• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

KEF Reference 1 META Bookshelf Speaker Review by Erin's Audio Corner

bo_knows

Addicted to Fun and Learning
Joined
Aug 17, 2020
Messages
658
Likes
616
Location
Dallas, Texas USA
Given the wide dispersion on these I don't see why this observation should come as a surprise to you or be that unlikely. I'm demoing the LS50 meta's right now and they also are fairly happy pointed parallel to each other, just as my Snell's are. My understanding is that there is both an imaging advantage for some speakers and a simple "usefulness" advantage. The latter is easy to appreciate - wider sweet spot, more happy listeners. The former I'm not so sure about. Some speakers really only image well when pointed almost or directly at the listener. Just experienced this with a pair of Fyne 502SP's, where the imaging just completely collapsed at anything wider than more or less straight at me. Actually my chief concern for them atm because I'm not sure how narrow the sweet spot will be when listening to these in other rooms. The LS50's are tentatively imaging fairly well set up parallel but more testing is warranted and I'm not final on that and I'm feeling like my favorite thing about the LS50's will be their dynamicism and crystal-clear highs rather than their imaging. From years of experience I can say that my Snell E/III's (with their wide box shape and effectively flat baffle design) are at their best parallel to each other and image fairly well for such a non-ideal shape. I haven't watched the video and have no idea how competent this reviewer is but I would hope they reached their recommendation by playing with different amounts of toe-in and found this to be best, which is not a hard thing to do. If you don't trust them that's totally reasonable- what more do we have to go on than the sum of their reviews...

Not really sure about that second suggestion. Speakers with really wide dispersion patterns seem to make for challenges in narrow rooms so maybe this guy is observing wall reflections and not correctly identifying why they are experiencing them. I'm testing the LS50's in a great room for this because the speakers are on the long wall of a room that's 17x24 and they are quite happy in that space.
Measurements used from Erin's Audio Corner for KEF reference 1 meta.

I will make an assumption that KEF Ref 3 meta has a similar horizontal frequency response.

The response will slope even worse the further you are sitting from the speakers and if the room is highly absorptive.

As you can see the more you are sitting away from the on-axis response (speakers pointing straight ahead towards your ears), the more upper midrange and high frequency drop off. Meaning, that if you have speakers pointed straight ahead, FR will be slopped down and you will hear fewer upper frequencies.
This will make the speaker sound mellow, dull, and more relaxed (pick your word to describe the lack of upper frequencies).
Now, couple this with the aging ears (mind included and nothing personal), and you will not get the best FR, stereo image, or focus in the middle (phantom center speaker).
What you will get (and no argument from me) will be a bigger and less focused "sound stage" and a more relaxed presentation.
This will be a personal choice but if one is striving for a more accurate FR response, stereo image focus and etc, then speakers' tweeters should be crossed slightly behind one's ears ( 1-2 feet behind the MLP).

As for speakers not working in a small room, well I and I'm sure other KEF Ref 3 owners will disagree as well.
Is all about the room dimensions and acoustical treatments. Also, speaker bass reflex ports allow for some bass tuning.
No, I wouldn't recommend this or any larger floor-standing speaker in a small room without any room treatments.
Maybe that's what Steve had in mind.

Below are Erin's subjective listening comments:

  • On-axis is surprisingly nice (expected a bit of a rise as other Kef speakers have shown in the EIR). I initially had them turned off-axis expecting the sound to be too treble-heavy on-axis. Instead what I found was that the HF was too subdued. Putting the speakers practically directly on-axis was much better to me and balanced out the tonality as well as the soundstage.


1656292253490.png
 
Last edited:

cavedriver

Active Member
Joined
Jul 10, 2020
Messages
188
Likes
173
Measurements used from Erin's Audio Corner for KEF reference 1 meta.

I will make an assumption that KEF Ref 3 meta has a similar horizontal frequency response.

The response will slope even worse the further you are sitting from the speakers and if the room is highly absorptive.

