KEF Blade 2 vs Ascend ELX Towers as End Game

[PristineSound]

If you ever have the time (and energy), definitely compare your ELX Towers to your S7t in the same room, easier to move the ELX to the basement compared to the 120+ pound Perlisten beasts. Room acoustics is critical when it comes to imaging, soundstage and even what details you can hear.

Will absolutely give it a try.

But I want to emphasize that the ELX RAAL is absolutely a beast of a speaker and better than any other speakers that I previously own, including a pair of Revel F226Be. You simply cannot go wrong with the ELX RAAL even when compared to much more expensive speakers.

 

[a4eaudio]

My first 'expensive" speaker. I loved them ... my wife not so much
She promised i would be buried if them if i kept them

I'm so sorry to hear this, when is the funeral?

 

[Chrispy]

Was hoping more for a why does it matter or no opinion type choice in the poll.....few will have heard both in their own room I would think in any case but glad there was a vote for both choice so I did that instead. Be happy to experience either/both of those speakers if someone else pays....

 

[Absolute]

I absolutely believe that the ELX could beat the Blade in a random comparison. Why do I think that? Because both speakers are very good tonality wise, but differ a lot in how it disperses the sound into a room. Let's take a look.

First is the direct sound, which is crucial for sound quality. Here, the difference is far from great. Listening window is largely within 1 dB of each other;

They are both very good here. The Blade has more power in the bass, which can be a good thing or a bad thing, depending on the room and placement, but otherwise they are very similar - if we take the scale into account. Nitpicking about the ups and downs of a minute difference can be interesting for some, but for me it's far more interesting how they compare in terms of reflections. Or rather, the specifics of the reflections.
I don't believe Total reflection power is all that relevant because I don't think it's possible to accurately weight the importance of each reflection across different rooms.

Why do I believe that? Mostly because of my own experiments with acoustic treatment and different speakers across different rooms with different results. But also because of circumstantial evidence throughout the thousands of discussions regarding preferred dispersion. Some like narrow, some like wide and some think they have found a preferred approximate. I myself have found the vertical reflections to be more important than I first thought. I have also found that I like wide horizontal dispersion.
We know what the research says, but most of the blind tests done by research seems to be done in a large room with considerable distance to most of the reflective surfaces. As far as I'm aware, no research has dived into what happens to preference if you take a "perfect" speaker with wide horizontal and narrow vertical vs a narrow horizontal and wide vertical "perfect" speaker and place it in a small, reflective room and then compare the results to a large room. Similarly, as far as I'm aware no research has dived into what happens if you try to tailor different frequency spectrum's to different dispersion goals while keeping the direct sound perfect.
Is it even possible to get close to an optimal dispersion pattern for reflective small rooms?

I don't know the answer to that, but I do believe the answer for why a certain speaker may beat another speaker in some rooms but not others lie in the smallest of details concerning dispersion. And here's the interesting part about ELX vs Blade 2. The ELX has about 4 dB less reflective sound power vertically - which is about the same effect of dispersion control as you would expect from a cardioide speaker. (Kii Three 4.6 dB)

Then there's the other benefit of RAAL tweeters, the wide horizontal dispersion. We've all heard people say they have this mysterious ethereal air and effortlessness about them. What's that all about? If I were to guess, I'd say the answer lies in the very wide dispersion and in the relative relationship between vertical and horizontal reflections.
The ELX side reflection power is about 3 dB higher from 2kHz and up.

If we take the estimated in-room response at face value, the speakers are within 1 dB of each other. But diving into the details we see that they differ greatly in how they achieve that in-room response. Is either of them closer to an ideal than the other? Maybe. For all rooms? Unlikely. For all users? Not a chance.

