SPL calibration for 85db question

[Rylan]

I’m getting back into calibrating my 7.2.4 setup and am going to start learning now to use REW. I have a question regarding something I read about 85 dB movie reference…

“Since 85dB pink noise is way too loud in a small space, the test tone in Av receivers is generally offset by 10dBs so that it is played back at 75B. The speakers are still calibrated to 85dB.”

Would this be true for my Denon x4700H? Should I use my SPL meter with a C weight at 75dB pink noise and expect that it’s calibrating to 85dB? Or should I calibrate it to 85dB myself?

 

[lovinthehd]

Yes, it's setup so it makes up for the difference automatically. So you measure at 75, the avr will adjust for reference levels automatically. It is definitely better than 85dB test tones!

 

[Rylan]

Great! Thank you for the feedback. Will likely have questions to come as I start to learn about calibration using REW. I just downloaded this guide on using REW. https://simplehomecinema.com/2021/02/23/getting-started-with-rew/

Will see how that goes. If anyone has any suggestions for REW video links or literature, that would be helpful

 

[Trell]

Just use the calibration available on the Denon for setting level and distance for each speaker/subwoofer, and is easier than using REW.

With REW you can try out various placements of speakers/subwoofer to find something that works well, and then run the Denon calibration (Audyssey) again. And remeasure. For this you don’t need the correct level, just that you get a nice measurement.

There is also an app for the Denon to make adjustments, and here REW is very useful.

 

[lovinthehd]

Great! Thank you for the feedback. Will likely have questions to come as I start to learn about calibration using REW. I just downloaded this guide on using REW. https://simplehomecinema.com/2021/02/23/getting-started-with-rew/

Will see how that goes. If anyone has any suggestions for REW video links or literature, that would be helpful

Takes a while, the main forum for REW is at AVNirvana and think some of the best info is there (as well as where the creator of REW tends to hang out). Did you get a measurement mic or do you just have an spl meter?

 

[Rylan]

Thank you for the input. Last year I spent a lot of time learning what to apply and getting all my settings accurate. I used the Denon calibration and have everything set up. I do want to learn and go deeper into calibration. I purchased a UMIK-1 last year, but have not had a chance to put it to use yet. Like you said, I may find that sticking with the Denon Audyssey calibration much easier and REW ends up being too complicated and use it simply for calibrating my 2RSL subs. I will see how the REW guide goes and see how complex it is

 

[Rylan]

Takes a while, the main forum for REW is at AVNirvana and think some of the best info is there (as well as where the creator of REW tends to hang out). Did you get a measurement mic or do you just have an spl meter?

Yes, I have the UMIK-1 Mic and a quality SPL meter

 

[lovinthehd]

Yes, I have the UMIK-1 Mic and a quality SPL meter

The software and mic can do spl just fine.

 

[Rylan]

A Few more questions. With my 7.2.4 set up, would you recommend I turn on/off these settings? Not sure if it’s more of a personal preference to use them, or if I can really benefit turning them on and making adjustments to them?

1. Should I enable Dynamic EQ?
2. Should I enable Dynamic Volume?
3. Should I make any adjustments to Reference Level Offset? Or keep it at 0dB?

4. Do you recommend I purchase the Audyssey Multi EQ editor App? and how much more control will it give me?

 

[lovinthehd]

1/ I like Dynamic EQ, particularly at lower volumes where I spend more time these days. Plus, there's the RLO (Reference Level Offset) that it works with. Try this https://ask.audyssey.com/hc/en-us/articles/212347383-Dynamic-EQ-and-Reference-Level

2/ I don't like Dynamic Volume, but in some circumstances some do seem to find it handy, like late night so as to keep things down a bit for the rest of the household. Some like it full time. It is basically dynamic compression.

3/ See 1.

4/ Definitely, quite a bit more control over the eq for customized curves as well as storage of various profiles....

