Offline Upsampling

[Jud]

Hi Bill. Many of those are professional software suites, some fairly old. It is also a good idea to know something about what the tests are and their purposes.

[Bill Lord]

Hi Bill. Many of those are professional software suites, some fairly old. It is also a good idea to know something about what the tests are and their purposes.

 

Hey Jud, thanks- The logics I was following, if it's "professional" is has a lower probability of being Audiophile snake oil and must produce results.

 

Most of those tests are going from 96khz to 44Khz, which is the opposite of what we are discussing, still there might be some packages in there worthy of discussion. This way we have alternatives to some of the software already mentioned in this thread.

 

I'm a hobbyist with the thirst for knowledge and this topic is certainly an interesting one. I don't have a good understanding of what is going on and I think I'm after what everyone else here is after; Good sound.

 

Since you are helpful and knowledgeable about this topic, what is your ethic about listening to digital music? Do you upsample offline, if so what software? How much disk storage do you have, what hardware (It's not clear to me in your signature). e.g. "I just bought the latest release of (insert your favorite artist) on CD. I ripped it using (Ripping Software) and saved it to my (very large hard drive set-up). Next, I used (an upsampler software package) and saved the output files to my (very large hard drive set-up). Then I use my MacBook Pro w/SSD, music and Audirvana Plus on RAMdisks -> Mapleshade Clearlink USB Plus -> Semi-customized DAC (for detail see Computer Audiophile - Jud - Blogs ) -> Spectral DMC-12 & DMA-150 -> Vandersteen 3A Signature. "

 

I enjoy others ways of doing things and I am interested in how you do it. Thanks.

[mkrzych]

Hi Krzysztof, please remind me what DAC you have. I think the answer in any case will likely be that you would gain fairly little advantage from sample rate conversion in the PC, online or offline, because you will simply substitute one step in the PC for one in the DAC chip. That is -

 

CD rip, no PC conversion, in the DAC you will get: 44.1 -> 88.2 -> 176.4 -> 352.8; then sigma-delta modulation to MHz rates, then conversion to analog.

 

CD rip, PC conversion 44.1 -> 88.2, in the DAC you will get: 88.2 -> 176.4 -> 352.8; then sigma-delta modulation to MHz rates, then conversion to analog.

 

CD rip, PC conversion 44.1 -> 96, in the DAC you will get: 96 -> 192 -> 384; then sigma-delta modulation to MHz rates, then conversion to analog.

 

Because of so many conversions in the DAC even if you do the first one in the PC, I think you will likely hear little difference. That is of course speculation on my part, so if you do the conversion and hear something better out of it, great.

 

My DAC is WM8523 chipset. Do you still think that I cannot benefit too much in the offline upsampling - just in your opinion of course.

[One and a half]

Using the trial version of ConverteR 48x44 and the first file I tried to convert failed.

 

Added one only 96/24 FLAC with dither on, job was to convert to 44.1/16 wav. Ended up with white noise that nicely faded in as a bonus. Checked with Sound Forge and there's no waveform, it's all a solid colour.

 

Not a good start...

 

Am trying to save myself a lot of work by using ConverteR 48x44, since with Sound Forge, there are a few steps involved with Izotope and saving files. The end result is very good though, on commercial Warner recordings, there's little high frequency content anyway that won't be lost converting to Redbook.

[audiventory]

Using the trial version of ConverteR 48x44 and the first file I tried to convert failed.

 

Added one only 96/24 FLAC with dither on, job was to convert to 44.1/16 wav. Ended up with white noise that nicely faded in as a bonus. Checked with Sound Forge and there's no waveform, it's all a solid colour.

 

Not a good start…

 

Am trying to save myself a lot of work by using ConverteR 48x44, since with Sound Forge, there are a few steps involved with Izotope and saving files. The end result is very good though, on commercial Warner recordings, there's little high frequency content anyway that won't be lost converting to Redbook.

 

 

Hi One and a half,

 

Thank you for feedback. It’s very important for me.

