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Ascend Sierra Luna Mini-Monitor Review

MZKM

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Ericglo

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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?


From their site:


I have no clue, but I would have assumed using FEA would have shown the port issues (turbulent air flow?).

The owner of Ascend posted on AVS IIRC in the Philharmonic thread. Again IIRC he said that the cabinets are made in the US. The speakers are then assembled. I believe all of this is done at one location in Southern Cal.

http://www.ascendacoustics.com/pages/about/firsttime.html
 

Ricardojoa

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The 2EX has decent measurements, amazing for them to publish the Spinorama. Would love to see a Spin of the ~$2900 towers w/RAAL.

EDIT: Noticed the 2EX Spin uses a 60dB window, whereas the standard calls for 50dB, so it looks a bit more linear.

______



From their site:


I have no clue, but I would have assumed using FEA would have shown the port issues (turbulent air flow?).
I think amir did the AA sierra center which i believe is identical to the towers except the drivers orientation.
 

Steve Dallas

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Yikes. Another data point for, "If you are planning to spend a decent amount of money, just buy Revels."
 

Shazb0t

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Those are bad measurements. So far Ascend has not lived up to the hype. I seriously considered a pair of these, I am glad I never purchased them.
I think that the Horizon Center RAAL speaker measured quite well and I'd be willing to extrapolate that over to the near identical towers. If the Sierra-2EX spin is to be believed, it also looks to be a great value.

Horizon review:
https://www.audiosciencereview.com/...coustics-horizon-center-speaker-review.15199/

Sierra-2EX spinorama:
SPIN.gif


These Lunas are very small surround speakers. The measurements aren't entirely surprising IMO.
 

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At this price point, I’d go for pro active monitors. There are many good options.

I’m not sure what they mean by “Reference Quality Mini Monitor”... Must be a joke, lol...
 

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Those are bad measurements. So far Ascend has not lived up to the hype. I seriously considered a pair of these, I am glad I never purchased them.

It seems like the models using the 64-10 RAAL all have quite a few problems and an odd response that is elevated after 5k, which is going to sound bright to most people. The Horizon measurement with the 70-20 is much better though and I would expect the Towers with the RAAL to measure as good or better than the center. As good as the 70-20 models measure, my problem with them is that you can get an equally smooth response with a dome tweeter, there is nothing in the measurements that justifies paying that much for the ribbon.

The most interesting thing to me about the reviews of speakers with the raal ribbon is the Amir has never mentioned anything to suggest that there is a quality about them that the frequency response can't explain. Many people who own similar speakers like to talk about how "fast" the transient response is and that the frequency response only partially explains their sound quality. Dr. Toole has mentioned his blind testing with other massless ribbons of the time and noted that frequency response was king and no superiority of ribbons was noted. It seems that Amir's reviews of the various raal model is confirming Dr. Toole's research that the CTA-2034 graph can completely describe the sound quality of a speaker.
 
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Shazb0t

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It seems like the models using the 64-10 RAAL all have quite a few problems and an odd response that is elevated after 5k, which is going to sound bright to most people. The Horizon measurement with the 70-20 is much better though and I would expect the Towers with the RAAL to measure as good or better than the center. As good as the 70-20 models measure, my problem with them is that you can an equally smooth response with a dome tweeter, there is nothing in the measurements that justifies paying that much for the ribbon.

The most interesting thing to me about the reviews of speakers with the raal ribbon is the Amir has never mentioned anything to suggest that there is a quality about them that the frequency response can't explain. Many people who own similar speakers like to talk about how "fast" the transient response is and that the frequency response only partially explains their sound quality. Dr. Toole has mentioned his blind testing with other massless ribbons of the time and noted that frequency response was king and no superiority of ribbons was noted. It seems that Amir's reviews of the various raal model is confirming Dr. Toole's research that the CTA-2034 graph can completely describe the sound quality of a speaker.
The 70-20 RAAL appears to have high power handling, low distortion, extended smooth frequency response (moreso than typical metal domes), and comparable horizontal directivity to a good dome tweeter. Similar attributes that many manufacturers are pursuing with Beryllium domes. Seems a fine choice to me.
 

