This is a review, listening tests, EQ and detailed measurements of the Ascend Acoustics Sierra-1 V2 bookshelf speaker. It is on kind loan from a member and costs US $998 for a
pair ($948 on sale).
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The finish is nice enough. The cabinet feels quite heavy for its size and especially in the front indicating beefy low frequency woofer. I do wish the grill was magnetic though rather than plastic tabs that are more delicate. I did my testing without it and would have been nice to not see those holes.
Back panel put a big smile on my face:
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See the "NFS Optimized" tag! A couple of years ago I tested an Ascend speaker and found the performance wanting. Needless to say, the company owner/designer, Dave, was not happy. But instead of taking his anger on me, he reached out to Klippel to learn more about the Near-field Scanner I had used to test his speaker. He quickly ordered one and started to revamp his speaker designs. We have seen an example of this in electronics area and benefits it brings to the company and its buyers. Such is happening here in speaker design.
It was with nervous fingers and ears that I went into this testing. Yes, there is another set of measurements out there but my testing differs enough to merit testing a user purchased sample. So here we go.
FYI, I ran the measurements by Dave (company designer) last night and they correlate very well with their internal measurements. There is a tiny bit of deviation in bass well below response of the speaker which is not material. And at any rate, I measured the speaker at 59 degrees F which tens to damp bass response a bit.
If you are not familiar with the measurements you are about to see, I highly recommend you watch my video on
understanding speaker measurements:
Ascend Sierra-1 V2 Speaker Measurements
Let's start with our speaker frequency response measurements as usual:
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On axis response is quite good with only small variations here and there which my higher resolution scan brings out more than other measurements. We see a couple of small resonances below 1000 Hz (see below for cause). And a dip around 3 kHz. But really, these are very minor. What is very remarkable is the early window response in dashed blue. It is so smooth and nice after 900 Hz. We can see that in detail in early window response:
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This is what you get with closed loop measurements and excellent engineering folks! All the reflections so nicely sum together, likely better than any speaker I have measured! This means the speaker will be very room friendly and easy to place. To wit, putting everything together we get an excellent predicted in-room response:
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Amazing that this is achieved in a passive speaker without DSP!
Close-in measurements of the port and driver show resonances very well suppressed:
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Putting on our hyper scrutiny hat, we do see minor contributions from the port resonances in on-axis response. But as judgements go against countless other bookshelf speakers, this is excellent showing.
Sensitivity of the speaker is low side to get that deeper, flat extended response and that brings out issues with the woofer not being able to handle high SPL very gracefully:
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But keep that thought when I evaluate this in listening tests.
I showed this tri-power sweep in the last speaker review and folks liked it so I repeated it here. Alas, 102 dBSPL was causing the speaker to nearly blow its mind so it is well outside of its design envelop:
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The difference between 86 and 96 is too minor to be of concern.
Horizontal directivity is fairly well control especially considering that we don't have a deep waveguide:
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The lack of waveguide is what allows the wider directivity which again, I will evaluate in listening tests.
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Vertical directivity has the typical issues we see in non-coaxial designs so nothing of specific worry here:
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Impedance is unusually high in this day and age, making the speaker an easier drive although lack of sensitivity means you still need lot of power on tap:
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Here is our waterfall and step responses:
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Ascend Sierra-1 V2 Listening Tests and Equalization
As I noted at the outset, I was a bit nervous about going into this aspect of the listening test. Would I like a speaker that is fully optimized with NFS in listening tests? Would I be biased to like it regardless? I always start with my female tracks and here, the response left no room for complaining. Sound was balanced with no aspect of the speaker standing out until a bass note activated a room mode which I corrected with my usual 105 Hz filter. I then listened some more. Am I liking this sound? Answer was, that it was pleasant but not exciting. Measurements showed that speaker was optimized for off-axis and PIR more than on-axis. Let's see what happens when we reverse this situation and flatten on-axis:
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I started with Band 2, filling that small bass dip. That very nicely brought female vocals forward. That encouraged me to then pull down the two port resonances. Yes, the filter strength is very low but it was enough to change the character of the upper bass. Once all the filters were in place, I performed AB tests and boy, I really, really liked the results with this EQ. We are talking about subtle differences but the sound was more open and clarity was improved.
What was really nice was the spatial qualities of the speaker. Its wide directivity meant it projected a large halo around the single speaker I was listening to. This, combined with the tiny tweaks above made for stunning presentation at times. Some of my reference tracks sounded so good that my jaw fell on the floor!
I was expecting to hear distortion at elevated volumes but this did not materialize. Even at elevated playback levels where I could see the woofer moving back and forth, I could not detect any degradation.
The problem area with respect to distortion is in deep sub-bass region. Most bookshelves won't bother to play this range. The Sierra-1 V2 doesn't shy away and attempts to play them at full amplitude resulting in fair amount of distortion. Fortunately this only shows up in my "speaker killer" tracks. On all others, even deep bass was reproduced exceptionally well.
Conclusions
When I was offered this speaker for review at first I thought, well it was measured and tested elsewhere so maybe I need to pass. I am glad I did not and performed the review. We got to test a random production sample and managed to extract some other insights about the speaker. In a nutshell, the design is heavily optimized for off-axis and predicted in-room response which makes the speaker very room friendly and is critical in listener preference studies. The on-axis response which while excellent in this product class, shows a bit of variations. My informal testing shows that slight corrections to response yields subjective improvements in listening. Whether this translates to others or not, I can't say.
The high level picture is that company has made an incredible investment in instrumentation and optimization of its product and it shows. Likely ton of effort has gone into scan after scan to produce some of the best measurements I have seen. Having a Klippel NFS is one thing. Putting up with multi-hour scans for every test iteration is another.
It is my pleasure to add the Ascend Acoustics Sierra-1 V2 speaker to my recommended list.
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