TOPIC:

Hello,
I saw elsewhere that when you are setting channels levels in Dirac tool before calibration, it is most important that the blue bar indicator reach the -12db target for all channels.

Before calibration with Dirac, I set the main volume in the receiver and the individual trim level to get 75db for all channels sub included. My sonometer is Galaxy CM-140.
I open Dirac, I set the output gain as instructed and rise the input gain so the left channel blue bar reaches -12db in the green zone. I check the others channels : all are bull's eye at -12db but not the sub channel which the blue bar barely touches the green zone.
Is it correct for a good calibration?
If I want to get -12db with the sub channel I must up the volume into the sub by 3 to 6 db ? Is it better to do so?

The nanoAVR-DL user manual seems to suggest "...if any channel is not in the green zone..." that in the green zone suffices.

So , for the sub channel: in the green zone is enough or at -12db precisely?

Logic dictates that it would make most sense to follow the user manual first.

john.reekie wrote:

Logic dictates that it would make most sense to follow the user manual first.

Does NanoAVR-DL adds 10db in the .1 lfe channel (when system configuration is set to 5.1 on the sound system tab of dirac) before to send the signal to the receiver? Or does nano "knows" that the receiver also boosts lfe signal of 10db and sums it with the bass managed lpf signal from all small speakers crossedover at 80hz? If nano "knows" that, it should let the receiver add the 10db boost?

I am confused because the user manual p.26 says:

When the test signal is send , for instance to the left speaker, it begins into the sub and continues into the speaker. So, if I am not mistaken, the receiver is adding its own 10db boost to the 10 db boost of dirac? Or is it pointless because the bass management is after dirac ( on the contrary of DDRC-88A)?

Dirac does not provide a 10db boost. It calibrates (in 5.1 and 7.1 modes) for 10 db higher output level for the LFE channel.

So Dirac does not "take the place" of the receiver; it takes into count the lfe boost to calibrate in consequence, if I may say.

Thank you.

You got it

Even so, it would be best to have the trim levels set reasonably correct in the AVR. If they are not, I think it will "throw out" the bass management. I need to think more about it. It sounds as though you might have the sub trim 10 dB too low, but I'm not sure why that would have happened. What model is your AVR?

john.reekie wrote:

You got it
(...) It sounds as though you might have the sub trim 10 dB too low, but I'm not sure why that would have happened. What model is your AVR?

Hello,
I have Rotel RSX1562. I must say that, for the sub channel, I do not use the trim level of the receiver but adjust the volume of the sub amp to get 75db. BTW, rotel user manual suggests to set sub level at 75 to avoid sound stage image shifting (one sub only of course).

If I rise the volume of the sub amp (SVS PC2000) to get the blue bar indicator spot on -12db in Dirac settings before measurements, and if I check the spl, I got 80db more or less for the sub channel and 75db for the others.

P.S.: There is a lot of "best practice" threads for ddrc-88A or BM but those are quite rare for DL. Maybe this discussion can help others DL owners.

You're overthinking it.

1. Which setting sounds right to you when watching a movie?
2. If you then run a measurement in DLCT (just a single point will do), what do the left and right channels look like? (Please post a screenshot)

john.reekie wrote:

You're overthinking it.

1. Which setting sounds right to you when watching a movie?
2. If you then run a measurement in DLCT (just a single point will do), what do the left and right channels look like? (Please post a screenshot)

1- Sub at 76-77db and all speakers at 75 on the sonometer (doing so, when I calibrate , output settings in Dirac give the blue bar indicator for the sub channel just at the beginning of the green zone which seems ok according to the user manual). For movie, we listen at lower main volume of course, approx 68-70db;
2- I will as soon as I can

RenPa wrote:

2- I will as soon as I can

Cool. Always better to have data =

I'm wondering if you perhaps have a fairly low xover frequency set in your AVR. That might account for the low pink noise reading.

john.reekie wrote:

(...)
I'm wondering if you perhaps have a fairly low xover frequency set in your AVR. That might account for the low pink noise reading.

I began with 80hz now I use 100hz. The transition between sub and left or center channel is quite the same (fairly better for those channels than for the right front) and rew seemed to show a little bit smoother sub-speakers transition for the right channel at 100hz but nothing to write to my mother!
The graph screen shots will be for a 100hz xo.

john.reekie wrote:

RenPa wrote:

2- I will as soon as I can

Cool. Always better to have data =

Here the left and right fronts, large, no eq, no bass management, full sweep
Left channel


Right channel



Now, with Dirac, main volume of the receiver at 75db for left channel, all others set with receiver trim to 75db except for the sub adjusted with its amp volume to get 75db. In output-input levels tab of Dirac tool, blue bar indicator for all channels was at -12db in the green zone but the sub barely touched the green zone.

Left channel



Right channel

Hi, a couple of things. First, it looks to me like your sub is too low in level. I would raise it by quite a few dB (preferably in the sub itself). Second, there's something funny going on just below 100 Hz, it looks like the sub and mains are cancelling. I'd try and sort this out. I assume your AVR is not very flexible with bass management settings but you could try the polarity/phase controls of the sub and the "distance" setting in the AVR.

Hi,
Ok then, I will rise the volume of the amo of the sub to set the blue bar right on -12db next time I will calibrate, (in a couple of days). To hit this target, I already know that I must add 3-4db to the sub.
About cancelling, I must tell that the sub is aside the right speaker and those 2 drivers have quite the same response.
Integration with center and left is good (I have good support on the xover region) But , for the right speakers it is not good.
I tried to tweak distance in the receiver and also tried reverse 0 to 180 degrees into the sub. Rew shows for the integration with the right speaker little inprovement at 100hz xover and 180 degrees but nothing to write to my mother !
About the choice for a xover into the receiver I have a scale of 20 to 250 by 10 db increments.

RenPa wrote:

Ok then, I will rise the volume of the amo of the sub to set the blue bar right on -12db next time I will calibrate, (in a couple of days).

Um, that's actually not the right way to think about it. Where the meter is is essentially irrelevant, what counts is the integration with the mains. That is, if you want to optimize it.

Can you post your subwoofer "before" measurement?