"hacking" SAM to do convolution

[RayMo]

Hi,
I really wish to have a room correction too. I have been imaging, what would be the quickest implementation way for Devialet, and good enough solution for my needs for now, until a room correction is available(?) in Devialet. I think, the Tone Control can be as it is, because of the ability to adjust tone from remote control for differently mixed audio.
I would add one tab into the configurator screen besides Tone Control tab.
There I would like to see a parametric EQ screen, where I can add a rows of EQ settings / channel, (max 32 / channel?),
for example,
Left:
30Hz, +3db, band width value1
45Hz, +2db, band width value2
100Hz, -4db, band width value3
...
Right:
30Hz, +2db, band width value4
52Hz, +4db, band width value5
110Hz, -2db, band width value6
...
Yes, lot of work to write settings into SD, load it in, and test/measure, and configure again. But once done, it is done.

What do you think, pros/cons?

Best Regards, RayMo

[ogs]

@Hifi_swlon yes they were.. my first post here at DC was about convolution: https://devialetchat.com/showthread.php?tid=47
I think convolution is a lost fight. If Devialet really wanted to do this they would plan it for the CI. It may still happen, but I doubt it very much.

[ogs]

@RayMo this is not room correction, but parametric equalising. Can be done without convolution. In Roon I use both convolution and PEQ. Convolution with filters from Audiolense takes care of maybe 99%. PEQ is used to fix a few small things (mostly in the bass region), but I could do fine with just convolution. Many years ago Devialet offered to create amplitude correction, i.e. EQ in DSP, but they no longer do this.

[Rodney Gold]

I have been messing with DSP eq and room correction since the mid 90's ...sigtech, tact , room perfect , dirac, acourate dspeaker brutefir etc.
The amount of user involvement is very high with all these and its very easy to get it wrong and make things sound worse. Dirac , trinnov etc have teams of engineers etc to develop their packages..people that are specialized in this...unlike devialet who cant even get streaming right!!!!...what chance do they have to get DRC right?


Apart from anything else , messing with even PEQ with the stupid card type configuration is a mission..one of the most important things to me with DRC is the ability to hear changes on the fly in real time..almost impossible to do on the devialet..even just changing tone control knee points requires a 2 card shuffle on a dual mono system.
The amount of number crunching is huge with good systems like trinnov , I doubt the devialet would have the ability to do this internally

User support would be a nightmare too ..

Of the 15 or so devialet users I know only *I* use or even desire room correction..I have set up the free trial Dirac..which isnt hard to use for a few folk and have been bombarded with a multitude of questions etc..and they abandoned it.

[petrik]

I have been messing with DSP eq and room correction since the mid 90's ...sigtech, tact , room perfect , dirac, acourate dspeaker brutefir etc.
The amount of user involvement is very high with all these and its very easy to get it wrong and make things sound worse. Dirac , trinnov etc have teams of engineers etc to develop their packages..people that are specialized in this...unlike devialet who cant even get streaming right!!!!...what chance do they have to get DRC right?


Apart from anything else , messing with even PEQ with the stupid card type configuration is a mission..one of the most important things to me with DRC is the ability to hear changes on the fly in real time..almost impossible to do on the devialet..even just changing tone control knee points requires a 2 card shuffle on a dual mono system.
The amount of number crunching is huge with good systems like trinnov , I doubt the devialet would have the ability to do this internally

User support would be a nightmare too ..

Of the 15 or so devialet users I know only *I* use or even desire room correction..I have set up the free trial Dirac..which isnt hard to use for a few folk and have been bombarded with a multitude of questions etc..and they abandoned it.

Maybe Devialet could surprise us and release a solution together with some DRC specialized company like for example Dirac Then they wouldn't need to do it all from a scratch.

[ogs]

I have been messing with DSP eq and room correction since the mid 90's ...sigtech, tact , room perfect , dirac,  acourate dspeaker brutefir etc.
The amount of user involvement is very high with all these and its very easy to get it wrong and make things sound worse. Dirac , trinnov etc have teams of engineers etc to develop their packages..people that are specialized in this...unlike devialet who cant even get streaming right!!!!...what chance do they have to get DRC right?


