What is Reference level and how is it determined?

[Johnny Vinyl]

Enlighten me please, because I'm totally lost as to what this means and how to figure out what that "Reference Level" is with my own system.

 

[thedudeabides]

How about when you can hear everything your system is doing avoiding excess volume and distortion. That would include "overloading" the room and exciting resonances. I note volume level for each of my CD's using those parameters.

Remember that "reference", in this case, is entirely subjective.

 

[andromedaaudio]

Reference level is essentially the essence of all audiofile debates since the invention of amplifiers , this reference determination debat will go on for centuries to come

maybe it could be best described as an enigma or paradox

 

[Johnny Vinyl]

How about when you can hear everything your system is doing avoiding excess volume and distortion.

Remember that "reference", in this case, is entirely subjective.

I hear people referring to this with their 5.1 HT systems all the time and I was wondering what they meant.

 

[garylkoh]

I hear people referring to this with their 5.1 HT systems all the time and I was wondering what they meant.

If for HT systems - THX certified receivers should have a '0' level on their volume controls that represents the volume level used in studios. IIRC it's 85dB with 20dB of headroom.

 

[FrantzM]

Reference has actually a standard definition. It is not subjective. To make is simple .. This is the SPL at the seating position using Full Band Pink noise. 85 dB is that number. You will often see 75 dB but this is used because 85 DB and 20 dB headroom from both channel suppose the ability to play 105 dB from each channel at the seating position.. That can be loud and a strain for most amp/speakers combination leading to distort or worse. I would add that Reference level suppose also that the LFE transducer be able to reproduce 10 dB over the 105 dB at the listening position i-e 115 dB at the listening position. This is very difficult SPL level to achieve and frankly the end result is very loud even for movies watching.

 

[Johnny Vinyl]

Reference has actually a standard definition. It is not subjective. To make is simple .. This is the SPL at the seating position using Full Band Pink noise. 85 dB is that number. You will often see 75 dB but this is used because 85 DB and 20 dB headroom from both channel suppose the ability to play 105 dB from each channel at the seating position.. That can be loud and a strain for most amp/speakers combination leading to distort or worse. I would add that Reference level suppose also that the LFE transducer be able to reproduce 10 dB over the 105 dB at the listening position i-e 115 dB at the listening position. This is very difficult SPL level to achieve and frankly the end result is very loud even for movies watching.

This is why I asked. If it's that loud and perhaps almost unbearable, why is it considered reference. I must be missing something.

 

[Garth]

...

 

[JackD201]

This is why I asked. If it's that loud and perhaps almost unbearable, why is it considered reference. I must be missing something.

Don't worry about it John. The pink noise will be unbearable but when you go to program material, the vast majority of the time, it won't be. The reference level is there so monitoring systems will be calibrated the same way for work mainly. That way one can hop from station to station or suite to suite. For recreational purposes set it at the reference when calibrating but use the volume at your own preference.

Is 85dB arbitrary? Legend has it that normal speech at ~2m has peaks in the formants at 85dB. I could never find the source of this little nugget but using a rat shack spl meter on friends, it is pretty close. Maybe it's not so arbitrary after all.

 

[mojave]

In TV and movie studios, the monitoring gain when listening to the mix has been standardized. The European Broadcasting Union (EBU) uses a standard alignment called R68. In the United States the Society of Motion Picture and Television Engineers (SMPTE) uses a standard known as RP155.

The Reference Level standards are used to make sure that listening in various sound rooms, control rooms, or theaters remains consistent. Typically -20dBFS bandwidth limited pink noise or -20dBFS full range pink noise is used for calibration.

Because room size changes the apparent loudness of the mix, there are variations in level based on cubic feet of the room. A theater will typically be calibrated to 85 dB with -20dBFS while a studio or home can be calibrated to lower levels.

Most home theater receivers, during calibration, will set the master volume level to 0 to represent Reference Level. One then might listen at -20dB or -15dB on the volume control. With it set to 0, the peaks should get as loud as 105dB for the speakers and 115dB for the subwoofer system.

Reference level really needs to be reset on receivers using a calibration disc such as Disney's World of Wonder or the AIX Blu-ray Calibration disc. Here is how several receivers compared using their own internal tones and calibration:

Nyal Mellor has a good write up about Reference Level on his website:
THX REFERENCE LEVEL EXPLAINED

 

[mojave]

This is very difficult SPL level to achieve and frankly the end result is very loud even for movies watching.

The 85dB calibration is only for a theater. Below are the recommendations based on room size.

In a proper home theater, Reference Level is easy to listen to and very comfortable for movie watching. Regarding difficult, I can go +10 over reference with no problem and have been in systems that can go +20. Peaks are capable of 130-140 dB. In my own room, I need to listen at about -5 dB but I don't have a fully treated listening room.

