Key takeaways
- Channel count sold on its own is meaningless without checking whether the room can actually use the extra channels.
- A total watts figure on the box says almost nothing about how clean or how loud a soundbar will sound in practice.
- Guessing at bar width instead of measuring the shelf is the single most common return reason installers see.
- PCM instead of bitstream quietly strips Atmos and DTS:X metadata even when every cable and port is correct.
- Deciding on a subwoofer after delivery, rather than before ordering, usually costs a second shipping charge.
Every service call starts to sound the same after enough of them: a soundbar bought last month, unboxed with real excitement, already disappointing somebody in the house within a week. Almost never a broken unit. Almost always one of six decisions made before the box was ever opened.
None of these mistakes are stupid. Each one feels like the reasonable choice standing in an aisle or scrolling a listing at midnight. That is exactly why they keep happening, and why naming them plainly is more useful than another spec sheet.
Mistake 1: Buying on channel count alone
A bigger number feels like a safer bet. A 7.1.4 bar looks like it must outperform a 5.1 one, so it goes in the cart, especially once it is on sale near a flagship price point.
What it costs: height and rear channels that a small apartment living room, often under about 20 square metres with a 2.3 metre ceiling, has no space or surface to use properly. The buyer paid for four extra channels that are, in practical terms, doing almost nothing audible from the couch.
The correction is to size channel count to the room, not the shelf display. What each number in 2.1, 5.1, and 7.1.2 actually changes is worth reading before comparing prices, since the jump from 2.1 to 5.1 matters far more in most rooms than 5.1 to 7.1.4 ever will.
A useful rule of thumb: measure your ceiling height and your floor area before you shop, and treat those two numbers as a filter on which channel counts are worth paying for. A room under about 20 square metres rarely rewards anything past 5.1.2, no matter how the box is marketed.
Mistake 2: Trusting the total watts on the box
A single number, 300 watts against a competitor’s 600, looks like an easy comparison. It is not, and manufacturers know that most shoppers will read it that way anyway.
What it costs: a bar that measures louder on a spec sheet but sounds thinner or more strained at real volume than a lower rated competitor, because total system wattage is usually a sum across every driver added together, sometimes at peak rather than sustained output, not a measure of clean loudness at your seating position.
Two bars can share an identical wattage figure and sound noticeably different once pushed past conversational volume. Driver size, cabinet design, and amplifier headroom decide that gap, not the number printed on the box.
The correction is to listen before buying wherever possible, or lean on independent measurements rather than the spec sheet’s own wattage claim. A demo of one loud scene at your normal volume tells you more in thirty seconds than any number on the packaging.
If a showroom demo is not an option, a manufacturer’s own decibel rating at a stated distance, when they publish one, is a more honest number than total watts. Most do not publish it clearly, which is itself worth noticing before you buy on watts alone.
Mistake 3: Guessing at width instead of measuring the shelf
Ordering online without a tape measure feels harmless. The bar in the photo looks proportional next to a television roughly the same size as yours, so it should fit.
What it costs: a bar too wide for the shelf, overhanging the edge and becoming a genuine hazard, or one too deep that blocks the TV’s front facing infrared sensor. This single mistake accounts for more returns than any other on this list, by a wide margin, in my own experience fitting these.
The correction takes two minutes: measure the TV’s screen width corner to corner, not the diagonal on the box, and measure the shelf’s depth before ordering anything. The full working range for matching bar size to screen size covers this with real examples across several TV sizes.
Mistake 4: Assuming any HDMI port carries the same signal
Plugging into whichever HDMI port is free feels like it should not matter. HDMI is HDMI, and the cable either works or it does not, or so the assumption goes.
What it costs: silent or downgraded audio, because only one HDMI port on most televisions is labelled ARC or eARC, and using the wrong one leaves the soundbar unable to receive a return audio signal from the TV at all. HDMI’s own specification body documents exactly which capabilities each port version supports, and it varies more between TV models than most buyers expect.