As you can see the more you are sitting away from the on-axis response (speakers pointing straight ahead towards your ears), the more upper midrange and high frequency drop off. Meaning, that if you have speakers pointed straight ahead, FR will be slopped down and you will hear fewer upper frequencies.
This will make the speaker sound mellow, dull, and more relaxed (pick your word to describe the lack of upper frequencies).
Now, couple this with the aging ears (mind included and nothing personal), and you will not get the best FR, stereo image, or focus in the middle (phantom center speaker).
What you will get (and no argument from me) will be a bigger and less focused "sound stage" and a more relaxed presentation.
This will be a personal choice but if one is striving for a more accurate FR response, stereo image focus and etc, then speakers' tweeters should be crossed slightly behind one's ears ( 1-2 feet behind the MLP).
I don't think I disagree but if you look at the graph you linked, the 10 and 20 degree data for the KEF's is almost the same as on-axis, this is the advantage of their wide dispersion. I just re-measured my listening setup and my speakers are about 7.5 feet apart and the listener is 11 feet away for an off-axis angle of 18 degrees. This would suggest that toe-ing them in would be unnecessary. Granted I can't say right now what the problem would be with toe-ing them in right now that would encourage not doing it. People say that it puts people outside the stereo image but I've never bothered to confirm it for myself. It is interesting though when I consider measurements of B&W's where people frequently cite them for having too much high frequency output. Perhaps they also have poor off-axis response and the designers expect their listeners to not toe them in that much. Regardless this is previously hashed out terrain, pretty sure there are more informed people that could pick this apart but I can add that this reviewer isn't the only person suggesting that speaker X does not need to be, or should not be toed in.
 

bo_knows

Addicted to Fun and Learning
Joined
Aug 17, 2020
Messages
658
Likes
616
Location
Dallas, Texas USA
I don't think I disagree but if you look at the graph you linked, the 10 and 20 degree data for the KEF's is almost the same as on-axis, this is the advantage of their wide dispersion. I just re-measured my listening setup and my speakers are about 7.5 feet apart and the listener is 11 feet away for an off-axis angle of 18 degrees. This would suggest that toe-ing them in would be unnecessary. Granted I can't say right now what the problem would be with toe-ing them in right now that would encourage not doing it. People say that it puts people outside the stereo image but I've never bothered to confirm it for myself. It is interesting though when I consider measurements of B&W's where people frequently cite them for having too much high frequency output. Perhaps they also have poor off-axis response and the designers expect their listeners to not toe them in that much. Regardless this is previously hashed out terrain, pretty sure there are more informed people that could pick this apart but I can add that this reviewer isn't the only person suggesting that speaker X does not need to be, or should not be toed in.
I'm not a mathematician but I would think the angle will be larger than 10 to 20 degrees if the speaker is pointing straight out in the room.

Anyway, as I mentioned, I enjoyed Steve's subjective review.

I will do what I think it's best for me in my room by using objective data and measurements. ;)

KEF has a decent horizontal dispersion but is not as wide as some other speakers.



1656299087704.png
 

aarons915

Addicted to Fun and Learning
Forum Donor
Joined
Oct 20, 2019
Messages
632
Likes
1,062
Location
Chicago, IL
I'm not a mathematician but I would think the angle will be larger than 10 to 20 degrees if the speaker is pointing straight out in the room.

Anyway, as I mentioned, I enjoyed Steve's subjective review.

I will do what I think it's best for me in my room by using objective data and measurements. ;)

KEF has a decent horizontal dispersion but is not as wide as some other speakers.



View attachment 214951
10 to 20 degrees is perfect to point them straight ahead and still have a strong on-axis response. If they were as strong out to 60-90 degrees then they would sound way too bright in room due to having a flattish in-room response.
 

bo_knows

Addicted to Fun and Learning
Joined
Aug 17, 2020
Messages
658
Likes
616
Location
Dallas, Texas USA
10 to 20 degrees is perfect to point them straight ahead and still have a strong on-axis response. If they were as strong out to 60-90 degrees then they would sound way too bright in room due to having a flattish in-room response.
Blue line is what works for me.

Peace, out.
1656301841544.png
 

jonfitch

Senior Member
Joined
Sep 2, 2019
Messages
387
Likes
434
I should start by saying that I enjoyed Steve's review but a few things got me questioning some of his recommendations.

1) Speakers to be positioned with no toe-in meaning firing straight ahead.

Why? How did he get to this conclusion? Did this recommendation come from KEF?

2) Speakers need to be placed in the large room and recommend smaller Ref 1 for small to medium-size rooms.
Again why?

No scientific proof was provided, only his long-time audiophile experience.

I will need a better explanation before I take his recommendations as gospel.

Needless to say, I disagree with both of those...

Toe-in was a strategy designed to deal with speakers that have non-uniform dispersion to get as much of the on-axis response as possible. This wasn't a problem until the wide baffle 3-way designs fell out of favor in the late 70s for smaller and more decor friendly designs in the 80s onwards with narrower baffles and simplified 2.5 way designs with less crossover complexity. A well designed speaker really shouldn't need any toe in at all.
 
Top Bottom