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That makes sense. So to recap PEQs on output of HF and LF till you set delay then take a combined sweep (with delay) and apply REW's EQ to the input side. Correct? Now more questions I'm on the fence between two delay numbers based on Spectrogram/GD I see merits in both (I think) and they are quite a bit apart in time. Would it be better to have the vertical line closer to zero but it dropping off at a higher point or have it slightly to the right of zero but further down the spectrum? I'll post Spectrogram and GD for both. First the spectrograms so you can visually line them up. First one is 2.0ms (1.9 was very close) it has a more vertical zero line till it drops off. Second is 2.4ms It has the energy line slightly more right of zero but further down and it has a part that comes back around 400 till dropping off. The ones between 2.0 and 2.4 were visually "worse" than these two. Now the Group delays for those same two above 2.0 first then 2.4. To me 2.4 seems better because visually there seems to be more closer to zero (the 800 stuff)...but on the 2.0 there is a lot more in one chunk near zero 400-650.

I ran lots of sweeps with various delays in tiny increments/decrements and think I have a better Spectrogram and Group Delay. Maybe not a sweet spot but better spot, as in a "not so bitter spot". I have some questions on this second round of PEQs. Since I only put delay on the HF do I run a HF only sweep and optimize with REW Wizard; or do I run a full (HF/LF combined) sweep? No matter the answer above I'll get say 4 to 6 new PEQ values. Surely they won't be anywhere near the existing ones I started with. How do I apply the new values? Do I simply combine them to the existing PEQs going from say 4 to 8 Do I try and find ones that are close to each other in Hz value and +/- dB value and combine them Do I replace my existing ones with only the new ones - I don't think so since the new ones are based in the existing ones If the answer is simply add them so you end up with more, what happens if I run out of PEQs? Do I need to make a best guess on winners and losers?

That helps a lot, thanks! I thought we were looking for the differences between the two lines at a given point (the XO point most likely). Knowing the goal in a perfect speaker would be a horizontal white makes sense. Zero on the graph, zero all across, no delay anywhere. Now I get it. Again, very helpful to know the goal. In an earlier post in one of these threads I asked if a perfect speaker would have a vertical line at zero, I don't believe anyone ever answered that question. Making me think now that Chris is the only one that would actually know that answer. My take away was that we didn't need it vertically at zero we just wanted smooth transitions moving to the right, not jagged. Obviously that was the wrong conclusion. Learning more every day, thanks. I'm getting the feeling that not many here actually know what they are doing, but are not as willing as me to admit they don't know how to use these tools or "why" behind what the changes do. That is fine, I personally just like to understand the why and know what I am actually doing, not just blindly follow instructions. This is very much the case for me. I don't really have any sort of background to understand what I am looking at. I'm pretty methodical and pretty good at following directions. I just need to know WHAT the goal is and how to implement the changes and I'll be on it like a dog on a bone. So far it has been a lot of trial and error and shooting in the dark.

Now I'm stumped. I thought on the Spectrogram you looked for the sharp change in direction on the Peak Energy curve near the XO point. That would make me think about 1.5ms (first blue line) or perhaps ~3.6ms (2nd blue line). How do I read below and come up with 2-2.5ms (the range of the two black lines). As for the Group Delay, I'm still dumb as a rock missing the basic concept. I zoomed in on where I think the issue should be. Are we looking for the difference between red and white lines where they depart? If so moving from left to right which orange circle shows us the roughly 2ms issue? 150-700 seems like the problem to me you say "nearly flat" so I am obviously not getting it. I thought the closer the white line (excess) tracked to the sweep (red line) the better because there was no gap/delay between them.

Now the group delays for those same sweeps/Spectrograms above 600/800/1000. To my eyes I say 600 and 1000 are decent. Looks like only need to figure and apply the delay of around 5ms occurring around those two 300Hz humps. What is the funky stuff happening on the 800 sweep between 150 and 600? Curious to hear what others think for both Spectrograms and Group Delays. Again no delay on any just moved my XO from 350 earlier this morning to 600/800/1000

Here are the 3 Spectrograms for the sweeps above. Note that on my 350XO point on the previous page they are not "smooth" before applying any delay. That is none of these have delay yet. Just full sweeps with various crossover points all Bessel 6db. They look more like what Chris and others have posted in the past. They also look a lot alike.

