Inakustik Referenz Digital 2404 AIR AES/EBU Review

[Parabellum]

Hey there,

I received today (yet) another AES/EBU cable to insert between my Bryston BDP-3 (to arrive shortly) and my Bryston BDA-3. Right now I am using a Shunyata Alpha AES/EBU (v1) with very good results. When I first got the Alpha, I felt there was too much added loudness but after another cable change on the BDP-2 everything came all togheter and sounded splendid. Thing is, in the meantime I purchased an Inakustik Referenz Digital 2404 AIR AES/EBU but now it is not really needed since I find my system to my taste. Still, I have it so I told myself why not evaluate it and share my findings. For now, I can just content myself looking at it because I have no BDP-3 to play music with. In a matter of days things should be all sorted out.

First impressions? This things screams quality. Inakustik is a German company and until recently never really heard of. They have been in business since 1977 and are a big player in Europe. They are not very well known on this side on the pond. I am leaving some picutures for you to judge but suffice to say, although beefy, this cable is quite light weight. That is because the 2404 AIR series is comprised of 8 individual wires wound in an helix pattern, in a kind of holder that keeps all wires at an equal distance. From their design, they found that air is the best insultator so the moniker. You can check their website and other professional reviews for more information. I will on my side focus on my own findings with the gear I have on hand.

Stay tuned..

[PHC1]

Have fun Serge. Keep in mind that AES/EBU standard was invented the Audio Engineering Society (AES) and the European Broadcasting Union to have the least amount of signal degradation, therefore virtually no effect on sound quality as long as they are true 110 ohm, quality construction. They were not invented for audiophiles but the recording industry for maximum signal fidelity.

The cables are carrying ones and zeros or high and low signal with a clock signal, not an AC music signal.

This will put your audiophile ears to the test for sure. Have fun.

[John Jordan]

Serge (Parabellum)-

Looking forward to your impressions.

Serge (PHC1)-

Thanks for your insight on AES. It's always nice to learn something new.

[audio bill]

Originally Posted by PHC1

Have fun Serge. Keep in mind that AES/EBU standard was invented the Audio Engineering Society (AES) and the European Broadcasting Union to have the least amount of signal degradation, therefore virtually no effect on sound quality as long as they are true 110 ohm, quality construction. They were not invented for audiophiles but the recording industry for maximum signal fidelity.

The cables are carrying ones and zeros or high and low signal with a clock signal, not an AC music signal.

This will put your audiophile ears to the test for sure. Have fun.

I don't want to start a cable war, but have to disagree with the statement "therefore virtually no effect on sound quality as long as they are true 110 ohm, quality construction." Even though an AES/EBU digital cable is used to transmit a "digital signal", the signal is actually transmitted as an analog representation of that digital signal. As such it is subject to degradation, in particular jitter related distortion of the digital data being transmitted and the timing of their state transitions. So depending upon the quality of the sending and receiving circuitry and clocking there can clearly be significant differences in the sound of such "digital" cables. Don't discount what you hear when it comes to any differences noted, human hearing is quite discerning! I have heard some very favorable reports on Inakustik Referenz Digital cables.

[PHC1]

Originally Posted by audio bill

I don't want to start a cable war, but have to disagree with the statement "therefore virtually no effect on sound quality as long as they are true 110 ohm, quality construction." Even though an AES/EBU digital cable is used to transmit a "digital signal", the signal is actually transmitted as an analog representation of that digital signal. As such it is subject to degradation, in particular jitter related distortion of the digital data being transmitted and the timing of their state transitions. So depending upon the quality of the sending and receiving circuitry and clocking there can clearly be significant differences in the sound of such "digital" cables. Don't discount what you hear when it comes to any differences noted, human hearing is quite discerning! I have heard some very favorable reports on Inakustik Referenz Digital cables.

Bill, I presented the post with basic understanding of what the standard is and by whom it was designed. No interface is 100% perfect. AES/EBU is not perfect either but it is what it is. It is good enough for professional engineers in the sound production that we consume on our end.

If there was a clear cut solution, the AES would be perhaps busy implementing it.

I am not interested in marketing hype from any cable manufacture. Please present any articles opposing what I presented or stated from professional/industrial/scientific community so we can discuss it further.

Hype from the audio manufacturers is not evidence. The Federal Trade Commission is too busy frying other fish than to worry about claims how an expensive audio grade outlet by comparison to a medical grade outlet will make your gear sound better or make the medical equipment more accurate... Thanks and looking forward to further discussions.

As to how digital cables sound, let's just say I've compared at least a dozen myself over the years. OK? I am not naïve in the subject. If you hear significant/meaningful difference, great, you made a wise purchase and enjoy it.

[audio bill]

Originally Posted by PHC1

Bill, I presented the post with basic understanding of what the standard is and by whom it was designed. No interface is 100% perfect. AES/EBU is not perfect either but it is what it is. It is good enough for professional engineers in the sound production that we consume on our end.

If there was a clear cut solution, the AES would be perhaps busy implementing it.

I am not interested in marketing hype from any cable manufacture. Please present any articles opposing what I presented or stated from professional/industrial/scientific community so we can discuss it further.

Hype from the audio manufacturers is not evidence. The Federal Trade Commission is too busy frying other fish than to worry about claims how an expensive audio grade outlet by comparison to a medical grade outlet will make your gear sound better or make the medical equipment more accurate... Thanks and looking forward to further discussions.

