Understanding problem - eac3to & audio

[DonAns]

I have an audio source - DTS-HD MA 24 bit - lets call it source.dtshd.
I tried to test some things and did the following steps with eac3to (which used Arcsoft DTS Decoder and Flac/libFlac):

First I converted the file to a 24 bit flac:
eac3to source.dtshd flac24.flac

Then I used the down16 parameter:

eac3to source.dtshd flac16_v1.flac -down16
eac3to flac24.flac flac16_v2.flac -down16

From my understanding the 2 files (flac16_v1.flac , flac16_v2.flac) should be the same.

To be sure I also converted them to wav:
eac3to flac16_v1.flac flac16_v1.wav
eac3to flac16_v2.flac flac16_v2.wav

But the files v1 and v2 are always different. What am I missing?
Shouldn't the 2 wav files identical?

Or will be the -down16 differently handled - depending whether the decoder is Arcsoft or flac?

In http://en.wikibooks.org/wiki/Eac3to/How_to_Use the options are described as

-down16 any audio format any audio format downconvert decoded audio data to 14..23 bit

But from that i conclude that the audio stream will be downconvert only after decoding to 16 bit.

[El Heggunte]

Just my (not-so-)wild guess...

from FLAC to FLAC, the 16-bit conversion is done by eac3to itself;

from DTS-HD to FLAC, the 16-bit conversion is done by the Arcsoft decoder instead;;

And no, that Wiki is not a 100%-reliable source.

[hello_hello]

How different are they? Maybe the direct to 16 bit flac conversion is dithered once, while the other is dithered twice. I don't use eac3to much myself so I'm not sure whether it dithers.

[DonAns]

I did only a binary compare. But it is not only the header which is different - the differences are through the whole stream.

What is the best tool to check the differences of 2 audio files?

[DonAns]

I used now Audacity to compare the files. And they seem to be identical.
So I was mistaken and did not use the right tools to compare the streams.

To compare the files I inverted the track of the first file and mixed it with the same track of the second file.

By doing so it also showed that there were also no differences between the 16 and 24 bit version.