 

[caesar]

Reference level, huh? Let's be completely honest: In a luxury industry, and high end audio is a luxury industry whether people admit it or not (and if not, they are lying to themselves), companies (through reviewers) construct mystique and fantasy worlds. They house their product in colorful/ glossy/ shiny cases, try to get celebrity reviewer endorsements, and explain their product's superiority using (pseudo) scientific language while marketing their product. They keep prices high: many don't buy anything unless they can pay a lot. High prices convince the product is worth having. They play to your ego: you can't afford, you are not worthy, therefore, you want it very much!

High end audio consumers buy anything in quest for great sound. Kind of like your wife/ partner buying that expensive face cream.

 

[Robh3606]

Reference level, huh? Let's be completely honest: In a luxury industry, and high end audio is a luxury industry whether people admit it or not (and if not, they are lying to themselves), companies (through reviewers) construct mystique and fantasy worlds. They house their product in colorful/ glossy/ shiny cases, try to get celebrity reviewer endorsements, and explain their product's superiority using (pseudo) scientific language while marketing their product. They keep prices high: many don't buy anything unless they can pay a lot. High prices convince the product is worth having. They play to your ego: you can't afford, you are not worthy, therefore, you want it very much!

Hello Caesar

What does that have to do with HT reference level?? HT in comparison is very affordable.

This is very difficult SPL level to achieve and frankly the end result is very loud even for movies watching.

Hello Frantz

Geez I hope not!! Any system worth calling a system should be able to deliver 105db peaks with relative ease. I designed my set-up for 115Db peak capability to give me an extra 10db of headroom above reference level. It wasn't all that hard to do. Just start with speakers with higher than average sensitivity and good power handling.

Rob

 

[caesar]

Hello Caesar

What does that have to do with HT reference level?? HT in comparison is very affordable in comparison.



Geez I hope not!! Any system worth calling a system should be able to deliver 105db peaks with relative ease. I designed my set-up for 115Db peak capability to give me an extra 10db of headroom. It wasn't at all hard to do.

Rob

Not sure what you or anyone else is talking about. I believe this sub-forum is titled "general audio discussions". Read the first post, and you got my reply. If there is another reference level, why not post it in the appropriate forum to avoid language ambiguity?

 

[jfrech]

Reference Level=when your wallet is empty and your credit cards are maxed out...

 

[Robh3606]

Hello Caesar

From the OP post 4

I hear people referring to this with their 5.1 HT systems all the time and I was wondering what they meant.

Did you read the thread?? Very clear what reference level he is asking the question about.

Reference Level=when your wallet is empty and your credit cards are maxed out...

LOL

Rob

 

[thedudeabides]

Any system worth calling a system should be able to deliver 105db peaks with relative ease.
Rob

Rob,

With all due respect, your peak level may be far different than others.

What I've found over the years, is that the better the system (higher resolution, clarity, etc.) the lower the level one requires to enjoy the system.

Even though my system can do this, I've never reached that peak. Hurts my ears not to mention potential long term hearing damage.

Best.

 

[Johnny Vinyl]

I'm still unclear about what it all means, but I'm sure it'll sink in after reading it a few times. prerich found this from Nyal's site.

http://www.acousticfrontiers.com/2013314thx-reference-level/

 

[Johnny Vinyl]

Most home theater receivers, during calibration, will set the master volume level to 0 to represent Reference Level. One then might listen at -20dB or -15dB on the volume control. With it set to 0, the peaks should get as loud as 105dB for the speakers and 115dB for the subwoofer system.

Reference level really needs to be reset on receivers using a calibration disc such as Disney's World of Wonder or the AIX Blu-ray Calibration disc.
[/B]
Nyal Mellor has a good write up about Reference Level on his website:
THX REFERENCE LEVEL EXPLAINED

Thank you. I think I'm getting it!

 

[FrantzM]

Reference level, huh? Let's be completely honest: In a luxury industry, and high end audio is a luxury industry whether people admit it or not (and if not, they are lying to themselves), companies (through reviewers) construct mystique and fantasy worlds. They house their product in colorful/ glossy/ shiny cases, try to get celebrity reviewer endorsements, and explain their product's superiority using (pseudo) scientific language while marketing their product. They keep prices high: many don't buy anything unless they can pay a lot. High prices convince the product is worth having. They play to your ego: you can't afford, you are not worthy, therefore, you want it very much!

High end audio consumers buy anything in quest for great sound. Kind of like your wife/ partner buying that expensive face cream.

Huh Caesar .. What's up?!? I could not have written it up any better