Im sure this is redundant
But while fine tuning , I did some more research on test tones and their effect on tuning

Ever wonder what they mean when we use a 1000Khz test tone to set gains?
Well some recommend a -5 db test tone for some over lap
Great idea
I will try to embellish some more
The standard Test tone is set @ 0db
So whats that mean to me and my new amp or better yet my new speaks
Well an analysis of the tone looks like this
I have broken down the conman test tones @ 1000 hz that we all use to set up gains on an amp.
The main tones are 1000hz @ 0db/-2.5db/-5.0db/-7.5db/-10db
This snap shot from Mp3Gain shows the volume level of each tone.



So you can see that using lets say the -7.5 tone I have highlighted will produce a volume level of 95.6.
This is great if you have all of your music set at around 96
Where you could get into trouble is if you use the -10 tone with your music set at 96.
Its easy with Mp3Gain to evaluate the test tone you want to use when setting up your amp
I also looked at 2 sources
#1 USB with MP3 files
#2 Bluetooth from my phone with a music player
There can be subtle differences from source to source
Maybe enough to cause the magic smoke to appear.
Here are actual VAC readings with different test tones used from my ARC 600.4, test tone ran with volume on the deck set to 35 (MAXED OUT) NO Filters and set Flat on EQ. All MP3 On a USB
I never adjusted the Gain once set, the only difference is the level of the test tone

Tone #1 1000Hz @ 0Db



Tone #2 1000Hz @ -2.5Db



Tone #3 1000Hz @ -5Db



Tone #4 1000HZ @ -7.5Db




Tone #5 1000Hz @ -10Db



So translate the VAC to power
0Db Tone = 275 Watts @4 Ohms
-2.5Db Tone = 250 Watts @4 Ohms
-5.0Db Tone = 190 Watts @4 Ohms
-7.5Db Tone = 125 Watts @4 Ohms
-10Db Tone = 50 Watts @4 Ohms
These numbers are not exact, I didnt take the time to do the math, But they are close enough that you can see the real difference
So for me
The -5 Db test tone in this instance has me running @ 190Watts.
But my music is all set for 91Db Volume level , thats lower then the 98Db volume level of the -5Db test tone
So unless I have a song running a volume level above the 91Db, I should never hit the ceiling. Thus the Headroom or Overlap
Set the amp up with the -10Db test tone, Well your just really losing efficiency in my opinion.
So what should a guy take from this
#1 know what your music and source are putting out for volume level
#2 Pick a test tone that comes close to your Music level.Leave a little headroom.
#3 Volume level all of your music.

Hope this isnt to confusing.

 

Thanks for bringing this in. I 've being thinking about this for a while.
In your case seems like you have plenty of power to spare on the amp.
But what if you have a 4 channel amp rated at 150W RMS @ 4 Ohms and you need to use the 4 channels to feed 4 speakers rated at 100 W RMS like in my case with the 4 6900s?
Do we know what level does MP3Gain uses for the gain adjustment?
Is it the peak level, the average level nor some other level?

 

Here is my concern
All my music is at 94db. They way I handle it is like this. I check the level with MP3 Gain, then do the gain adjustments and other manipulation like EQ, editing of the begining and end of the track, to avoid gaps between songs, etc. on Audacity. Then bring it back to MP3 Gain to check the level.
Unfortunately Audacity being such a powerfull program doesn't have a way to display the actual gain and there are some discrepancies between MP3 Gain and Audacity regarding clipping. Tracks that show clipping on MP3 Gain doesn't show it in Audacity. In the other hand if there is not clipping in Audacity there is not clipping in MP3Gain for sure.
Now I have the music at 94db. Now lets say that I adjusted the gains at 98 which is -5 db, but my music is 4db below that level, so how much power going to my speakers I'm loosing? A lot.
If I had two 4 channel amps bridge at 300W RMS @ 4 Ohms, then it might not be a problem.
The way I see it and I might be wrong, is that the new 94 db level is now like the original 0db level. If you take the time to process all of them to this level.
Now if you try to play something that is above this level then you are in serious trouble.
So, if 94db is now the maximum unclipped level you could adjust the gains at a lower level, lets say at 89db which is -5db and get some more power to your system.
In my particular case I haven't done it, however I have my system adjusted at 93db and my music is at 94 and it is super clean, not signs of distortion whatsoever.
When I had the system adjusted like you explain above I was leaving to much power on the table. Again I might be totally wrong on this, but my system now is louder than it was before and still free of distortion.
So I found that at 94 db all my music is prety much free of clipping

