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Ascend Acoustics Horizon Center Speaker Review

amirm

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This is a review and detailed measurements of the Ascend Acoustics Horizon Center speaker with RAAL tweeter upgrade. It costs US $1,495 according to its owner ($350 tweeter upgrade fee).

The Horizon is a heavy beast and seems well finished:

Ascend Acoustics Horizon RAAL tweeter upgrade Audio Review.jpg


It is too heavy for my photo booth so you see it where I put to listen to it. The fabric under it is made out of special material that helps push the electrical energy that would normally be wasted in speaker/crossover wires back into the speaker. I plan to market it as an effective tweak but we digress.

Measurements that you are about to see were performed using the Klippel Near-field Scanner (NFS). This is a robotic measurement system that analyzes the speaker all around and is able (using advanced mathematics and dual scan) to subtract room reflections (so where I measure it doesn't matter). It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise. Both of these factors enable testing in ordinary rooms yet results that can be more accurate than an anechoic chamber. In a nutshell, the measurements show the actual sound coming out of the speaker independent of the room.

I used over 800 measurement point which was enough to compute the sound field of the speaker within 1%error.

Temperature was 77 degrees. Measurement location is at sea level so you compute the pressure.

Measurements are compliant with latest speaker research into what can predict the speaker preference and is standardized in CEA/CTA-2034 ANSI specifications. Likewise listening tests are performed per research that shows mono listening is much more revealing of differences between speakers than stereo or multichannel.

Spinorama Audio Measurements
Acoustic measurements can be grouped in a way that can be perceptually analyzed to determine how good a speaker is and how it can be used in a room. This so called spinorama shows us just about everything we need to know about the speaker with respect to tonality and some flaws:

Ascend Acoustics Horizon RAAL tweeter upgrade Spinorama CEA-2034 Frequency Response Measurement.png


Not too bad! There is a cancellation around 500 Hz and a couple of resonant peaks (where all the curves tilt up together).

Due to inclusion of mid-range, directivity is good which we like to see in a center speaker that has to cover wide listening area in a home theater situation.

Early window graph averages to a good curve but individual reflections do vary a lot:

Ascend Acoustics Horizon RAAL tweeter upgrade Spinorama CEA-2034 Early Window Frequency Respon...png


What this says to me is that the acoustic properties of your room will impact this curve as it modifies reflections differently than our simulated room below.

Putting the two together we get our predicted in-room response:

Ascend Acoustics Horizon RAAL tweeter upgrade Spinorama CEA-2034 Predicted In-room Frequency R...png


The variations we saw in on-axis response mellow out a bit which is good.

Directivity Response
Looking at how sound radiates in different planes, we get this in what we call "beam width:"

Ascend Acoustics Horizon RAAL tweeter upgrade beamwidth Measurement.png


For a center speaker, we want wide beam width as this allows the side reflections to hit the walls and expand the perception of the speaker to be closer to the width of the display. Having 70 degrees here with reasonable flatness helps. Most smaller speakers are around 50 degrees for example.

I have worked on making the 3-D version of the above be easier to interpret. Let me know what you think:

Ascend Acoustics Horizon RAAL tweeter upgrade Horizontal Directivity Measurement.png


An idea response would be a shaft of red color and the smoothly falling into blue. We have a lot of choppiness here but we need to examine more speakers using these settings to get better calibrated.

Here is our vertical response:

Ascend Acoustics Horizon RAAL tweeter upgrade Vertical Directivity Measurement.png


We see that I put the microphone at the center of the tweeter (all the way to the right). I can't figure out why the acoustic center of the mid-range is above that as I have indicated. Anyone has an explanation?

Anyway, vertical directivity gets very narrow around 4 kHz so best to have your ear at the RAAL tweeter center.