Bass response differences aside, these two speakers are more different in their path to excellency than they are more or less excellent. If matched in the bass department, I would still expect the Blade to be preferred in more rooms due to smoother response overall. But my confidence in any given random comparison in short-term listening would be about 50 %. Longer term listening/comparison I would change it to about 75 % confidence in favor of Blade because I do believe the Blades smoother LW response between 2-7 kHz and the directivity error of ELX (some reflections combine to create a peak) between 2-3 kHz may become noticeable over time.

 

[PristineSound]

I absolutely believe that the ELX could beat the Blade in a random comparison. Why do I think that? Because both speakers are very good tonality wise, but differ a lot in how it disperses the sound into a room. Let's take a look.

First is the direct sound, which is crucial for sound quality. Here, the difference is far from great. Listening window is largely within 1 dB of each other;
View attachment 458106

They are both very good here. The Blade has more power in the bass, which can be a good thing or a bad thing, depending on the room and placement, but otherwise they are very similar - if we take the scale into account. Nitpicking about the ups and downs of a minute difference can be interesting for some, but for me it's far more interesting how they compare in terms of reflections. Or rather, the specifics of the reflections.
I don't believe Total reflection power is all that relevant because I don't think it's possible to accurately weight the importance of each reflection across different rooms.

Why do I believe that? Mostly because of my own experiments with acoustic treatment and different speakers across different rooms with different results. But also because of circumstantial evidence throughout the thousands of discussions regarding preferred dispersion. Some like narrow, some like wide and some think they have found a preferred approximate. I myself have found the vertical reflections to be more important than I first thought. I have also found that I like wide horizontal dispersion.
We know what the research says, but most of the blind tests done by research seems to be done in a large room with considerable distance to most of the reflective surfaces. As far as I'm aware, no research has dived into what happens to preference if you take a "perfect" speaker with wide horizontal and narrow vertical vs a narrow horizontal and wide vertical "perfect" speaker and place it in a small, reflective room and then compare the results to a large room. Similarly, as far as I'm aware no research has dived into what happens if you try to tailor different frequency spectrum's to different dispersion goals while keeping the direct sound perfect.
Is it even possible to get close to an optimal dispersion pattern for reflective small rooms?

I don't know the answer to that, but I do believe the answer for why a certain speaker may beat another speaker in some rooms but not others lie in the smallest of details concerning dispersion. And here's the interesting part about ELX vs Blade 2. The ELX has about 4 dB less reflective sound power vertically - which is about the same effect of dispersion control as you would expect from a cardioide speaker. (Kii Three 4.6 dB)

View attachment 458109


Then there's the other benefit of RAAL tweeters, the wide horizontal dispersion. We've all heard people say they have this mysterious ethereal air and effortlessness about them. What's that all about? If I were to guess, I'd say the answer lies in the very wide dispersion and in the relative relationship between vertical and horizontal reflections.
The ELX side reflection power is about 3 dB higher from 2kHz and up.

View attachment 458110

If we take the estimated in-room response at face value, the speakers are within 1 dB of each other. But diving into the details we see that they differ greatly in how they achieve that in-room response. Is either of them closer to an ideal than the other? Maybe. For all rooms? Unlikely. For all users? Not a chance.

Bass response differences aside, these two speakers are more different in their path to excellency than they are more or less excellent. If matched in the bass department, I would still expect the Blade to be preferred in more rooms due to smoother response overall. But my confidence in any given random comparison in short-term listening would be about 50 %. Longer term listening/comparison I would change it to about 75 % confidence in favor of Blade because I do believe the Blades smoother LW response between 2-7 kHz and the directivity error of ELX (some reflections combine to create a peak) between 2-3 kHz may become noticeable over time.

There is only one way to find out. Dave offered his facility to do a shoot out, all we need is someone who has a Blade and willing to bring it over to do this shoot out.

Too bad I live in the East Coast, otherwise, I would offer to bring my Perlisten S7t over for a shootout since Dave has offered to host with food, drinks and scotch

 

[Audio Science Pal]

I have the ELX RAAL and I also have the Perlisten S7t.

