Freq Responses graph

[ciotime]

Found another old graph plotted in 2017, when I was using


So the red one is the one with the cuts/boost entered via Rat? If it is, then you already have a house curve but I would apply a cut of about 2 to 3 dB as follow:

20 Hz: -1.5
23 Hz: -1.7
25 Hz: - 1.8
31 Hz: -1.7
35 Hz: -1.9

and you are done with the sub and ready to do the FL and FR.

You can definitely fix the two sharp dips at about 140 and 155 hz but you would have to take deeper cuts to the 20 to 115 Hz range. In other words, lower the target spl to about 78 dB. Without that, you can still reduce those tow dips by 2 to 3 dB but likely not more than that. Your call..

"So the red one is the one with the cuts/boost entered via Rat?"-yes

So the cuts will be added to the Subs right on top of the previous ones?

"and you are done with the sub and ready to do the FL and FR."-sorry for the noob question but how? add the same cuts/boosts as I did on the subs?

"You can definitely fix the two sharp dips at about 140 and 155 hz but you would have to take deeper cuts to the 20 to 115 Hz range. In other words, lower the target spl to about 78 dB. "-Yes I do wanna try and see if I can improve the dips at 140 and 155hz. So since our previous target was 80dB I just add a 2dB CUT on ALL the previous figures? And do this for the FL/FR and Subs?

 

[PENG]

So the cuts will be added to the Subs right on top of the previous ones?

You can do that but it would be clumsy and complicated. It is better to open the last Rat file and modify the data entry table.

So the new table will look like this:

Freq. anchor points	SPL at anchor freq. points	dB to cuts/boosts	Change to
17	80	2.5
20	80.5	2	0.3
23	81	2	0.3
25.6	83	-0.5	-2
30	84	-1	-2.5
34	83.5	-1	-2.8
37	84	-2
40	84	-2
45	84	-2.5
50	83.8	-2.5
54.5	84	-2.5
62	83.8	-3
67	84.8	-4
70	84	-3.5
80	83	-0.5
84	84	-3.5
86.5	84	-4
89	85	-4.5
90	84.5	-4.5
93.5	84.5	-4.5
94	84.5	-4.5
98	84	-4
100	83.5	-3.5
107	83	-3
109	82.3	-2.3
128	81	-1

After that, the REW graph should look flatter, the house curve (increasing towards 20 Hz) will still be there but less severe, that is a gentler slope.

It really is looking good, keep in mind if you apply 1/12 smoothing that a lot of people do, it will of course look even better.

 

[PENG]

And don't forget to save the modified file with a new name, again copy it to the device (tablet/smart phone), open it to check that the new curve looks right before sending it.

 

[ciotime]

You can do that but it would be clumsy and complicated. It is better to open the last Rat file and modify the data entry table.

So the new table will look like this:

Freq. anchor points	SPL at anchor freq. points	dB to cuts/boosts	Change to
17	80	2.5
20	80.5	2	0.3
23	81	2	0.3
25.6	83	-0.5	-2
30	84	-1	-2.5
34	83.5	-1	-2.8
37	84	-2
40	84	-2
45	84	-2.5
50	83.8	-2.5
54.5	84	-2.5
62	83.8	-3
67	84.8	-4
70	84	-3.5
80	83	-0.5
84	84	-3.5
86.5	84	-4
89	85	-4.5
90	84.5	-4.5
93.5	84.5	-4.5
94	84.5	-4.5
98	84	-4
100	83.5	-3.5
107	83	-3
109	82.3	-2.3
128	81	-1

After that, the REW graph should look flatter, the house curve (increasing towards 20 Hz) will still be there but less severe, that is a gentler slope.

It really is looking good, keep in mind if you apply 1/12 smoothing that a lot of people do, it will of course look even better.

Thanks again...so what do I enter into the FL/FR? The same numbers I did for the subs? Do I do the same for the Center as well?

 

[PENG]

Thanks again...so what do I enter into the FL/FR? The same numbers I did for the subs? Do I do the same for the Center as well?

So you are ready to have more fun?
From your reference curve, your can definitely do something about the peaks at about 115, 150, 165, 220, 280 and between 350 and 400 Hz.

The problem is, I wouldn't want to suggest a data entry table as yet without seeing the accurate frequency points as I can't just scale it from the captured graph due to the log scale. So you would have to identity those anchor points for me from your source REW graphs.

Also, to do a better job, you should look at the FL and FR graphs separately as unlike the 3 subwoofers, the FL and FR are discrete channels.

The not too sharp dips at about 140 and 155 Hz could likely be improved slightly but you won't be able to do much about those at 240 and 320 Hz. I suspect most would have such sharp dips here and there and according to experts those wouldn't be noticeable (audibly) anyway.

