Dirac Live 3 “spatializer”

[Abelard]

I have only about 10 hours of listening on Dirac Live 3 enabled audio system. My question: is there a spatial audio algorithm running in a Dirac Live 3? Anyone else feel like the spatial audio enhancement that was a feature on TVs of days gone by is present with Dirac Live 3? There is no mention of it on there website. I recall from 80s or early 90s this was marketed by a computer my called Omnisonix(?) and added to some Sony equalizers.

It just feels like there is more going on than EQ.

 

[TimW]

When I allow Dirac to run full range it does something I don't really like. I have never experienced a "spatializer" but to me it sounds like Dirac is screwing with phase. This makes sense since they claim to be doing impulse response correction using "patented mixed-phase technology." To me it just sounds kind of unnatural compared to the uncorrected response, at least above Schroeder frequency. There are positives and negatives to the correction and I find it to be more useful when using speakers that have frequency response irregularities. However when the speakers have an excellently linear response or you can correct the response using PEQ based on Anechoic measurements, then IMHO Dirac is only beneficial at and below Schroeder.

 

[abdo123]

When I allow Dirac to run full range it does something I don't really like. I have never experienced a "spatializer" but to me it sounds like Dirac is screwing with phase. This makes sense since they claim to be doing impulse response correction using "patented mixed-phase technology." To me it just sounds kind of unnatural compared to the uncorrected response, at least above Schroeder frequency. There are positives and negatives to the correction and I find it to be more useful when using speakers that have frequency response irregularities. However when the speakers have an excellently linear response or you can correct the response using PEQ based on Anechoic measurements, then IMHO Dirac is only beneficial at and below Schroeder.

The phase correction is always there full range, regardless of what you specify during the filter building stage.

So yeah your bias is showing. Or you’re just reacting to a non-flat on-axis response.

 

[TimW]

Well I'll be damned.

 

[Χ Ξ Σ]

Well I'll be damned.
View attachment 191759

View attachment 191760

Are these loopback measurements? Looks your speaker's crossover point is at 2kHz, and Dirac was just correcting the phase difference between midrange and tweeter. When I had speakers that crossed at 2kHz Dirac generated similar filters.

 

[TimW]

Are these loopback measurements? Looks your speaker's crossover point is at 2kHz, and Dirac was just correcting the phase difference between midrange and tweeter. When I had speakers that crossed at 2kHz Dirac generated similar filters.

Yes these are loopback measurements from my miniDSP SHD. The speakers are JBL Studio 530 so crossover should be a little lower but maybe the resulting phase shift happens higher.

 

[ernestcarl]

Well I'll be damned.
View attachment 191759

View attachment 191760

HF correction appears rather "mild" -- maybe unnecessarily "wobbly" in its attempt to "fix" small deviations.

 

[TimW]

HF correction appears rather "mild" -- maybe unnecessarily "wobbly" in its attempt to "fix" small deviations.

The HF response equalization was done manually with filters Maiky generated using Amir's Klippel data.

 

[Abelard]

I did a Dirac calibration and set the curtain to around 1000 Hz and up. This was an experiment to see how things might sound without Dirac killing off my bass response. Aside from that I am left with the impression that the stereo image "expands" wen Dirac is employed, consistent with my initial impressions. Anyone else have make the same observation? If so - what causes this? I made the assumption that the more precise tonal match between speakers might / would result in a superior stereo image - something that I might make use of. But in truth I don't know if a wider stereo image would really be an expected outcome of well-matched speakers.

 

[dasdoing]

phase correction will narrow down the center image (read: correct it). some percieve this as image narrowing, some as widning....depending on how you percieve the stereo ambience in the recording

 

[SIY]

For me and my speakers/room, it significantly improved soundstage (much more perceivable difference between rooms in recordings, whether for better or worse) and made the imaging (already the strong point of my speakers) sharper and more distinct, separating the sounds from the speakers into their own specific locations. The impulse responses in-room were noticeably better, as was (expectedly) in-room frequency response. The data supporting this appeared in my AudioXpress review of the NAD M10.

Indeed, their mixed-filter system does do timing and phase correction.

 

[Abelard]

d

For me and my speakers/room, it significantly improved soundstage (much more perceivable difference between rooms in recordings, whether for better or worse) and made the imaging (already the strong point of my speakers) sharper and more distinct, separating the sounds from the speakers into their own specific locations. The impulse responses in-room were noticeably better, as was (expectedly) in-room frequency response. The data supporting this appeared in my AudioXpress review of the NAD M10.

