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Drastically diminished subwoofer performance, cant figure out why, please help

bomt697

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Hello,

I recently upgrade my HT setup and moved my old equipment into a computer / game room.
After setting everything up I am getting very low amts of bass output from the sub that use to be my main sub for 3 years (and was very happy how it performed)

My subwoofer (monoprice monolith 10") + marantz sr5013 AVR
-connected via RCA, tried both sub output 1 and 2 on AVR and tried both line input 1 and 2 on sub
-speakers set to small
-crossover at 80Hz both on AVR and Sub
-bass set to LFE on AVR
-subwoofer level titrated up to +2 and subwoofer needs to be cracked up to 1-2 o'clock to get any type of bass output (but still very low overall)
-tried phase from 0 to 180
-tried different RCA and power cables

I've conducted a sub crawl (while sub placed in my MLP)
Tried 4 different spot and still could not get good bass

Room is fully closed, 15' x 10' x 8' 1200 cubic feet, walls are drywall, floor is carpet-->floor board-->concrete
Sitting distance to sub is on average 6' (from all positions tried)

What's strange is:
-I tried my HSU VTF-3 MK5 sub in there and also same poor results
-I tried a Jamo J10 sub and its producing TONS of base with the same AVR / placement setup with the same RCA cable
-I know the monoprice sub works bc its works very well when connected to my BlueSound node 2i (vol at 10 o'clock)

Completely out of ideas as how to fix this issue.
Any ideas on what the underlying problem is and how to fix it?
Thanks!!
 

DanielT

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Strange that no one helped you. Hm. Okay, but all subwoofers work properly? They pump well with air? So you can exclude that bit. That they work now, that is. Those that do not work well in your current listening room, have you been happy with them before? Good with sub bass then? Then when you were happy compared to now you have the same peripherals, the same signal source in to them? Have you changed anything since you used them and thought they sounded good?

How are they designed? How are subdrivers mounted on the baffle? How are ports mounted? ... and so on are they mounted in the same way on the subwoofers? Feel free to show pictures of them. Sealed, ported?
 

f1shb0n3

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The standard recommendation would be to buy a UMIK-1 and measure the frequency response of your system with/without sub and the sub separately. This will help diagnose the issue, but also allow you to measure frequency response so you can calibrate with EQ it to conform to your preferred target.
 

DanielT

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The standard recommendation would be to buy a UMIK-1 and measure the frequency response of your system with/without sub and the sub separately. This will help diagnose the issue, but also allow you to measure frequency response so you can calibrate with EQ it to conform to your preferred target.
Absolutely for fine tuning but now they hardly seem to work at all so is there something wrong with the subwoofer itself? Or something wrong with connecting it, them?If you move around subwoofers in a room, walk around and listen and there is hardly any bass at all compared to how they have worked before so, well or so there is nothing wrong with them but it "only" is EQ that is needed.What now hardly any bass is. We'll see what
bomt697 says.

But a UMIK-1, plus EQ makes sense, even if the subwoofer itself works.:)
 
Last edited:

5-pot-fan

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Hi -
I saw this thread while looking for help on a different bass problem, so thought I should at least offer a shoulder to cry on, unless you
have you resolved your problem?
I know little about sub-woofers but suspect from what I read in this thread that the problem may lie in what has changed, but I would need some more details to go further.
Feel free to post back here if you want.
 

raindance

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The room has changed and has a different set of bass modes which will certainly change how it sounds. However, most subs on a Marantz receiver require very little volume (9 - 10 o'clock) in order to work with 87dB/watt/1m sensitive speakers (fairly average) so I'm wondering if the subwoofer cable isn't faulty. What are the main speakers?

If Audyssey calibration is succeeding in the new room, are you sitting in the exact same primary listening place as the calibration mic? Or did you forget to re-run calibration perhaps?

Also, LFE + Main seems to give best results in Marantzworld, and I use a couple of them at home.
 
OP
B

bomt697

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Hi -
I saw this thread while looking for help on a different bass problem, so thought I should at least offer a shoulder to cry on, unless you
have you resolved your problem?
I know little about sub-woofers but suspect from what I read in this thread that the problem may lie in what has changed, but I would need some more details to go further.
Feel free to post back here if you want.
I was able to fix the problem. Which was the distance was set too close. Once the distance was updated after I reran Audyssey, the distance was the only that changed and the problem went away
 

f1shb0n3

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I was able to fix the problem. Which was the distance was set too close. Once the distance was updated after I reran Audyssey, the distance was the only that changed and the problem went away
Distance setting changes the delay of the sub and that's critical for proper integration. You can use the actual distance and adjust slightly by ear, but some subs will have an additional internal delay from DSP and such. REW measurement even with non-calibrated microphone should measure the delay precisely so you won't risk getting it wrong. Simplest method - run a sweep using an acoustic reference and once the speakers chirp turn off main speakers and let the measurement measure the sub only. The delay you get in the result would be the distance difference between speakers and sub and you can convert it to feet by multiplying by 1.12533 (based on sound speed in air at room temperature) and put that in the AVR distance setting.
 

5-pot-fan

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I was able to fix the problem. Which was the distance was set too close. Once the distance was updated after I reran Audyssey, the distance was the only that changed and the problem went away
Good to know!
 
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