# Signal Path --- # Overview When we set out to create Roon, we felt very strongly that users should have access to honest and precise information describing how their software and hardware devices are performing audio playback. We also felt that great audio hardware should be showcased. As such, whenever Roon is playing to a [[Roon Ready|Roon partner programs]] device or a recognizeable [[Roon Tested|Roon partner programs]] device, we include branding, artwork, and product manual links. Our ability to support specific hardware devices is deeply related to whether or not we can lay hands on it during development, QA, and when addressing support incidents. If you don't see your favorite hardware manufacturer in our [[Partners Matrix|Partner Devices Matrix]], please get in touch with them. There are no costs associated with our programs other than the requirement that hardware samples be made available to us. It is very easy for poor system design, or poorly implemented or mis-placed DSP to ruin an otherwise excellent experience, and too often, software, hardware, and operating systems silently modify the audio stream without providing any feedback. While it's impossible for us to identify every processing step that is performed on an audio stream, particularly after we've handed it off to a hardware device, we are committed to transparency and make an effort to paint a clear picture at all times. # How to Find the Signal Path In the footer, at the bottom of the screen, there is a little colored light--it might be yellow, green, or bright purple. Click that thing. It should pop up a little depiction of the path that the audio is taking. If you are playing to a hardware device that Roon recognizes, you will also see some information about that product. <img src='http://roon-kb.s3.amazonaws.com/563a50b3-d733-42e5-82e9-af5b60c5ea96.png'/> # Interpreting Signal Path Roon uses four colors to predict the sound quality ## Lossless Signal Path Examples Lossless signal paths are indicated by a bright purple light, and mean exactly what the name implies: that the stream is going from the file to the device without being modified. Lossless signal paths are pretty boring--there just isn't much to look at if no-one's touching the audio stream. This is one of the more interesting ones possible in Roon, because it identifies *two* separate devices that are involved in the playback chain. <img src='http://roon-kb.s3.amazonaws.com/9b8abc7c-5e4e-44bd-8567-f8e75abcbd20.png'/> ## Enhanced Signal Path Examples Enhanced signal paths are indicated by a bright blue light. This means that Roon is performing some signal processing steps on the audio _because you asked for them_. The most common reason for a blue light is that features like [[Volume Leveling]] or [[DSP Engine]] are in use. This is an example of an "enhanced" signal path, in this case because upsampling is configured in [[DSP Engine]]. <img src='http://roon-kb.s3.amazonaws.com/3088219f-4ac5-417a-a85f-c85116c64789.png'/> ## High Quality Signal Path Examples You can identify a high quality signal path by looking for the green light. ### OS Mixer Output While the Mac software mixer does not do anything *too* gross, it might be performing software-based volume adjustments or sample rate conversion before playing the audio. As such, we can't guarantee that the output quality is lossless, so we label it as "High Quality". <img src='http://roon-kb.s3.amazonaws.com/ab959ce4-a8c7-4861-9de1-d0f02a7de64f.png'/> ### Conversions for Compatibility In this example, 192kHz audio is being converted to 96kHz audio because that is the maximum rate supported by this Meridian device. This is an extremely high-quality conversion, with virtually no audible loss in fidelity, but it wouldn't be right to portray it as "lossless". <img src='http://roon-kb.s3.amazonaws.com/b4607b73-6072-4365-bc1a-c0d03907cb01.png'/> ### DSP Volume Enabling DSP volume inserts processing steps into the playback change that interfere with lossless playback. There's nothing wrong with this: Features like this also bring great value! We are just trying to keep things honest. Also note that in this signal path, the volume adjustment is actually happening *outside* of Roon, inside a [[Roon Ready|Roon partner programs]] device. <img src='http://roon-kb.s3.amazonaws.com/491dfa8e-83a3-4caf-8f03-d3933e119c3c.png'/> ## Low Quality Signal Path Examples This is a low quality signal path--you can tell because of the yellow light. In this case, we've labeled it as low quality because the source material is an AAC file. For the most part, if you see a yellow light, it's because a lossy file was involved. <img src='http://roon-kb.s3.amazonaws.com/3ff08396-55c5-471d-843f-6d952f25b69f.png'/> # Notes on Device Branding We try as hard as possible to identify devices one-by-one in Signal Path, but sometimes it just isn't possible. There are several reasons why your device may not show up here: - If we don't have the device in-house, or we don't know how to recognize it, it won't show up. Encourage your manufacturer to contact us! - Many devices that don't have unique driver strings or USB IDs--often these will be named something like "Manufacturer USB Audio" instead of "Manufacturer Product". - Some devices use generic drivers (for example, Thesycon drivers). These can't be pinned down to a particular manufacturer. - ASIO-based drivers do not provide a facility for device identification.
Page last changed Fri May 05 2017