Very nice!

 

[PristineSound]

Very nice!

Very blessed to have sites like ASR, Spinaroma and Erin's Audio Corner, along with scientific literatures like Sound Reproduction, LDC and The Science of Sound to help me wisely spend what is to me a small fortune for a very selfish hobby.

Even more blessed to have companies like Ascend Acoustics and Perlisten making great products.

For all those out there, before you go spend a small fortune with the traditional "high end" usual suspect speaker brands, whose names I will not mention, please do your research based on science and not based on marketing shrewdness or audio fairy tales.

 

[aarons915]

Considering the price and really everything else this is an odd comparison to make. The Blades are simply in another class and they should be given the price difference, they measure quite a bit smoother, especially the directivity which makes them more EQ'able should the need arise. They have much more bass so in my opinion that should be somewhat normalized if you were to compare them unless you don't plan on using subs. Also, the 70-20 is almost 1" wide, it's not that wide in dispersion, people constantly mix it up with the 64-10 but you can see in the early reflection comparison someone posted, the Blades generally have stronger early reflections. Since the Blades are a somewhat odd design they might not be someone's cup of tea but objectively they are superior in pretty much every way.

 

[kemmler3D]

We would love to host this at our facility! We do have the capability for precise level matched A/B comparisons, it would be a lot of fun. We would supply food, drinks and some good scotch

My first and only experience with the Blade's was at CES when they were first introduced, this might have been back in 2008 / 2009. They were in a HUGE room (too large for the speakers) and it wasn't a good demo and I left a bit disappointed (not at the fault of the speakers)

If anyone has a pair, is somewhat local to us, and interested in (carefully) bringing them to our place, please reach out...

Just want to point out that it takes confidence in engineering to offer this, let alone against speakers that are regularly mentioned in "best in the world" discussions. From the manufacturer's point of view, any shootout is risky because the opinions of the listeners can be wrong.

From measurements I've seen the confidence is justified. I'll follow this with interest if it happens!

 

[amper42]

Just want to point out that it takes confidence in engineering to offer this, let alone against speakers that are regularly mentioned in "best in the world" discussions. From the manufacturer's point of view, any shootout is risky because the opinions of the listeners can be wrong.

From measurements I've seen the confidence is justified. I'll follow this with interest if it happens!

It's a safe bet no one will pack up their Blade two Meta and show up at Ascend.

When you listen to speakers in your own home listening space it's pretty easy to notice differences in speakers as you have plenty of time to do so in a defined reference space you are familiar with. Taking my speakers to another space to compare them wouldn't offer much. It's much like listening to multiple speakers at a stereo shop. You don't have unlimited time and don't have a good listening reference for the room.

The average ear height for a seated adult male, measured from the floor to the ear while sitting in a typical chair or sofa generally falls between 36 and 42 inches. One of the design flaws with the ELX is a RAAL tweeter mounted only 34" off the ground. The fact that the tweeter doesn't offer much vertical dispersion makes it worse. When you compare that to the Revel F228Be tweeter mounted with a 43" height or the Revel F328Be with a 47.5" tweeter height you hear a quality difference. Especially, from 7-9 feet back. Even the BMR Tower offers the RAAL mounted 37" high. In my opinion, the lower mounting height of the ELX RAAL tweeter can impede the audio presentation.

 

[ta240]

Was hoping more for a why does it matter or no opinion type choice in the poll.....few will have heard both in their own room I would think in any case but glad there was a vote for both choice so I did that instead. Be happy to experience either/both of those speakers if someone else pays....

It may matter to different people for different reasons.

Some may like the idea of being able to use only numbers to categorize and rate every aspect of audio reproduction and some may like the idea that people who buy high end speakers like Blades are as 'silly' as those that buy more expensive amps. Imagine all the speaker threads turning into "You are a fool, you wouldn't be able to tell the difference between your speakers and...."

