) in Sigma Delta Conversion.  |
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Deleted
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Post by Deleted on Dec 30, 2016 17:18:00 GMT -5
Thanks for starting this post wilburthegoose!!!
Some really good post, VERY informative. I was going to experiment with another PC using hqplayer
Thanks to all, good stuff!!!
Thanks again.
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Post by wilburthegoose on Dec 30, 2016 18:45:15 GMT -5
 You're going to hate me, but I just did a "blind" test with my wife. Right now, I don't hear a heck of a lot of difference. But I'm going to try again over the weekend! |
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Post by garbulky on Dec 30, 2016 18:47:15 GMT -5
You're going to hate me, but I just did a "blind" test with my wife. Right now, I don't hear a heck of a lot of difference. But I'm going to try again over the weekend! You have to wear NOTHING but a towel and blindfold! Otherwise the results are invalid. It helps if you also wear ear plugs. |
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Post by copperpipe on Dec 30, 2016 18:52:55 GMT -5
You're going to hate me, but I just did a "blind" test with my wife. Right now, I don't hear a heck of a lot of difference. But I'm going to try again over the weekend! Nope, no hate at all; it's good to see someone admitting they made mistakes or were wrong (I, uh, never get that chance   ) |
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Post by monkumonku on Dec 30, 2016 20:59:25 GMT -5
You're going to hate me, but I just did a "blind" test with my wife. Right now, I don't hear a heck of a lot of difference. But I'm going to try again over the weekend! Do you hear ANY difference at all? Sometimes I think audiophiles think it is shameful or reflects poorly on them when they say they don't hear any difference at all, but I do believe in many cases, there is no truly audible difference. |
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Post by Deleted on Dec 30, 2016 22:38:58 GMT -5
It cannot sound better than what you put in. Yes it can (to your ears, brain and perception) if you subconsciously presumed ahead of time it will sound better. It's been proven a million times. On initial listening many concentrate extra carefully and imagine they hear differences. |
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Post by Deleted on Dec 30, 2016 22:47:23 GMT -5
You're going to hate me, but I just did a "blind" test with my wife. Right now, I don't hear a heck of a lot of difference. But I'm going to try again over the weekend! Kudos to you for at least trying the blind type test. Whether it convinces you that you indeed do or do not hear a difference, you will be more strongly convinced of your decision to keep it or not. Having an open mind is commendable versus those who are completely obstinate and have never even considered other opinions. |
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Deleted
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Post by Deleted on Dec 30, 2016 22:57:20 GMT -5
You're going to hate me, but I just did a "blind" test with my wife. Right now, I don't hear a heck of a lot of difference. But I'm going to try again over the weekend! You have to wear NOTHING but a towel and blindfold! Otherwise the results are invalid. It helps if you also wear ear plugs. So now the Gar has become an expert on blind testing. It doesn't make any difference about a towel, blindfold or ear plugs. This is a very practical test at home. The object is to make sure you have no idea which is playing (regardless of how that is done). I don't think your wife is going to try to deceive you, even unintentionally. When my wife did some switching for me that was perhaps audible, I looked the other way had her make a loud vocal noise so I couldn't hear the switching, nothing complicated here. We did the test more than once for consistency. |
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klinemj
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Post by klinemj on Dec 31, 2016 7:43:16 GMT -5
It doesn't make any difference about a towel, blindfold or ear plugs. It is vital that the listener and his wife are naked. Let's not forget that! However, we tried this at the local audio store once, and the manager at Best Buy got very angry. Mark |
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Post by yves on Dec 31, 2016 7:56:19 GMT -5
You have to wear NOTHING but a towel and blindfold! Otherwise the results are invalid. It helps if you also wear ear plugs. So now the Gar has become an expert on blind testing. It doesn't make any difference about a towel, blindfold or ear plugs. This is a very practical test at home. The object is to make sure you have no idea which is playing (regardless of how that is done). I don't think your wife is going to try to deceive you, even unintentionally. When my wife did some switching for me that was perhaps audible, I looked the other way had her make a loud vocal noise so I couldn't hear the switching, nothing complicated here. We did the test more than once for consistency. So now the Nut has become an expert on blind testing. It doesn't make a difference about very practical at home. The object is you not only have no idea which is playing, but also to make a best effort at eliminating all weaknesses that bias your test results towards either outcome (regardless of what that outcome will be). A loud vocal noise so you couldn't hear the switching already qualifies as a bias towards hearing no difference because it is distracting enough for you to lose your focus whilst trying to listen for differences, nothing complicated here... just your unintentional embarrassing yourself again... just like you did consistently in the other thread. |
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Post by Deleted on Dec 31, 2016 8:03:38 GMT -5
Oh, I'm so embarrassed!
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Post by yves on Dec 31, 2016 8:25:20 GMT -5
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Post by Deleted on Jan 1, 2017 14:10:12 GMT -5
In the words of the Stereophile magazine founder Gordon Holt:
“Audio as a hobby is dying, largely by its own hand. As far as the real world is concerned, high-end audio lost its credibility during the 1980s, when it flatly refused to submit to the kind of basic honesty controls (double-blind testing, for example) that had legitimized every other serious scientific endeavor since Pascal. (This refusal) is a source of endless derisive amusement among rational people and of perpetual embarrassment for me..”
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Post by yves on Jan 1, 2017 15:17:08 GMT -5
In the words of the Stereophile magazine founder Gordon Holt: “Audio as a hobby is dying, largely by its own hand. As far as the real world is concerned, high-end audio lost its credibility during the 1980s, when it flatly refused to submit to the kind of basic honesty controls (double-blind testing, for example) that had legitimized every other serious scientific endeavor since Pascal. (This refusal) is a source of endless derisive amusement among rational people and of perpetual embarrassment for me..” Well, if it's any consolation to you... I did point to a couple of highly rational recommendations in the other thread on what kind of basic honesty controls should be needed before a testing method qualifies as REAL double-blind testing. But a lot of people still flatly refused to submit to that so adios SERIOUS scientific endeavor. |
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Post by wilburthegoose on Jan 1, 2017 16:36:05 GMT -5
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Post by yves on Jan 2, 2017 7:23:56 GMT -5
I think there's a tendency in this hobby  |
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