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Preference score of 1.3, ouch. So much for the halo over this internet direct manufacturer. Thank you for another detailed review @amirm.
 

CDMC

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It seems like the models using the 64-10 RAAL all have quite a few problems and an odd response that is elevated after 5k, which is going to sound bright to most people. The Horizon measurement with the 70-20 is much better though and I would expect the Towers with the RAAL to measure as good or better than the center. As good as the 70-20 models measure, my problem with them is that you can get an equally smooth response with a dome tweeter, there is nothing in the measurements that justifies paying that much for the ribbon.

Dennis Murphy has mentioned that the 64-10 does not work well in a 2 way design. Because of it's small size, it has to be crossed over very high and results in directivity mismatches and has issues with woofer matching as the woofer gets close to it is breakup. Here are some comments on the AVS thread about going to the Aurum Cantus in the new Mini Monitor:

"Please note that the tweeter in this mini isn't the same as the one in the actual production version. This one has the usual suspect RAAL, and the real one will have an Aurum Cantus AMT driver that can be crossed lower."​
In response to the question: "Hey Dennis how does that Aurum Cantus AMT driver compare to Raal?"

"One doesn't dominate over the other. For a 3-way intended for far field listening, I would go with the RAAL because of its superior horizontal dispersion. But for a 2-way, particularly one that will often be used nearfield, I prefer the AC because it can be crossed lower with less distortion. The AC version of the mini has a little more clarity in the lower treble, and that's more important in this application than a very wide and deep soundstage from, say, a 10 - 12ft listening distance. They're identically priced, so that wasn't a factor."​
"I don't have the Zaph mini's here, so I'm just relying on distant memory. First off, the SB Ceramic woofer dominates the Zaph. It goes way lower, is actually smoother than the Zaph. They both have fairly severe breakup modes up high, but that's not a problem with 4th order crossovers. (I only use 2nd order on the BMR, and then just for the woofer-mid cross) The Zaph was crossed a hair under 3500 Hz, which means the Zaph woofer will be into beaming mode at that point. The SB-AC Mini is crossed at 2,400 Hz, which provides more even radiation over the crossover region and a more clean and focused upper midrange and lower treble. The AC AMT doesn't provide as much air as the RAAL at the very top, but the AC is still quite good in that department and has the same sonic signature--less sssssssssssssssss than a typical dome and more natural on cymbals and triangles. As much as I like the RAAL 64-10X, there's no way to avoid a slightly cloudy lower treble in a 2-way design. And believe me, I've heard them all."​

I think I need to see how long Amir's cue is and send him one of my Mini Monitors. Dennis measurements look pretty impressive:

http://www.philharmonicaudio.com/Measurements.html
 
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CDMC

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The 2EX has decent measurements, amazing for them to publish the Spinorama. Would love to see a Spin of the ~$2900 towers w/RAAL.

EDIT: Noticed the 2EX Spin uses a 60dB window, whereas the standard calls for 50dB, so it looks a bit more linear.

Sadly, the measurements posted by them do not seem to match well to the actual measurements. Given the Luna's were supposedly developed over a year and the bass driver was supposedly custom from SEAS they had to be aware of these issues. Here are some of Dave's posts over nearly a year of the "development":

