I’m new to Plex, and really think the video side is very good, but having difficulties with the Music capabilities.
I am using macOS 10.14.6 on a Mac Pro desktop computer.
I have a large collection of high-res audio (mostly 16 and 24 bit ALAC) which I normally play via a macos audio app called Audirvana. The audio quality provided by this app is very good; but for a change I thought I would try the music playing abilities of Plexamp and the Plex app. At least on my system the audio output of either of these apps is very poor by comparison - which makes little sense as the source / computer / speakers are identical, all that has changed is the audio app. The Plex audio output is muffled, lacks stereo staging, and dynamic range. The difference between the two is stark - a bit like between listening to music with basic Apple Earpods (the freebies that used to come with iPhones) and through full-on over the ear headphones.
The scale of the difference makes me think that something somewhere is going wrong with the audio processing by Plex / Plexamp. I’m guessing that these are electron apps, and therefore using some version of the web audio features provided by Chrome and that’s not working well - but perhaps it is doing more.
This is an issue mainly because I’m considering the Tidal link in Plex to get HD Audio streaming - but if the apps themselves cannot play HD audio well there seems little point.
Anyhow - I am wondering a) if there is a way to fix this, and b) if not whether there are any other apps about that are able to talk to Plex Media Server but do have credible audio processing capabilities.
I’m using the latest version of Plexamp (there does not appear to be a way to find out the version number from within the App - but Finder reports it as version 3.3.1). The app is talking to a Plex Media Server (Finder reports version 1.20.4) instance on the same machine (i.e. disk storage is local to the playback machine), Music Quality set to Maximum, Limiter disabled.
Thanks in advance for any thoughts / suggestions about what options I have etc.
Thanks for the speedy reply.
I have disabled all the playback options (including loudness levelling), but makes no appreciable difference to the audio quality produced.
The speakers are connected by direct USB connection (they are Bowers & Wilkins MM-1s if that helps).
The computer has no Bluetooth audio connections, but is connected via Bluetooth to an Apple trackpad.
Oh well. Thanks for suggesting anything at all… appreciated. If it is an Electron thing then I guess I’m stuck with the problem until such times as Plex does the decent thing and writes a native macos app … or fixes the audio somehow, since from what I can see there are no alternative plex audio players for the macos platform.
I’m guessing that on iOS devices the audio quality is not an issue (and/or handled differently because of different hardware) - it would seem daft to offer Tidal subscription and not then have the ability to play back the music in a way that uses the hi resolution audio (though I do note that Plex’s support for Tidal is only partial - no support for MQA tracks).
Thanks for the additional info. Disappointing though - I guess that means Plexamp itself is screwing up the audio output… can’t blame something else
Seriously though, do you have any ideas about how the app can be adjusted to correct the audio problems? There appear to be no meaningful controls over sound quality - so right now there appears to be nothing I can do to get Plexamp to produce the same quality audio output as other apps on the mac?
Yes good point. I was surprised that there appears to be almost no discussion of audio quality when it comes to music playback - there is lots I guess about movies. Maybe the focus for Plex is movies not audio. But this is inconsistent with the link up with Tidal - which only makes sense if you have a player that lets you hear the audio quality of the source used - which is why I thought it might be worth trying to find out what is happening / see if it is a problem on my system.
I can dig through the logs for sure, but sounds like even if I find out what is going on there is no interest here in fixing it. Still if I find out anything I’ll post whatever I find here in case anyone else is considering listening to music through the app.
Can you manually set your interface to a given sample rate and bit depth?
If you do, set it to 96 or 192 kHz and 24 bit.
Then close plexamp and restart it.
Perform another listening test.
I use a rather high-priced interface and I had to do this right from the start, since my interface wouldn’t switch automatically.
But I am using Windows, so that might not be viable on your system.
You just keep telling yourself that and I’m sure everything will work out fine. If plexamp was doing a good job of it, why would I post the question that started the thread? I hope it is something that can be fixed, but honestly I’ve got better things to do than post fake questions about non-existant issues.
[quote=“OttoKerner, post:11, topic:652153, full:true”]
Can you manually set your interface to a given sample rate and bit depth?
If you do, set it to 96 or 192 kHz and 24 bit. [/quote]
The options on a mac are less than on windows perhaps, but you can set some aspects of the output format after a fashion using Audio MIDI setup app.
The MM-1s receive digital audio via USB and decode using an on-board DAC able to operate at 44.1kHz and 48kHz, and receive up to 24 bit audio, but the options to control that DAC directly are limited.
The macos output feed to the MM-1s is set to 48kHz (the max rate the MM-1s can take, some discussion elsewhere about whether this setting determines the upper limit rather than forcing the rate) and reports that it is accepting a 2-ch 16 bit integer output stream.
