The digital world we live in gives end users unparalleled access to content on demand. But with great power comes great responsibility and Anthony Grimani looks at how integrators can keep quality up amongst the quantity of content.

Some of you may remember the endless Dolby vs. DTS debates from the late 1990s and early 2000s when DVD was king. Then lossless audio came around on Blu-ray and basically killed that. Digital copies and streaming then replaced disc, and Dolby more or less established E-AC-3+JOC (better known as Dolby Digital Plus Atmos) as the de facto standard, because they were the only game in town.

Now, DTS has re-emerged with their new streaming codec, which has made inroads with the IMAX Enhanced format on Sony Pictures Core and Disney+. If you’re hoping to re-kindle the debate… well, then, you’ll be disappointed, because I want to bring Dolby and DTS (as well as other streaming codecs out there) together… in order to congratulate them.

Imagine you have 1L of ice cream to serve to a picnic table full of your friends outside, but all you have to carry it in is a 500mL container. You’re stuffing, cramming, smashing, trying to squeeze in all that creamy goodness so you don’t disappoint your friends, so they all get enough, but it just won’t all fit. Something doesn’t make it. You have to decide what doesn’t.

In the world of digital copies and streaming, providers have to consider the size of the content, the size of the pipeline, the demands of the consumer base at large, and the finances available to deliver a sustainable and satisfactory product. Thus, streaming audio codecs are called upon to greatly reduce the file size, and they do a darn good job. They really do. I mean it. When you consider that 10-16 channels of uncompressed audio with a resolution of 24 bits/48kHz are around 12-17Mbps, the fact that a presentation even remotely similar can be achieved with streaming at around 400-800kbps is just phenomenal. So, great job, everyone.

The fact remains, however, that, like the ice cream, not everything will fit. Streaming audio codecs have to make tough choices about what to leave out. This means prioritising some things above others while striving to maintain a result that is “transparent” to the original or “perceptually lossless”. I’m using quotation marks, here, because these terms get thrown around a lot and mean different things in different circles. Simplistically, it just means that people can’t tell you’ve heavily compressed the audio file and are happy with the way it sounds.

It’s a bit like the great and powerful Wizard of Oz. As long as you’re looking at (or listening to, as the case may be) the whole show, it’s impressive, but you may not want to peek behind the curtain. In terms of streaming audio codecs, the heavy-hitting channels like left, centre and right will be maintained as closely as possible to the original mix.

However, the further you get from them, the cracks may start to show in the compression, especially as the bitrate drops lower and lower. This is especially true if you listen to certain speaker groups in isolation, such as the top channels. Tops are not as important to the overall presentation as the centre, so if a sacrifice must be made, it makes sense to take it out of the tops. As a result, the top channels end up sounding swishy and unnatural.

These compromises are satisfactory for consumers at large with an installed base of sound bars and basic surround sound speaker systems. However, your custom-integrated systems should be striving for the very top level of premium performance. You need source material that does the same. How do you navigate this?

First, realise that some streaming providers typically use higher bitrates for audio than others. It may not seem like 400kbps vs. 800kbps would make a huge difference, but it can be significant on premium sound systems. There are a few enterprising individuals out there who keep track of the bitrates that the various providers use, and you can find the latest documentation fairly easily with a Google search.

Now, we haven’t calculated the numbers ourselves, but based on what is publicly available, Netflix, iTunes/Apple TV+ and Disney+ appear to be toward the top end of streaming bitrates, while Amazon is at the low end. Fandango at Home (formerly VUDU) is somewhere in the middle. This is consistent with what we hear when we listen to the various services. You can find the bitrate numbers for yourself using the Apple TV developer mode. Instructions for how to do this can also be found online. What I would recommend is that you do your own investigation and determine for yourself which services meet your standards and recommend these to your clients.

Second, try to steer your clients away from streaming, period, when content is available in another format that offers a higher bitrate or lossless compression. For high-end systems, a product like Kaleidescape or other niche premium movie services is not out of the question budget-wise. For more moderate systems, 4K Ultra HD Blu-ray remains the most economical way to go.

Physical media is in its sunset phase, and it likely will generate an eye roll from your clients but try to impress upon them that discs are only for “special presentations” of particularly significant content like the handful of blockbuster movies that are released each year. You’re not asking them to trot out the Blu-ray player for everyday TV. Just for the few times a year when they really want to be impressed by their systems.

Another solution is to create your own media server experience similar to Kaleidescape by ripping content to local storage and serving it around the home. The legality of doing this varies by country and region, so be sure to check with the proper authorities before you proceed. I do not in any way promote or endorse piracy of intellectual property or illegal breaking of copy protection. If you can’t legally create a local movie server, just install Blu-ray and/or Kaleidescape.

Ultimately, it would be nice if streaming providers could see their way clear to a general increase in audio bitrate. Faster internet connections support this; however, the demand from the consumer base just isn’t sufficient for the extra bits to be allocated to audio. Current bitrates are satisfactory for most folks.

I would encourage you to raise this issue with as many customers, associates and industry insiders as you can, because the more people who ask for higher bitrates, the more likely we are to get them.