There seems to be a temptation to progress towards including speakers in "They all sound the same if they measure the same" like amps. Despite having so many different factors to the sound of a speaker, not only in the sweet spot but when listening throughout the room and their interaction with the room.

I've commented on it recently that more and more reviews of small speakers tend to downplay the caveats of 'for their size' and 'for their price' or even 'at this specific measurement' when saying speakers are 'the best' or 'the new reference'. I've yet to see anyone review these new small stand mount speakers and close with "I'm selling my large, expensive speakers and getting these."; which is what would happen if they truly were the 'best'.

 

[AscendDF]

It's a safe bet no one will pack up their Blade two Meta and show up at Ascend.

When you listen to speakers in your own home listening space it's pretty easy to notice differences in speakers as you have plenty of time to do so in a defined reference space you are familiar with. Taking my speakers to another space to compare them wouldn't offer much. It's much like listening to multiple speakers at a stereo shop. You don't have unlimited time and don't have a good listening reference for the room.

The average ear height for a seated adult male, measured from the floor to the ear while sitting in a typical chair or sofa generally falls between 36 and 42 inches. One of the design flaws with the ELX is a RAAL tweeter mounted only 34" off the ground. The fact that the tweeter doesn't offer much vertical dispersion makes it worse. When you compare that to the Revel F228Be tweeter mounted with a 43" height or the Revel F328Be with a 47.5" tweeter height you hear a quality difference. Especially, from 7-9 feet back. Even the BMR Tower offers the RAAL mounted 37" high. In my opinion, the lower mounting height of the ELX RAAL tweeter can impede the audio presentation.

I think you would be quite surprised as to what speakers’ customers have brought here to demo over the years. It’s a long list and we’ve had speakers here that cost quite a bit more than Blade 2’s.

Our demo room is nothing like a stereo shop. Our room is similar in size and shape to typical listening environments. We have 8 removable 4’ x 4’ x 5” thick acoustic foam damping panels at 1st, 2nd and even 3rd reflection points. We can easily adjust the room to be lively or extremely well damped, or anything in between. In addition, we have never put a time limit on demo’s – we have literally had people here listening all day long. We go out of our way to accommodate.

I should also mention that we have an advanced switching device that allows for true A/B switching (at the pre-amp level or amp out level) as well as precise level matching in 1/10th of a dB increments. Add to that a fantastic ATI 4 channel amp that we purchased specifically for direct A/B comparisons. I would argue just the opposite; you will hear far more differences between speakers in our demo room than in your own room and certainly compared to ANY stereo shop. When was the last time you were in a room that, within a few minutes, can be adjusted to simulate very different listening environments or allowed you to listen for 6-8 straight hours under near ideal circumstances?

Regarding what you claim to be a design flaw regarding tweeter height.

Nearly every one of our tower customers uses either spiked feet or bumpers. This puts the center of the RAAL at a minimum of 35 ½ inches in height or as high as 37”. That aspect is adjustable. The very specific driver orientation of our tower is not by accident nor a design flaw… As someone posted the measurements here, the vertical directivity is extremely well controlled – not just because of the RAAL ribbon, but also throughout the midrange. The benefits of controlled vertical directivity in tower speakers is important because they aren’t like bookshelf speakers where someone can easily adjust the height. Floor and ceiling reflections smear detail and imaging, and as many believe, that higher level of vertical directivity accounts for much of the incredible detail the ribbons produce.

