F/R True AAC/iTunes+ encoding from montage

It seems that while Wavelab does encode to AAC format, it doesn’t have the exact iTunes+ codec that Sonnox Pro-Codec has, particularly when dealing with higher sample rates.

When I load a 48k, 88.2k, or 96k file into Sonnox Pro-Codec and encode to AAC/iTunes+, it also does the sample rate conversion down to 44.1k. I have no choice in the sample rate, it just puts it at 44.1k. Wavelab is different in that it keeps the sample rate unless you manually change it.

Could Wavelab 9 offer the same iTunes+ encoding like Sonnox Pro-Codec?

The sample rate is sometimes automatically changed because some sample rates are bot compatible with certain bit rates. Especially, if you have 96k files, AAC conversion need a high output bit rate.

What I mean is that somewhere in the official iTunes+ AAC codec, the sample rate is automatically set to 44.1k no matter what the source sample rate is when converting a 96k WAV to AAC, it’s not a sometimes thing.

I’ve read that it may be OSX only to do the official iTunes+ encoding but looking at the Sonnox Pro-Codec plugin could be a clue.

I understand some AAC can be higher sample rate but the official iTunes+ codec associated with the Mastered For iTunes program always produces a 44.1k AAC no matter the source sample rate.

I would like to know if Wavelab 9 could have that exact encoding including the sample rate.

There is no plan to use the Apple iTunes AAC encoder. Cross platform features are favoured and the Fraunhofer codec is the solution for this.

I must express some disagreement and disappointment.

As a commercial mastering facility, we are responsible for delivering masters for iTunes everyday. We have necessarily been using the Apple tool on a mac mini, the cross platform you mention. This is NOT “favoured” over having such a tool built into our primary mastering app: WL8. I was excited when I heard the news about an Encoder Checker in WL8 and the potential for streamlining MFiT creation. This was a strong incentive to upgrade.

After some use we are questioning its suitability. First, it does not provide the metrics salient to confident MFiT master creation. Second, it does not even use the official Apple AAC encoder! So what are we monitoring thru this thing for? iTunes is arguably one of the largest outlets for commercial music distribution. Maybe there are legal or licensing reasons for not addressing this professional need. Many nice things about WL8 but this aspect is not proving to be a meaningful tool for our business. I am open to any illumination.

The free tools that Apple offers are OSX only (not a big surprise) but even the iTunes+ AAC encoder in the Sonnox Fraunhofer Pro-Codec is only in the OSX version, so I’m guessing there is something in the codec itself that only allows it to be truly available on OSX and not Windows.

The Sonnox Fraunhofer Pro-Codec Windows version offers something that they claim is close to the iTunes+ AAC encoder, but it’s not 100% the same.

I’m trying to determine if the iTunes+ AAC encoder in the OSX version of Sonnox Fraunhofer Pro-Codec is something made by Fraunhofer or if Sonnox has licensed it from Apple.

I’m sure they’re just using the afconvert commands built into the operating system. Probably don’t have to license anything, just run the simple commands on page 7 of the MFiT PDF, thereby using the OS built-in Apple codec and Apple SRC for the MFiT conversion within Pro Codec. It’s worth looking at that page on the PDF, under “using Afconvert”. It’s incredibly short and simple.

I really think someone could do this on Windows if they wanted to. QAAC has done it on Windows using the Apple CoreAudioToolbox. I’ve done a lot of testing myself and found that in iTunes on Mac, the “iTunes+” encodes are identical to those done by the official MFiT droplet (including SRC). On Windows the encodes are not bit identical, but the QAAC guys say that’s only because of the Windows compiler. But the files are so close as to be identical, and could never be picked in blind test. The most convincing argument that the codec is available on Windows is the fact that Apple calls the encode exactly the same thing in iTunes for Windows: “iTunes+”. If you convert to “iTunes+” on Mac, and you convert to “iTunes+” on Windows, one would hope that the resulting AAC would be (at least nearly) identical, and for all intents and purposes I believe it is. Certainly infinitely closer than using other AAC encoders and other SRC.


qaac requires to install iTunes software compoments, something Steinberg would not be allowed to do. Moreover, there is not realtime possibilities (hence to Encoder checker).

I don’t understand. QAAC is used by a number of free programs, including Foobar. With realtime possibilities, as far as I can tell. And original components installed with iTunes or Quicktime anyway. Qaac.exe and Apple Application Support would not do it?