 

I can’t reproduce this bug with noise.

 

I suppose main reason of noise possibly in:

1. in the FLAC's metadata,

2. new decoding library,

3. audio data packed in FLAC format (as example DTS, it able produce noise without additional decoding).

 

Periodically appears files that cause different troubles (more often AIFF, WAV, FLAC,...).

 

Usually it simple found and fix, if you can send me this file for checking.

 

Even if file is non-standard (like was solved in last updates 4.1.2 and 4.1.3) I try pass by its mismatch.

 

 

1. What version AuI ConverteR you use?

 

2. As I understand your output settings in main window WAV / 16 bit / 44100 Hz / Dither ON ?

 

3. Send me the file (dropbox, e-mail, any other), please. Contact AuI ConverteR 48x44 - Hi-End audio converter high resolution files

 

P.S. Friends, if you find files causing bugs, if possibly, send me it, please. I try fix such troubles independently free or commercial edition.

 

Best regards,

Yuri

[audiventory]

The logics I was following, if it's "professional" is has a lower probability of being Audiophile snake oil and must produce results.

 

Most of those tests are going from 96khz to 44Khz, which is the opposite of what we are discussing, still there might be some packages in there worthy of discussion. This way we have alternatives to some of the software already mentioned in this thread.

 

Hi Bill,

 

 

SRC comparision site is very useful resource. Yes, there are only 96 to 44 conversion. But it allow approximately estimate and understand: what is quality of sample rate conversion? Even if demo is not available.

 

For full estimating of quality of audio converter need consider not only sample rate conversion, but bit-depth conversion too.

 

Here rise quality dithering matter.

 

For different combinations of sample rates possible different measured features.

 

At SRC Comparision test sweep file has -6 dB level (if I don't mistaken). I do internal tests of AuI ConverteR only with 0 dB sweep. It allow estimate work in highest amplitudes (detect possible distortions).

 

After it pass checking special selected musical signal. It also can cause overload (when 0 dB sweep passed even). As I wrote before AuI has individually tuned filters for each sample rate combination. Such testings pass during creating new fillters.

 

 

 

 

After sound quality also important how conversion software solve full workflow chain in management of home audio library.

 

It must performed with minimal user's action.

 

 

 

Best regards,

Yuri

[dean70]

It is interesting with the SRC Comparisons. r8brain free measures better than r8brain pro, but from what I have read, most prefer the results from r8brain pro.

[dean70]

Why does AuI ConverteR 48x44 Free v4.1.1 brickwall filter at 20KHz when upsampling 192k sample rate to 384k?

[copy_of_a]

Why does AuI ConverteR 48x44 Free v4.1.1 brickwall filter at 20KHz when upsampling 192k sample rate to 384k?

I am asking the same question... (not only limited to 192k to 384K).

[audiventory]

Why does AuI ConverteR 48x44 Free v4.1.1 brickwall filter at 20KHz when upsampling 192k sample rate to 384k?

 

I am asking the same question... (not only limited to 192k to 384K).

 

Hi Dean70,

 

Hi Copy_of_a,

 

Yes. Right. This is done in order to:

 

1. Limiting of frequency range here facilitate work of DAC’s analog filter.

 

DAC’s output analog filter must provide pass audio signal in audible range and suppress rest frequency range.

High sample rates allow do it without using steep analog filter (very expensive and technically hard device).

 

Inside DAC «on fly» oversampling filter does same thing as part of work of analog filter.

Quality of resampling define the finish analog quality.

 

Here we do offline resampling (with complex accurate algorithm) almost without time limitation.

Now we more independent by quality of DAC’s resampling.

It is «half work of DAC».

 

 

2. For some high resolution files we have noise during playback. AuI ConverteR fix it by such way.

 

I don’t sure, but suppose these files created from DSD masters without proper filtration. May by other way.

Some systems due non-linear distortion and wide frequency range shift the noise to audible range.

As result we listen significant noise during playback.

 

Then we convert such file with AuI ConverteR 48x44 (even without resampling) we get pure sound.