 

[PENG]

To me, what you have now is more than good enough. Trying to improve on the 120 to 400 Hz may be a good exercise but I doubt it would make much audible difference.

Did you use the minidsp to EQ that range too?

 

[ciotime]

So you are ready to have more fun?
From your reference curve, your can definitely do something about the peaks at about 115, 150, 165, 220, 280 and between 350 and 400 Hz.

The problem is, I wouldn't want to suggest a data entry table as yet without seeing the accurate frequency points as I can't just scale it from the captured graph due to the log scale. So you would have to identity those anchor points for me from your source REW graphs.

Also, to do a better job, you should look at the FL and FR graphs separately as unlike the 3 subwoofers, the FL and FR are discrete channels.

The not too sharp dips at about 140 and 155 Hz could likely be improved slightly but you won't be able to do much about those at 240 and 320 Hz. I suspect most would have such sharp dips here and there and according to experts those wouldn't be noticeable (audibly) anyway.

View attachment 49284

"So you are ready to have more fun? "-sure!!!

"So you would have to identity those anchor points for me from your source REW graphs."-you want me to post a more detailed graph of these points? A close-up view?

"Also, to do a better job, you should look at the FL and FR graphs separately "-so take a FR via REW of the FL only and FR only?

"The not too sharp dips at about 140 and 155 Hz could likely be improved slightly but you won't be able to do much about those at 240 and 320 Hz. I suspect most would have such sharp dips here and there and according to experts those wouldn't be noticeable (audibly) anyway."-Totally fine...sharp dips are NOT audible anyway correct?

 

[ciotime]

To me, what you have now is more than good enough. Trying to improve on the 120 to 400 Hz may be a good exercise but I doubt it would make much audible difference.

Did you use the minidsp to EQ that range too?

"Did you use the minidsp to EQ that range too?"-Nope...the EQ done via the miniDsp was limited to only about 120hz

"To me, what you have now is more than good enough. Trying to improve on the 120 to 400 Hz may be a good exercise but I doubt it would make much audible difference."-Well if it's good enough for you then I'm fine with that. Maybe I can just improve the 140hz-160hz area then I'm good.

 

[ciotime]

 

[PENG]

View attachment 49285

Just a quick trial, not an accurate way to do it, would be the following:

112 Hz..................... -1
125 Hz..................... +0.5
128 Hz..................... +1
133 Hz....................... +1.5
135 Hz....................... +1.7
137 Hz....................... +2
140 Hz....................... +2.3
175 Hz....................... -2
195 Hz....................... -2
210 Hz...................... +2

Do it to both FL and FR and call it a day.

You can do a lot more (first a detailed analysis and then calculate the cuts) to flatten the range, but imo there is no need to spend so much time if the results are not going to be all that audible in the end.

 

[PENG]

Now that I have seen enough, I am very confident that you can achieve +/- 1.5 dB or better for the range 20 to 130 Hz; and even to 200 Hz but in that scenario with a couple of narrow dips. That would be with or without the use of the minidsp.

Reality is that you would have to spend hours on it to analysis results, calculate and multiple trial runs. For all intents and purposes, what you have now is very good, better than most I have seen. You obviously are very good at this..

 

[ciotime]

Just a quick trial, not an accurate way to do it, would be the following:

112 Hz..................... -1
125 Hz..................... +0.5
128 Hz..................... +1
133 Hz....................... +1.5
135 Hz....................... +1.7
137 Hz....................... +2
140 Hz....................... +2.3
175 Hz....................... -2
195 Hz....................... -2
210 Hz...................... +2

Do it to both FL and FR and call it a day.

You can do a lot more (first a detailed analysis and then calculate the cuts) to flatten the range, but imo there is no need to spend so much time if the results are not going to be all that audible in the end.

So to recap the above figures are for the FL and FR ONLY...not for the Subs right? And none for the Center as well?

Also do I also need to enter the figures we used for the subs into the FL and FR as well? Or just the figures above?

 

[ciotime]

Now that I have seen enough, I am very confident that you can achieve +/- 1.5 dB or better for the range 20 to 130 Hz; and even to 200 Hz but in that scenario with a couple of narrow dips. That would be with or without the use of the minidsp.

Reality is that you would have to spend hours on it to analysis results, calculate and multiple trial runs. For all intents and purposes, what you have now is very good, better than most I have seen. You obviously are very good at this..

"For all intents and purposes, what you have now is very good, better than most I have seen. You obviously are very good at this.."- Thanks Peng...I'm learning as I go along. Even though I've been an HT enthusiast for about 15 years now I'm still trying to learn new things. All thanks to people like you who go out of their way to help. Truly thankful. Will post the new graphs once everything's setup. Gotta go to bed for now. It's 130AM right now here in the Philippines.

