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JBL Studio 625C for $219 -- 2-Way Loudspeaker with Compression Driver tweeter & Dual 5.25” woofers
$219
$495
55% off
Amazon
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If you absolutely cannot fit its larger brother the 665C as your center speaker, this will do in a pinch, and at half the cost.
If you can fit the 665C as your center but can't do the JBL 680, 690, or 698 towers for L/R, this 625C can be turned vertically and used as L/R mains---the extra woofer provides indisputable "no replacement for displacement" benefits over its single woofer bookshelf brothers the 620 and 630, and is a no-brainer at this clearance price.
Pretty much ANY 2/2.5-way MTM center speaker can be turned vertical and used as mains. Most speaker companies will never tell you that because they'd rather make more per-unit profit selling you pricier towers and bookshelf speakers, which is why these MTM speakers are almost always * marketed * as "center speakers" --- some notable exceptions are the Ascend 340SE2 and KEF Q6 Meta.
All JBL Studio 6 speakers on sale here: https://slickdeals.net/search?q=jbl+studio&...
https://www.amazon.com/JBL-Studio...0BJTKS
If you can fit the 665C as your center but can't do the JBL 680, 690, or 698 towers for L/R, this 625C can be turned vertically and used as L/R mains---the extra woofer provides indisputable "no replacement for displacement" benefits over its single woofer bookshelf brothers the 620 and 630, and is a no-brainer at this clearance price.
Pretty much ANY 2/2.5-way MTM center speaker can be turned vertical and used as mains. Most speaker companies will never tell you that because they'd rather make more per-unit profit selling you pricier towers and bookshelf speakers, which is why these MTM speakers are almost always * marketed * as "center speakers" --- some notable exceptions are the Ascend 340SE2 and KEF Q6 Meta.
All JBL Studio 6 speakers on sale here: https://slickdeals.net/search?q=jbl+studio&...
https://www.amazon.com/JBL-Studio...0BJTKS
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If you absolutely cannot fit its larger brother the 665C as your center speaker, this will do in a pinch, and at half the cost.
If you can fit the 665C as your center but can't do the JBL 680, 690, or 698 towers for L/R, this 625C can be turned vertically and used as L/R mains---the extra woofer provides indisputable "no replacement for displacement" benefits over its single woofer bookshelf brothers the 620 and 630, and is a no-brainer at this clearance price.
Pretty much ANY 2/2.5-way MTM center speaker can be turned vertical and used as mains. Most speaker companies will never tell you that because they'd rather make more per-unit profit selling you pricier towers and bookshelf speakers, which is why these MTM speakers are almost always * marketed * as "center speakers" --- some notable exceptions are the Ascend 340SE2 and KEF Q6 Meta.
All JBL Studio 6 speakers on sale here: https://slickdeals.net/search?q=jbl+studio&...
https://www.amazon.com/JBL-Studio...0BJTKS
If you can fit the 665C as your center but can't do the JBL 680, 690, or 698 towers for L/R, this 625C can be turned vertically and used as L/R mains---the extra woofer provides indisputable "no replacement for displacement" benefits over its single woofer bookshelf brothers the 620 and 630, and is a no-brainer at this clearance price.
Pretty much ANY 2/2.5-way MTM center speaker can be turned vertical and used as mains. Most speaker companies will never tell you that because they'd rather make more per-unit profit selling you pricier towers and bookshelf speakers, which is why these MTM speakers are almost always * marketed * as "center speakers" --- some notable exceptions are the Ascend 340SE2 and KEF Q6 Meta.
All JBL Studio 6 speakers on sale here: https://slickdeals.net/search?q=jbl+studio&...
https://www.amazon.com/JBL-Studio...0BJTKS
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If anything, turning an MTM vertical should actually IMPROVE the sound because it virtually eliminates the "lobing effects" Center speaker lobing refers to direction-dependent peaks and nulls in the frequency response caused by interference between multiple drivers reproducing the same frequencies. It is most commonly discussed with horizontal MTM center speakers (midwoofer–tweeter–midwoofer).
AI details:
---
1. The mechanism (why lobing happens)
In many center speakers the layout is:
woofer – tweeter – woofer (horizontal)
Both woofers reproduce the midrange up to the crossover point with the tweeter. Because the woofers are physically separated, their sound arrives at slightly different times depending on listening angle.
At some angles:
The waves add constructively → response peak
The waves cancel → response dip (null)
This produces a lobing pattern in the horizontal plane.
Technically this is a form of comb filtering caused by driver spacing relative to wavelength.
Example:
crossover ≈ 2 kHz
wavelength ≈ 6.8 inches
woofer spacing often ≈ 10–14 inches
That spacing is large enough that off-axis cancellation occurs within the speech band (1–4 kHz).
