# Setting Target Level (10db LFE drop from player)



## jlafrenz (Jun 6, 2010)

I took a measurement of just my subs and noticed that they were quite a bit higher than the 75db mark. I thought this was a bit strange because I have manually leveled everything in my system to 75db (subs about 78db). After thinking about it for a minute, I realized that it may be that my subs are measuring "hot" because they are adjusted to compensate for the 10db drop in LFE from my Blu-ray player. I have the Pioneer Elite BDP-05fd and I am running analog out. The 10db drop is a well known situation with this player. I assume that my measurements are accurate because of my adjustments and REW does not have any drop because it is simply using a test tone and measuring it directly. 

So My questions are first and foremost, am I correct in my thought process here? Do I need to set the target level to 85db so that the filters applied more accurately reflect what is happening in my system? I don't want to lose the SPL that I have right now, because I am really happy with it and adjusting it up would potentially max out some of the gains on the player or processor, which I want to avoid. Where is the ideal place to set the target level, during a part of the calibration or right before adjusting the filters?


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## jlafrenz (Jun 6, 2010)

Here are pics of the graphs if it helps. 

First Graph










Assign Filters










Optimise PK Gain


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## laser188139 (Sep 19, 2009)

There's no pic, probably because you don't yet have five posts. The post padding thread is here.


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## jlafrenz (Jun 6, 2010)

laser188139 said:


> There's no pic, probably because you don't yet have five posts. The post padding thread is here.


I just went there and posted so hopefully the pic shows up soon.


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## laser188139 (Sep 19, 2009)

It's a little hard to tell what is happening with the vertical scale compressed as it is. The recommendation is that the vertical scale be 45dB-105dB. 

Bill


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## jlafrenz (Jun 6, 2010)

I updated my original post with new pics that are the correct size.

So, back to my original post. Where do I need to set the target level?


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## laser188139 (Sep 19, 2009)

jlafrenz said:


> I took a measurement of just my subs and noticed that they were quite a bit higher than the 75db mark. I thought this was a bit strange because I have manually leveled everything in my system to 75db (subs about 78db). After thinking about it for a minute, I realized that it may be that my subs are measuring "hot" because they are adjusted to compensate for the 10db drop in LFE from my Blu-ray player. I have the Pioneer Elite BDP-05fd and I am running analog out. The 10db drop is a well known situation with this player. I assume that my measurements are accurate because of my adjustments and REW does not have any drop because it is simply using a test tone and measuring it directly. ...


Which receiver do you have? What exactly did you do to "compensate" for the 10dB LFE drop in the player? I take it you are using analog audio because your receiver does not accept HDMI, and you would rather convert lossless tracks to analog than pass DD/PCM over digital audio cables. 

The BDP-05FD thread suggests this is not a player issue, but rather an issue with some receivers that do not have the +10dB boost for the LFE channel over analog inputs. My Denon, for example, doesn't have this problem. Rather it has an option to undo the normal 10dB boost, by applying a -10dB adjustment when listening to DVD music that does not need it. In the same note, I see the advice to apply adjustments to the LFE channel in the player, otherwise you will mess up your bass balance for all your other sources. 

If you are applying trim adjustments to the analog outputs from the player, then the receiver won't be applying these to the REW test tones, and you would target 75dB as is done normally. If you are using the sub trim in the receiver to create a 10dB LFE boost that the receiver is not applying itself, you are stuck between a rock and a hard place. Any boost you create will apply to the bass outputs in the normal channels, and you will have too much, unless you set all the satellite channels to Large/Full range. Of course, while they are Large/Full range, the REW test tones would not be redirected to the sub, which you need to perform equalization. I'm not sure I have any advice on what compromise trim adjustment to make in a receiver that suffers the "LFE bug".

Bill


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## jlafrenz (Jun 6, 2010)

I have the Emotiva MMC-1. There is no bass boost to the LFE to make up for the 10db drop to the best of my knowledge. When I say compensated, what I mean is that I have adjusted the trim to +4 in the player itself and +6 in the MMC-1 to make up for the loss of LFE. I split the two as to avoid maxing out one or the other. I have then set the level on the rear of my subs accordingly so that test tones all match at 75db (78db for subs as I want a little more bass) on my SPL meter. My speakers are all set to small in the player and I have not used REW to test any of the speakers except the subs. I am only using the sub input on my multi-channel inputs which is receiving the signal from the PC/REW.