That being said, and as I mentioned previously, the ideal vertical listening window for the RAAL in our towers is +/- 10 degs. So, let’s assume someone is sitting at 7’ back (like you mentioned) and they are extremely tall such that their ear-height while sitting is at 40”. Let’s also assume they are not using the included spiked feet or any rubber bumpers such that the middle of the ribbon is at 34” in height. Doing the math, at 7’ back this puts the listener’s ears at a vertical off-axis angle to the center of the ribbon at a miniscule 4 degs above the center of the ribbon. At 4 degs above or below, there is literally no change, not even a smidgeon of a dB difference. Since this is a site that relies on measurements and science, you can clearly see this in the vertical contour plot of the speaker. In addition, the vast majority of listeners do not sit up straight when listening, they lean back in the couch or chair, almost never sitting upright – upright is where that average ear-height for a seated adult male comes in… But even in the scenario you presented, it has zero effect on what someone will hear. At a listening distance of 7 feet, one’s ears must be a minimum of 16” above or below the center of the ribbon to be outside that +/- 10 degree vertical listening window. That is just not going to happen.

Look, this thread is about comparing our ELX Ribbon Towers (a speaker you have never heard) vs Kef Blade 2’s, a speaker you also likely have never heard. I have never made this direct comparison, and as such, I am very interested in it, but the info you posted needed to be corrected.

I will say that based on the vast amount of direct A/B comparisons I have hosted (including dozens of Kef models, many of which use the exact same Uni-Q driver as the Blade 2), if we accommodate for the differences in bass extension by high passing each speaker at 60Hz or so, and add in a subwoofer – I would be willing to bet a bottle of Glenlivet 18 (my personal favorite) it would be very close to 50%-50%.

So let’s do this! If any Blade 2 owners are interested, please contact me, Ascend will cover any costs involved in getting the speakers here and back. This is strictly for my own curiosity, if we can make this happen, I won’t even publicly share the results and when we do comparisons like this, I generally stay out of the room and give the remotes to the listeners. I would do my own listening when everyone has left.

 

[ta240]

Our demo room is nothing like a stereo shop.

That is a demo room I'd like to visit. Those little Sierra LXs are seriously impressive. I tend to end up sitting on the floor and all over the room so the Titan dome would be the ELX for me.
Maybe its time to plan a San Diego vacation and throw out there "hey, lets drive up the coast a bit"

 

[AscendDF]

That is a demo room I'd like to visit. Those little Sierra LXs are seriously impressive. I tend to end up sitting on the floor and all over the room so the Titan dome would be the ELX for me.
Maybe its time to plan a San Diego vacation and throw out there "hey, lets drive up the coast a bit"

Definitely come visit! All we ask is that you give us a about a week's notice. Plus, San Clemente is a beautiful beach town with lots of great restaurants, bars, live music and breweries.

Glad to know that you are enjoying the LX. Since you like sitting on the floor, I agree - the ELX Titan's would be the better choice.

 

[Absolute]

@AscendDF Your curiosity and enthusiasm to test and learn seems genuine, and your willingness to spend both time and money to accommodate random comparisons that you may not benefit from is commendable. Your listening room set-up with adjustable acoustics sounds like an ideal testing facility for speaker testing purposes.
Which makes me curious about many things, some of which I hope you would be willing to answer;

- Have you had a realization about speaker/room interaction in terms of sound quality that made you go "wait, what?" If so, which was the most surprising?

- Have you found a significant preference in general in terms of acoustics, or is it rather random depending on dispersion and listener preference?

- As an enthusiast, Klippel owner and manufacturer with "unlimited" potential to experiment and test, I can only imagine how many ideas and theories you have explored - or wish to explore. Have you found areas where you feel the Spinorama over-estimate or under-estimate certain things that puts you in somewhat of a conundrum when designing speakers for the more scientifically oriented market? No need to disclose any secrets, just curious.

 

[PristineSound]

Nearly every one of our tower customers uses either spiked feet or bumpers.

