I keep reading posts about using a meter to set up speakers properly and how it will eliminate many initial sound problems.
What I can't seem to find is what am I doing with this meter? I don't want to look like Spock walking around the living room searching for the Wavelings. Is there an article (I can't seem to find one) that explains exactly what I chould be looking for?

I will be setting up a 60/500 (7.1) in my new home. My biggest problem is that I can't order them for two more weeks. My home is about 8 weeks from completion and the last thing I want to do is stare at new speaker boxes without being able to do anything about it.

Here's a pretty decent article describing what the SPL is measuring and how it relates to setting up a room for audio ...
SPL Meter ... hope it helps.

Welcome aboard and congrats with the new digs Lohengrin.

buy something like this from radio shack:
http://www.radioshack.com/product/index....rentPage=search

the meter has a knob at the top that you turn to the appropriate DB level. If you turn the knob to 70 db it will read everything from 60 db - 80db. Most people calibrate their system to about 75 db so leaving the meter on the 70db mark will work fine.

Either sit in the primary listening position and hold the meter or place the meter there with a tripod. Make sure the meter is on "C" weighting not "A". Play test tones for each speaker through your receiver,and adjust the channel levels so that each one reads 75 db. Some people choose to bump up the sub by 5db.

What receiver do you have?

*Cue JohnK with his technical research paper links

Just curious...

Is there any point in doing this if you have for example a Denon 3808, and use Audyssey Multi EQ XT?

Even though my Denon 2805 has auto setup/mic, I still go back and verify SPL levels, distance, etc. Many times the receiver is a little off. I addition, I never use built in EQ features of receivers, to me it makes good Axiom speakers sound worse, and changes the original manufacturers design.

More info (some actually relevant to topic):

The room is about 4000ft3 (17l x 24w x 10h) with long end opening into the dining room. Seating is 14' from 65" tv (view axis is 17 side).

I am using a Pioneer VSX-1015TX (7.1, 125w/ch).

80% movie/television, 18% music (jazz, classic rock, classical), 2% Tiger Woods Golf.

One more thing.

Even though the receiver has the built in mic for set-up I would prefer (based on info read here and elsewhere) to do it manually.
I also have Avia 2.

You should be set then ... the Avia disc should include a step-by-step walk through for calibrating with your SPL meter.

Ahh, I have never even looked at the audio section. I used it to calibrate my television.

I will look it over and post any questions it leaves unanswered.

Thanks for all of the replies.

I ran the Audyssey first then double checked with an spl meter, the Audyssey was right on for the speaker setup.

Martin, if you have a receiver such as the 3808 or the many other units that have auto calibration systems, then no, in my view there's no good reason to do the calibration manually. The auto calibration done with the receiver's built-in SPL meter and processor should be at least as accurate as using a separate external SPL meter to assist in making a manual calibration. The added factor of human error in the manual calibration would make it likely that any difference in the results would mean that it was us, not the receiver, that was "off".

This doesn't mean that an SPL meter isn't useful, and I frequently use my RS digital SPL meter to check minimum, average and maximum sound levels when I play various program materials.

Ok, but it is possible to let the 3808 just calibrate the distance and level, and not apply any equalizer?

For example when using pure direct button, I would assume that nothing at all is applied? But this mode only supports stereo correct?

Correct, and yes, it should be kept in mind that Audyssey and the other calibration/room equalization systems do have those two entirely separate functions. The calibration can be used and not the room equalization.

On the Audyssey equalization function itself, however, I recently read the current issue of The $ensible Sound magazine, in which David Rich ran very extensive tests on the Onkyo 705 and 805, including the Audyssey equalization. In addition to praising them in general for their excellence as amplifiers, Dr. Rich's graphs and listening tests relating to MultEQ XT led him to comment that "The excellent flattening of room effects in the 100Hz-500Hz region improves sound quality for any speaker" It's something that calls for careful experimentation.

So the recommended setup is to run the auto calibration and leave it with that as it should generate the best response and sound?
Im planning to buy the 3808 soon, but Im still trying to figure out some stuff about it.
For example how it works with SACD DSD signal over HDMI. Some say that it must convert to PCM if you want to use Audyssey/MultEQ. Also Im trying to figure out what all the EQ modes like cinema and so on are really doing opposed to just running the normal dd/dts modes.

No, that certainly wouldn't be my recommendation. With the 3808 and other receivers which use Audyssey MultEQ XT, it's a major feature(and expense item)of the unit, so part of its function shouldn't be simply discarded. Initially, maybe just the calibration can be done, but the room equalization should then be given a thorough test later on. Dr. Rich's tests and the reports of many users indicate that benefits are to be had.

I thought that was what I wrote. Im not sure exactly how this works, but I thought you just run the calibration and then the reciever sets everything up for you including EQ etc...
Also I just wondered, how do you set the volume knob on the sub before calibrating?
And what volume should you turn up to on the reciever when using a SPL meter?

If you use the auto setup and run audyssey then the denon will automatically adjust channel levels during the set up... there is no need to touch the volume knob.

