TOPIC:

Hello,

Wanted to know if after I upgrade my nanoAVR HD to Dirac, if I would also have the option to turn it back to and HD in the event I wanted to either sell the unit or if I was unsatisfied with Dirac.

It will be crucial to know before I purchase.


Kind regards,

Bryan

@ Contrabass Bry

It's indeed possible to revert. You just might have to be careful if you perform that firmware upgrade back and forth..
(i.e. potential for messing the licensing on the nanoAVR DL).

DevTeam

OK, thank you. So it would be more a matter of ensuring I disassociate my licence from the DIRAC website before proceeding? That makes sense.

Reason I'm asking is due to all your newly released information regarding the "new" bass-management capabilities in some of your Driac-enabled products via a software upgrade.

Since I am unsure if this will extend to the nanoAVR DL, I want to have the flexibility to keep my options open on the hardware I already own.

By the way, congratulations on the roll-out of your expanded product line at CES! Wishing you continued success!

@ Contrabass Bry

It would be more the step of switching from one firmware to another. No need to disassociate anything.
Unfortunately, we don't have any capability to upgrade the existing nanoAVR in the field to support both bass management + Dirac Live. Not enough processing power on the chipset used. Maybe in the future, we can release a new batch with higher CPU for doing both. It would require a hardware upgrade this being said.

Devteam

Thank you for replying.

That is a shame to hear as I have now discovered the flaw in the methodology utilzed by the nanAVR DL. Since it has no bass management prior to creating the filters, it is applying corrections to the incorrect channels before passing to the AVR.

The example went like this. I started by setting the crossover in the AVR to 100Hz for all channels. Proceeded with Dirac measurement series and created filters for the speaker groups of "Left Right", "Center", Subwoofer", "Sur Left Right" and "Rear Sur Left Right". Loaded the filters into the nanoAVR

I followed up my Dirac session with confirmation measurements with REW to ensure the speaker levels were what were expected and the subwoofer integration was smooth. I noticed a distinct hump between 80-200Hz. I hadn't generated any manner of bass boost via my filters (if anything, I was attempting a completely flat frequency response.) To troubleshoot, I turned off the sub to measure the mains. Each of the Left, Right and Center channels measured flat out to 80Hz and then followed an extremely steep roll off (maybe 8th order). So in order to have achieved this, Dirac had to have been boosting the mains around 8-9dB at around 80Hz to counteract my chosen crossover frequency and slope in the AVR.

This is not good.

Then I reversed the experiment while keeping the same crossover in the AVR, I attempted to sculpt the Dirac target for the mains to the approximation of the expected roll-off slope. This left me with a gaping hole in the frequency response between 80-25Hz. So now it is negating the subwoofer curve I created (flat from 20Hz to 80Hz to a 4th order roll-off) that should have covered that hole mentioned above.

Now my only option would be to purchase an additional nanoAVR HD to cover the bass management PRIOR to the Dirac measurements (which I am not currently prepared to do.) That is why I am trying to keep my options open and inquire into the abilty to revert my unit back to a nanoAVR HD.

I can't knock Dirac's ability to clean up the impulse response and time align all the speakers. It does that splendidly. I just cannot abide by the way it is ignoring the crossover setting in it's measurement schema. While I can understand the want to treat the combined response of the sub+speaker, in my example above, it shows how Dirac could potentially damage customer's speakers if the process unexpectedly boosted frequencies that were beyond the crossover slope they set combined with the capabilites of the speakers.

It would seem a rather simple fix to add a measurement set without the sub (to provide Dirac with the capability and roll-off of the speaker, then a follow-up measure that included the subwoofer, perhaps via a prompt: "Power On subwoofer" or "Power Off subwoofer. It still gets all the data it needs while at the same gathering MORE information about how to maximize the speaker+sub integration.

Likely more a statement that should be made to Dirac than miniDSP, but this is the product I purchased.

Contrabass wrote:

T
I followed up my Dirac session with confirmation measurements with REW to ensure the speaker levels were what were expected and the subwoofer integration was smooth. I noticed a distinct hump between 80-200Hz. I hadn't generated any manner of bass boost via my filters (if anything, I was attempting a completely flat frequency response.) To troubleshoot, I turned off the sub to measure the mains. Each of the Left, Right and Center channels measured flat out to 80Hz and then followed an extremely steep roll off (maybe 8th order). So in order to have achieved this, Dirac had to have been boosting the mains around 8-9dB at around 80Hz to counteract my chosen crossover frequency and slope in the AVR.

No offence but it sounds as though you are doing something wrong. You need to have bass management set up correctly in the AVR prior to running Dirac calibration with the nanoAVR DL. If you have, then the "before" plot should show reasonable integration through the crossover region.

John,

It DID have a reasonable frequency response. I was just attempting to see "behind the curain" of what Dirac was doing to accomplish this, just like I would after an Audyssey calibration. And yes, I have Audyssey disabled during this whole process.

The fact remains that I had all channels set to a 100Hz crossover in the AVR. Ran the Dirac measurement routine. Opened REW to measure a full frequency sweep WITHOUT the sub turned on and saw a flat response down to 80Hz with a steep roll-off after that. To me, that points to Dirac boosting the signal to a degree that negates the crossover setting in the AVR. A THX high pass for the speakers is generally a 2nd order to combine with a sealed main so that the electrical + acoustical roll-off combine into a 4th order. In this case, I SHOULD have been down 3dB by 100Hz and ~9dB by 80Hz, but it was at the same level as the frequencies above (based on my target curve being flat to 2kHz then HF tilt 6dB down at 20kHz. This additional energy in the octaves above and below the crossover created that bit of bloat in the mid-bass that I decied to investigate.

Seems a bit odd for the Dirac filter to "fight" the crossover set in the AVR. Just a bit alarmed at that amount of boost added to a targeted flat frequency response. To further clarify, I used the Auto target as a starting point. It suggested a 6dB rise between 500Hz and 150Hz. This I pulled down so that no part of the target curve was above the OdB level in the graph. Heck, to me it seems like my chosen crossover and levels were so smooth prior to the filtering that Dirac assumed a new crossover/roll-off for the mains. For clarification, I have matched Fusion 15 Sentinels for my LCRs (15" Eminence Deltalite woofer and a very capable compression driver/waveguide) They are quite capable and efficient.

So if this is part of the "magic" of Dirac, I think it is flawed

Contrabass wrote:

Seems a bit odd for the Dirac filter to "fight" the crossover set in the AVR.

Dirac can't "fight" the crossover in the AVR, because it can't even see it. If the mains are boosted as much as you say, it seems like there is some other problem, which I would assume is in your bass management. Can you post the "before" graphs?

Will do. Won't likely be until the weekend.

Thank you for joining this conversation. Hopefully there will be something to be gained by all.



Bryan