Here video about it

 

 

 

Best regards,

Yuri

[One and a half]

Hi One and a half,

 

Thank you for feedback. It’s very important for me.

 

I can’t reproduce this bug with noise.

 

I suppose main reason of noise possibly in:

1. in the FLAC's metadata,

2. new decoding library,

3. audio data packed in FLAC format (as example DTS, it able produce noise without additional decoding).

 

Best regards,

Yuri

 

Posted bad files to Yuri and is working on, thank you!

[dean70]

I did an AB comparison between on-the-fly up-sampling and 2 offline up-samplers (r8brain free and Audacity (best)) without knowing which of the 2 offline test tracks were up-sampled with.

 

Turns out r8brain free up-sample gave a distinct improvement in subjective quality from the other two.

[audiventory]

Posted bad files to Yuri and is working on, thank you!

 

Hi One and a half,

 

Yes. It was bug of FREE edition only. The bug fixed in version 4.1.4.

 

Version 4.1.4 FREE available online here AuI ConverteR 48x44 - Hi-End audio converter high resolution files

 

Commercial editions will updated later. Now adds new functionality. I will write about it.

[audiventory]

New high resolution audio converter AuI ConverteR 48x44 v. 4.1.5. Supported reading and writing WMA metadata and export album artworks from source file folder.

 

More info New AuI ConverteR 48x44 v.4.1.5. Support WMA metadata | Audiophile Inventory

[One and a half]

Hi One and a half,

 

Yes. It was bug of FREE edition only. The bug fixed in version 4.1.4.

 

Version 4.1.4 FREE available online here AuI ConverteR 48x44 - Hi-End audio converter high resolution files

 

Commercial editions will updated later. Now adds new functionality. I will write about it.

 

All working again, bought the Produce-RD version for conversion from PCM to DSF. What I hear so far is very, very good indeed. More reports later in the week.

 

For gapless PCM albums it would be prudent to stitch the files together in PCM and convert in one large file, marking the track numbers according to the original time stamps, which is reasonably easy to do even with basic sound editors.

 

Is there a file size limitation of what the DSF file can be created when converting? I imagine it's less than 4.3GB(?) to comply with DVD sizes.

[audiventory]

All working again, bought the Produce-RD version for conversion from PCM to DSF. What I hear so far is very, very good indeed. More reports later in the week.

 

For gapless PCM albums it would be prudent to stitch the files together in PCM and convert in one large file, marking the track numbers according to the original time stamps, which is reasonably easy to do even with basic sound editors.

 

Is there a file size limitation of what the DSF file can be created when converting? I imagine it's less than 4.3GB(?) to comply with DVD sizes.

 

Hi One and a half,

 

Thank you for kind words and feedback on CA.

 

Currently for smoothing DC shift (present in some DSD files) AuI do processing that cause some little gap on some track's borders. In case than track border has significant level. I had talk about it with one AuI's user.

 

In current 4.1.6 beta I did turn on/off DC smooth capability. And it planned for upload today or yesturday.

 

Also I have idea (need check it) of special seamless mode for albums. It must work in series without multy CPU ability.

 

Before converting files must be sorted (auto or manually).

 

 

Best regards,

Yuri

[copy_of_a]

Dear Yuri,

 

in another thread the question of gapless SRC with multiple tracks of an album came up.

Never used AuI for resampling an album with gapless tracks before … but now found that AuI produces gaps at the beginning and at the end of each track (see attachment comparing the very same tracks resampled from 96kHz to 44.1kHz with Wavelab’s Crystal Resampler, iZotope SRC and AuI Converter, all in linear phase mode).

If you look closely at the peaks and the alignment of the waveforms you’ll also see that AuI does not only produce gaps … it also cuts off a few milliseconds at the beginning and at the end of each file.

While not that much important when resampling Pop/Rock albums (or any album containing individual unassociated tracks) this is certainly an issue and a serious limitation of the software. It would be great if you could fix this.

 

Many thanks!