I can confirm that for myself:

Ascend Acoustics Owners' Lounge

Hey All - I want to create a thread for Ascend Acoustics owners. The purpose is to discuss all things related to Ascend Acoustics speakers, including but not limited to: Optimal placement Proper amplification Other equipment/brands that works well with Ascend Acoustics Your experience with...

audiosciencereview.com

That being said, and as I mentioned previously, the ideal vertical listening window for the RAAL in our towers is +/- 10 degs. So, let’s assume someone is sitting at 7’ back (like you mentioned) and they are extremely tall such that their ear-height while sitting is at 40”. Let’s also assume they are not using the included spiked feet or any rubber bumpers such that the middle of the ribbon is at 34” in height. Doing the math, at 7’ back this puts the listener’s ears at a vertical off-axis angle to the center of the ribbon at a miniscule 4 degs above the center of the ribbon. At 4 degs above or below, there is literally no change, not even a smidgeon of a dB difference.

Yup, basic geometry. I also want to add that in my experience, I have zero issues with the vertical directivity pattern of the ELX RAAL.

So let’s do this! If any Blade 2 owners are interested, please contact me, Ascend will cover any costs involved in getting the speakers here and back. This is strictly for my own curiosity, if we can make this happen, I won’t even publicly share the results and when we do comparisons like this, I generally stay out of the room and give the remotes to the listeners. I would do my own listening when everyone has left.

Dave, if you ever are in the NY/NJ area, please message me, I would like to invite you over my place to audition the Perlisten S7t vs the ELX RAAL, I also have the Neumann KH-120II DSP. I just want your thoughts on it, perhaps provide some recommendations on setup, but more so, I just want to meet you and learn from you about all things speaker and audio related.

 

[amper42]

Yes, I can easily imagine ELX owners want to optimize treble by using spikes and any other stilt mechanism they can find to raise the RAAL tweeter closer to ear height. The nice thing about BMR Monitors is 28" stands lift the RAAL to a height of 45". That's exactly at ear level in my office. It sounds quite nice at this height. The other nice thing about the BMR monitor is it doesn't suffer from the effects of an MTM configuration. I find the RAAL works best at ear height or even a little higher for optimal results. With the ELX RAAL mounted at 34" height it's almost impossible to get the same tweeter results as the BMR Monitor on 28" stands.

Updating the Sierra Tower design was a great idea and the drivers used seem substantial. But limiting the update to mounting the new drivers in the same old Sierra Tower cabinet won't maximize results. I would have done away with the MTM design, lifted the RAAL to 43" height minimum and used a larger cabinet to support increased bass response.

I understand Ascend wanted to offer a kit for existing Sierra Tower owners to upgrade but that path creates too many compromises for those wanting a world class speaker cabinet to go with world class speakers.

 

[Ricardojoa]

Yes, I can easily imagine ELX owners want to optimize treble by using spikes and any other stilt mechanism they can find to raise the RAAL tweeter closer to ear height. The nice thing about BMR Monitors is 28" stands lift the RAAL to a height of 45". That's exactly at ear level in my office. It sounds quite nice at this height. The other nice thing about the BMR monitor is it doesn't suffer from the effects of an MTM configuration. I find the RAAL works best at ear height or even a little higher for optimal results. With the ELX RAAL mounted at 34" height it's almost impossible to get the same tweeter results as the BMR Monitor on 28" stands.

Updating the Sierra Tower design was a great idea and the drivers used seem substantial. But limiting the update to mounting the new drivers in the same old Sierra Tower cabinet won't maximize results. I would have done away with the MTM design, lifted the RAAL to 43" height minimum and used a larger cabinet to support increased bass response.

I understand Ascend wanted to offer a kit for existing Sierra Tower owners to upgrade but that path creates too many compromises for those wanting a world class speaker cabinet to go with world class speakers.

But the elx is not a mtm design. The mid crosses the lower two woofers at much lower frequencies which on the contour plot shows no issue at all

 

[Mark609]

What are the crossover frequencies on the ELX?

 

[Audio Science Pal]

Very blessed to have sites like ASR, Spinaroma and Erin's Audio Corner, along with scientific literatures like Sound Reproduction, LDC and The Science of Sound to help me wisely spend what is to me a small fortune ...

Quality audio equipment is a bargain compared to so many other things.