How use SPL on an Denon 4800

[Razer]

Hi,

I went out and bought a radio shack digtal SPL reader. I also bought the DVD copy of Video Essentials now when watching that and from what I read here I'm suppose to get my speakers to a level that reads 76 db. My question is what volume level should my Denon 4800 be on etc so I could get the right settings for my speakers. So what I need here is a full run through on how to use an SPL meter and get the correct settings. Thanks you guys in advance.

[jhawk92]

Razer-

I have the same set-up you do. For the SPL, you need to set it on C-weighted, slow response. That will yield you the best mode for checking. The 4800 has a built-in program that you can use as part of the set-up which will allow you to calibrate the SPL at 75dB, which is what most manufacturers recommend. Just run through the program, and point the meter "up" so the silver microphone points towards the ceiling. Then it is just taking the time to tweaking the 4800 until the meter reads 75. The 4800 manual is pretty good while working on this. However, you must use a composite video cable between your receiver and TV so you can see the on-screen menus. If I remember correctly (manual at home), the menus only work in composite, not S-video and definitely not in component.

I don't know much about the Video Essentials DVD. I got the Avia disc for Xmas and was playing with it this weekend and like it alot. I do have one question for the board. Denon and many others recommend calibrating at 75dB, yet the Avia disc said 85dB was better, but 75dB could be used. Other than 10dB extra, what is the main difference?

Hope this helps. Good luck!

[myram]

When setting up your speakers using a set-up disc, you should have the volume on your 4800 at 00 (just like when the internal test tones are on).

I used AVIA to calibrate my system, and I did it to 80db with the sub at 85db. I found that having the whole setup at 85db and the sub at 90db was too dangerous( risk of hurting something).

Now as far as why AVIA recommends 85db, and VE recommends 76db, and manufacturers recommends 75db.....I have no idea why, but I have read an explaination somewhere at Home Theater Forum before but I can't remember it.

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Home Theater Page

[aab3rd]

I believe that it is because AVIA has their input signals turn down for less distortion (or something like that).

[toddvj]

You should use the test disc, not just the internal program in the 4800. That allows you to take the full path from Source to speakers. If you skip the source altogether, the input levels might vary from the DVD player to the receiver. Check to see if the Denon saves your settings for different inputs/sound fields.

[jhawk92]

Ok guys, thanks for the inputs. I'll have to read through the manual this weekend and see what I can come up with.

Myram-

Thanks for the heads-up on the 80dB vs 85dB level. I'll keep that in mind as I tweak.

[Mike Lindsey]

Razer,

I also have the 4800 and Video Essentials DVD. If you are looking for an explanation of how to calibrate, I got this off of the hometheaterforum (written by one of the moderators - Vince Maskeeper) a while back and have been using it as a reference ever since. The thread in question is no longer but here is what he had to say:

He explained that reference level is considered to be setting your speakers so that the LOUDEST possible sound coming out of any one measures 105db in Sound Pressure at the listening position in your room.

Now, how do you do that?

Well, someone could record a disc with a tone on it for you that is encoded as loud as possible -- you could play that tone in your room and measure it with a meter and set your receiver so that your speaker plays at 105db.

You COULD do that, but it would probably be a very, very unpleasant experience. No one wants to be blasted with full volume just to set his or her speakers.

So, the guys making the test tone discs said "Hey, why don't we just make the tone so it is a specific amount lower than maximum, and the guy using it at his house can just calibrate to the lower level!"

And thus they did. Video Essentials (VE) created a tone that is exactly 30 steps below maximum. Since we said maximum was supposed to be heard as 105db in your room, 30 steps below 105 is 75. So since you know the tone on VE is 30 steps below full level, you can measure that to be 75db in your room and achieve the same result! Now you would have it set so that the loudest sound would be 105db.

quote:

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From what I understand, Ref level is 00db on the receiver volume??? 00db is loud in my small apt (normally listen to -20 to -30 with each channel level set to 0db and mains and center set to small).

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Okay, here is where it gets a little tricky. Two points to remember:

1) Ref level just means calibrated so that the maximum level is 105db peak in volume in the room at the listening position. The position of the volume knob really means nothing.

Think about it this way - if you moved your current receiver and speakers into your favorite concert hall, and set it up on the stage and sat in the back row, the volume knob would have to be much HIGHER to get the same sound level to you WAAAAY back in the back row. More so, imagine taking the speaker system you see traveling with an arena rock band like Aerosmith. If you set that up in your living room - it would probably not take much to get your room really loud!

The point is - the key to ref level is OUTPUT. It is a measured output. If your volume knob ends up at 00 for ref level then great. If not, it could be at -04 or +03, or whatever.

My Denon allows me to adjust every channel, including the front L/R speakers, in the speaker setup menu. So I have set my volume knob to 00 and then adjusted all the speakers so that they measure correctly. I did this just for ease of use on my part (00 is easy to remember) -- I could have easily set the knob to -05 and adjusted the speakers to that point.

Some receivers don't let you adjust the R/L speaker - just center and surrounds. In that case, you simply adjust the volume knob so the L/R speakers measure correct and adjust center and surrounds around that. Again, in either case - where the volume knob ends up is correct - no matter what it reads. Just take a note of it.

2) The second point you need to keep in mind is this: Ref level is not necessary. Most, if not all, HTF members listen most of the time below ref level...Ref level is pretty loud.

Note by me: That's because they're not using Klipsch speakers.

The real key to calibration is to match all the speaker levels in SPL - making them even. It's good to also know where the REF LEVEL position on the volume knob is - but I usually find myself hovering somewhere between -05 and -10 of ref.

Again, the big key is to calibrate to match speaker output levels -- beyond that is YOUR HOME THEATER, adjust the volume knob to where you are comfortable listening. That's why the volume knob is there!

quote:

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From what I have read on this site, you are supposed to set receiver master volume to 00db and then calibrate speaker and sub levels to 75db on the SPL. Let's say the level I listen to is more like -20 to -30db, is this considered "my reference" master volume, and so I would set master volume to this point, then calibrate and adjust speaker and sub levels to reach 75db on the SPL meter? Or, if I listen lower than reference level...do I calibrate to a point different than 75db?

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What I would do is this:

1) Set the volume knob to 00

2) Adjust the levels using test tones and the SPL meter. If using VE, all tones should measure 75db. If using Avia, they will measure 85db.

3) You now have a system calibrated so that 00 is dolby ref level. Adjusting the volume knob will adjust all the speakers evenly - so you can now adjust the volume to the -10 or -20 position you normally listen at.

You don't need to specifically calibrate for where you plan to listen. In fact, if you tried to set the volume to -20 and adjust the channels to 75db, you probably couldn't get them to go high enough (again, he wasn't thinking of Klipsch when he said this). And even if you could, your -20 position would now be set so that it was ref and you'd probably want to turn down to -40 when you want to listen to it.

Keep in mind REF LEVEL will measure output. Just set it up so that 00 is correct and then adjust the volume to where you are comfortable listening...

There you have it,

Mike

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My Music Systems

This message has been edited by Mike Lindsey on 01-04-2002 at 01:29 PM