 

[PENG]

"For all intents and purposes, what you have now is very good, better than most I have seen. You obviously are very good at this.."- Thanks Peng...I'm learning as I go along. Even though I've been an HT enthusiast for about 15 years now I'm still trying to learn new things. All thanks to people like you who go out of their way to help. Truly thankful. Will post the new graphs once everything's setup. Gotta go to bed for now. It's 130AM right now here in the Philippines.

Wow, 1:30 am! You're truly an enthusiast, as crazier as I am..

 

[ciotime]

Wow, 1:30 am! You're truly an enthusiast, as crazier as I am..

Hahaha...I'm actually more of a night person. I have more energy during evenings. Just have to sleep coz of work but on weekends I go to bed at around 3AM

Anyway just to clarify the last figures you suggested are for the FL and FR ONLY...or do I need to input the new data into the Subs also? And no adjustments for the Center?

Also do I also need to enter the figures we used for the subs into the FL and FR as well?

 

[PENG]

Hahaha...I'm actually more of a night person. I have more energy during evenings. Just have to sleep coz of work but on weekends I go to bed at around 3AM

Anyway just to clarify the last figures you suggested are for the FL and FR ONLY...or do I need to input the new data into the Subs also? And no adjustments for the Center?

Also do I also need to enter the figures we used for the subs into the FL and FR as well?

Just enter those values to the FL and FR channels for this round. We don't know how they would interact with the subs so let's see the results first and go from there. Chances are good there you may have to do something to the sub channel too in the below 140 Hz range, hopefully not..

 

[PENG]

Just enter those values to the FL and FR channels for this round. We don't know how they would interact with the subs so let's see the results first and go from there. Chances are good there you may have to do something to the sub channel too in the below 140 Hz range, hopefully not..

When you are done, in additional to the unsmoothed graphs for further tweaking if you wish, please also post one with 1/12 smoothing so as to compare with other member's.

 

[ciotime]

When you are done, in additional to the unsmoothed graphs for further tweaking if you wish, please also post one with 1/12 smoothing so as to compare with other member's.

Just took a new set of measurement's using the data you provided for the FL and FR along with the subs across a 3 seat sofa. 2 graphs one without any smoothing and one with 1/12th smoothing. L+R was used as well.

 

[PENG]

Just took a new set of measurement's using the data you provided for the FL and FR along with the subs across a 3 seat sofa. 2 graphs one without any smoothing and one with 1/12th smoothing. L+R was used as well.

View attachment 49309View attachment 49310

Looks pretty good! So now you get the idea and if you want to do more it is up to you. If you feel the bass is too hot now, then the easiest way to ease that off is to adjust the level trim "subs 1+2 and lower it by 2-3 dB and you should be home free.

I assume the red one is the mlp. I expect to see more improvement to the dips in the 120 to 170 Hz range. Please check your boosts entries to the frequency anchor points I gave you, that is:

133 Hz....................... +1.5
135 Hz....................... +1.7
137 Hz....................... +2
140 Hz....................... +2.3

If those were correct then you may as well remove those boosts and apply the same to the subwoofer channel and see what happens.

Also, in additional to applying those boosts above the the sub channel (using Ratbuddyussey obviously), reduce the level trims to both sub 1 and sub 2 by 2 dB, but do that last, that is after you finish editing with Rat and send the file to the AVR. Then ran REW again and this time I am quite sure you will see some further improvements.

 

[ciotime]

Looks pretty good! So now you get the idea and if you want to do more it is up to you. If you feel the bass is too hot now, then the easiest way to ease that off is to adjust the level trim "subs 1+2 and lower it by 2-3 dB and you should be home free.

I assume the red one is the mlp. I expect to see more improvement to the dips in the 120 to 170 Hz range. Please check your boosts entries to the frequency anchor points I gave you, that is:

133 Hz....................... +1.5
135 Hz....................... +1.7
137 Hz....................... +2
140 Hz....................... +2.3

If those were correct then you may as well remove those boosts and apply the same to the subwoofer channel and see what happens.

Also, in additional to applying those boosts above the the sub channel (using Ratbuddyussey obviously), reduce the level trims to both sub 1 and sub 2 by 2 dB, but do that last, that is after you finish editing with Rat and send the file to the AVR. Then ran REW again and this time I am quite sure you will see some further improvements.

"If those were correct then you may as well remove those boosts and apply the same to the subwoofer channel and see what happens."-After doing this I just took a REW measurement. MLP graph is with NO smoothing while the graph across the 3 seats are 1/12th smoothing.