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Theory Audio SB25 Speaker System Review

Rate this speaker system:

  • 1. Poor (headless panther)

    Votes: 10 6.4%
  • 2. Not terrible (postman panther)

    Votes: 41 26.3%
  • 3. Fine (happy panther)

    Votes: 92 59.0%
  • 4. Great (golfing panther)

    Votes: 13 8.3%

  • Total voters
    156

amirm

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This is a review and detailed measurements of the Theory Audio SB25 on-wall speaker with its companion 8-channel ALC-1809 amplifier and DSP. It is on kind loan from a member. Speaker costs US $1,095 each and amplifier, US $4,950. Sorry for stock pictures:
Theory Audio SB25 On-wall speaker csd waterfall speaker review front view.jpg

Theory Audio SB25 On-wall speaker csd waterfall speaker review side view.jpg


As you see, this is a very sleek speaker designed to be hung on the wall and comes with nice bracket. Built quality is excellent with the speaker feeling like a rock. Weighs as much too for its size! Unexpectedly for a system speaker, it is driven passively with the crossover being inside the speaker rather than DSP module. On the other hand, this halves the number of amplification channels needed which is a lot in a home theater/surround system:
Theory Audio SB25 On-wall speaker csd waterfall speaker amplifier ALC-1809 review.jpg


Theory Audio SB25 On-wall speaker csd waterfall speaker 8-channel amplifier ALC-1809 review.jpg


Two configuration apps are provided. You can load up different profiles (DSP settings) into the Windows app using either. I opted for the "Flat" (I think version 1.4) profile.

Speaker was measured using Klippel Near-field scanner without taking the grill off. Company seems to have measurements using the same system showing exemplary response:
sb25+v1.6+Frequency+Response.png


Let's measurement ourselves to see if we get the same response.

Theory Audio SB25 Speaker System Measurement
Let's start with our anechoic CEA-2034 series of measurements:
Theory Audio SB25 ALC-1809 Amplifier Flat Response Anechoic CEA2034 Frequency Response Measure...png

Bass response matches company measurements up to about 500 Hz. From there, there are small disturbances likely caused by the port. The treble response starting from 1.5 kHz seems slightly lower which could be intentional or difference in how they measured the speaker and tuned the DSP with it. It is not consequential though as you would want to dial your own in-room response anyway.

Despite the wide waveguide around the tweeter we see some directivity error. This is caused by the dual woofer interference with each other. We see this more clearly in our early window response:
Theory Audio SB25 On-wall speaker early window speaker measurement.png

We will revisit this in our directivity measurements. As noted, thick carpeting and ceiling absorption is advised (or high ceilings). This becomes the only failing in the predicted in-room response:
Theory Audio SB25 On-wall speaker Predicted in-room response speaker measurement.png

And maybe that slight peaking around 4.2 kHz.

I forgot to measure the port response in our near field driver measurement:
Theory Audio SB25 On-wall speaker near-field driver speaker measurement.png


We see the same peaking around 4.2 kHz in tweeter response but otherwise, what we have is unventful.

The company's claim to fame is power handling and high SPL so let's see how it did in distortion department:

Theory Audio SB25 On-wall speaker speaker relative THD Distortion measurement.png

Theory Audio SB25 On-wall speaker speaker THD Distortion measurement.png


Considering how compact this speaker is, this is very good response. Notice how bass distortion never rises to the level of the output. Indeed, during frequency sweeps I was impressed by the clean bass response. Everything has a limit though. Here is 106 dBSPL:
Theory Audio SB25 On-wall speaker speaker relative THD Distortion 106 db measurement.png

Despite how bad this looks, again, bass response was surprisingly clean.

