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Monoprice THX-365C Center Channel Speaker Review (by Erin)

GabrielPhoto

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I tried the UC52 in my room and it was seriously insensitive. Audyssey calibration resulted in -0.5db levels when center listening position was just 1.9m away. Otherwise it sounded like it had much better imaging than the usual 2 way centers. Pity its so power hungry.
Interesting. I will be testing it in about 20 minutes finally. Compared to the Klipsch RC-7, RC64 iii and 504c , it is going to be a very different power need for sure. I already returned the 520c so cannot test that one any more but not like I really wanted to keep it much longer :D
 

jhaider

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Turn it 90 degrees and stack on a Monoprice sub for a kind of current-day NHT Evolution T6?
 

Benedium

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Interesting. I will be testing it in about 20 minutes finally. Compared to the Klipsch RC-7, RC64 iii and 504c , it is going to be a very different power need for sure. I already returned the 520c so cannot test that one any more but not like I really wanted to keep it much longer :D
My guess is it would still be best to get matching brand and series of L/R speakers to use with your chosen center speaker. I even need surround speakers to match cos they can sound pretty dominant in my room too.
 

GabrielPhoto

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My guess is it would still be best to get matching brand and series of L/R speakers to use with your chosen center speaker. I even need surround speakers to match cos they can sound pretty dominant in my room too.
nah, that 520c sounds nothing like the 590s. I would need a 590 to match in the center and that aint happening any time soon until one day if I can setup an AT screen :D
 

abdo123

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Depending on the room reflections it is possible to hear such lobe/dips even in the "good angle region".
That’s a big eeeeeeh from me. Most off-axis radiation is generally pretty crazy by 50-60 degrees off-axis and it’s generally fine imo.

The speaker has a a healthy 50 degrees beamwidth and it’s honestly fine.
 

thewas

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That’s a big eeeeeeh from me. Most off-axis radiation is generally pretty crazy by 50-60 degrees off-axis and it’s generally fine imo.

The speaker has a a healthy 50 degrees beamwidth and it’s honestly fine.
Well, that's your opinion and experience and mine is different, by the way I have designed and built myself a 3 way loudspeaker with a similar 2" mid dome and have similar problems on the vertical axis (despite using just one woofer). As said it depends though also a lot on the reflectivity of the room. If only 50-60° would matter we spare ourselves so many measurements and just make "cinemascope format" directivity plots. :-D
 

abdo123

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Well, that's your opinion and experience and mine is different, by the way I have designed and built myself a 3 way loudspeaker with a similar 2" mid dome and have similar problems on the vertical axis (despite using just one woofer). As said it depends though also a lot on the reflectivity of the room.
I just think the diffraction (what is it exactly?) at 1KHz is the real party pooper here since that's what we're most sensitive to.

The horizontal polar plot looks fine as hell within ~3dB.

Monoprice%20Monolith%20THX-365C_360_Horizontal_Polar.png
 

thewas

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Monoprice%20Monolith%20THX-365C%20Horizontal%20Contour%20Plot%20%28Normalized%29.png

The 2 yellow lobes at 100° mean that there the phase different of the drivers is around 180° creating cancellations and even at 50° phase difference will be already quite high, this can create some audible "special effects".

The round plot you show above is not normalised and imho not so helpful in that range but also shows the sudden widening around 700 Hz:

1647587583383.png
 

abdo123

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Monoprice%20Monolith%20THX-365C%20Horizontal%20Contour%20Plot%20%28Normalized%29.png

The 2 yellow lobes at 100° mean that there the phase different of the drivers is around 180° creating cancellations and even at 50° phase difference will be already quite high, this can create some audible "special effects".

The round plot you show above is not normalised and imho not so helpful in that range but also shows the sudden widening around 700 Hz:

Monoprice%20Monolith%20THX-365C_360_Horizontal_Polar.png
that lobing is just inherent to the design though, even the 8361A shows lobing at ~100 degrees similar to this. iIn my opinion it's the correct compromise considering the speakers great sensitivity and the compression test results.

index.php
 

thewas

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that lobing is just inherent to the design though
As said it is a result of the mid dome which cannot be crossed lower, with a small cone mid driver which could be crossed quite lower (like for example at 300 Hz) it wouldn't be an issue.
even the 8361A shows lobing at ~100 degrees similar to this
These are really not comparable, as on 8361A it is on the vertical axis (which isn't as audible) and the directivity doesn't by far make such a big jump as its also similarly narrow above.
 

abdo123

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and the directivity doesn't by far make such a big jump as its also similarly narrow above.
That was kind of my point and what i was trying to say. This wouldn't be as much of an issue

1647594602229.png

If this didn't exist.

1647594557211.png


People are far more likely to hear the resonance/diffraction/whatever that is than they're likely to hear the lobing.
 

Sancus

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The lobing is certainly a feature when controlled properly, Genelec even directly states it's an intentional part of the design to improve low frequency directivity.

The Kef Reference 4C also has it, but again, directivity above it is much better controlled.

Regardless though, almost all the centers at this price range are crap so this one is actually really good. Only the coaxials have better directivity, but they usually have more compression or distortion than this. Plus on axis flaws sometimes.
 

sword

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At this price, it's the best measured center speaker with a horizontal form factor that I've seen. I had one for awhile and can confirm it can play at reference level really well.
 

gbrnole

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i still remain convinced that a single KEF Q350 used horizontally is the best center speaker money can buy in this budget category. KEF doesn't sell the Q350 in singles but they can be found without too much effort.

Monolith is yet again turning heads and proving itself to be a worthy competitor in a crowded market and stamping that authority with, on price / performance ratio, very good value for money. I'd love it if they had a base white cabinet option too.

i guess the next two center speakers that i would love to see results for are the SVS Ultra Center and Aperion Novus Center. I suspect the SVS Ultra Center might more closely mimic its Ultra stablemates - not a bad place to be. it would be nice to see a plot for the older Polk LSiM Center speakers too but that is probably stretch at this point.
 

GabrielPhoto

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I tried the UC52 in my room and it was seriously insensitive. Audyssey calibration resulted in -0.5db levels when center listening position was just 1.9m away. Otherwise it sounded like it had much better imaging than the usual 2 way centers. Pity its so power hungry.
You were not kidding about the ELAC. Where my RC-7 I had it at -1 in the Denon 4400h for 75-76db the ELAC needs me to push it to +9.
The monolith is out for delivery finally. Cant wait!
 

gbrnole

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You were not kidding about the ELAC. Where my RC-7 I had it at -1 in the Denon 4400h for 75-76db the ELAC needs me to push it to +9.
The monolith is out for delivery finally. Cant wait!
yeah ELAC fixed the lack of sensitivity in the UC52 with the UCR52 and introduced a whole slew of new problems in the process. The UCR52 can be helped with DSP but not an ideal solution.
 

GabrielPhoto

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i still remain convinced that a single KEF Q350 used horizontally is the best center speaker money can buy in this budget category.
What makes you say that over this Monolith? I got curious and went to read the Q350 as a local is selling a single one but I did not get the same positive vibe from that review as I am getting from this one.
Thanks
 

abdo123

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What makes you say that over this Monolith? I got curious and went to read the Q350 as a local is selling a single one but I did not get the same positive vibe from that review as I am getting from this one.
Thanks
it's under the assumption that you will have some sort of Room correction that will put the Q350 to shape. Without room correction the Monoprice is easier to integrate into subwoofers and has a more neutral response.
 
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