Just got SPL, now figured that something is wrong with my system! Help please!

[Bloodstriker]

So I received my SPL today and tried to calibrate my system with Avia. First of all, I have to say that the SPL is great - don't know how I lived without it.

But after running some tests, I think I might have a problem on my hands. Something is not working right in my system.

So here's the scoop: (please bear in mind that the terminology I use might not be correct, due to my newness to this hobby).

So I tried a LFE sweep and watched the SPL. It seems that I have huge drop offs at certain frequencies - at around 90-80Hz, 60Hz, and the sub is soundless from 35Hz and below. I'm not too worried about the 35Hz and 60Hz as that's probably the bottom limit of the sub and a room/placement issue. It's the 80-90Hz that I'm worried about. I have the crossover set to 80Hz, LFE only, used Avia to check the phase. Now shouldn't my fronts be able to do 80Hz without a drop like that? It's more than a 10 dB drop!

Okay, now to my big issue. There's this one test where you set the sub to match each speaker - i.e. It plays the front left, then the sub and alternates so you can make sure it matches. Now, when I do this, each non-LFE channel shows up at around 75dB, but the sub is at different volumes for each channel.

So for example, during each test, it would show something like this:

1) Front Left - 75 dB / Sub - 78 dB
2) Center - 75 dB / Sub - 73 dB
3) Front Right - 75 dB / Sub - 70 dB
4) Surround R - 75 dB / Sub - 60 dB
5) Surround L - 75 dB / Sub - 62 dB

I'm guess that something is really wrong here. I'm not sure why the sub volume is changing in each test? The sub volume / AVR volume / Sub position was not adjusted between each test, and the SPL was in the exact same position.

Could this point to my AVR having problems?

I don't think the problem is the sub. As puny as it is, during each of the 5 tests, the sub would give a consistent reading for each channel test. (i.e. the FL stayed at 78 each time I tested it, and the SL stayed at 62 dB each time I tested it).

Does anyone have any suggestions?

 

[mike c]

if i'm not mistaken, there shouldn't be any output from the subwoofer when each non LFE channel is being played.

are you using a disc to play the tones/waves? or are you using the receiver test tones?

what are your speaker settings? speakers to small? LFE to sub only? crossover? (does the denon 2802 have a variable crossover? if not, what is the fixed crossover?)

 

[Davemcc]

Okay, now to my big issue. There's this one test where you set the sub to match each speaker - i.e. It plays the front left, then the sub and alternates so you can make sure it matches. Now, when I do this, each non-LFE channel shows up at around 75dB, but the sub is at different volumes for each channel.

I found this exact same thing on my system. I don't know why it happens or what you can do about it. Rest assured that you are not alone in this experience and it is not likely an AVR issue.

On the 80-90Hz issue, be sure the crossover on the back of the sub itself is turned as high as it can go so the sub and AVR crossovers don't interfere with one another.

 

[Tomorrow]

I've not seen the test you mentioned on Avia. Is this sub/speaker matching test part of Avia or the Denon?

But I wonder....is it possible that your front left is further away from you than the front right...with the center mid-distance, and the surrounds closest to the listening position? It almost looks like the Denon is trying to make up for distance issues, or has something goofy going on.

Weird.

 

[GlocksRock]

I know what you are talking about, and I think the only reason they have lfe on all the channels is for when you may have a sub hooked up to those channels, such as if you are using speakers with built in subs (such as some Definitive Technology speakers), you can adjust the lfe on that channel. I think I remember reading somewhere in the setup menu for the avia disc that you really only need to calibrate your sub using the front left channel.

 

[Joe Schmoe]

Now, perhaps, you understand why I don't own an SPL meter. I use my ears to calibrate because it is my ears that will appreciate (or criticize) the result.

 

[Tomorrow]

Now, perhaps, you understand why I don't own an SPL meter. I use my ears to calibrate because it is my ears that will appreciate (or criticize) the result.

My ears are too dumb to do anything without the help of my not-quite-as-dumb Yamaha/DVE/SPL Meter. I seem to get better results with the Yammie, especially with peq.