The audio depth sent to the speakers is being determined by the processing app / source. Plexamp reports the correct bit depth / rate information when playing back tracks.
Repeated back-to-back comparisons of 16bit and 24bit sources coded at variously 44.1kHz and 48kHz demonstrate that Plexamp is sending an audibly inferior output to the speakers than other audio apps (e.g. Audirvana, VLC) on this particular computer.
I guess I’m not going to get to bottom of why its not working - much the easier path is to simply give up on trying to get Plexamp to work for audio playback.
But thanks for your help, appreciate the thoughts.
You’d need to repeat the test level matched and blinded and get the same results to be really sure. Two things spring to mind here, both lay in Audirvana’s camp.
Audirvana uses izotope processing which does give it a more sparkling sound (I would call it is less true to the original myself) and there is also likely a difference in output level, with Audirvana being louder. Louder always sounds better. Turn up Plexamp and enjoy.
Yep, I’m aware. I’m fairly familiar with audio testing, and did multiple tests using a variety of music types and encodings, and attempted to match up volume: but for whatever reason on this setup the difference in audio quality between plex / plexamp and other players (e.g. Audirvana, but also iTunes, Clementine, VLC) is easily noticeable.
My assumption when posting my original entry in this thread was that I was doing something wrong and Plex / Plexamp could be fixed by some unknown adjustment. It has become clear in this thread however that it is easier to just walk away - it seems it is too easy for you and others to simply declare that there is no problem and that I’m either confused or being disingenous to suggest there is. Which is not much of a way to resolve anything.
AFAIK izotope used to be an optional processor (for upsampling it appears), but since v3.5 of Audirvana it is no longer available - with upsampling processing being done using the SoX algorithm (which used to be the other option, but now is the only one). Not sure what that implies for your critique of the Audirvana sound, but clearly blaming izotope processing is not valid in this case.
Audio quality above a certain level tends to be pretty subjective. Here’s the experience I can share: I have Plex running on a Mac Mini hooked up to a Focusrite Scarlett interface set to 44.1/24bit. That in turn is running thru a NAD amplifying two large Nubert speakers. Nothing too fancy, certainly not hi-end but a decent stereo setup. With this, my ears have a hard time noticing any meaningful difference to the corresponding track on CD. (Aka … none.)
My guess is that we’re either talking about “hi-end” phenomena (like influences by cable or power supply) or your previous software in deed is using some kind of enhancement. Again: With matching level, I can hear no difference between my (44.1/16) flacs and their corresponding CD originals.
Agreed, my response wasn’t particularly helpfully worded, apologies. I don’t think there’s any hidden settings you’re not seeing with Plexamp, so I don’t think there is anything you can tweak, I doubt there is with any software really unless it has some DSP or EQ available.
As far as I know, Plexamp does not yet support exclusive mode so there may be an issue with the OS audio mixer that is affecting the sound. I don’t use Plexamp on my main system, only as a mobile solution, but I tired it out to see if there’s much of a difference between it and Roon which is what I use. There did seem to be a slightly lower volume output to Plexamp but no real loss of quality for me.
In my book your stuff is pretty fancy… Thanks for the extra data point - useful to know. I’ve not compared CD direct input to replay from an lossless file, but will give it a go… but I will need to go dig a CD out of storage first!
I don’t think it is context related (power supply / cables) as these are identical in tests - just the playback software that is changing: so I guess it must just be a software related issue, and for whatever reason Audirvana and the others are getting a better response from the resources available than plexamp.
Thanks alot for your thoughts.
The way coreAudio appears to be built you get some control within the audio app (by for example choosing which kind of coreAudio playback service you want to use) and via use of ‘Audio Units’ which allow for the manipulation of audio streams (e.g. by adding filtering, or equalisation effects). The authors of an audio app (e.g. Plexamp, Audirvana) can make choices about what of these services they use, and what they expose of these services to the software user. Audirvana appears to use a mix of coreAudio and custom playback code - and you get the option to make some adjustments to these (for each playback device available separately), and allows the user to mess with Audio Units if they want. Plexamp does not do any of this, so hard to compare.
Yes, but on this system not a discrete one - the speakers I use (B&W MM-1s) are USB connected and so necessarily have their own DAC built in. On my proper audio rig I use / playback via a discrete DAC / amp reading directly from the audio storage. When these desktop speakers eventually die I guess I’ll replace with a discrete dac / amp / speaker setup but for now they are a usefully compact solution (this is a work computer, and finding space around it for DAC, amp and speakers in the space around will be difficult).
Why don’t you post your logs as @elan suggested? If Plexamp is really degrading sound quality upon playback, it would be in everyone’s interest to get it fixed.
Thanks for the extra data point - useful to know. I’ve not compared CD direct input to replay from an lossless file, but will give it a go… but I will need to go dig a CD out of storage first!