If you manually calibrate then just adjust the channel levels and not the main volume as well. I left the main volume at 0 db (its default posistion in the manual setup menu for the denon) during the entire manual set up and just adjusted the individual channel levels.

I would highly recommend enabling Audyssey. Have a look at this thread over at AVS: http://www.avsforum.com/avs-vb/showthread.php?t=795421

I have the Onkyo 705 and really like the difference Audyssey makes in my room.

definitately give it a try. I tried it out and found that I like things better without it... May give it another shot later on in the future though.

I think using an SPL meter gives the system that little personal touch, and knowing that it is setup to the best it can be is a great feeling.

Can someone answer those questions, I too would like to know!

I understand you leave your LFE setting @ 0db on the receiver, but before running Audyssey/YPAO, how do you set the volume knob on a EP500? In my case, the knob is almost at mute, I'm at 6'oclock because when I tried 9-10'oclock as Alan suggested in his article, YPAO was unable to calibrate properly the sub and it was booming, it was very loud.

I actually set the sub to "0" on my reciever and calibrated the sub manually to 75 db. This make it easy to know exactly where 75db is, if I want a little less bass, bump it down to -5, if I want to run it a bit more, up to +5. But I always know where 75db is with the rest of my system. Makes it easier to play with sub settings and being able to put it back to normal.

The sub should be set no more than half way. You can tell if it was too high by looking at the trims after running Audessey. If the sub trim is a large negative number (-10 or more), you should adjust the sub's volume down and rerun Audessey.

On the Onkyo's (and I assume the Denon), the volume makes no difference. The test tones are set at -30db from reference (or 75db actual).

Kk this makes sense. On my Yamaha, you have to adjust the volume manually when running the test tones, while in automatic calibration (YPAO) I suppose it must be something similar to what you've mentioned (-30db from reference).

On the Denon, the test tones are indeed preset levels and adjustment is strictly done per speaker up or down to adjust as you need to reach your desired levels on the SPL meter.

While not trying to disagree but whenever I read this, the first thought to cross my mind was these poor fellas who's manual efforts were useless during this computer generated and controlled ride ... Along for the ride.

Frightfully scary.

As I anxiously wait for fedex to ship my speakers I have a related question.

Is the AVIA 2 a good calibration DVD along with the radioshack SPL meter, or do people have other recs??

Thanks again

Sam
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Denon 3808-M80s-VP150-EP350v3-QS4s

Avia has some nice features to easily test phases and transitions that do not require any expertise whatsoever as they are meant to make "problems" cleanly audible.

The rest of calibration is more on the bass management-side. For that, the Avia disk will give you some initial elements that are worthwhile.

I will let other people who did more expirement fill you in on additional stuff you can do for bass (I am one of those lucky bastard who happens to have a room with nice smooth bass, so I have not spent much time correcting!).

For the highs, just avoid flat reflective surfaces. Paintings, carpets, bookshelves on the walls can help taming fast-reflecting highs.

I find DVE(Digital Video Essentials) to go a little more in depth than Avia for audio set up, but that could just be me, Avia will give you what you need with some decent sweeps etc. The 3808 does a good job with Audyssey for seting up the speakers and then you can go into the curves and adjust them as you see fit. Something to note if you do use Audyssey, it will set the sub lower than most people want. It will set the sub to blend in so much that you won't know it is even on. It seems almost every one bumps the sub level up 5-6 db from Audyysey's settings, myself included.

I didn't find DVE all that useful for audio at all. For measuring and setting up your sub, I don't think you can beat REW. Its a free utility you can use on a PC in conjunction with a mic or spl meter to make in room measurements. You will see exactly where your peaks and nulls are.

I liked the sweeps and routines on DVE better than the ones on AVIA. Doing the set up through the 3808 is better than both and a very good place to start for tweaking after that.

I think I have put off using REW because I am afraid of what it might show

Thanks everyone. Now I just need to buy an SPL meter, install REW and take a deep breath and convince myself I can do this.

I will say that I have had to add a couple of db to my M80s and 4dbs to the EP350v3. Audyssey did only a decent job of calibrating the system. Maybe I should run the system again since I have moved and repositioned the M80s a little.

You could use mine if you were a bit closer to Wilmington.

I would suggest just sitting back and enjoy your system. I got all caught up in REW, Realtraps graphs, SMS-1, etc. You can drive yourself crazy trying to tweak this stuff. Just do an auto setup using Audyssey, verify the levels and speaker settings after the fact, and enjoy.

Meh, anybody can just sit down and enjoy. It takes a real pro to drive ones self crazy!!

From what I have read, the results of room treatments, if they are successful, can be dramatic. If you happen to have an ugly room like mine, it can be a never ending quest. We will see if I get anywhere or just drive myself crazy.

For the cost of a meter though, and if you are a DIY/tinkering kind of guy, its worth a try.

Hopefully dsbad and I will not get "all caught up".