So here is the measurements at 600, 800 and 1000. Nothing too earth shattering I can see. I think the Spectrograms/Group Delays are much more interesting for discussion. I'll post them in different posts so we can comment individually on what each means NOTE Red = 800 not 8000

No really next page

See Next page

I'm stopping where I am and refocusing my efforts on that. Nothing has changed since this morning's measurements. I'm simply going to keep the EQ REW supplied me and move the XO around to 600, 800, 1000 (keeping 6dB, Bessel) and then see what my Spectrograms and GDs say. What I'm struggling with conceptionally is....I thought the point of a 2-way system was to have the majority of the "work" done by the HF section be that the 402 horn and drive in a Jubilee set up or most others. While the LF just fills in the bottom end. It is the midrange we all love with horns, right? Don't most people cross a 2-way Jubilee around 400? And you only have a 2" driver. I've got 8" drivers. Obviously I'm missing a key point or two. Please advise. Thanks to all for all the help so far!!!

@Chris A Two questions 1 in the above Group Delay plot how did you get two sets of measurements? I can see how to Generate minimum phase and turn on/off the Excess group delay, but I can't seem to put two sweeps on the same screen for group delay like I can for "All SPL" 2 What is the flaw(s) in my thinking process below? Started from scratch today, again, with single HF/LF 2-way in the center of the room (away from walls) with padding on walls/floor. Next step will be to move outside if necessary. No PEQs, No delays, No XO points Measure and flatten HF only with EQ wizard Measure and flatten LF only with EQ wizard Level gain between HF and LF based on individual measurements, SPL meter and ear Set crossover points for HF and LF along with crossover type and slope Take combined measurement of HF/LF, with High and Low pass crossover points and slopes all in place This is what the measurement looks like for that last step with both the HF and LF set to a 350Hz crossover point and Bessel 6dB (I've got plans to bring down that 400-800 but sticking with EQ wizard settings for now). Also guessing that 400-800 range is in part due to 350 XO. Next I produced and look at the Spectrogram, it actually looked pretty decent (I think) without any delays. Am I correct that since peak energy is not jagged not too bad? Next I generated the Excess Group Delay in the Group Delay window. Still not sure how to read it beyond the "gaps" between plot around XO point. I think I have an issue around 300Hz of about 3.5ms, is that correct? See cursor at 302Hz showing 18.58ms (orange) and ~22 (white). Is that an issue? If so since at/near XO point how do I know if it the HF or LF that is the offending driver? Am I wrong about the issue at 302Hz and it is somewhere in the 115-250Hz region below? I've got measurements with Spectrogram and Group Delay for both a 3.5ms delay on the HF and a 3.5ms delay on the LF since I can't seem to get it in my thick skull how to tell where the problem is on the GD screen and the Spectrogram does not have an obvious jagged like in previous posts. But I'll hold off posting my pictures of various graphs with delay set till we get some answers on the above. I'm hoping my though process and Chris' comments will help others in particular @Ziggurat

Red = 200 crossover Blue = 350 crossover Green = 450 crossover Which one are you saying 8ms and around what frequency? As for the green one the XO point is 450 but the Group Delay looks pretty good (to me) there. It is back around 182Hz that I can put the cursor on and see/read the following differences 42.3 - 36.8 = 5.5ms. But again to me...and I know nothing, it looks pretty good around 450. It is a 6dB Bessel, so 1st order with lots of overlap, right? If I were to account for the 5ms delay around 182 wouldn't that, perhaps, produce more group delay in other areas like 200-600 which seems pretty good?

So are these next two statements for two different crossover points correct.... In the Green/White graph there is not much group delay around the 450 crossover point? Should I apply any delay, maybe because of the 182 difference? In the Blue/White Graph there is aprox 3ms around 280Hz and/or 6ms around 184Hz with the 350 crossover point If you were to go by the Red, Green, Blue group delay plots alone and no listening would you pick the 450 crossover point since it appears to not need any correcting?

How is this read? On my marked up version below is it the red circles where the Excess Group Delay (white line) goes from horizontal at zero to where to goes vertical or is it the aqua circles where the white and blue lines don't track evenly or possibly something else? What does a trace look like when the proper delay is applied. Without having a Spectrogram to fist look at how is below read? Meaning what is the delay and is it applied to the HF or LF in a 2-way system?

Not taking that way, either.