"Spent much of the weekend developing the preliminary crossover which then allows me to truly listen to the Sierra Sat. I was hoping for a less complex crossover than the Sierra-2, but at this point, that doesn't seem like it will be possible.​
As it stands right now, the speaker measures well with fantastic transient accuracy and really unbelievable horizontal off-axis dispersion, thanks in part to the very narrow cabinet and smaller woofer. To get the needed warmth, efficiency will come in at an honest 84-84.5dB anechoic. Phase integration between the drivers is terrific and the speaker can easily be used as close to a listener's ear as they like -- even 6 inches away. Nominal impedance is a very easy 8ohm load with benign phase angles. No doubt the speaker will like some power, and power handling is excellent. I ran a single sat full range with deep bass tracks and hit 93dB at 12 feet back in a very well damped room. Our own HTM-200SE could not keep up with this. Crossed at 80Hz in a typical room, max spl is going to be crazy for a speaker this size.​
Listening....​
I expected to listen for an hour or two last night, and that session ended up being over 4 hours long and set me behind in half a dozen other tasks. Not a problem though as I left the office with a HUGE smile on my face
smile.png
Since the start, I have been concerned if this would end up being a product we can actually sell. No doubt, it is going to be an expensive speaker - basically the same component costs as the Sierra-2. We have already invested a lot of time and expense into the Sat and last night was the time for me to make the call to either push forward or hang it up. Well, the good news is that was a very easy decision to make - the SAT was literally addicting to listen to. It is basically a Sierra-2 without that same level of dynamics and deep bass.​
When we were investigating other high performance speakers similar to this size, I used our HTM-200SE as the benchmark and after every comparison, I came away much preferring our 200. In fact, I would say our 200's flat out crushed the competition in every performance category. In comparing the SSR (sierra sat ribbon) to the 200, the SSR crushed the 200 in every performance category, even in bass, which is something I had hoped for but didn't actually expect. Run full range, bass response comes in at somewhere between the 170 and 200. It is a bit shocking to hear some deep bass from a speaker this size but this amazing woofer combined with the complex porting worked perfectly.​
Compared directly to its big brother, it is a perfect timbre match. The SSR won't measure quite as flat as the Sierra-2, but that is not the goal for this speaker. I am actually really excited to have a listen once again as the detail, musicality, unbelievable transparency (the speaker completely disappears) and the overall amount of sound coming from this little box is shocking...​
All that said, we are not there just yet... From here I have to optimize the crossover and then figure out some way to fit the components onto a PCB that can actually fit into the cabinet. That is going to be a challenge as there is very little room in there.​
Here is a pic from late last night... Maybe I will do a boom boom pow video again, lol."​
Another post:

"The woofer we will be using in the Sat is exceptional and I am not sure if a better one even exists for this purpose. The moving mass of this 4.5" will actually be less than that of the dedicated mid in the tower - while still providing surprising bass extension. This little woofer basically uses the same magnet size as the woofer in the Sierra-2, and by going with a custom Curv woofer cone, we further lower the moving mass (by nearly 2 grams!) yet improve internal damping, and there is almost no cone breakup modes. The motor force is ridiculous for this size woofer, thus transients are exceptional.​
As an example, like with the 6" in the Sierra-2, this 4.5" has lower moving mass than any of the 4.5" EXCEL woofers and even the 4" Scan woofers.​
This woofer, being significantly smaller than the Sierra-2, is actually going to cost us the same $$ amount per unit as the S2 woofer. This woofer is really the key to make this speaker happen and in no way does this woofer choice have anything to do with trying to reach a specific price point. I have actually been evaluating several lower cost woofers in an attempt to lower manufacturing costs, but each one presents a compromise. Either we lose bass extension, such that would require a 100 or 120Hz crossover, or we lose midrange performance, or we lose significant efficiency.​
While I fully understand the continuous hunt for something better, I myself am plagued with this disease, we can likely only slightly improve one parameter of this woofer, while actually hurting other equally significant performance parameters. I simply and honestly can't find anything better for this application, which is precisely why we are going custom made.​
I think you will find the mids on this speaker to be shockingly good...."​

Another:

"I am hoping to receive the final prototype woofer next week, as well as the final crossover sample by June 10th. If both of these items have my approval, we will start production. Once in production, I would estimate 8-10 weeks before we can start shipping. Please understand I really hate giving estimated time frames as I think this somewhat, subconsciously, pushes me to release a product sooner than I am comfortable with - something we have never done and never will"​

And another:

"Been a rough day at the office today...​
Having said that, I received some good news today from SEAS's chief engineer Håvard. Another set of sample woofers are now ready and with these, as mentioned previously - we went with a newly formulated higher loss natural rubber surround combined with a cone that uses a combination of a low compliant weave with a higher compliant weave for the dust cap. The initial test results that have been sent to me are perfect - even better than both I and Håvard had expected.​
This performance report shows even better performance compared to the initial samples sent to me, for which I designed the Luna around, and which we were just trying to match since SEAS had changed surround vendors since the original samples were made.​
Of course, I still need to test them and I am generally more critical than SEAS is - but according to the tests they took - the issue I was having with the samples, even testing many various iterations of surrounds from this new vendor, has been completely resolved, not only resolved - but even better now. I have literally lost count of how many samples we have gone though...​
These will be on their way to me by air tomorrow and I should have them sometime next week. If all goes well, and I now fully suspect it will - purchase orders will be placed for all Luna components within 2 weeks. I honestly don't have an estimated release date - assuming this version of the woofer is perfect, based on experience, I would guess 2 1/2 - 3 months, possibly slightly sooner or it could be longer.​
This has been challenging, frustrating and exhausting and I was getting close to shutting this project down and refocusing our resources. However, we will soon have another speaker in our Sierra line that is going to be unmatched and a true engineering feat, possibly even my proudest, in the sense of achieving this level of performance in a speaker this small and what we had to go through to get there.​
Like all of our products, there is not a single component in the Luna that is not fully custom to us. In fact, for this woofer - both the cone, surround, former and voice coil have been custom designed for us by both Håvard and little old me (and I stress old)​
Fingers are crossed but I am fully confident we are finally there!!​
Also hope to have the final prototype pair completed by the end of next week - so if anyone local to us wants to come have a listen, just let me know..."​

And the final design:

"I typed up my scribble notes for my listening session last night. Can’t get much work done today as I just want to enjoy these little speakers.​

Sierra Luna listening session notes: 10/27​
Started at 10pm, expected to finish by midnight but I found myself having so much fun with these little guys that I ended up listening to them for 6 hours straight.​
Fun – what an absolute fun pair of speakers. Run full range, no sub – very surprising bass and dynamics. Throws a HUGE soundstage with pinpoint imaging – easily equal to the imaging of Sierra-2. Vocals are just a touch more forward, which is good because these cabinets are so tiny.​
Very real feeling of awe, this much dynamic room filling sound from something so small. Completely fills the demo room with extreme ease. LOUD – hit 99dB with boom boom pow at 11 feet distance with no audible compression to my ears, suspect can push 3dB-6dB louder but don’t want to risk damage to this set.​
Direct A/B with HTM-200, Luna bests the 200 in every category. Deeper and even more defined bass which I was aiming for but didn’t actually expect to get there, considering the 200’s sealed enclosure and significantly larger cabinet volume. 200’s sound small with more of a flat wall of sound, Luna’s sound large and a completely enveloping sound. Easier to listen to than the 200's yet with so much more detail - recording venue ambiance comes though easily with Luna, inaudible with 200's. Male vocals are guttural and engaging, 200's sound a bit flat in this regard. Not really fair comparison due to cost differences, but the 200's easily bested every other similar sized speaker I tried and I just don't have anything to compare to, Luna's simply demolish the 200's.​
So much fun listening to these—​
Direct A/B with Sierra-2 crossed at 80Hz with F12 sub, with eyes shut, having a difficult time determining which speaker is playing. Luna’s about 2 – 2.5dB less efficient (likely meet 84dB sensitivity spec) Sierra-2 perhaps just a tad bit smoother vocals at very loud levels, Luna’s are slightly more forward. Timbre matching is dead on. Luna woofer is very impressive.. Sheffield Labs drum track demo sounds fantastic –clean, fast and completely transparent – speakers disappear. Audioslave sounds great -- everything is easy to listen to.​
Perfect balance between efficiency, bass response, transient accuracy is achieved. I feel to make any possible improvement to one specific performance area would result in too much compromise to another aspect. Have never heard anything with this level of performance in such a small cabinet."​