 

[Bloodstriker]

I've not seen the test you mentioned on Avia. Is this sub/speaker matching test part of Avia or the Denon?

But I wonder....is it possible that your front left is further away from you than the front right...with the center mid-distance, and the surrounds closest to the listening position? It almost looks like the Denon is trying to make up for distance issues, or has something goofy going on.

Weird.

It's a test from Avia. I believe it's under "Subwoofer Tests>Front Left." It can't be the receiver trying to adjust distance, because the actual 5 channels all match in dB in this test. It's the subwoofer's volume that's changing in each test, which is really weird.

Davemmc:

I guess it makes me a bit more relieved to hear that I'm not the only one experiencing this. There are only 3 possibilities of where the problem lies: 1) AVR 2) Avia 3) Supposed to do this, but don't know why.

As for the 90Hz issue, the sub crossover is currently set on max.

On another note, after using Avia to calibrate the sub, I can barely hear it during a movie. I'm guessing that the sub could be turned about 3 dB or so?

Sigh, this hobby gets more and more complicated everyday.

 

[agarwalro]

the SPL is great

We all love SPL here...

It's the 80-90Hz that I'm worried about. I have the crossover set to 80Hz, LFE only, used Avia to check the phase. Now shouldn't my fronts be able to do 80Hz without a drop like that? It's more than a 10 dB drop!

This is probably a placement/ room response issue. Try playing around with the speaker location, toe-in, channel trims, etc. Also, your speakers might have flat response in the +/- 3dB range, but to achieve the same in the room will require electronic and physical room response correction. IMHO, +/- 10dB in the room is not bad at all... for a start .

the sub is soundless from 35Hz and below. I'm not too worried about the 35Hz and 60Hz as that's probably the bottom limit of the sub

Unless you have a very small sub, it should still have some output <35Hz. What do you have?

Okay, now to my big issue. There's this one test where you set the sub to match each speaker - i.e. It plays the front left, then the sub and alternates so you can make sure it matches. Now, when I do this, each non-LFE channel shows up at around 75dB, but the sub is at different volumes for each channel.

So for example, during each test, it would show something like this:

1) Front Left - 75 dB / Sub - 78 dB
2) Center - 75 dB / Sub - 73 dB
3) Front Right - 75 dB / Sub - 70 dB
4) Surround R - 75 dB / Sub - 60 dB
5) Surround L - 75 dB / Sub - 62 dB

I'm guess that something is really wrong here. I'm not sure why the sub volume is changing in each test? The sub volume / AVR volume / Sub position was not adjusted between each test, and the SPL was in the exact same position.

Could this point to my AVR having problems?

This test is designed for people who have full range speakers with active subwoofers and subwoofer gain control built into the same physical speaker. Martin-Logan SL3 is one such speaker. When sending said speaker full range signal and using the gain control on the sub, this test helps ensure that the active sub level matches the level of the rest of the speaker.

In your case, since the sub is seperate from the speaker, ignore this test. As long as all the speakers play 75dB independently, you are good.

 

[Bloodstriker]

The sub I'm running is a PSB Alpha Subsonic 5 (10" and 65W), but I've already ordered the SVS PB Ultra 13.. so I'm guessing it'll arrive in the next few months.

Here's another question - when calibrating with the SPL and Avia, what should the volume on the AVR be set at? do set it to "00" and calibrate it to 85dB? Or do I set the AVR to my normal listening level (i.e. "20") and calibrate that to 85 dB?

 

[GlocksRock]

You set the AVR to 0 which is reference level and with Avia, you would calibrate to 85 db, if you are using your receivers test tones, you calibrate to 75 db.

 

[agarwalro]

The sub I'm running is a PSB Alpha Subsonic 5 (10" and 65W), but I've already ordered the SVS PB Ultra 13.. so I'm guessing it'll arrive in the next few months.

Oh boy, this icon "" will not be able to express the grin on your face when you get the Ultra...

Here's another question - when calibrating with the SPL and Avia, what should the volume on the AVR be set at? do set it to "00" and calibrate it to 85dB? Or do I set the AVR to my normal listening level (i.e. "20") and calibrate that to 85 dB?