As to how digital cables sound, let's just say I've compared at least a dozen myself over the years. OK? I am not naïve in the subject. If you hear significant/meaningful difference, great, you made a wise purchase and enjoy it.

I appreciate your acknowledgement that the AES/EBU standard is less than perfect and "is what it is". That's really all I wanted to point out in my post, that SPDIF via coax or AES/EBU cables is not as simple as being a perfect transmission of ones and zeros with no possibility of corruption. While errors corrupting the intended data are indeed quite rare, the timing of the data and clock recovery can be affected in such transmission and ultimately impact the converted audio signal.

I'm not really interested in engaging in a discussion and debate about the possibilities, but can provide you with some articles discussing the technical standard and some of the related problems which can occur in digital data transmission. I hope you find them of some relevance and of sufficient technical merit for your consideration. Many of the 'professional' publications don't get into the sonic implications of the distortions involved since that involves subjective evaluation which they tend to avoid. It's a slippery slope!

https://www.soundonsound.com/techniq...al-interfacing
https://benchmarkmedia.com/blogs/app...nd-its-effects
http://3beez.com/comparison/sound_quality.html
http://www.jitter.de/pdfextern/towards.pdf

[PHC1]

Bill, excellent. We all know that nothing is quite perfect. It gets us close enough though where we can go on with our lives enjoying the less than perfect things surrounding us... I will gladly take a look at the article this evening.

As far as digital cables go, there is not much to address other than the fact that typically a well designed and quality constructed cable. Even those cables costing less than 4 digits in price, as would be used by those guys involved with our music in the first place, will carry the signal and the clock.

The main source of the problem is the even slightest impedance mismatch causes reflections of the signal from the receiving end back to the source. The reflections are typically not large enough in amplitude where it causes a misread of a 1 rather than a 0. So no sweat there. Since the construction of the cable can not alter the signal itself, there is no audible difference in tone/timber. Right?

However, the reflected signal can and does mess up the leading and trailing edge of the timing/clock... That is somewhat of a problem as it introduced jitter. Yes, we know that.

However, what I personally do not like, is exploiting the weakness for gains. You know what I am talking about here.... Jitter. How audible is it really?

Well, here is an overly dramatized example you can hear for yourself. This is magnitudes more than is typically measured in D/A converters and interfaces.

Now, it really does not matter to me if one hears a difference or not with digital cables. It is not up to me to listen to your system with your ears.

Technically it should not happen and I have never heard a significant enough difference but if you do... well, anything is possible I guess. Jitter they say is audible.

Test that theory for yourself here. http://www.sereneaudio.com/blog/what...ter-sound-like

[Parabellum]

Finally, it's here!! I was waiting for my Bryston BDP-3 to arrive before I could evaluate the Inakustik. So tonight I reinstalled the SSD onboard and configured the BDP-3. It took about 1.5 hours to be back up and running as I was before with my BDP-2. So for now I installed the Shunyata Alpha AES/EBU to familiarize myself with the BDP-3 and will leave it for a few days before I swap the cable. Stay tuned!

[Parabellum]

Okay, so I have decided tonight to plug the Inakustik between the BDP-3 and BDA-3, in lieu of the Alpha AES/EBU. I spent about 1 hour shuffling thru my usual demo tunes and it was very easy to pick up a winner here. To my tastes and in my system, the Alpha AES/EBU is audibly clearly the better one.

Since I am no profesional reviewer, I believe to give some perspective to those who read is to have a base line for comparison, or some benchmark if you will. This is why I am switching from one cable to the other to highlight more easily the differences.

After I plugged the Inakustik, I could easily hear that this cable has less meat on the bone and sounds less convincing compared to the Alpha. It must be stated that this is an excellent cable to begin with and is priced similarily to the Alpha at 1100$US/1M. But regardless of price, the Alpha makes the music sound more real, closer to the live experience. I noted in some other thread that as soon as I plugged the Alpha, I felt the music to sound big. This hasn't changed. It is even more pronounced when directly compared to a more neutral presentation like one of the Inakustik. I noticed that with the Alpha, the music feels more "there", is more forward in my room. The soundstage is bigger and more expansive as well. To my taste, the Alpha had to be balanced out with another cable combination as it could even sound "too much" if not properly matched. The Inakustik I believe will benefit most from warmer systems and my be a bit lean for neutral to brighter systems. Again, this is a matter of personal taste and careful matching.

The level of details the Alpha is throwing is astonishing. The Inakustik is not far behind but cannot convince as much as the Alpha does. The Inakustik, while very good, does not immerse me in the music as the Alpha does. The front/back soundstage is more convincing with the Alpha. In comparison, the Inakustik sounds a bit less 3D.

Had I had only the Inakustik, I would have been very pleased with it. But the thing when you try something else and compare, you realize you may like something else better to suit your taste.

Well, I could go on and on but I think you get the picture here. To my taste and in my system, I preferred the Alpha for it better bass response, "realness" and expansive soundstage. Whatever Shunyata is doing, it works and one can hear it. In conclusion, I might sell both in the end... Why you ask? Answer: SIGMA!!

[audio bill]

Thanks for sharing your experience with us, Serge. You've confirmed how digital cables can sound very different even when they adhere to the standards. As is typical with most audiophiles we're never satisfied and always seeking a higher level of performance, hence your desire to now pursue the Sigma! I look forward in time to hearing your thoughts on it and the further gains it offers. Enjoy the music on your fine system in the best of health!