[surma884]

I've got a SVS PC12-NSD and Denon AVR-789 receiver. What's the best way to get tight bass out of my sub? I got 2 TSi 300 Polks for my mains. I know they are a little weak, but I thought my sub would handle it. Movies sound awesome, but music requires more tight, hard hitting bass. I don't get that with my sub. I don't care for deep bass for music. I searched the forums, but there is no thread on how to make your sub sound tight. The sub's gain is set to 11 o'clock. My AVR is set to +3 for the LFE.


Thanks

 

[mike2060]

You will probably have to move your sub or listening position around or get acoustic treatments.

 

[mcjasonb]

the "tight" sound is usually more in the midbass region. i'd say 60hz and up.


have you tried the sub in various locations to see where it sounds best?

 

[surma884]

Yeah, I tried 2 different corners in the front. Haven't tried moving it to the back. But if I'm playing a song and I'm right up next to it I can't feel the sound going through me. I'm doing a direct 2.0 setting on my receiver and my receiver is set to LFE+Main. The LFE is 120hz, the highest setting. I tried setting my mains to small and large but that did not help. Audessey on/off does not matter either. One thing I think may help is if I cover the port. I'll stick a towel or t-shirt in it to see if that makes a difference. Or does it have to be foam/sponge type?

 

[mcjasonb]

have you tried moving it out of the corner? a corner is not always the best place.

 

[switchgear]

Is 120hz your crossover point from your avr? If it is I would drop the crossover down to 80 hz to the LFE channel. On the amp on the sub make sure that the crossover switch is set to disabled. Then set phase to 0 then run your audessey again. That is how I set mine up and I think it is amazing. Also their customer support is great and they can definitely get you steered in the right direction.

 

[CT_Wiebe]

surma884 -- With the Polk TSi300, there is absolutely no reason to set the LFE at 120Hz. With the LFE set to 120Hz and your AVR-789 set to "LFE+Main" you are creating muddy mid-bass (because your PC12-NSD is being driven into it's less than linear output range).


Covering the port of your SVS PC12-NSD is not recommended. It will reduce the output capability of the sub, and destroy it's performance.


Your TSi300s should be flat to 47Hz, with response down to 35Hz. Therefore, as switchgear said, you should set your LFE to 80Hz (and no higher!). You will find that your mid-bass sound quality will be greatly improved, especially for music (it won't hurt the movie sound tracks either).


You should also try using LFE only (instead of LFE+Main). However, I assume that you have tried that first. You also should have used the Audyssey calibration built into your AVR-789. That will really help your audio performance -- that's what it is for, and is one of the best features of your Denon. Without running the Audyssey auto calibration, you are just "shooting in the dark" (so to speak).

 

[goneten]

Here are my thoughts : if you want tighter bass out of the PC-12-NSD you will want to invest in bass traps. It will make the largest perceptual improvement there is in terms of tightness and articulation.


Regards,

 

[CT_Wiebe]

goneten -- There is no need to invest in bass traps, until he gets the basic speaker setup and adjustments right.


His Polk TSi300s should be placed at least 4" from the walls (so their rear vents can work correctly). His LFE needs to be set correctly and the Denon's Audyssey calibration should be run. Otherwise, he won't get the most out of what he already has.


Then, and only then, should bass traps (or equivalent) be attempted, if needed, to tame a difficult room. Using bass traps to compensate for incorrect speaker/AVR setup is a poor use of resources.


After working with speaker systems for over 50 years, I have found that correct speaker location can solve a large majority of audio performance problems.

 

[goneten]

CT_Wiebe,


Speaker or subwoofer positioning will do little to alleviate issues with low frequency ringing within the room. You can position the subwoofer for cleanest bass with the flattest response and still end up with poor decay times that result in sluggish or boomy bass at the seats.


If you want to treat the underlying issues then you need to dampen those issues at the source. It's that simple. He can play around with BM settings all day long until he is blue in the face; it still isn't treating the underlying cause of the problem which, 99.9% of the time, are time-related acoustic issues.