The Master Volume on the AVR is really just a relative volume setting and does not mean much by itself. If you set the Master to 0.0 dB, and then adjust the channel trims so that the speakers now play 75dB (or 85dB for Avia disc), 0.0 becomes your reference volume setting. Now, if you are watching a movie at -6.0, you are listening at 6dB below reference volume.

Alternately, if you set the Master Volume to -10.0 and now do the calibration, -10.0 becomes the reference volume setting. To get 6dB below reference in this case, you will need to keep the Master Volume at -16.0

 

[Bloodstriker]

Thanks agarwalro! That's good information. I didn't realize that each increment on an AVR is actually one dB. I guess it'll recalibrate it to something that I can remember so I know how loud I play things. I think I set the reference to something strange like -8 or -6. I have no idea.

I guess my normal listening levels for movies is in the area of 65-70dB. How about you guys?

 

[ParadigmDawg]

70-75db during the 1st month of having a new system, 55-60db now with the sub +4 hot.

Thanks agarwalro! That's good information. I didn't realize that each increment on an AVR is actually one dB. I guess it'll recalibrate it to something that I can remember so I know how loud I play things. I think I set the reference to something strange like -8 or -6. I have no idea.

I guess my normal listening levels for movies is in the area of 65-70dB. How about you guys?

 

[Joe Schmoe]

My typical master volume setting is -26dB, but I have no clue what that translates into in actual loudness. It is not too loud, though (I like talking to sound like talking, not yelling.)

 

[agarwalro]

I didn't realize that each increment on an AVR is actually one dB.

Most receiver I have seen have 0.5dB steps.

I guess my normal listening levels for movies is in the area of 65-70dB. How about you guys?

My calibration is for Master Volume at -15.0dB with the sub +3.0dB for effect. I usually listen at -12.5 for DD and -17.0 for DTS.

 

[mtrycrafts]

The sub I'm running is a PSB Alpha Subsonic 5 (10" and 65W), but I've already ordered the SVS PB Ultra 13.. so I'm guessing it'll arrive in the next few months.

Here's another question - when calibrating with the SPL and Avia, what should the volume on the AVR be set at? do set it to "00" and calibrate it to 85dB? Or do I set the AVR to my normal listening level (i.e. "20") and calibrate that to 85 dB?

Is that receiver THX? As best I know, THX receivers move the master automatically.

If not, then the question is do you have numbers above 00 in the + territory?
If, yes, with that DVD, since I believe the test tone is -20dBFS, I would use
-10 and set the level at 75 dB spl. this is so you don't have to expose yoru ears to 85 dB spl constant tones. You could though wear ear plugs and when no one is home, do it at 00 and 85dBspl. this will be your theater reference level. Most use much less at home as reference would be just too loud.

 

[FreeHomeTheater]

had the same problem myself. thanks for the good info.

 

[Bloodstriker]

Just recalibrated at -10 to 75dB. One strange thing I noticed is that the test tone from the AVR varies from the Avia disc. I tried calibrating to the AVR test tones, and set everything to 75db. Once I popped in Avia and checked the levels, they were all different. My Left and right matched, my center was 2 dB too high, my rears were 1 dB too high.

I then recalibrated using Avia again and kept it that way. I'm thinking that the DVD is more representative of a movie since both are coming from the same format?

Strange. I would have thought equal level across speakers means equal level, regardess of how it's tested.

 

[GlocksRock]

Just recalibrated at -10 to 75dB. One strange thing I noticed is that the test tone from the AVR varies from the Avia disc. I tried calibrating to the AVR test tones, and set everything to 75db. Once I popped in Avia and checked the levels, they were all different. My Left and right matched, my center was 2 dB too high, my rears were 1 dB too high.

I then recalibrated using Avia again and kept it that way. I'm thinking that the DVD is more representative of a movie since both are coming from the same format?

Strange. I would have thought equal level across speakers means equal level, regardess of how it's tested.

I had this same exact problem... you can read all about it in my thread about calibrating the surround back speakers... I just ended up setting all my levels with the receivers test tones and so far I like the results better than when I used Avia.