Reference Levels And Test Tone Levels! 

I agree with Joe that it depends dbA vs. dbC. 85dbA is loud and hard to listen to, whereas 85dbC is much more manageable since the subs are inflating that number depending on how aggressive your house curve is. Whenever we talk about SPL we all need to be specific which weighting we are referring to.

Reference level has nothing to do with whether it's home or theatrical. Your AVR's auto-cal will set things so that 0 on the relative scale of the master volume will be the same as theatrical reference, which is 85dB average dialogue, 105dB peaks in the channels, 115dB peaks in the LFE. This is why if you're using external noise tones, the level they are recorded at should be a known factor. If they're recorded at -20dBFS and MV is at 0, the tones should read 85dBC. If they are recorded at -30dBFS, the tones should read 75dBC. The difference comes in our perception of those decibel levels in a large space compared to our smaller home space, and in the home space, 75dBC is much easier to tolerate. Now, if the tones are recorded at -20dBFS but you don't want to calibrate to 85dBC, you simply dial MV back to -10dB instead of 0 and calibrate to 75dBC. In the theater, the stream for the track has data that tells the system what the proper level is, so ideally the theaters never have to touch their levels once calibrated. That isn't always the case though, as they'll monkey with the levels and then the next title that comes in will be too loud or too soft. But there's a big reason why in many ways, this no longer matters so much in the home: In the DVD days, pretty much all content was done for reference level (and a lot of it not pre-compensated for home listening) so you could count on what the mastering level was. You also had data in the bitstream that would tell your AVR the difference in mastering level (see DialNorm) if it was adjusted for purposes of dialogue. This is how systems like Audyssey's DynamicEQ would know how to make their changes to bass and surround levels - the amount below reference that you had the MV. The problem is that content creators started changing the levels wildly for home mixes, and doing a lot of pre-compensation for home mixes wherein they compress the dynamic range a bit and roll off the highs. Blu-rays were mostly done to reference even if pre-EQ'd for the home, but less reliably than DVDs were, and the lossless codecs no longer bothered using anything resembling DialNorm. Streaming is now all over the map, with very little consistency. So whereas before, you could count on 0 being theatrical reference... a Disney title might require you turning MV up to +8 to hit actual reference. A more compressed title made for TV might actually go the other way and be encoded too hot, meaning you'd have to turn the MV down say -5dB to hit reference. So basically, if no one is actually making content per the reference anymore, it makes it way less important that 0 on the MV equals theatrical reference on your system. All that matters is that each channel is calibrated to the same level. This lack of consistency in mastering levels is why features like DynamicEQ that rely on the system knowing that 0 = reference vary so wildly with current content and have fallen out of favor. To add to the mess, the pre-compensation of theatrical mixes for the home space, both on streaming and physical media, means that if you EQ your system to roll off the highs to make that compensation as well (as something like Audyssey's reference curve or the curves used in some other auto-cals), you are essentially double-filtering the high end. But that's a whole other discussion... for another time. 😉

0.00 db for center channel -0.5 db for front speakers Subwoofer -4.0 db No higher (of course 🧐) No lower

I see this is an old video, but I would love it if you guys could have a talk on the difference between "trim" and "channel level". People seem to use them interchangeably or maybe some systems do not have both. When I am measuring SPL, which do you change? P.S. I use MCACC or Dirac, so it does the initial trim levels.

Isn’t it true that if you try to level match after running Audyssey using the receiver test tones that it doesn’t work because the receiver shuts off Audyssey while running the tones …..so you should be using external tones to level match after running calibration?

My experience with Denon and Anthem is Denon (Audyssey) works at 75 db for calibration. Anthem (ARC Genesis) IIRC is 80 or 85 db. This may be why in terms of Reference, I would listen around -15 MV on Denon and -24 MV on Anthem. The point being, get to know your calibration program because it seems each manufacturer is different. Personally, I like the flexibility ARC-g provides over Audyssey XT-32. I have no experience with subsequent iterations of Audyssey nor Dirac. From presentations I have seen, Dirac seems to have the most flexibility of the room correction programs. That said, the industry is at a point where new technology is in place to handle RC much differently. Dirac announced a new method of standing wave cancellation in their new RC system currently available on Storm and to be released to Denon/Marantz in October. Trinnov followed suit with their proprietary method of similar technology. I expect ARC and Audyssey to release their versions in the next year or so.

I let me AVR set the reference level and then I go back thru and level match. What is odd is that after level matching the rear height speakers while listening to Music/Movies is always louder than the front heights.

85db is way too loud for my ears I typically use 75db and to be honest I'm always running it 5db 10db lower for 4K physical media and higher for streaming because of the compression

I hear what Paul is saying. I went from a denon 4300 to a anthem 1140 and it definitely sounds 10 db louder then the denon. With the 1140 I listen at - 25 to 30

I calibrate for dynamics for HomeTheater and two channel audio. I Initially set each speaker to 80db. With a high bit depth surround dvd from Mark Waldrep at AIX Records, not the built in test tone from my prepro. That's way too loud and not accurate. Then i begin with PEQing the system. Once i get all channels eq'd, ill do another channel balance at 80db because eq will mess up your initial balance. The last step is to calibrate the system as a whole for 85db total output with 105db bass peaks WITH WELL KNOWN ACTION MOVIES USED AS REFERENCE QUALITY ONLY, NO TEST TONES. Notate where the master volume is on my PrePro. Theres my reference. With my Outlaw 976, its a -15db. My normal listening level depending on the movie is between -20-25 at 9 feet away from the main channels in a medium sized living room. Ive been doing it this way for 20 years and it works great and you have tons of headroom. With 4 Yamaha Pro-Audio Amps@ 350 watts per channel each going through a Richard Grey power supply, two 15 inch HSU Subs and two JBL Studio 590's with the 570's as surrounds including center, it gets very loud and clean. More than enough volume.

So I have a Very budget onkyo 5 channel receiver and it doesn’t have the option to switch the volume to relative so I’m stuck with 0-100, now I’ve heard that 80% percent is equivalent to 0db is that true?

Yo yo

dirac tunned my system at 89dbs any ideas?

My Sony hors from 0 to 73 on the volume scale. How fo i calibrate that?

Having trouble accessing digital copy of sact

Michael makes absolutely no sense when it comes to not being able to create an even response throughout the whole room. You definitely can and just because Michael can't do it, doesn't mean it's not done all the time.