 

[William Lemmerhirt]

A Few more questions. With my 7.2.4 set up, would you recommend I turn on/off these settings? Not sure if it’s more of a personal preference to use them, or if I can really benefit turning them on and making adjustments to them?

1. Should I enable Dynamic EQ?
2. Should I enable Dynamic Volume?
3. Should I make any adjustments to Reference Level Offset? Or keep it at 0dB?

4. Do you recommend I purchase the Audyssey Multi EQ editor App? and how much more control will it give me?

1. Try it and see. I personally don’t like it, but many do. I would try it and try adjustments to #3, RLO. Basically rlo just sets the MV(master volume) reference point where deq starts to kick in. Definitely personal preference thing.
2. Never
4. I have found it useful, and 20 bucks wasn’t outrageous imo. So I vote yes.

 

[Rylan]

I appreciate the feedback!

 

[Wardog555]

Just a FYI on the Dolby guidelines they stated calibration should be 79-82dB

"Each full-range speaker should be calibrated to produce the same C-weighted sound
pressure level (SPL). The target SPL can range from 79 dB to 82 dB SPL(C) at the central
listening position, depending on the room size, when driven with pink noise with an RMS
level of ---20 decibels relative to full scale (dBFS)."

Just thought people would want to know.
75dB works just as well though.

 

[PENG]

The more recent models of Denon, and presumably Marantz as well, is using about 72-73 dB, whereas the older models, such as HD's 4520 (I had the AV8801, same year (more or less) model as the 4520) would be about 74-75 dB, that's based on my Umik-1 and REW, not just the RS spl meter.

With Anthem ARC Genesis, I have to wear earplug every time and hope my smaller surround back/height speakers don't blow, so you can fill in the blank...

 

[William Lemmerhirt]

I think the main thing is channel to channel consistency.

 

[Rylan]

With the few different numbers being suggested, I may need a little clarification. Is it first safe to say that my Denon X4700H will account for the the 10dB lower calibration?

If I calibrate with pink noise at 72dB, can I assume it will adjust to reference at 82dB? Or if I calibrate with Dolby’s guidelines would I then run the pink noise at 79-82dB and I can assume it will adjust to reference increasing it 10dB automatically? Or were you indicating that the finished adjusted calibration should be around 79-82dB?

 

[harleydave]

Lot's of good information in this thread to a newbie like me. Excellent question Rylan. Wondering the same thing myself.

 

[Rylan]

Lot's of good information in this thread to a newbie like me. Excellent question Rylan. Wondering the same thing myself.

@harleydave, welcome to the chat! I spent all of last winter watching hundreds of Audioholics videos and trying to get a grasp on home theater with having zero knowledge to start. I also did some remodeling in my basement to install my set up and create my theater room. I still have a lot to learn, but it has been a really fun journey. This forum, with all of the very knowledgeable experts, have always been willing to help me. It has made a tremendous difference in steering me the right direction. Also, a great guide that has helped answer a lot of my questions (if you are using Audyssey) is found here. It was about $10, but was well worth it in my opinion

Secrets of Audyssey – Guide

Do you want to make Audyssey sound amazing in your home cinema? Well, this is just the guide for you!

simplehomecinema.com

 

[harleydave]

[. Also, a great guide that has helped answer a lot of my questions (if you are using Audyssey) is found here. It was about $10, but was well worth it in my opinion

Secrets of Audyssey – Guide

Do you want to make Audyssey sound amazing in your home cinema? Well, this is just the guide for you!

simplehomecinema.com

I wish my receiver had Audyssey. It's a Yamaha so it has YPAO. I've been reading Audyssey has better correction. I'm fine tuning the best to my ability. I've built acoustic panels, speaker stands, and audio stand. Next up is learning Rew. The people on this forum are awesome!

 

[mtrycrafts]

If you are able to get a good calibration BD with known signal at -30dBFC, that will go through the chain from disc to output. If master volume is increased to 0 with that signal, then you know for sure what the trims needs to be to get 75dB spl. Then you could compare that to the other ways to calibrate, internal test tone of receiver, or the others.