Horizontal directivity is very nice:
Theory Audio SB25 On-wall speaker speaker horizontal beam width measurement.png

Theory Audio SB25 On-wall speaker speaker horizontal directivity measurement.png


Vertical though, is messy as expected with dual woofers:
Theory Audio SB25 On-wall speaker speaker Vertical directivity measurement.png

Dual drivers give you much more power capability but costs you in narrowing the response as the two drivers "beam" together, shrinking usable response to ± 10 degrees. Using it horizontally means narrow coverage unless you sit very far. Be sure to position the speaker in horizontal configuration as to point to listener as to maximize that 20 degrees. Vertically it should be fine but again, position the tweeter toward your ear and don't listen to them standing up! :)

Same resonances that we saw in distortion measurements show up in our waterfall:
Theory Audio SB25 On-wall speaker csd waterfall speaker measurement.png


Finally here is the step response:
Theory Audio SB25 On-wall speaker speaker Step Response measurement.png


I am sorry but I did not get a chance to listen to this speaker, nor measure the amplifier.

Conclusions
While company measurements seem overly optimistic/smoothed, overall performance of SB25 speaker system seems excellent for such a compact and family friendly speaker. The cost is high but I am told prices have increased substantially as of late. I don't have a recommendation for you since I did not get a chance to listen to the speaker but you should have the data to decide whether this system is for you.

As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
 

Attachments

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Reserved for @AdamG to kindly add the specs.

Manufacturer Specifications:

- Theory Audio SB25 on-wall speaker:


IMG_0743.jpeg

IMG_0744.jpeg


- 8-channel ALC-1809 amplifier and DSP
IMG_0745.jpeg

IMG_0746.jpeg
 
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I think they're extremely pricey at $3398/pr, especially when you can get a pair of Neumann KH 150's for $3500 with full amplification and optional DSP for another $300. The Neumann's will outperform these guys in every single way that can be measured, I don't imagine they'll sound worse either.
 
You notice that the average SPL in the plot was ~107 dB and the plot title said at r = 3 m (which mean 116.5 dB @ 1 m)?
I was about to give it great by that alone but then I checked sizes,amp sizes,thermals,specs,etc and it does not seem possible.
So yes,it's a little fishy.
 
You notice that the average SPL in the plot was ~107 dB and the plot title said at r = 3 m (which mean 116.5 dB @ 1 m)?
Just have a look at Amir's measurement at 106 dB: something seems to be wrong with the measurements of the manufacturer.
 
For what it is it measures damn good. Is there any better measuring on wall???
I dont think so.
Not cheap, but it delivers.

Btw, the amp looks tastefull.
All in assuming that you configure all 8 amp channels available were looking at $19,591.00 not including taxes, shipping, insurance. :oops:
 
Why not just get a couple Neumann KH150s and save thou$and$ of dollar$ while getting deeper bass and less distortion?
Because you need something that only sticks out 4" from the wall. Otherwise, I don't think you would get these. For low profile speakers these measure shockingly well, though.
 
All in assuming that you configure all 8 amp channels available were looking at $19,591.00 not including taxes, shipping, insurance. :oops:

Sure but imagine how many "audiophiles" buy cables for that money. ;) Yes its expensive. But it delivers. While expensive cables deliver the same than cheap cables. Would i buy it? No iam not rich enough.
 
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Were they hung on a wall when tested or does the Klippel factor that in its calcs? seems like bass would be lower on a wall?
 
I think the only odd thing about the price is that at this price point most consumers are looking at invisible solutions.

Second thing, they hammered that response into line. I think this is the flattest response I've seen outside Neumann. I wonder if designers like Kali do less correction for some valid acoustic reason or if they are trying to be economical with dsp.

Anyway, nice to see performant and unique products. The price is a trifle to the sort of person who buys these, you know how much it costs to build a new space in a nice neighborhood?
 
At 100dB bass is highly distorted with these speakers. Can't imagine why anyone would want this design. Playing the "Upright Bass Affairs" CD by Hamish Balfour-Paul would likely rattle the speakers right off the wall. It's funny how some will vote in favor of any crazy design when the manufacturer lies about a flat FR response and doesn't mention bass distortion.
 
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