Indeed, their mixed-filter system does do timing and phase correction.

dasdoing and SIY - thank your for your input - agree with both - especially about instrument separation and locations. I did not find anything (thus far) in Toole about why this occurs. I'll keep looking.

I find the $5 remote control from MiniDSP to be an unexpected pleasure as it allows me to switch Dirac on/off rather easily. Somehow I ended up with very close level matching so comparisons are easy and continuous.

 

[dasdoing]

d

dasdoing and SIY - thank your for your input - agree with both - especially about instrument separation and locations. I did not find anything (thus far) in Toole about why this occurs. I'll keep looking.

I find the $5 remote control from MiniDSP to be an unexpected pleasure as it allows me to switch Dirac on/off rather easily. Somehow I ended up with very close level matching so comparisons are easy and continuous.

without a matching phase your center image will shift from left to right and back during a sweep. this is because any delay on one side will shift a centered signal to the other side. what happens is that on some frequencies the left one is earlier, on others the right one. So the effect is that the center image spreads, instead of sounding like a third phantom speaker in the middle.

 

[ernestcarl]

I have only about 10 hours of listening on Dirac Live 3 enabled audio system. My question: is there a spatial audio algorithm running in a Dirac Live 3? Anyone else feel like the spatial audio enhancement that was a feature on TVs of days gone by is present with Dirac Live 3? There is no mention of it on there website. I recall from 80s or early 90s this was marketed by a computer my called Omnisonix(?) and added to some Sony equalizers.

It just feels like there is more going on than EQ.

When I think of the word “spatializer” or “surround enhancement” DSP it sounds as though one is doing much more than simply fixing the phase tracking between left and right channels. In JRiver, the latter is a mid-side DSP plugin that tries to artificially broaden/widen the soundstage.

 

[Abelard]

When I think of the word “spatializer” or “surround enhancement” DSP it sounds as though one is doing much more than simply fixing the phase tracking between left and right channels. In JRiver, the latter is a mid-side DSP plugin that tries to artificially broaden/widen the soundstage.

earnestcarl, thank you for you input. Truth is - I am a suspicious person - and I wondered if maybe the Dirac folks "snuck in" a little spatializing to enhance their product - but to be "earnest" I have no evidence of that being the case. The noticeable effect of a broadened soundstage is a mystery to me (as a many things) that I am trying to understand so that I might incorporate the concept into my never-ending tinkering.

Professionally, with help of smart people, I've delivered simple spatializers with all IIR filters, delay, mixing etc all from reasonably standard DSP audio flows for small (ish) active speakers. These have tended to have somewhat wonky high end that I personally did not like. I've wondered what might be achievable with FIR filters.

 

[Abelard]

without a matching phase your center image will shift from left to right and back during a sweep. this is because any delay on one side will shift a centered signal to the other side. what happens is that on some frequencies the left one is earlier, on others the right one. So the effect is that the center image spreads, instead of sounding like a third phantom speaker in the middle.

This makes sense dasdoing. And this gets to my interest in DiracLIve - sort of. I purchased MiniDSP DDRC88D so that I could go all digital to the DACs of my choice. A recent audition of a 32 bit DAC (not high end) told me I had to get away from the MiniDSP 10x10 HD - its data conversion / analog circuits are a real shortcoming. The DiracLive 3 addition was not a reason to buy this box - but I have a long standing modification / experiment that I'd like to try knowing that there will be "phase implications" and I kind of hoped that a DiracLive 3 calibration might just come in an clean everything up after the mod is in. But I want to keep all of the EQ to myself.

I suspect that there are computer based tools that can accomplish this Phase Only EQ with FIR. Gravity is pulling me to having a PC at the center of my audio system but I don't know if it will ever capture me in its orbit.

Thanks

 

[Abelard]

The phase correction is always there full range, regardless of what you specify during the filter building stage.

abdo123, is there any documentation on this aspect of DiracLIve 3 that you are aware of? Not doubting, just want to explore a bit more.

 

[dougi]

I have just started using dirac with a MiniDSP Flex digital, taking over from a Lyngdorf DPA-1 with RoomPerfect. Certainly, the noticable change in imaging is strange, for me I intepret as getting wider in the middle. Phase/group delay is better in the lower midrange frequencies going by REW, but impulse is now messier with lots of pre-ringing. I thought that was supposed to get better! Speakers are Lintons so inverted tweeter, so can be seen in the no EQ step response.