PlanetaryReference
Established Member
I'm hoping someone can help me out here because my sub sounds way too loud, even on the lowest settings. It sounds exaggerated on the lower frequencies. It rumbles far too much. Is this a defect?
It's not your imagination, nor a defect, as I'll show.
The main problem with the sub's output when in the usually shown orientations within the Samsung ad imagery (i.e. thin front side facing the listener seating position) is asymmetric output. If it's in a corner as well oriented that way it sounds very asymmetric (undermines the surround image symmetry in the process), plus it sounds terrible in a corner due to coupling resonance.
People may hear the sub's sound in all room listening locations, but they sure won't be hearing it at equal amplitude in all locations.
A partial solution to its output asymmetry is to orient the sub in one of its most symmetrical output orientations, plus to locate it in the most symmetrical location in the room (as far from a corner or wall/floor 90 degree as you can manage).
Many people can't or just won't do that. And this sub sounds a bit boomy to rumbly and disappointing if you don't.
I found the most symmetrical sub frequency output orientation to be with the driver’s cone pointing upward, plus this also gave the best lower-mid dispersion, and with the port facing the center of the room (optional), i.e. an orientation that you will never see in any Samsung promo ad image.
I also lifted the lower side of the sub off the floor by ~20 cm, with an open structure under it, to eliminate resonant coupling with the floor (which works well to help reduce most of the boominess and resonant rumble).
Mine is in that orientation in a mid-wall location, and as far from a corner, or 90 degree angle, or 'cavity', as possible. This gave both the best dispersion across the room, with the least boominess and best clarity. I’m OK with it like this. But most people either can't nor won't do this, for various practical or aesthetic reasons.
Most soundbar subs will have similar output asymmetry limitations as this one. The down-firing JBL and the Bose will have less output asymmetry (thus both have real nice sounding subs), plus the Sonos Arc's sub will have about the least output asymmetry, due to its novel duel-driver design which was clearly produced to eliminate as much of the sub’s output asymmetry across a room. By all accounts it works very well, and I don't doubt it (but the frequency range is not great).
But for the current Samsung or LG sub they will need careful placement, and more optimal symmetrical orientation to get the best out of those.
I do find it odd that specialist sub manufacturers make a big deal out of getting the internal aspects of a sub’s design sounding good, but then often leave the external output sound asymmetrically distributed across the room.
IMO the Q950T sub has a good amp, and a strong driver, but the cabinet's design leaves a lot to be desired. It is not good at all. It has the typical internal standing-wave effects of small cheap subs, which you have to counteract with a lot of EQ to flatten them out, plus strong external asymmetry in its conventional marketed orientation position.
Out of the box, in the advertised orientation, I would give the Q950T sub 4.5/10 for sound quality.
But in a more symmetrical output orientation, with a lot of corrective EQ I'll give the sub 9/10 for sound quality. It can be turned from a bit of a flop, into a very capable sub.
Location, orientation and EQ really matter with this sub, but the Q950T has zero sub EQ-ing options out of the box. Next year’s Q950A appears to use the exact same sub, but with corrective auto EQ optimization added to it.
Which will be better, possibly a whole lot better, depending on how flat the output EQ curve is and the time taken in the coding to get that right (yeah ...). But even then the sub's cabinet design will have the same output asymmetry as now, and require a better orientation to sounding its best across any room, before the room EQ is even corrected for.
Hopefully they give it a fully symmetrical sub design in 2022's model though. I would give it an upward firing cone, plus a symmetrical port around its base, plus elevate it off the floor with extendable folding legs on each corner to reduce the floor coupling resonance. Plus the auto-correction room EQ included of course. The 11.1.4. image would be greatly enhanced by such a symmetrical output smooth sub.
Nevertheless, right now I can get that sort of extremely satisfying sound quality out of the Q950T sub, but only via symmetric orientation, placed in a symmetric location in the room, with a lot of precise corrective EQ applied, to remove its internal standing wave cancellation and peak issues.
The good news is this Q950T sub does respond extremely well to doing that, and produces a genuinely mega sounding bottom-end (think Bose sound quality sub output, but perhaps clearer). But the EQ needed to get this sound quality level is detailed, with a lot of cuts and boosts needed to smooth it to flat it and make it clear and musical sounding (rather than the tonal resonance dominated sound it produces out of the box).
Here’s the setting I use on my PC’s output EQ-ing, using the Equalizer APO app, to get the sub to work to perfection, with all forms of music that I feed it.
Hz | dB
14 3.13
16 5.71
18 6.01
20 4.61 (bands below 20 Hz shape the end of the EQ filters curve)
25 7.18
32 -32.23
36 2.39
41 4.67
51 -6.86
61 -14.04
71 -18.40
78 8.89
87 -20.93
91 -1.07
95 5.17
100 7.29
107 9.64
112 6.25
117 -22.72 (sub contribution is gone above ~117 Hz)
124 1.86
128 -27.57
138 1.87
145 -4.91
165 -6.51
204 -3.87
275 -1.24
364 -7.00
463 -9.95
562 -14.68
739 -14.99
973 -12.52
1564 -10.78
1970 -9.48
2446 -9.28
3370 -7.14
3817 -8.16
4319 -7.51
4924 -9.16
5651 -4.05
8277 -2.75
8783 -4.45
12319 -3.94
12975 -5.77
13931 -5.68
18217 2.00
20000 2.00
The two decimal places in this setting is in fact the audible change level, and does matter to the sound quality and musicality of the sub. Like the bar's small drivers, this sub’s 8-inch driver is extremely sensitive to small changes in EQ at the right frequency center, to counteract its internal standing-waves. It’s the cabinet design and the lack of system EQ, currently for this Q950T sub and system, which is the problem. The driver and amp are both very strong, deep and clean. But they are in a cheap compromised asymmetric cabinet design, which lets them down badly.
The cabinet is very much the weak link. In fact I would love to experiment with putting the driver and electronics into a custom-made cabinet of my own design and construction, as I'm sure I could make a vastly improved sub enclosure for the Q950T, in that way. But I have it working very well now with the EQ setting, so probably won't bother. But don't go thinking the 8-inch driver is not up to it, because it's real nice sounding once the EQ is sorted.
Samsung can make it better (potentially a lot better) with the 2021 Q950A model's adding sub EQ-ing, but the real solution will be to put this amp and driver, plus the new EQ functionality, into a far better and more symmetrical output cabinet. The resulting sub would match or exceed any ATMOS sound bar in 2022.
But for now, we have to get the best we can out of the existing design and its system limitations (no sub EQ).
This is the sub response the above setting describes:
So you're not imagining a low-end spike in the Q950T's sub, there is one and as you can see (visually), it's not small. If your room's natural resonance is also in the same peaking range, then you are going to hear a sympathetic room resonance response from it stimulating the room's angles and surfaces to act like a resonant 'sounding board'.
I removed that internal peak, and the other smaller ones, with the settings given above for my PC's A/V HDMI out to an LG TV, then ARC out to Q950T.
Samsung HW-Q950T and HW-Q900T Soundbar - Review & Comments
I have the LG CX i have try cyberpunk and gears 5 so far if you have any request i can always see if i have the game and check it out for you.I don't think this samsung issue sounds like a LG issue cause as soon as the firmware came out like 2 firmware before my current ones i was like you...
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