Here is our CSD/waterfall:

Ascend Acoustics Horizon RAAL tweeter upgrade CSD Waterfall Measurement.png


Speaker Distortion Measurements
This speaker is too wide for my current deep dive distortion measurements (I am working on fixing that) so we are just going to run with standard response we get out of Klippel system:

Ascend Acoustics Horizon RAAL tweeter upgrade relative distortion Measurement.png


We have a problem around 1 kHz and to some extent, around 3 to 3.5 kHz. We can see the same in absolute levels:

Ascend Acoustics Horizon RAAL tweeter upgrade distortion Measurement.png


Notice that distortion is actually higher than the fundamental tone below 35 Hz. This often happens and it says that what you get will not resembled the original tone. So some filtering of that may be advised.

Impedance and Phase Measurements
This is a low impedance speaker so best to get a capable amplifier to drive it:

Ascend Acoustics Horizon RAAL tweeter upgrade impedance and phase Measurement.png


There are also some "kinks" indicating resonances. I see one around 380 Hz for example.

Speaker Listening Tests
I placed the speaker in my usual spot as you see in the review photo. But due to large width of this speaker, I had to move the stand a bit.

First impression was that "this speaker is alright." Bass was standing out a bit but no way of telling if that was too much or hitting some room mode. Or else, what it should have been producing.

I couldn't put my finger on what was wrong with it other than my excitement level was not at max. Yes, that is a technical term. It is covered under US ISO standard, 23476-A (annex E).

So I went and looked up the measurements which I had created a couple of days before and forgotten by now and corrected a couple of minor things:

Ascend Acoustics Horizon RAAL tweeter upgrade Equalization Roon Fix.png


As usual, ignore the filter at 102 Hz as that deals with a room mode in my listening space that exist with all speakers. The rest are self-explanatory and are based on predicted in-room response. They are "eyeballed" so more precise computation may be better.

The sum total of the speaker corrections improved detailed, gave it a bit more airiness and reduced distortion/accentuation of highs. Not a whole lot bot some amount.

Once there, the Horizon Center was very nice sounding and was capable of playing very loud.

On my deep, deep bass track it would bottom out but do better than that typical bookshelf speaker.

Conclusions
Objectively and subjectively the Ascend Acoustics Center speaker rated well. It is not perfect but gets close enough at the asking price to be fine.

I give it a like but for some reason is not something I would buy. You all decide on your own.

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

Check out small sampling of today's garden harvest:

Garden.jpg


Need money to get some nice meat or fish to go with it! So don't be cheap and
donate what you can using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
 

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MZKM

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No FR measurements for the RAAL upgrade, but here is how it compares to the base model, using their graphs scale:
Screen Shot 2020-08-08 at 4.24.37 PM.png
Screen Shot 2020-08-08 at 4.24.46 PM.png

The hump at ~600Hz and dip at 500Hz & ~1000Hz are more pronounced (I believe these are unsmoothed, no telling what PPO though). I also have no clue how they are measuring bass, it goes deeper than what the NFS is getting, and thus also the specs don't match.
 
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MZKM

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The Horizon is a heavy beast and seems well finished:

index.php
At ~$1500 each I would expect magnetic grilles, they recently added them for their tower speakers. It really lowers the beauty when you take the grilles off. Also not sure why they need 8 holes.

______
Here is our vertical response:

index.php


We see that I put the microphone at the center of the tweeter (all the way to the right). I can't figure out why the acoustic center of the mid-range is above that as I have indicated. Anyone has an explanation?
That is around the crossover region for the dual woofers. Maybe it is some cabinet diffraction up top and that doesn't appear near the bottom due to the ports below each of them (them sucking in some of the off-axis response)?


___________

Speaker Distortion Measurements
This speaker is too wide for my current deep dive distortion measurements (I am working on fixing that) so we are just going to run with standard response we get out of Klippel system:

index.php


We have a problem around 1 kHz and to some extent, around 3 to 3.5 kHz. We can see the same in absolute levels:
Wonder if 1kHz woofer or midwoofer.
As for 3-3.5kHz, I guess that shows again that RAAl tweeters like to be crossed at 4kHz.
 