Apart from anything else , messing with even PEQ with the stupid card type configuration is a mission..one of the most important things to me with DRC is the ability to hear changes on the fly in real time..almost impossible to do on the devialet..even just changing tone control knee points requires a 2 card shuffle on a dual mono system.
The amount of number crunching is huge with good systems like trinnov , I doubt the devialet would have the ability to do this internally

User support would be a nightmare too ..

Of the 15 or so devialet users I know  only *I* use or even desire room correction..I have set up the free trial Dirac..which isnt hard to use for a few folk and have been bombarded with a multitude of questions etc..and they abandoned it.

Maybe Devialet could surprise us and release a solution together with some DRC specialized company like for example Dirac Then they wouldn't need to do it all from a scratch.

Integrated Dirac is one option or just load the Dirac filter as miniDSP does. AFAIK Dirac uses very short filters, around 9k taps. Too little for proper correction in my view..
Another option would be for Devialet to enable a digital "loop". Digital SPDIF out is already there, so a SPDIF input independent of input selection would do the trick. SPDIF may not be ideal for this as there is a limit of 192kHz, but we'd be free to use any device we like in this "effects loop".  Trinnov,  miniDSP and others are already mentioned. I'll add Deqx and even the Mutec MC3 or similar if one only needs re-clocking

[whatmore]

A digital loop was the other thing (as a newbie) I'd hoped was possible.
It is disappointing for a product that is so amazingly flexible that this stuff can't be done

[ogs]

@whatmore I think a digital loop should be possible to do for Devialet. It would only require some programming, hopefully.. We should suggest this to Devialet, maybe they will listen? If someone from Devialet follows this forum they could pick up the idea and present it internally Think of it: all processing is done externally. Measurements and calculations are done externally, no responsibility for Devialet. As long as I/O is SPDIF compliant it should work..

[Rodney Gold]

A loop would be ideal and not too difficult to program and would solve most external box DSP issues for TT or analog input as well as streaming input
Never used a deqx but have been present at a setup .. the problem was that they had to call the guy in NZ or wherever he was and he had to do the online correction and some fiddling there...maybe the dealer didnt know what he was doing but it was cumbersome and I never noticed any drastic improvement.

Im not sure how this would affect things but the devialet introduces some latency .. my trinnov reports a 4.5m distance to my speakers using it with ordinary power amps which is correct ..it reports 6m distance to my speakers using my devialets .. trinnov says its no problem but I wonder if it would make other packages misbehave
I have Trinnov , DIRAC and direct going into my amps and changing sources switches between them, all level matched
direct is not an option , DIRAC is very good but the trinnov is miles ahead ...but the price is a bit eyewatering

[whatmore]

A loop would be ideal and not too difficult to program and would solve most external box DSP issues for TT or analog input as well as streaming input
Never used a deqx but have been present at a setup .. the problem was that they had to call the guy in NZ or wherever he was and he had to do the online correction and some fiddling there...maybe the dealer didnt know what he was doing but it was cumbersome and I never noticed any drastic improvement.

Im not sure how this would affect things but the devialet introduces some latency .. my trinnov reports a 4.5m distance to my speakers using it with ordinary power amps which is correct ..it reports 6m distance to my speakers using my devialets .. trinnov says its no problem but I wonder if it would make other packages misbehave
I have Trinnov , DIRAC and direct going into my amps and changing sources switches between them, all level matched
direct is not an option , DIRAC is very good but the trinnov is miles ahead ...but the price is a bit eyewatering

Hi Rodney, 
As an Aussie myself I feel the need to point out the DEQX is proudly Australian 
I've tried one of their units and found Alan Langford (who was probably the guy dialling in at your setup) to be incredibly helpful. The issue I had with their units is they only use PEQ for room correction. They do speaker correction with convolution but they feel that it can't be done well in-room.
Having tried Dirac and Acourate, I don't agree with them on this point.

I currently use Acourate to generate my filters and have found it to be better than Dirac. I've not tried any of the stand-alone units (I've heard great things about the Trinnov but as you say.... the price ...
 But presumably if Devialet allowed an effects loop you could run the convolution in your Trinnov