Polk Reserve R350 Review (Center Speaker)

[amirm]

Given the universal acclaim of the A130, maybe the A135C are worth a shot - or a test

Crutchfield has them for $179. One of you should buy and send it to me for testing.

 

[MZKM]

So... if I bought a pair of these and mounted to each side of the TV in an upright position (so it's taller than wider) connected in series, I'd benefit from their very good vertical directivity converted to horizontal and all would be well, right?
and .. the same would apply to something like the JBL Stage A135C (also very slim, just 10cm), since it has the same design, but it's significantly cheaper. Given the universal acclaim of the A130, maybe the A135C are worth a shot - or a test.

Preference Rating (L/R)
Score: 3.9
SCORE w/ sub: 6.6

 

[notabenem]

So... if I bought a pair of these and mounted to each side of the TV in an upright position (so it's taller than wider) connected in series, I'd benefit from their very good vertical directivity converted to horizontal and all would be well, right?

Unless, since there are 2 of them approx 1m apart, they will cancel each other out at certain positions as the following Octave simulation shows:

# at 1Khz and 20C
wavelength=0.343;
speakerDistance = 1;
[x,y]=meshgrid(-2:0.03:3,0:0.03:5);
sinA = sin(sqrt(x.^2+y.^2)/wavelength*2*pi);
sinB = sin(sqrt((x-speakerDistance).^2.+y.^2)/wavelength*2*pi);
sc = surfc(x, y, sinA+sinB);
shading interp
colormap jet

 

[notabenem]

Thinking about it, the cancellation must be very very theoretical.
It does not include facts like 2 listening position (2 ears 20cm apart), all kinds of reflections and other stuff... If it was like this, this would be very audible in any stereo setup... Or?

 

[Matt0305]

Thank you for taking the time to review this center channel speaker! I was considering it in combination with the R600 tower's as a compromise with my wife as they will be in our in our living/media room. I need a center under 7 inches tall to fit into her plans, and the off axis response just ruled this one out. I wonder if the R300 will fare better with it's more conventional MTM design.

 

[notabenem]

Preference Rating (L/R)
Score: 3.9
SCORE w/ sub: 6.6

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Thanks! But not sure how to interpret this (except better horizontal directivity).
Is this showing 4 woofers and 2 tweeters in their exact physical positions when the speaker(s) are rotated 90 degrees and 1m apart?

 

[Ata]

There is much to be said about using an inexpensive small coax speaker like the KEF Q150 as a centre speaker. Crossed over at 100Hz with a sub, there is good directivity and bass. While the raw FR may be a bit uneven (it has not been measured here but Q350 looks alright), much of it can be corrected either manually or via Audyssey/Dirac/etc. SPL should not be a problem unless you are in a very large room.

I went down this path as a temporary solution, but it is so good I find it hard to justify spending over a grand to get further improvement, and KEF R2c has its own share of issues... I can only see myself upgrading to identical LCRs at some point in the future, when/if I get much bigger space to work with.

 

[PeteL]

I know these are not flagship but why deseign a 4 mid/woofer 2 way that is known to make it garbage when the cheaper model with 2 mid/woofer should have much better performance if all things are equal.

But all things will not be equal, they won't play as loud.

 

[Gorgonzola]

As Amir says, the narrow horizontal dispersion defeats the purpose of a center channel speaker -- hence I voted 'headless panther'.

Quite a few years ago I build a DIY center channel that I'm still using today. It has one mid-bass and one port to either side of the tweeter. I wish Amir could test it to see how it would fair.

 

[mhardy6647]

Yeah, but, Matthew Polk is retired (at least from his eponymous loudspeaker company), puttering with interesting things (it is said) and living on Gibson Island in Maryland (according to his LinkedIn profile).

I know that the XOs in the "L" and "R" series Polks are rather complex -- I wonder if the two pairs of, aaaaahh, woofers in this R350 are simply paralleled with each other, or if the implementation is more, shall we say, nuanced? If the former, it might be... edifying... simply to disconnect half of each pair (e.g., the outboard drivers) and see if the dispersion anomalies would be vanquished.

(note my liberal use of the subjunctive in the last sentence above -- though if they were mine, I'd be whippin' out an appropriate screwdriver and seeing what's what behind the baffle)

 

[MZKM]

Thanks! But not sure how to interpret this (except better horizontal directivity).
Is this showing 4 woofers and 2 tweeters in their exact physical positions when the speaker(s) are rotated 90 degrees and 1m apart?

It’s simply if you stood it upright.

You can see that the listening window is now much similar to the on-axis, so seat to seat consistency is much better.

 

[beagleman]

Apparently nobody at Polk listened to this thing before it went on sale, not to mention measure it ...

I can tell you for SURE, that is not so. They have a whole team of Engineers that do EACH speaker and crossover, and it is extensively tested.

This may fall under the category of marketing or this is how they wanted it to sound or seem, but for sure there was lots of research and listening and measuring.

 

[PeteL]

I've always wanted to ask. Is there any inferior aspect of coaxial designs (barring R&D cost of getting it performing properly/and of course the lesser power output I suppose) compared to multi-driver designs? We've seen Genelec demonstrate how superior their designs are... I'm just not understanding why doesn't every company offer a design like this? Or in the case of virtually every other instance of industry - whenever a newer more superior standard arises, the old one is slowly phased out entirely eventually. So what's the hold up?

You are barring one of the most important reason tough. R&D is expensive. I am speculating here but there may be some patented elements in the best performing ones. Also major speaker manufacturers may take a real hit on prestige if they start using OEM drivers and there is an increase in cost in doing so too, and that's IF those who have the tech are even willing to go OEM, that's not necessarily smart. Kef have had some form of Coax for decades, this has not been universally recognised that speakers using coax are necessarily better every time. Lastly, it's not factual that superior tech always win and less performing ones dies. There are plenty of counter examples, market adoption is not as simple as that.

 

[testp]

Marketing

why is marketing medlying with engineering in the first place?!? Do your business where you suppose to, not interfere with other department know-how...

 

[PeteL]

why is marketing medlying with engineering in the first place?!? Do your business where you suppose to, not interfere with other department know-how...

They are not designing, we can put that to rest, but market study is key in specifying the scope of a project. Price point, form factor, target audience, etc

 

[beaRA]

why is marketing medlying with engineering in the first place?!? Do your business where you suppose to, not interfere with other department know-how...

Nothing about this situation should be bewildering. The marketing team identified a niche of customers willing to buy passive speakers if the center channel fit in a soundbar form factor to be easily mounted under a TV. The engineering team designed within those constraints. Polk makes more traditional MTM centers in the same line and a 3-way in their flagship line for those of us that care more about dispersion performance than space/aesthetics.

 

[PeteL]

They would make a good front speaker, but why would this form factor even be considered for surrounds?

Edit: it may be the mounting brackets attracting a factor of convenience.

Polk don't sell these as center only, they are sold as LCR. I can see people with small room have one of those mounted vertically on Each side of the screen, bracketed to the wall. very unobtrusive, interior design and the way people live is also key in putting out a product, not only the technical aspect. I am sure for many families this sounds good enough.

 

[sarumbear]

I am shocked to see how many people are rating this speaker less than "fine", despite Amir's positive impressions from his listening position:

I’m shocked that you are that selfish and that you don’t care if your other half or friends hear bad sound.

 

[Deleted member 28042]

This speaker seems to have problems in a large part of the frequency range (500Hz through 2Khz) that directly affects dialogue intelligibility. That seems like exactly the opposite of what you would want in a center channel.

 

[sarumbear]