The tuning and design of the port are "intentional":

"The Luna's woofer and cabinet is specifically designed for the exact port tune we are using (~60Hz) Changing the port tune (higher or lower) is not recommended and would only compromise performance."​

It is sad, it seems the more of these companies we see, the more that it is apparent, they are really very sophisticated as selling their story and hooking the customer, but not so good on the execution.
 

BYRTT

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That's a square wave right there;)

View attachment 90591

Good spotted and humor there thanks :) some would argue to relax about it in its narrow high Q signature and therefor non audioable but would imagine if any DAC pre or power amp had that signature in the middle of audioband there would be noice.

Yikes. Another data point for, "If you are planning to spend a decent amount of money, just buy Revels."
Looks you right in Revel's outdoor M55XC have close to exactly same directivity index in horizontal plane but with some performance numbers that looks leave Sierra Luna in the dust..

EDIT ups :confused: curves below is normalized to on axis.
Horinzontals_verse_M55XC.png
 
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MZKM

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Dennis Murphy has mentioned that the 64-10 does not work well in a 2 way design. Because of it's small size, it has to be crossed over very high and results in directivity mismatches and has issues with woofer matching as the woofer gets close to it is breakup. Here are some comments on the AVS thread about going to the Aurum Cantus in the new Mini Monitor:

"Please note that the tweeter in this mini isn't the same as the one in the actual production version. This one has the usual suspect RAAL, and the real one will have an Aurum Cantus AMT driver that can be crossed lower."​
In response to the question: "Hey Dennis how does that Aurum Cantus AMT driver compare to Raal?"

"One doesn't dominate over the other. For a 3-way intended for far field listening, I would go with the RAAL because of its superior horizontal dispersion. But for a 2-way, particularly one that will often be used nearfield, I prefer the AC because it can be crossed lower with less distortion. The AC version of the mini has a little more clarity in the lower treble, and that's more important in this application than a very wide and deep soundstage from, say, a 10 - 12ft listening distance. They're identically priced, so that wasn't a factor."​
"I don't have the Zaph mini's here, so I'm just relying on distant memory. First off, the SB Ceramic woofer dominates the Zaph. It goes way lower, is actually smoother than the Zaph. They both have fairly severe breakup modes up high, but that's not a problem with 4th order crossovers. (I only use 2nd order on the BMR, and then just for the woofer-mid cross) The Zaph was crossed a hair under 3500 Hz, which means the Zaph woofer will be into beaming mode at that point. The SB-AC Mini is crossed at 2,400 Hz, which provides more even radiation over the crossover region and a more clean and focused upper midrange and lower treble. The AC AMT doesn't provide as much air as the RAAL at the very top, but the AC is still quite good in that department and has the same sonic signature--less sssssssssssssssss than a typical dome and more natural on cymbals and triangles. As much as I like the RAAL 64-10X, there's no way to avoid a slightly cloudy lower treble in a 2-way design. And believe me, I've heard them all."​

I think I need to see how long Amir's cue is and send him one of my Mini Monitors. Dennis measurements look pretty impressive:

http://www.philharmonicaudio.com/Measurements.html
Yeah, his updated offerings are pretty good. Like the 2EX though, the only downside I see is a small directivity misnatch, where the tweeter is still radiating widely where the mid/woofer becomes a bit directional. No real helping it though for the BMR, it covers like 500Hz-3000Hz, and there really isn’t anything better.
 