 

[rodrigaj]

Copy_of_a:

 

I have seen references to iZotope SRC but I can't seem to find information on it on their website. Is this part of a larger package that is sold by iZotope? If so, would you point me to it?

[Jud]

copy_of_a:

 

I have seen references to izotope src but i can't seem to find information on it on their website. Is this part of a larger package that is sold by izotope? If so, would you point me to it?

 

rx4.

 

Edit: I keep trying to make those letters upper case and the "helpful" auto spell check keeps changing them back when I save the edit.

[audiventory]

Dear Copy_of_a,

 

New version with True Gapless Mode ready. Wait news tomorrow

 

This mode, in contrast usual separate file conversion, allow fully avoid ringing artefacts between songs.

 

Parallel processing (multiCPU) don't used for this mode due need serial processing "file-by-file".

 

Best regards,

Yuri

[copy_of_a]

Copy_of_a:

 

I have seen references to iZotope SRC but I can't seem to find information on it on their website. Is this part of a larger package that is sold by iZotope? If so, would you point me to it?

"SRC" ("Sample Rate Conversion") is part of the "RX4" package. There's an adavanced and a standard version (I use the latter). RX4 also runs in standalone mode. To be more precise: some of the features are only available in the standalone version of RX4 (SRC amongst those). Though there's also a "conncet" plugin to roundtrip from your favorite DAW to the RX4 standalone software.

https://www.izotope.com/en/products/audio-repair/rx

 

iZotope SRC is also availabe in many other audio softwares as a builtin plugin ... but I don't have a list of the respective softwares.

 

edit: "Jud" was ahead of me :-)

[copy_of_a]

New version with True Gapless Mode ready. Wait news tomorrow

Dear Yuri - cool, very good news :-)

 

Parallel processing (multiCPU) don't used for this mode due need serial processing "file-by-file".

this might be a good idea, too. On my machine (2009 MacPro 8x2.26GHz Nehalem & 24GB RAM) AuI behaves really strange. When batch converting multiple files either AuI crashes or it causes other applications simultaneously running to crash.

AuI utilzes 100% of all cores (which is good!) but it doesn't play well together with other softewares also utilizing mulitcore processing. Normally softwares utilizing heavy mulitcore usage should balance each other (at least that's how my other softwares behave ... they "share" the multicores; they do not block all the cores for their own processing).

[rodrigaj]

"SRC" ("Sample Rate Conversion") is part of the "RX4" package. There's an adavanced and a standard version (I use the latter). RX4 also runs in standalone mode. To be more precise: some of the features are only available in the standalone version of RX4 (SRC amongst those). Though there's also a "conncet" plugin to roundtrip from your favorite DAW to the RX4 standalone software.

https://www.izotope.com/en/products/audio-repair/rx

 

 

iZotope SRC is also availabe in many other audio softwares as a builtin plugin ... but I don't have a list of the respective softwares.

 

edit: "Jud" was ahead of me :-)

 

Thanks!

[rodrigaj]

Dear Copy_of_a,

 

New version with True Gapless Mode ready. Wait news tomorrow

 

This mode, in contrast usual separate file conversion, allow fully avoid ringing artefacts between songs.

 

Parallel processing (multiCPU) don't used for this mode due need serial processing "file-by-file".

 

Best regards,

Yuri

 

Am I missing something? I thought you could always limit the number of processors (i.e., 1, 2, 3 or 4)

[Jud]

 

On my machine (2009 MacPro 8x2.26GHz Nehalem & 24GB RAM) AuI behaves really strange. When batch converting multiple files either AuI crashes or it causes other applications simultaneously running to crash.

 

AuI utilzes 100% of all cores (which is good!) but it doesn't play well together with other softewares also utilizing mulitcore processing. Normally softwares utilizing heavy mulitcore usage should balance each other (at least that's how my other softwares behave ... they "share" the multicores; they do not block all the cores for their own processing).

 

Very strange - have noticed no problems on my mid-2009 MacBook Pro (2.53GHz Core 2 Duo, 8GB RAM).