Just to be sure, when you look at Settings>System>(room name), what shows up after the room name?

If you then click on the name of the room, then click on Sub Audio, do you get any controls (Sub level and phase)?

Have you run TruePlay on the room?

Have you considered moving the sub to a different location in your physical room?

Regardless of where you place the Sub, if you lay your palm over the opening at the centre, you should feel the air moving against your palm, even with the Sub set to mid position - can you?

PS: Have you added the Sub to the SL pair via the control app?

Thanks for your reply. Plese find my response below.

Q1) Just to be sure, when you look at Settings>System>(room name), what shows up after the room name? 

(L+R+Sub)

Q2) If you then click on the name of the room, then click on Sub Audio, do you get any controls (Sub level and phase)?

Only Sub Level 

Phase Control is disabled

Q3) Have you run TruePlay on the room?

Yes

Q4) Have you considered moving the sub to a different location in your physical room?

Not yet. Due to requirement of power source, I’m bit constrained. Is there guideline on where to place the Sub?

Hi Kumar, thanks for yoru reply. Plese find my response below

Q1)  if you lay your palm over the opening at the centre

Yes. The membrane also vibrates.  

Q2) Have you added the Sub to the SL pair via the control app?

Yes

@Koustav,

Try switching off TruePlay and perhaps boosting the sub level to a higher, or it’s highest value and don’t forget there is a Bass slider adjustment in the attached rooms EQ settings too, that you can choose to increase, or decrease, to suit your listening needs. However I suspect just the act of switching off TruePlay ‘might’ provide the answer you’re looking for here.

Hi Ken

Switching off Trueplay did indeed improve bass effect from Sub. Thanks a lot for suggesting this. 

Should I be bothered that I'm listening without Trueplay?

It’s not uncommon for users of Digital Room Correction (e.g. Trueplay) to feel that the bass gets significantly reduced. Perhaps they’re used to the familiar boom of the room’s resonances, which Trueplay does its best to eliminate. 

After Trueplay has smoothed out the response curve one should be able to tilt it up in the lower frequencies by tweaking the suggested EQ and Sub settings.

TruePlay is doing its level-best to tune your speakers to the room, but you can achieve the same, or perhaps a more desired outcome by manually adjusting the available EQ settings yourself.. I have a mix of Sonos rooms each with TruePlay enabled and not enabled, as in some I prefer it, but in others I don’t. So if you’re happier without TruePlay enabled, I would leave it switched off. Always go with what you prefer to listen to, is what I would recommend.

Not quite. Trueplay is based around a 16-filter parametric EQ, which is much more granular than the simple EQ settings available in the controller.

Trueplay tuning the Sub usually makes for a more natural bass, with bass bloat removed. At first, this may have you think that the bass is too thin, if you are accustomed to the exaggerated bass that is common in many cheap systems.

I suggest you let the music you like play with True play ON for a couple of weeks, after perhaps moving the Sub audio level a couple of notches to the right. Once that time is over, turn Trueplay off, and see if OFF is what you still prefer. If so, leave it off and enjoy the music that way. And then you should not be bothered that you are not using True play.

Thanks Kumar, Ratty, Ken for your inputs. I will try them out.