The correction is to check the TV’s manual for which specific port is marked ARC or eARC before connecting anything, and to confirm what that connection actually adds over optical if disc based lossless Atmos or DTS-HD Master Audio matters to you.
Mistake 5: Leaving the TV set to PCM instead of bitstream
This setting hides inside an audio menu most people never open after initial setup, so it stays on whatever the TV shipped with, which is often PCM by default.
What it costs: Atmos or DTS:X that the box promised and the HDMI connection can technically carry, quietly stripped down to standard stereo or 5.1, because PCM means the television has already decoded the audio itself before sending it onward. That decoding removes the object based metadata Atmos and DTS:X depend on.
The correction is a single menu change: set the TV’s digital audio output to bitstream, sometimes labelled passthrough, rather than PCM, whenever a soundbar or receiver is doing the decoding. The full breakdown of which setting suits which setup covers the cases where PCM is actually the right choice instead.
A quick way to confirm the setting stuck is to check the soundbar’s own display or app during playback of a known Atmos title. Most bars show an indicator, a small Atmos or DTS:X icon or a text readout, the moment the format is actually detected on the incoming signal.
Mistake 6: Deciding on a subwoofer after the soundbar arrives
Ordering the bar first and figuring out the subwoofer question later feels like it splits a big decision into two smaller ones. It usually does the opposite.
What it costs: a second delivery, a second unboxing, and sometimes a bar that turns out not to support the specific wireless subwoofer the buyer wanted to add, since pairing is largely locked to each brand’s own ecosystem rather than being universal.
The correction is deciding on the subwoofer question before ordering the bar, not after. Whether your room and viewing habits actually call for one is worth settling first, since it changes which specific bar or bundle is worth ordering in the first place.
It is a cheap check compared with the cost of guessing wrong. A bundle with a matched wireless subwoofer, bought once, is almost always less hassle than a bar bought alone and a third party subwoofer added under pressure once the household has already noticed the bass is missing.
- Match channel count to your actual room size, not the biggest number available
- Ignore total watts as a sole comparison point between two bars
- Measure screen width and shelf depth before ordering anything
- Confirm which HDMI port is ARC or eARC on your specific television
- Set the TV to bitstream or passthrough, not PCM, once the bar is connected
- Settle the subwoofer question before the bar ships, not after
Fixing all six of these costs nothing but ten minutes with a tape measure and a menu screen. A sensible tier by tier upgrade path is a reasonable next stop once these six are handled, since it assumes you have already avoided the mistakes that waste money regardless of which tier you choose.
Questions readers ask about this
Not always, but it is wasted often enough to check first. A 5.1.2 or 7.1.4 bar in a room under about 20 square metres with a low or textured ceiling delivers little audible benefit over a well matched 5.1 system, so the extra cost buys very little unless the room genuinely supports it.
Total watts is usually a sum across every driver, sometimes measured at peak rather than sustained output, which tells you little about clean loudness. Driver size, cabinet volume, and amplifier headroom decide how a bar actually sounds under real volume far more than the printed wattage figure does.
Very common, since most televisions have between two and four HDMI ports but only one labelled ARC or eARC, often without clear on screen labelling. Checking the TV's own manual for the exact port number takes under five minutes and avoids a silent or downgraded audio connection entirely.
Nearly all TVs from the last several years do, usually inside a digital audio output or HDMI audio menu, though the exact wording varies by brand. Some older or budget models default to PCM only and cannot be changed, which is worth checking before assuming a setting is simply hidden.
Within a standard return window, yes, particularly for a clear mismatch like height channels under an unusable ceiling. Past that window, reselling privately or adding a compatible accessory later is usually more practical than replacing the whole unit outright.
About the author
Rahul Gupta
Rahul Gupta has spent nearly a decade quietly wiring living rooms, testing soundbars in every awkward apartment layout imaginable, and untangling the kind of HDMI handshake problems that make people give up on Atmos altogether. He writes here about what actually works when you get the boxes home—not what the spec sheet promises. If a piece of gear on this site earns a recommendation, it earned it in a real room with real furniture, not a lab.
