Firmware 13.2.0 - DOS 2.2.6 for Expert Pro - Release note

[Axel]

If Devialet was going to give the Expert Pros room "correction" functionality, then the only way it had to do so was the way it went. Take a look at the M33 as an example of an amp with a software interface and a microphone supplied. Dirac software is actually running in the amp itself and the amp has a microphone input. Devialet doesn't have similar software running and that kind of software does 2 things, it does the measuring and calculation of the correction and it does the application of the correction in DSP. The Expert Pros have DSP capability and can apply a correction, they don't have the software and mic interface to handle the measurement and calculation they may well not have the memory to allow you to load the software for the measurement and calculation process on the amp. Part of the problem why they haven't tried to give us that sort of functionality is almost certainly going to be hardware limitations in the amp. I doubt the current Expert Pro range has the storage available for the software required for measurement and calculation of this sort of correction and I'm not certain that the current OS and firmware would be able to handle mic input from the USB port and providing that capability is going to increase the size of the current OS and FW files. None of us know just what the file storage capability of the Expert Pro range is but it probably isn't significantly greater than what was needed for them to include the functionality they wanted to include when the line was designed.

The bottom line is that if you can't do the measurement and calculation of corrections and you have a DSP engine available, you may be able to modify your firmware so that the DSP engine can apply room correction provided the corrections are created on a separate computer. That's what they've done. It's not the ideal solution but it's probably the only solution they have available with the current hardware. If they can make Sweet Room work, and it seems to have at least one bug with SAM restricting the number of filters that can be applied, then they may consider it worthwhile to ensure that they have the hardware capability in the next amp range to include a full room correction software suite but if they can't get the application of corrections working properly then there's no point in adding full correction capability to a future line. There's no point in releasing an amp that can do the measurements and calculate the required corrections for you if it isn't capable of applying those corrections and they have some problems with that at the moment.

Re @Flashman 's comment about the hard time other manufacturers such as Hegel and NAD are having getting their products certified by Roon, it's quite possible that Devialet is partly to blame for that. Devialet didn't have an easy road to certification either. I seem to remember that it took them longer than they anticipated to reach the point where they could present a product for certification and it then took longer than Devialet hoped for them to get certification. If I remember correctly they submitted their software to Roon in November '18 and announced to owners that they hoped to have certification in a matter of weeks with a FW release in December. We got the FW release in February '19, 2 months later than they had hoped. Devialet didn't have an easy run at it and in the end a bug slipped past both Devialet and Roon and it caused headaches for both companies. I wouldn't be surprised if Roon hasn't implemented a more rigorous certification process at their end in order to try and make it harder for bugs to slip through the certification process and cause similar headaches for Roon in the future, and that kind of rigour also helps the manufacturers to avoid having to deal with bugs and leaving customers in limbo for 20 months as Devialet did with us. Once bitten, twice shy as the saying goes. Roon got bitten with the Expert Pros and probably doesn't want to get bitten again. As for Devialet, it seems to like getting bitten by the bugs in its firmware because it seems to like putting out releases that harbour them on a regular basis.

I'll give Devialet an A for effort for trying to do something about room correction, I'll give them a fail on delivery for releasing something that has problems and doesn't do what it's supposed to do if you're running SAM, and I'll give Roon an A for taking a more cautious line on certification after their experience with Devialet's bug because I think that if other companies are finding it hard to get certification finalised, caution on Roon's part due to Devialt's bug is the reason for longer certification time frames.

If Devialet made it possible to load configurations via Ethernet, do you think it might be possible to then use the redundant SD card for extra memory to enable the storage of the software for DSP? I’m aware that at present there seems to be a problem using SD cards over a certain size, but they may be able to address this with a FW update.
Also, the amps do have two way USB functionality, although the amp has a “B” connector it might be possible to use an adapter like this: https://www.amazon.co.uk/Generic-Type-Fe...B000AA2SMS or this: https://www.lindy.co.uk/cables-adapters-...pler-p6022  to enable microphone connection.