This is a review and detailed measurements of the Ascend Sierra Luna small bookshelf 2-way speaker. It was kindly sent in by a member. The Luna costs US $588 each or US $1,148 for a pair.
The Luna is one of the smallest speakers I have measured:
Despite its small size, it is a very dense and heavy speaker. As you see it is front ported.
The back panel shows nicely machined in provisions for wall mounting which should come in handy for home theater Atmos (height) speakers and such:
The label says it is designed, engineered, and assembled in US. Does it mean it is manufactured fully in US? Or do they get the boxes from overseas and put the parts in it in US?
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 performed over 800 measurement which resulted in error rate of less than 1% throughout the range.
Temperature was 61 degrees F. 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.
Reference axis was the tweeter center.
Ascend Sierra Luna 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:
OK, this is a very jarring response. A woofer doesn't dance up and down so sharply by itself in a few hundred hertz? Fortunately I measure each driver at point blank and this tells us the problem:
See the port response in orange? It peaks (resonates) so much that its response actually exceeds that of the woofer creating those two "horns." It continues to mess up the woofer response even past that.
Strange to see the woofer response flattening post crossover point. Maybe it was also resonating? Regardless, if that was pulled down more , the combined response with tweeter would have been better.
Back to the spinorama, note that the efficiency to a few hundred hertz is only 80 dB or so. Indeed, I had to boost the signal by 6 dB compared to average of what I use for most speakers to get to 86 dBSPL output. Better have a lot of amplifier power. Don't be fooled by the small size of this speaker.
Early window response shows the same problems we see on-axis since port response is more or less omnidirectional:
Combined we get what dominates the on-axis:
Impedance is good bit higher than what is typical for 2-way speakers:
Resonaces are visible by the way in kinks in the impedance graph (little ripples).
Distortion is naturally high at levels exceeding 86 dBSPL but I was surprised the speaker did not bottom out:
A highlight is the horizontal beamwidth:
Because the woofer is not much larger than the tweeter, their beamwidths blend together much better than in larger configurations.
Vertically is a mess as it typically is:
Makes sure your ears are more or less at the height of the tweeter.
Ascend Sierra Luna Speaker Listening Tests
I tell you, marketing guys are right that the first impressions of a bright speaker are positive. Such was the case during the first few seconds: "oh listen to the details!" This changed though after a minute or so to: "man this is bright!" The sound was lispy as well but not super annoying. Just bright. So I pulled out the EQ:
Despite the aggressive shelving filters I put in for high frequencies, the outcome was still a bit too bright but much more manageable.
Fixing the two port created resonances only made a subtle difference -- certainly less than what jumps out in the frequency response graph. A more accurate EQ may generate better outcome though than my eyeballing.
On a positive front, this speaker can handle a ton of power and get quite loud! Lack of bass response means that the little woofer does not bottom out -- not easily anyway. I was pretty impressed by this and should make the speaker more suitable for home theater applications.
Conclusions
Despite being very small, the Luna seems well built. Alas, poor port response wreaks havoc on the bass response. And elevated tweeter response makes the overall response too bright. Directivity is generally good so EQ seems to work well. Power handling is excellent due to not attempting to change the laws of physics and generate more bass than it is capable of.
As a perfectionist of course I want to see near ruler flat on-axis response at these prices. We don't have that here so score should be way down. I am not going to absolute bottom though as I hate distortion and lack of power handling in small speakers which the Luan does not suffer from.
Overall, I can't recommend the Ascend Sierra Luna but put it out there for people to optimize it with EQ to get respectable sound.
------------
As always, questions, comments, recommendations, etc. are welcome.
We are fortunate to live in a place where wild chanterelle mushrooms grow abundantly. My wife bought a basket recently:
Made a Chinese vegetarian stir-fry using our garden peppers and they were delectable! There is a farm near us where they would actually pick them but they had a ton of pine needles in them which made a pain to clean. The above were almost free of them which was great.
As always appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
The Luna is one of the smallest speakers I have measured:
Despite its small size, it is a very dense and heavy speaker. As you see it is front ported.
The back panel shows nicely machined in provisions for wall mounting which should come in handy for home theater Atmos (height) speakers and such:
The label says it is designed, engineered, and assembled in US. Does it mean it is manufactured fully in US? Or do they get the boxes from overseas and put the parts in it in US?
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 performed over 800 measurement which resulted in error rate of less than 1% throughout the range.
Temperature was 61 degrees F. 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.
Reference axis was the tweeter center.
Ascend Sierra Luna 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:
OK, this is a very jarring response. A woofer doesn't dance up and down so sharply by itself in a few hundred hertz? Fortunately I measure each driver at point blank and this tells us the problem:
See the port response in orange? It peaks (resonates) so much that its response actually exceeds that of the woofer creating those two "horns." It continues to mess up the woofer response even past that.
Strange to see the woofer response flattening post crossover point. Maybe it was also resonating? Regardless, if that was pulled down more , the combined response with tweeter would have been better.
Back to the spinorama, note that the efficiency to a few hundred hertz is only 80 dB or so. Indeed, I had to boost the signal by 6 dB compared to average of what I use for most speakers to get to 86 dBSPL output. Better have a lot of amplifier power. Don't be fooled by the small size of this speaker.
Early window response shows the same problems we see on-axis since port response is more or less omnidirectional:
Combined we get what dominates the on-axis:
Impedance is good bit higher than what is typical for 2-way speakers:
Resonaces are visible by the way in kinks in the impedance graph (little ripples).
Distortion is naturally high at levels exceeding 86 dBSPL but I was surprised the speaker did not bottom out:
A highlight is the horizontal beamwidth:
Because the woofer is not much larger than the tweeter, their beamwidths blend together much better than in larger configurations.
Vertically is a mess as it typically is:
Makes sure your ears are more or less at the height of the tweeter.
Ascend Sierra Luna Speaker Listening Tests
I tell you, marketing guys are right that the first impressions of a bright speaker are positive. Such was the case during the first few seconds: "oh listen to the details!" This changed though after a minute or so to: "man this is bright!" The sound was lispy as well but not super annoying. Just bright. So I pulled out the EQ:
Despite the aggressive shelving filters I put in for high frequencies, the outcome was still a bit too bright but much more manageable.
Fixing the two port created resonances only made a subtle difference -- certainly less than what jumps out in the frequency response graph. A more accurate EQ may generate better outcome though than my eyeballing.
On a positive front, this speaker can handle a ton of power and get quite loud! Lack of bass response means that the little woofer does not bottom out -- not easily anyway. I was pretty impressed by this and should make the speaker more suitable for home theater applications.
Conclusions
Despite being very small, the Luna seems well built. Alas, poor port response wreaks havoc on the bass response. And elevated tweeter response makes the overall response too bright. Directivity is generally good so EQ seems to work well. Power handling is excellent due to not attempting to change the laws of physics and generate more bass than it is capable of.
As a perfectionist of course I want to see near ruler flat on-axis response at these prices. We don't have that here so score should be way down. I am not going to absolute bottom though as I hate distortion and lack of power handling in small speakers which the Luan does not suffer from.
Overall, I can't recommend the Ascend Sierra Luna but put it out there for people to optimize it with EQ to get respectable sound.
------------
As always, questions, comments, recommendations, etc. are welcome.
We are fortunate to live in a place where wild chanterelle mushrooms grow abundantly. My wife bought a basket recently:
Made a Chinese vegetarian stir-fry using our garden peppers and they were delectable! There is a farm near us where they would actually pick them but they had a ton of pine needles in them which made a pain to clean. The above were almost free of them which was great.
As always appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/