Hi all
I recently built 2 sealed 150lts subwoofers with Dayton ultimax 18 inch drivers in each box.
Im using a Marantz 8805 processor and feeding the two LFE outputs to a Berhinger NX6000 power amp and then to each sealed subwoofer.
I used Audessey to set up the subwoofers and all the other speakers in my system, DIYSG HTM 12s at the front left centre and right.
The results i get measuring with a calibrated uMIK with REW are
and just the subwoofer
What do you think? Im unsure why there is a big increase in the subwoofer db ?
I set the levels manually and they are spot using UMIK 1 and REW also with a Radio shack SPL meter, matching the main speakers levels on my Marantz processor.
I used to have an Dspeaker antimode, if I bought another one would it be able to improve on my results?
I have the crossover set to 100 htz on the Marantz
Any views welcomed...thanks
I recently built 2 sealed 150lts subwoofers with Dayton ultimax 18 inch drivers in each box.
Im using a Marantz 8805 processor and feeding the two LFE outputs to a Berhinger NX6000 power amp and then to each sealed subwoofer.
I used Audessey to set up the subwoofers and all the other speakers in my system, DIYSG HTM 12s at the front left centre and right.
The results i get measuring with a calibrated uMIK with REW are
An externally hosted image should be here but it was not working when we last tested it.
and just the subwoofer
An externally hosted image should be here but it was not working when we last tested it.
What do you think? Im unsure why there is a big increase in the subwoofer db ?
I set the levels manually and they are spot using UMIK 1 and REW also with a Radio shack SPL meter, matching the main speakers levels on my Marantz processor.
I used to have an Dspeaker antimode, if I bought another one would it be able to improve on my results?
I have the crossover set to 100 htz on the Marantz
Any views welcomed...thanks
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Depending on room dims it looks like there's significant gain below 70Hz. The dip at 80 is going to be due to destructive interference at the mic position.
is the mic measurement an averaged response of different mic positions or a single position measurement. The null may dissapear.
Simplest remedy is positioning the subs asymmetrically in the room, which will create destructive interference at still other frequencies which may or may not be easier to deal with. Alternatively you can experiment with crossing the mains over at this frequency to see if their position handles that notch better.
is the mic measurement an averaged response of different mic positions or a single position measurement. The null may dissapear.
Simplest remedy is positioning the subs asymmetrically in the room, which will create destructive interference at still other frequencies which may or may not be easier to deal with. Alternatively you can experiment with crossing the mains over at this frequency to see if their position handles that notch better.
I would never design and set up my system anything like what you measure in post #1.
But after listening to my system for fine-tuning (and I have two quite fine subs), that rather resembles the curves I measure after tweaking by ear and quite a few years experience underlie my opinion.
Which sums up my views about wasted endless fussing over engineering perfection instead of ensuring you have the means of adjustment* after a human auditions the system.
BTW, that's pretty impressive output south of 35 Hz (although 1/12 smoothing would be a more conventional way to plot). Must sound good on organ music.
B.
*obviously that means a DSP unit
But after listening to my system for fine-tuning (and I have two quite fine subs), that rather resembles the curves I measure after tweaking by ear and quite a few years experience underlie my opinion.
Which sums up my views about wasted endless fussing over engineering perfection instead of ensuring you have the means of adjustment* after a human auditions the system.
BTW, that's pretty impressive output south of 35 Hz (although 1/12 smoothing would be a more conventional way to plot). Must sound good on organ music.
B.
*obviously that means a DSP unit
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Many thanks for the reply.
The room dimensions are 3mts x 6mts.
My subs are placed behind a acoustic projector screen and due to my room and size of them, i can not really move them. So its a matter of tweeking them where they are or adding an Dspeaker antimode and maybe let that tweek them more?
Would it do much to my original results ?
I dont understand why if the levels are correct in my av processor there is a 10 db increase in my subwoofer when using REW ?
The room dimensions are 3mts x 6mts.
My subs are placed behind a acoustic projector screen and due to my room and size of them, i can not really move them. So its a matter of tweeking them where they are or adding an Dspeaker antimode and maybe let that tweek them more?
Would it do much to my original results ?
I dont understand why if the levels are correct in my av processor there is a 10 db increase in my subwoofer when using REW ?
The mic measurement is from the MLP, I normally listening alone so I thought id measure where id sit?
So what would an Dspeaker antimode do to those results?
So what would an Dspeaker antimode do to those results?
Have you tried different crossover frequencies? How about manually lowering the sub level?
What do you think of the sound? Did you have the same opinion before you measured?
I would say you have a fair amount of tweaking to do before you need an additional processor.
What do you think of the sound? Did you have the same opinion before you measured?
I would say you have a fair amount of tweaking to do before you need an additional processor.
I did manually lower the sub but dont understand if you use the test tone built into the processor the output is too low compared to the mainspeakers ? But then it measure ok in REW ?
I will measure it tomorrow with different crossover frequencies set in the processor. See how the main speakers handle a 80 htz instead of the subwoofer?
I was just thinking about the increase in volume level in my subwoofer compared to the main speakers. What if the test tone for level matching from the processor emits was a 75htz test tone? So I would be level matching with a test tone frequency in the large dip, hence the large increase? Not sure what frequency sub test tone are?
Will somebody please tell us how it sounds....
That plot rather resembles the curves I measure after critical fine-tuning by ear (AKA "house curve"). Wrong-headed to continue to say the plot is wrong if the sound is good.
B.
That plot rather resembles the curves I measure after critical fine-tuning by ear (AKA "house curve"). Wrong-headed to continue to say the plot is wrong if the sound is good.
B.
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It sounds fine but then if I'm missing certain frequencies I would not be able to tell by ear? Hence measuring it and seeing the dip at 75 htz.
What would an Antimode do to those results? Improve them? To spend £300 on a antimode s or £700 on a duel core antimode I'd want to see vast improvements.
The results don't look to bad to me?
What would an Antimode do to those results? Improve them? To spend £300 on a antimode s or £700 on a duel core antimode I'd want to see vast improvements.
The results don't look to bad to me?
if you like the way it sounds thats good. I would play around with level, placement, eq etc, but it looks ok, really depends on what you're listening to. For hip hop or electronic music I often turn up the subs, for some jazz and small ensemble classical I may turn them off. Sharp narrow dips are hard to hear, you're probably not missing much.
Thanks i will have a play about, it's mainly for rock / indie music so drums and bass and it's part of a av system so movies too.
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