---
2. What it looks like in measurements
Measurements of many horizontal MTM centers show:
On-axis response: reasonably flat
15–30° off axis: dips in the 1–3 kHz region
>40° off axis: large cancellations
This is why you often see polar plots with multiple horizontal lobes and nulls.
---
3. How audible it actually is in real home theater use
For the center seat
Usually not very audible.
If you're near the acoustic axis:
the lobing nulls occur off-axis
dialogue clarity is typically fine
This is why many people never notice it.
---
For off-axis seats
It can become very audible.
Typical symptoms:
dialogue sounds thin or hollow
consonants lose clarity
voices sound phasey
intelligibility drops
This occurs because the 1–4 kHz speech intelligibility band is exactly where the cancellations often occur.
---
Room reflections make it worse
Even if you sit on axis, side wall reflections arrive off-axis.
Those reflections contain the lobing dips, which can slightly reduce clarity or change timbre.
---
4. How big the problem is (in practice)
In a typical living room:
Seating position Audible effect
Dead center Usually minimal
±15° Slight timbre change
±25–30° Noticeable dialogue degradation
Wide couch seating Often obvious
This is why some reviewers say horizontal MTM centers have "narrow dialogue sweet spots."
---
5. Designs that avoid lobing
Several approaches reduce or eliminate it.
1. 3-way center speakers
Example layout:
woofer – mid – tweeter – mid – woofer
The midrange is vertically aligned with the tweeter, so the interference problem disappears.
Examples:
JBL Studio 625C Center Channel Speaker
ELAC Uni‑Fi UC52 Center Speaker
These maintain wide horizontal dispersion.
---
2. Coaxial drivers
Tweeter is mounted inside the midrange.
Examples:
KEF R2c Center Channel Speaker
KEF Q650c Center Speaker
This produces very uniform dispersion.
---
3. Vertical speaker used as center
The best solution acoustically is simply using the same vertical speaker as L/R, but it's often impractical under a TV.
---
6. Why horizontal MTM centers still exist
Three reasons:
1. Furniture constraints (fit under TVs)
2. Marketing aesthetics
3. Cost (true 3-way centers cost more)
Even though the acoustic compromise has been known since the 1970s.
---
7. Real-world severity
In the home theater community (including forums like AVS Forum), the consensus is roughly:
Single seat users: rarely a major issue
Wide seating rows: can be a significant limitation
High-performance systems: enthusiasts prefer 3-way or coaxial centers
---
✅ Bottom line
Lobing is a real acoustic artifact caused by woofer spacing in horizontal MTM centers.
It mainly affects off-axis listeners.
For a single prime seat it's often minor; for multiple seats it can noticeably reduce dialogue clarity.
---
If you want, I can also show you why the problem gets dramatically worse above ~1.5 kHz with a quick wavelength vs driver spacing explanation (it's surprisingly simple physics).
However, it's important to understand what actually changes.
---
1. What happens when an MTM is horizontal
Typical center speaker layout:
woofer – tweeter – woofer
When placed horizontally:
the two woofers are separated left–right
interference occurs across the seating area
Result:
horizontal lobing
off-axis listeners experience cancellations in the 1–3 kHz speech band
That's why dialogue clarity drops for seats away from center.
---
2. What happens when the same speaker is vertical
Rotate the same MTM 90°:
woofer
tweeter
woofer
Now:
driver spacing is up–down
interference moves to the vertical plane
Result:
horizontal dispersion becomes smooth
people sitting left/right hear a consistent response
This is why vertical speakers work much better for multi-seat listening.
---
3. Why vertical lobing is less audible
Vertical cancellation occurs between:
ear height
floor reflections
ceiling reflections
But listeners usually remain within a small vertical angle range (±5–10°).
By contrast, horizontal seating angles often reach ±30° or more.
So the problematic nulls are rarely encountered.
---
4. This is why L/R speakers are almost always vertical
Nearly all conventional speakers (bookshelf or tower) are MTM-like in radiation behavior:
midrange drivers near a tweeter
crossover around 1.5–3 kHz
Placed vertically, they produce:
wide horizontal dispersion
controlled vertical dispersion
This is the desired radiation pattern for stereo and home theater.
---
5. Important nuance
Vertical MTM still has vertical lobing, which can matter if:
the speaker is far above or below ear level
listeners sit on different floor heights
the crossover frequency is unusually high
But in typical rooms the effect is minor compared with horizontal lobing.
---
✅ Bottom line
Rotating an MTM vertically does not eliminate lobing.
It moves it into the vertical plane, where it is far less audible.
This is why many enthusiasts prefer three identical vertical speakers across the front instead of a horizontal center.
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Much easier for these used car salesman to come in and promise these $400 speakers are as good as $3-$4k speakers!
Regurgitating something they read as proof LOL!
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