JBL Charge 5 Wi-Fi Sample Rate Conversion

Hi,

I’ve just purchased a Charge 5 WiFi and after setting up and connecting to Roon, very easy by the way, it plays fine, but puts the music through a Sample Rate Conversion, picture attached.

Is it reporting itself to Roon correctly? Is this a limit of the device? Is Roon seeing this device incorrectly?

It sounds good, and this isn’t a reason to return the speaker, as it’s mainly going to live in the bathroom.
I’ll pose this question to JBL support as well.

Thank you

The first conversion up is caused by your volume leveling (and not a problem). The final conversion down is most likely because the device is capable of 48kHz and reported as such (in the same way as e.g. phone devices usually do).

But this is a Charge 5 boombox, nothing more, and it’s entirely irrelevant.

Yep, I should have mentioned the volume leveling, that is on me.

The sample rate conversion I was hoping would maybe picked up by someone in support.
The problem lies with JBL not giving specs on the webpage for this, compaired to other devices they quote sample rate etc. It’s just slightly odd they would Roon Ready a device with this level of capability.

Either way, thank you for your thoughts.

I think it’s nice to have RR in devices of this kind because it makes it easy to have a zone in the bathroom or whatever just like you said, I just wouldn’t get hung up on the SQ effect of 48 kHz output :slight_smile: Best to just have fun with it.

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I’m not worried, as I mentioned in my original post.
But being an ex-IT engineer, this gives me that scratchy feeling something may be wrong in the software, which I know I’d want to fix.

Plus it dawned on me, Roon & JBL are now both Harman companies. They should know how to talk to each other, though I know it’s a new relationship.

Even as it is, it sounds superb for it’s size, though it is mono.

I don’t think it makes any sense to build hi-res capable hardware into this, so it seems entirely normal to me and I wouldn’t think twice.

And yes I have an old Charge 2 with BT and even this one sounds surprisingly good. They are really nice for what they are.

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What input (formats) a given device supports (for convenience of the user) and what internally is being used are two different things. While the former usually gets communicated in datasheets, the later is normally not disclosed to customers. This often leads to false impression of customers about the actual technical capabilities of a given device. AFAIK is Roon Labs proud of its built-in transparency (signal path) and as part of the certification process, manufacturers have to disclose the true capabilities to Roon Labs (and therefore the customer in the end too) at last. Most prominent incident was when Devialet had to admit that their built-in DSP processing limited the signal to 48kHz sampling frequency in their loudspeakers some years back. Up until today I can’t actually recall to have ever come across a single speaker-built-in DSP that was confirmed doing more than 48 kHz at maximum (doesn’t mean it doesn’t exist, just that I don’t know about it). So as the Charge 5 is most-likely a DSP driven loudspeaker (means there is no unprocessed output of input signals), I’m not surprised to see an 48 kHz limitation (in Roon).

Could Roon send higher resolution streams to such a device? Sure if/when it is supported but what good is it when it doesn’t get used? Then there is in Roon’s case the PC that has much more computing power to do a sample rate conversion if necessary that can be used to utilize computation heavier but better algorithms. So as Roon tries its best to deliver the highest quality audio stream to endpoints, that is why you get 48 kHz for devices that can’t process/use higher sampling frequencies. Will Roon Labs comment up-on observed discrepancy between input capabilities as per datasheet of the manufacturer and Roon playback capability? Most-likely not as it is upon the manufacturer to disclose the true capabilities of their devices to their customer. So maybe better ask JBL about this (too).

PS: Looking at the device and it’s price point, I can’t imagine it having built-in DSP capabilities for 96 kHz and/or more sample rate real-time processing.

Thank you for your speculation on the subject.
As I said, I’m just concerned that there may be a software error in the chain, which in this case doesn’t affect the sound quality for me, but may effect other devices with the same or similar hardware which a higher degree is called for.
I understand how all this works, I’ve been around the block a fair few times.

Then talk to JBL. Roon just down-samples when it is needed (the output device doesn’t report a higher sampling frequency) or requested (in this case I think you would know). If you believe there is false reporting by the device, please inform the device manufacturer so he can correct the firmware. There is nothing device specific here on Roon’s side and there is also no ongoing issue with all Roon Ready devices suddenly playing at 48 kHz sampling frequency only.

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You would need to talk to JBL to find out what resolution that device is capable of playing before even assuming there is an issue.

Roon only plays what the device responds as it’s capabilities. So, if the device is responding with a lesser resolution incorrectly, then that would be something to take up with JBL’s programming group.

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I have emailed JBL as I mentioned in my original post.
Waiting on a reply currently.
We’ll have to see if they tell me to talk to Roon.

I’m getting reminders as to why I quit doing IT support. Being bounced from pillar to post.

Again, thank you

Hires is pointless on a portable speaker so why would they add more than it needs. Being Roon Ready doesn’t make a device more capable it’s just a transport mechanism like any other. Devices like this are built with a budget and certain use cases and outside is one of them where trying to resolve high res content is a fools errand given the levels you would need to resolve it. DSP certainly plays a part in getting them to sound as good as they do for their size and shapes and processing this at higher rates it’s again in a small low cost box not really viable. I have several JBL speakers all of which max out at 48/24 over their streaming capability using Google Cast. They claim hires but like many things yes it might accept a hires signal but what it actually does to it is hidden under the hood, until you use Roon which shows you.

It doesn’t always get it right as some mistakes have been made on some products but this is down to the oems interpretation and often gets fixed in firmware later.

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Well I got a non-answer from JBL.

Thank you for your thoughts.

This was never about the quality of the stream, but the potential error in part of the software chain.
As everybody is trying to teach me things I already know, I’ll leave answering here only if a Roon employee decides to chip in.

Hey @Steven_Foster, I’m happy to do that. The Max PCM rate for your Charge-5 WiFi is 48kHz. Roon’s Signal Path is properly reporting its capabilities. No need for worries. :+1:

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