 

94 is a good baseline. My music seemed to fallin around 91Db without clipping
Most digital media is more robust then the earlier days, so there are some that dont feel the clipping is a big issue

I actualy have my music set @96Db on one stick. But as you pointed out MP3Gain showed a lot of clipping at that level.
Ill be experimenting more today. With both the 91Db and the 96Db levels
In all honesty I was like you in the beginning, I set the Gain @150Watts but the system seemed to be lacking, as you stated I left too much on the table with the higher rated test tone.
In all honesty
Today I am taking the 0Db test tone and making it 91Db volume level with Mp3Gain
Then ill compare the output to the -10Db tone and see what the difference is
Perhaps setting the test tone to the targeted MP3Gain Volume of the music is the best way to get the system dialed in.
Ill know more , or have a better idea tonight..
Also
The test here was to really show the difference in level into the amp
@0Db the amp was running 275, This amp isnt rated for that, So how damaging is that?
Granted all of the music would need to be set @102Db for that to happen.
But I do have a few songs that are @ 102Db before I cleaned them down to 91Db
So the major take away should be .
Know what level you are putting into the system. That will help not seeing the Magic Smoke @80Mph some day

Oh and this is from the Mp3Gain site.

"MP3Gain does not just do peak normalization, as many normalizers do. Instead, it does some statistical analysis to determine how loud the file actually sounds to the human ear."

Take it for what its worth

 

What HU do you have?
Mime is the Kenwood 998.
I also set the gain at 35 which is the maximum volume on this unit.
I can tell you that the wattage drop from 35 (150 W) to 34 is brutal. If my memory serves correctly is like 97 Watts at 34.
However this change of level doesn't translate in a huge drop of perceived volume.
if you have a chance test for this too and report back.

 

Hmmmm That Kenwood 998 gain should be set at 26-27 volume. 35 is MAX on that unit.

 

Just got back from a 1750 mile trip
2 week old 998 kept having the screen freeze
So I pulled it and installed a Kenwood KMRM318BT (Thus all of the testing im trying out)
It seems to have all of the features I want compared to the 998.

But Ill look at power drop when I turn the Head unit down
Ill do the 1 clickdown to 94 for you
Also ill look at the drop the HU set @ 80% of max (30)
I know a lot of folks tune their system that way.
I like running the HU @ Full Open and adjusting from there
For me less margine of error if it AVC to full volume @80MPH

 

I don't buy setting the gain at 3/4 of max volume. If you do that, you are going to be blowing speakers if you go volume happy

 

Roger that.

 

You are correct
No pics but here are my tests results
92Db volume level test tone
HU Volume = 35 Gain set @ 24.42 Volts AC = 150 Watts
HU Volume = 34 Gain set @ 21.95 Volts AC = 122 Watts
HU Volume = 30 Gain set @ 08.65 Volts AC = less than 10 Watts?

Interesting .
I also ran the tests with the USB set @ 96Db and the gains turned down
My old 59 Year old ears seemed to like the 91Db settings better
Ill know more when my son (he has good ears) comes over
Ill run both setups against his ears
The only advantage I see with the 96Db setting, is the gain turned down on the amp.
Wish I had an analyzer, I would like to see the difference in the noise floor at both settings. That may be the only advantage to the 96, lower noise floor on playback. But ny ears didnt hear that