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amirm

amirm

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Wonder if 1kHz woofer or midwoofer.
Oh, I should have noted that I could not measure the drivers independently. The microphone on NFS rotates around the speaker but can't go side to side so could not capture anything other than tweeter and midrange.
 

Dennis Murphy

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At ~$1500 each I would expect magnetic grilles, they recently added them for their tower speakers. It really lowers the beauty when you take the grilles off. Also not sure why they need 8 holes.

______

That is around the crossover region for the dual woofers. Maybe it is some cabinet diffraction up top and that doesn't appear near the bottom due to the ports below each of them (them sucking in some of the off-axis response)?


___________


Wonder if 1kHz woofer or midwoofer.
As for 3-3.5kHz, I guess that shows again that RAAl tweeters like to be crossed at 4kHz.
You can't generalize about RAAL tweeters. The Horizon uses the OEM 70-20, which is actually designed to be crossed around 2 kHz, unlike the 64-10X used on the Sierra 2 series and my BMR, which needs a crossover point at least 1 kHz higher. From the vertical directivity plots, it looks like the 70-20 is being crossed around 2500 Hz (Dave would have to confirm), which is quite conservative for this unit. In any event, 1.5% maximum THD at 96 dB is an excellent figure for a ribbon and not of any audible consequence that I can imagine at this SPL.
 

617

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Horizontally oriented center speakers are hard to design and this one seems pretty good.
 

MZKM

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it looks like the 70-20 is being crossed around 2500 Hz (Dave would have to confirm), which is quite conservative for this unit. In any event, 1.5% maximum THD at 96 dB is an excellent figure for a ribbon and not of any audible consequence that I can imagine at this SPL.
Looking at the directivity index, I would have said ~3500Hz.
I doubt I could hear that distortion, but I would prefer no higher than 1%.
 

Cahudson42

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The fabric under it is made out of special material that helps push the electrical energy that would normally be wasted in speaker/crossover wires back into the speaker. I

Bundle with some Connector Tubes to further reduce all the losses that would usually occur through the binding posts and get the additional benefits of even fuller, more robust, deeper and lower bass!
 
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amirm

amirm

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Bundle with some Connector Tubes to further reduce all the losses that would usually occur through the binding posts and get the additional benefits of even fuller, more robust, deeper and lower bass!
I tried that. The micro detail was all wrong. You have to pay attention to "synergy" there!
 

Xyrium

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Crazy distortion below 35Hz...expected, but is that perhaps just below the port tuning frequency?
 

Dennis Murphy

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Looking at the directivity index, I would have said ~3500Hz.
I doubt I could hear that distortion, but I would prefer no higher than 1%.
Could be, although that would be the highest I've seen for this tweeter, and the very broad beamwidth at 3 kHz seems inconsistent with the likely midrange dispersion, but Dave can educate us.
 

astr0b0y

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Thanks @amirm for the review and for whoever sent this in. I imported one of these and a pair of Sierra-2's about 6 years ago. Have been very happy with them as the LCR in my system (powered by a Rotel 5-channel power amp).
Here's the supplied FR measurements from my unit.

HORIZON.png
 

BYRTT

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.....We see that I put the microphone at the center of the tweeter (all the way to the right). I can't figure out why the acoustic center of the mid-range is above that as I have indicated. Anyone has an explanation?.....

Best guess is 1) below mid-range there's no baffle reflection, then this one 2) summing to woofers happen a squize above mid-range position and it looks in mine CAD exercise that XO region there is at 500Hz, then the aaaaahh 3) could port noise interfere here ? 4) or that special material fabric that probably then will get a patent or some ISO norm down the road :p..

EDIT and great thanks the review..

Vertical_nonsymetry_4x1x_400mS.gif
 
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daftcombo

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Notice that distortion is actually higher than the fundamental tone below 35 Hz. This often happens and it says that what you get will not resembled the original tone. So some filtering of that may be advised.
Did you try a high-pass filter to solve that?
 
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