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Discussion Starter #1 (Edited)
Here is my frequency response in REW (note that the sub is off. These are separate L-R readings. The tweeters are on an active crossover @ 3.5kHz)


See how the 100-300Hz range for the midrange speakers is much lower than the 400Hz-3.5kHz range? So that makes me wonder, when EQing, do I boost the lower range, or cut all of that upper range down? Originally I had my target curve set here:


And through EQing cut the 400-3500Hz range down to match the 100-400Hz range. But I could also place the target curve more at the average:


The response that I got after EQing is not that bad:


But I'm just wondering how more-experienced people would go about it-- where they would set the target curve at before EQing, and why. It doesn't seem good to cut as much as I'm cutting, but I know boosting isn't very favorable either...

Also, don't worry about the fact that the tweeter range is much lower than the curve in the second EQ example. I lowered their overall level in order to be closer to the first target curve example before EQing... if I were to raise the target curve, I would raise the level of the tweeters accordingly, and re-measure, so that they're closer to the target curve pre-EQing... don't worry about that range haha.
 

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Most of the time it’s best to lower a frequency so you can achieve lower distortion


Sent from my iPhone using Tapatalk
 

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You pictures aren't working... While cuts are preferred, you have to be careful that you don't cut too much or you will run out of volume. It's a balancing act - but as stated above, boosts can cause distortion, so you want to lean towards cutting over boosting most of the time.
 

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You pictures aren't working... While cuts are preferred, you have to be careful that you don't cut too much or you will run out of volume. It's a balancing act - but as stated above, boosts can cause distortion, so you want to lean towards cutting over boosting most of the time.
Can you expound as to what causes the distortion?
 

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Can you expound as to what causes the distortion?
Are you suggesting that too much boost cannot lead to clipping (which is a form of distortion)? Wouldn't you agree that when EQ'ing to a target curve, that you are better EQ'ing to a level where you are using cuts to knock down peaks as opposed to using boost to fill "valleys"?

See, I can post silly questions too... Instead of asking these silly questions that you already know the answers to, why don't you just "enlighten" us with your awesome knowledge instead? Why do you play these little "let me ask a question that I already know the answer to in order to try and belittle someone that is trying to help someone else" games? I've noticed that you like to try and belittle people instead of just helping the person that is asking for help in the first place. Very big of you...
 

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Are you suggesting that too much boost cannot lead to clipping (which is a form of distortion)? Wouldn't you agree that when EQ'ing to a target curve, that you are better EQ'ing to a level where you are using cuts to knock down peaks as opposed to using boost to fill "valleys"?

See, I can post silly questions too... Instead of asking these silly questions that you already know the answers to, why don't you just "enlighten" us with your awesome knowledge instead? Why do you play these little "let me ask a question that I already know the answer to in order to try and belittle someone that is trying to help someone else" games? I've noticed that you like to try and belittle people instead of just helping the person that is asking for help in the first place. Very big of you...
It is not a silly question if people do not know why or how it creates distortion.

It is your premise, which I agree with... so it your enlightenment to share.

You pretty much have the bases loaded, so just home run it in.
Explaining the reasoning behind the dogma helps everyone, and it is better coming from you than me.

Since you are giving me constructive advice, then maybe suggest a few examples of belittling for me to look at, and I can work on it.

Obviously your post left nothing in it belittle.
This is not about me belittling anyone... it is about us helping the OP.
[edit] SubterFuse batted it in for you.
 

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I don't see any pictures of your measurements, and can't comment on that.


The general rule of thumb is that cutting EQ is safer than boosting.

Does that mean we should NEVER use EQ boosts? No.

Using EQ boost is safe as long as the cumulative effects of the EQ filters does not drive the signal into digital clipping.

How do we know how much that is? This is where the answer becomes harder to define because it depends on the equipment. For example, Helix processors are designed with 5 dB of channel gain boost available above the 0 dB mark. That means the factory default settings on the Helix processors is not Unity Gain. It is 5 dB below Unity. So the designers are giving us some headroom to work with.

Some processors like the Helix give us a graphical representation of the EQ filters and their effect on the electrical signal. That chart usually begins as a flat line and then as we apply filters the flat line will bend up or down. If we know that the Helix has 5 dB of headroom above the 0 dB line, and we do not increase the channel output gains, then in theory we should have up to 5 dB of headroom for EQ boosts. So our goal would be to make sure that none of our EQ causes the line representing that channel's signal does not ever go above +5 dB. As long as this is true, then we know that the device is not clipping the signal.

If we have an area where the signal level has been reduced, like outside a crossover region, then we can actually boost a lot there because the overall level of the signal has been cut significantly by the crossover filter, leaving us even more headroom.




In addition to the graphical chart of the EQ, each channel on the Helix has an Output meter with clipping detection. Playing a test tone and watching that clipping indicator is also a good test to make sure there is no clipping. This can be done with the RCA cables disconnected from the amps if you are concerned about playing test tones on your speakers. It's an electrical test of the signal in the DSP, so there is no need to play the tones on the amps or speakers for this kind of test.

But, going back to the general rule of thumb, if we can fix a problem area by cutting peaks rather than boosting dips that is safer.

If we cut too much with EQ, then it is possible that the overall voltage coming out of the DSP will be low and that can result in reduced volume output from our amplifiers. This is where amplifier gains come into play, because they are used to adapt the amplifier to the range of voltage which it will be seeing from the DSP. If we set amp gains first and then tune the DSP with a bunch of EQ cuts, then it will be a good idea to revisit the amplifier gains afterward and make sure they are optimized for the voltage coming out of the DSP.
 

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Discussion Starter #8
I have no idea why the pictures are not working. I'm too new to be allowed to post links. Here is the imgur URL though:
imgur.com/a/WFZlJlo

with 1) my L and R sweeps, 2&3) possibilities of where i could put the target curve, and 4) my sweeps after EQing to the lower target curve

Yeah, having widely cut the 400-3500 Hz frequency range to reach the level of the 100-300 Hz range (about 5 dB lower) definitely reduced my overall volume by a ton, I now have to have my iPhone volume all the way up at times (granted, I do like it loud). If cutting is the overall consensus, I would definitely boost the gain on my amp just to make up for this.

I'm using a Dayton Audio DSP-408 (yeah I know, not $400 top of the line DSP here).

I guess I'm also wondering, is it WORTH IT to have that 100-300Hz frequency range match the rest, if it means cutting those higher frequencies?
 

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OK so for this situation, I would start by using a low Q (maybe .8 or 1.0 Q) cut filter centered about 1000-1100 Hz. That would bring a lot of that midrange down to your target with only a single filter.





You can actually simulate this in REW using the EQ section. Or, you can even use the EQ section to create filters for you automatically and then try them out in your DSP.
 
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