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## laser188139 (Sep 19, 2009)

I'm not quite sure why you are not using HDMI for lossless audio, unless your TV does not accept HDMI video. The MMC-1 appears to understand how to decode LFE correctly when you bitstream to it. The manual talks about a DTS LFE mode selection, where CINEMA is normal and MUSIC provides a -10dB reduction. So you could verify that whether your 10dB LFE adjustment is necessary by bitstreaming the digital audio to the receiver and comparing the level to the same test track using the analog audio cabling. The manual is clear there is no bass management of the 8-channel analog input, but my internet searches did not uncover a clear statement one way or the other on how it handles LFE. 

If you are go with the adjustment you describe, of +6dB in the MMC-1, then you want to adjust the target in REW up +6dB, from 75dB to 81dB. After all, the REW test tones see only the boost in the receiver, not the one in the player. That assumes you are still trying for a flat response, with the manual LFE boost. If you did not have the LFE issue, you might consider a house curve to raise the lower bass frequencies when listening at a typical volume, below reference level. With the LFE boost being applied to all bass, my guess is you don't need any further bass boost in a house curve. 

Bill


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## jlafrenz (Jun 6, 2010)

The MMC-1 has HDMI, but it is only a pass through for video. Are you sure your reading the MMC-1 and not the UMC-1?

Setting the target level up 6db makes sense and I thought about doing that. My only concern was that when actually watching a movie, the player would then be adding another 4db of gain to that signal and it might alter it or throw off my filters. I guess the best way to do it is try it out and then go back and measure (with the BFD and filters applied) what db my sub is measuring via the SPL meter using the test tones or a test disc in the player.


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## laser188139 (Sep 19, 2009)

You're right. I noticed the HDMI inputs on the MMC-1 and did not dig deeper to see if it actually decoded the audio. Apparently it expects a digital audio connection in parallel with the HDMI connection. Sigh. 

Thinking about it some more, I find I disagree with Ruined's suggestion that the LFE bug is not an issue with the BDP-05FD player. If the player is doing the bass management to mix the satellite channels with the LFE, it is responsible for the levels. 

The nice thing about Ruined's suggestion to do all the adjustment in the player, adding to the sub level out from the player and subtracting from the satellites, is that this leaves all the trims intact in the receiver. So you can also run digital audio from the player to the MMC-1, and if you listen to the Dolby track over bitstream, the MMC-1 should treat everything correctly and you will have the correct level mix of LFE and redirected bass. 

I see in a Panasonic BD30 thread of the same era that people had different opinions on how much boost to apply, as the full 10dB for LFE will overemphasize the bass in the redirected satellite channels. 

Regardless, my suggestion above still holds, that the 75dB target in REW should be adjusted for your sub by whatever amount you boost the sub trim in the receiver. 

Good luck,
Bill


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## jlafrenz (Jun 6, 2010)

Sigh is exactly right. There have been several times when I wished I had HDMI decoding. Once the new XMC-1 is ready I will, but that is another topic. I have tried setting everything to LARGE and I actually had it set up that way for quite a while with my old subs. With the new subs, while it does work for the 10db drop, I find that it blends better with the mains and sounds better with them set to small. 

After thinking about it some more, I also agree with raising the target level by 6db to match what the MMC-1 is doing. As stated, my fear was that I would lose SPL. I figure I may lose some SPL, but once I run the player, it should kick in the extra 4db to get me back to the levels I need. The plan now is to order a USB to MIDI cable so I can program the BFD. Then I will take some more measurements with REW and manually with the SPL meter and calibration disc to see where I stand. 

Thanks for the help.


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## Wayne A. Pflughaupt (Apr 13, 2006)

jlafrenz said:


> So My questions are first and foremost, am I correct in my thought process here? Do I need to set the target level to 85db so that the filters applied more accurately reflect what is happening in my system?


Absolutely not! There’s no good reason not to use the standard 75 dB Target when equalizing the sub. Any equalization it requires has no relevance or bearing on any level or gain adjustments that may be required after the fact. 

Regards,
Wayne


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## laser188139 (Sep 19, 2009)

Wayne A. Pflughaupt said:


> ... any level or gain adjustments that may be required after the fact. ...


I think, Wayne, the question arose because he has already adjusted the sub level before the fact, to address his player LFE issue. 

You're right, one could use the 75dB target to equalize, with the sub trims level, then after equalizing re-introduce the adjustments for the player's LFE problem. 

Another solution, I would think, would be to leave the target at 75dB and just lie to REW during the SPL calibration phase by saying the average SPL reading on the sub calibration tone is 75dB, irrespective of what the SPL meter reads. 

Have you ever used the Set Target Level option? I should have suggested it right away, but I wanted to understand why this problem arose. The Set Target Level option under the Target Settings seems designed for this situation, where one wants the target level to match the average SPL reading so that the equalization filters are not being generated to accomplish what is really a level adjustment. 

So many different methods to accomplish the same thing. 

Bill


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