aarons915

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Dennis Murphy has mentioned that the 64-10 does not work well in a 2 way design. Because of it's small size, it has to be crossed over very high and results in directivity mismatches and has issues with woofer matching as the woofer gets close to it is breakup. Here are some comments on the AVS thread about going to the Aurum Cantus in the new Mini Monitor:

Yeah Dennis is pretty honest about the Pros and cons of the Raal while the quotes you posted from Dave at Ascend is much more marketing speak which obviously doesn't match the measurements we see here. I didn't know Dennis is developing a new mini monitor, the Mini Phil with the Raal was the 1st speaker I bought to hear the Raal and I agree there was something missing in the 2-3k range before the tweeter takes over. I built the Zaph ZA 5.2 at the same time to compare the Raal with a dome and preferred the Zaph because of that issue but they were also a bit bright, the Mini Phil could be listened to forever without fatigue. More than just the different frequency response, I was really trying to compare the tweeter range to see exactly what I'm gaining by going to a Raal ribbon over a $20 dome tweeter and for me it's not worth it. Compared to the typical dome they do have slightly stronger early reflection response by about 1 decibel and I really doubt that is going to be audible to the average person, a neutral and smooth response is much more important in my experience.
 

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Thanks Amir!

The directivity seems mostly controlled which is good. What's most peculiar and unfortunate about this is how dramatically different the lower half of the response is from the one on ascend's website.

View attachment 90599

Note how there are blips at 400, 800, and 1.2kHZ, but they are much smaller in amplitude.

I doubt ascend is actively trying to decieve anyone. My guess is a combination of smoothing and the low resolution in the lower midrange of quasi-anechoic measurements yielded a much prettier looking graph. And as Amir noted, I often find these lower midrange issues are less audible than they originally appear.

But goes to show the important of having measurements from different sources. Extensive measurements in isolation aren't quite enough.

I ran into issues with the typical gated measurements I use for crossover development not picking up the severe port resonances in the Helium design also reviewed here. I suspect this "quasi-anechoic" graph was done similarly, with low frequency response spliced in. I was able to pick up the resonances with an ungated close-miked measurement of the port.
 

ROOSKIE

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I want to feel bad for Ascend but I just don't. I feel for the customers who have spend some decent change.
I do respect the difficulty in designing quality products and the little guys have the disadvantage with resources, that said Ascend is big enough and their products cost enough. (these are not budget priced speakers, even if the so called mark-up is less than some competitors that use similar drivers)
These guys can afford to send their products for Kipple testing or Ancheotic chamber measurements and other more microscopic testing.
They may need to charge more if they invest this way however then their products will actually be worth the $2k bill or whatever vs costing $1500 but being worth $500 in comparison to competitors.
 

ctrl

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If the unwanted port resonances in the mid-range deliver 5dB more sound pressure than the intended BR fundamental resonance, one should think about whether there is not a faulty design (this was surely noticed already with the first prototype).

1604254325422.png


To be honest, I can't understand how one can go into production with this.
Such a thing is very damaging to the reputation of small (national) manufacturers. At some point, people will only buy from the big brands, because there they will be bullshited for less money.
There are of course really good loudspeakers from big brands and small manufacturers, had to let off some steam, because this mistake could easily have been avoided (without a big development/research department).

This statement from the company website is a bit exaggerated, at least for this speaker model - or it is meant ironically:
We dare say it, but you simply can not find this type of quality control, care and pride from products that are fully assembled and tested in overseas manufacturing facilities.
 

andreasmaaan

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If the unwanted port resonances in the mid-range deliver 5dB more sound pressure than the intended BR fundamental resonance, one should think about whether there is not a faulty design (this was surely noticed already with the first prototype).

The enclosure and port are a mess here. And the pipe resonances are going to be even higher in output than +5dB compared with the fundamental resonance, since Amir took this measurement in the nearfield.
 
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