Edit: There is a really good, if sometimes hard to follow thread, at hometheatershack.com by thewire where the outcome was good. Its in the REW forum.

If you moved the speakers after the initial auto setup, then you will need to do the setup again, it is that sensitive. Are you taking the readings with the mic from several seating positions? It appears to help smooth things out, if so this could be why you found you needed to adjust the M80s levels. The sub, well, Audyssey just strives for a flat response with it and has always set mine too low for my liking as well. You may also find that Audyssey will set the M80s to Large allowing for a full range speaker, which in turn, leads them to be set too low trying to keep the bass down to equal the upper end.

And take all of this with a grain of salt as I am very tired and it time for bed. I may want to change this when I get up.

Fred, I've been down the bass traps and acoutic panels path as well, long before you became a member. If you've looked at my website you would see pictures.

Yes, treatments did seem to make a nice improvement, if done correctly using the right material.

I've been a long time member at HomeTheaterShack, very familiar with the REW forum. Just running the software with your spl meter from one location does not resolve the rest of the room locations. Unless you plan to incorporate filters using a BFD or similiar device, it is unlikely you will see any positive outcome. The is similar to the video Ian talkes about on the benefit of using multiple subs on opposite walls to resolve frequency peaks/null issues. EQ'ing is not recommended.

So what you are telling Fred to do is buy at least one more sub, but even more desireable would be 3 more subs.

Donations are welcome.

I wish I could afford another sub, or even the parts for a DIY.

Yeah Jason, Since I've gone to a 600 and twin 350's I never have a use for my Velodyne SMS-1 digital sub EQ system anymore. I'll most likely sell it soon.

I'm not quite sure how to parse these two sentences as they direcly oppose each other. My current understanding is that applying filters using something like BFD will only treat a specific position, where as treatments deal with the basic issues in the room IF chosen and placed properly.

Unfortunately, the options for treating frequencies below 100 Hz seem to be either very bulky, or very finicky.

If you have any suggestions based on the info I have posted on my room, I would love to hear them.

I think they are the same. Applying EQ is basically the same thing as applying filters. They both only benefit the location where you took the measurements with the mic or spl meter. Neither have to do with treatments, those address the entire room.

4" of Owens Corning 703 or equivelant stratling all corners, including floor/wall and ceiling/wall do very well below 100hz. I actually built "Super Chunks" in my front two corners, basically cut the 703 into triangles to fill the corners does better than just statling the corners.

From specs I have seen, they seem to taper off fairly steeply below 80Hz. That was not your experience?

I wish I had lots of corners to fill. Unfortunately, I only have one and onehalf vertical corners. That leaves me with only the ceiling/wall interfaces to work with.

I just installed the superchunks and reflection panels and enjoy. I'm basing off the research from Ethen, the owner of Real Traps.

Here are some of my results with NO REW filters or EQ on the receiver or SMS-1.




This picture shows how the overall response improved just by adding my superchunk bass traps, no wall panels yet.

Are you noticing an even greater effect across the room (multiple sweet spots) or is it mostly located where you already concentrated your efforts?

Adding multiple subs, bass traps, and first reflection panels, has improved the response across all seating locations. If you calibrate using REW or the SMS-1, etc. from the primary seat, your only benefiting that location.

Thanks for the graph. Its nice to see some real world measurements. Looks like the superchunks did some interesting things below 100Hz.

I guess I just need to go out and pick up some 703 or similar and do some testing. As a quick and dirty test I can just put a couple of bales above the aquarium at the front of the room and see what that does.

I have 4 subs with an SMS-1 processor and I would totally agree location and acoustics are the most important elements in getting the smoothest bass response. I would, however, submit that the SPL meter drops off significantly in accuracy below 50hz so you won't get an accurate reading of that REAL DEEP bass. This was confirmed in Ian Colquhoun's tutorial on the subject plus a number of other manuals. The advantage of the SMS-1 in this particular case, to my hearing anyway, is it enables you to pump up that deep bass(provided your subs can handle it) and in turn, turn the overall volume down slightly to compensate. Although sirquack's graph is showing generally a balanced response, especially with room treatments applied, the deepest bass(25-40hz) will be masked by the upper bass frequencies since the ear still can't hear these lowest of frequencies as well especially at lower volumes. A similar principle was applied to receivers in the recent past that had a "loudness" control. This is strictly my opinion and in the end, it's all about personal preference anyway.

The SMS-1 is a great piece of equipment, especially for one sub, or multiple subs nearfield. The problem is the EQ adjustments you make change the response for all the subs connected to the single SMS-1 processor. If you have the subs on 2 or 4 opposite walls, you would really need seperate SMS-1's for each sub, or purchase their higher end model that lets you have seperate EQ settings for each sub.

Fred, also keep in mind those changes on the superchunk graph was just by adding the front corner bass traps. I have not done the rear walls, or floor/wall, or ceiling/wall.

Your correct Casey on Ian's statements, I believe that is one of the reasons he does not believe in EQ methods, just following Dr Toole's paper.