From what I know, foobar is only a player, hence does not encode real-time streams into AAC (this is needed for the EncoderChecker of course).
Anyway, IMO, there are more important things to develop in WaveLab than implementing another AAC encoder.

Thanks PG. But honestly I think someone else will. I think you were the first, but the other pro mastering apps are slowly adding audition/preview/analyze/auto-adjust/verify and they’re mostly Windows only. Because unfortunately I think the whole iTunes thing is very important to many mastering studios and the “official” MFiT lack on Windows has been a major request. I don’t think Sonnox really wanted to make the Apple encoding the main selling feature on Mac (especially having been called Sonnox Fraunhofer Pro Codec). It has to have been by popular demand. Someone will do it on Windows, but if not possible in Wavelab, I second the feature request to have it added on the Mac side anyway. (as Sonnox has done, probably grudgingly.)

If this is the case, then would it be correct to assume that it is probably best to deliver 24/44.1 files to iTunes for MFit use?

Unfortunately, IMHO the problem lies squarely in Apple’s warping of the AAC format to make their own proprietary format for MFit which those on a PC cannot precisely reproduce. This is everything the audio industry should not be about. It means that any cross-platform application like Wavelab cannot provide the same codec on both platforms. Note that it is only the MFit fiasco which is creating the problem, not Wavelab. We don’t have this problem with any other audio file format.

Not necessarily. If you send higher than 44.1, it will be sample rate converted with the Apple SRC at Apple. It’s part of the commands in the MFiT droplet routine and at Apple. Sending higher rate is actually what Apple would prefer, (reading in to their PDF), since it gives them a higher rate file for the future. But some people prefer using their own SRC to get it to 44.1 before sending it to Apple. Either way it will be converted to 44.1, either by you with your chosen SRC, or by Apple with their Apple SRC in the iTunes+ MFit routine.

That’s sort of what I was getting at. According to QAAC (and to Apple’s own wording as “iTunes+” within iTunes on Windows), it is the ‘same’ codec. The nitpick apparently is about non-complete null based on stuff that doesn’t matter, and for all intents, purposes, and measurements produces AAC files that are virtually and audibly identical to their Mac counterpart.
sorry, just my opinion.

I originally only mentioned all this incase it was something overlooked or not thought of that could be easily implemented.

It’s not that much extra work to create AAC files for clients using the Sonnox Pro-Codec from the source MFiT WAV files that will be submitted to the distributor/aggregator. If the source WAV files are properly and thoroughly tagged with ID3 metadata from Wavelab, it’s pretty quick to translate that metadata to the encoded AAC files using the Sonnox Pro-Codec, and just add artwork. I was only looking to save a step if possible.

Only recently did I notice that the AAC encoding Wavelab does isn’t the exact iTunes+ AAC.

I have some clients that like to submit 24-bit/96k WAV files for MFiT releases, and then they want me provide exact replica files of what users will get from the iTunes Store for them to proof. Sonnox Pro-Codec can do this, but with Wavelab, the sample rate conversion is not the same.

Not a huge deal to me, just an inquiry.

My only other question is if Wavelab could add ability to tag AAC files as gapless. I notice mp3 files do not support this but AAC files do have a gapless playback field.

Exactly. That’s what I meant. If it’s going to get changed to 44.1 by Apple, many would prefer to do their own SRC before sending the file (Crystal Resampler for example) in order to maintain maximum control over the mastering process. I’ve heard reports that the Apple SRC introduces undesirable artifacts when downsampling 24/96 files.

Could you not convert to 44.1 using Crystal Resampler before creating the file using the iTunes+ preset in Wavelab? AFAIK you can also tag the file with metadata in Wavelab. Would not such a replica file be audibly identical to those you are producing with the Sonnox Pro-Codec?

In other words, can you actually hear an audible difference between the two? (I imagine you must have already compared the results).

But yes, I agree it would be helpful anyway if Wavelab could do the same SRC and encoding as the Sonnox Pro Codec if this is closer to what the Apple tools do. FYI some certified suppliers are sending only 24/44.1 files to iTunes MFit because they don’t trust the Apple SRC downsampling from 24/96.

Whether Crystal Resampler or something else is better is subjective but in general, I prefer to avoid the global master section and use the montage master for my global settings so all the plugins and settings are stored in the montage and not as a separate master section file. That was the thing I disliked most about Wavelab when I started using it. I’m glad that PG developed the montage master section.

Crystal Resampler is only available in the global master section which complicates things.

I hope Wavelab 9 incorporates the iZotope SRC and is available at the montage master level. Then I would consider something like you suggest.