I also wouldn't recommend placing his mains at least 4" away from the wall but at least .5-1m away from the room boundaries. A 4" clearance is far too small; in my opinion, it's so small you might as well not even bother with it. Placing treatment behind the speaker to treat SBIR will make more of an improvement than any placement or BM setting could provide.


I haven't been working with speaker systems for 50 years but I know enough to know that acoustic treatment (especially bass traps) are the solution to 99% of all sound quality related issues within a room and especially tackle the issues pertaining to sluggish, boomy and/or inarticulate bass.


Regardless, even if the system was set up incorrectly, bass traps would still provide a most beneficial improvement to system ringing which no amount of positioning, playing around with BM settings or Audyssey could provide.


Regards,

 

[gtpsuper24]

To the OP I would first do what CT Wiebe suggested. But you should invest in bass traps at least in the front two corners like goneten said. I have the same sub as you 25-31pci older model, and had same problem you kind of described a lack of "slam" or "punchiness" I did superchunk bass traps in the front two corners, 12 panels of OC 703 2" and cut them in 17"x17"x24" triangles and stacked them 96" high in each corners each panel will get you 16" in height going with that size triangles. Also get a Auralex gramma pad (subdude) it helps isolate the sub from vibrating a wooden floor.

 

[surma884]

I just set my LFE to 120hz a couple days ago. Before I had it set to 80hz. I will try this test: Set LFE to 80hz then run Audessey. I had run Audessey 2 times before but I don't remember what my LFE was set to. I can't set the speaker config to LFE because I will be playing music (2.0). So I have to keep it at LFE+Main. Would setting the crossover for my Mains changing anything? I think right now I have my mains set to 40hz.


I think I'll also try a shorter sub cable. I've got a thick 25ft cable. I wonder if the pre-amp signal is getting weaker over that distance.

 

[jsmiddleton4]

"Set LFE to 80hz then run Audessey."


I'm pretty sure Audessey will reset it. I encourage you to read the Audessey thread in the AMP section.

 

[Snowmanick]

A couple thoughts on getting the most out of your system.


1) The LFE setting is irrelevant to music unless you are referring to multichannel audio with specifically encoded material for the LFE channel. Leave the LFE setting at 120 Hz as it is the low pass filter for the LFE channel for movies and is spec'd to 120 Hz but many AVR manufacturers incorrectly auto-set it to 80 Hz (and many people mistakenly think it is a crossover when it is not).


2) Keep your speaker settings at small, most likely an 80 Hz crossover or so (60Hz may sound better but 80 Hz is an easy place to start).


3) Verify the phase settings on your sub are correct (incorrect phase can have the sub fighting the mains as opposed to working in conjunction with them)


4) Move the sub out of the corner as it may be making the bass sound bloated/boomy, try placing it at 1/3, 1/5 or 1/7 intervals across the wall.


5) Set your bass setting to LFE only, not LFE+Mains.


6) Experiment with moving your mains off the wall, the .5 meter to 1.0 meter recommendation is not a bad rule of thumb to ball park where to start. Placing your speakers too close to a wall bloats the midbass and bass from the speakers.


7) Experiment with your seating locations as well, one recommendation is to try to keep your listening position 38% into the room from either the front or rear walls. While that is not practical for all rooms, keeping the seating position away from the walls will help with all aspects of your systems imaging, especially bass performance as bass tends to become exaggerated/boomy/bloated near boundaries.


8) Read the Audyssey set up thread for specific recommendations on how to optimally run Audyessey.


These are all free and can be useful to get the best performance out of your system, they also translate pretty well for most rooms. After proper placement of your system/yourself and Audyssey set up (which is more of a process than many manufacturers try to make it out to be) then you can start looking at other options such as bass traps (which are almost always beneficial but not a panacea) and sub EQ.