More details for KEF Audio

[Fasttoys]

This sounds about right for a new system that hasn't been broken-in yet. Give it about 25+ hours of listening, and the sound should warm up with a little more volume and sound richer. High-end speakers need this, and they may very well have a volume limiter on it until listening hours have reached a certain number.

I'm definitely going to have my system on while I drive around for the 1,000 mile break-in period. It will be interesting to see what happens.

Nice write-up!

I typically do this with all my systems, let's be honest the Demo cars where all broken in based off many users and I bet some abuse. (I listened to 3 different Pre-production cars). Someone mentioned Lotus upgraded the amp or something I can't remember who mentioned it, maybe on another forum I am not sure if that is true or false. This production car felt different when it came to sound & speakers. It was not broken in at all as not many people been in the car even the dealer. Like I mentioned it was not super spectacular but good enough to pass a minimum of 50+ % of the new owners. I can't wait till others get their cars to get other feedback.

 

[Nova]

What was strange was the volume control needed to be at 85% to get enough volume out of the speakers.

We have heard from others that the max volume out of the system is low. This is likely because there is a weak link in the system (cough…sub…cough…) that needed to stay below a certain level to not distort or reach its mechanical limit. They could have applied a compressor to the subwoofer amp channel but may also have just chosen to lower the absolute max signal level - it's easier to do and requires no tuning.

In any case, thanks for taking the time to listen to the system and also to give such a detailed write up. I know this is a controversial topic but I personally don't put any worth into break-in. For engineering and prototyping, we do make sure the components are at room temperature, and run a few 10-30 second pink noise bursts through it all just to 1) check everything is connected and level-set correctly, and 2) warm up the voice coils.

There may be some specific drivers that change significantly in their suspension compliance after a period of operation, but the typical modern driver pretty much becomes nominal after 30 seconds of moderate power input.

 

[Eagle7]

I typically do this with all my systems, let's be honest the Demo cars where all broken in based off many users and I bet some abuse. (I listened to 3 different Pre-production cars). Someone mentioned Lotus upgraded the amp or something I can't remember who mentioned it, maybe on another forum I am not sure if that is true or false. This production car felt different when it came to sound & speakers. It was not broken in at all as not many people been in the car even the dealer. Like I mentioned it was not super spectacular but good enough to pass a minimum of 50+ % of the new owners. I can't wait till others get their cars to get other feedback.

I believe there was an increase in the amp power for the production cars compared to the demos. If I remember correctly, wasn't it something like the original amps put out 370 watts and they increased it to 540 watts or something along those lines?

 

[Eagle7]

We have heard from others that the max volume out of the system is low. This is likely because there is a weak link in the system (cough…sub…cough…) that needed to stay below a certain level to not distort or reach its mechanical limit. They could have applied a compressor to the subwoofer amp channel but may also have just chosen to lower the absolute max signal level - it's easier to do and requires no tuning.

In any case, thanks for taking the time to listen to the system and also to give such a detailed write up. I know this is a controversial topic but I personally don't put any worth into break-in. For engineering and prototyping, we do make sure the components are at room temperature, and run a few 10-30 second pink noise bursts through it all just to 1) check everything is connected and level-set correctly, and 2) warm up the voice coils.

There may be some specific drivers that change significantly in their suspension compliance after a period of operation, but the typical modern driver pretty much becomes nominal after 30 seconds of moderate power input.

My belief in break-in is the result of experience. It doesn't seem to matter that much for low to mid level speaker systems, but high-end do seem to have a break-in point. What I've noticed is that out of the box, they sound good but a bit stiff and wooden. Once they reach the break-in point, whatever that might be for that particular speaker, there's a noticeable increase in warmth and richness of the bass and mid tones. The highs don't seem to change (or at least I can't tell if they have), but I can sure hear the difference in the lows and mids. I have to lower the volume too because there's more volume. This happens listening to the exact same music files I was listening to right from the start. I don't change a thing on my settings.

I don't know if it's the coils, or the speaker cone materials, or the combination that seems to loosen up, but it's almost like stretching tight muscles to get them to loosen up so they can perform at their peak ability. Once they do, you can certainly tell the difference.

 

[Nova]

My belief in break-in is the result of experience. It doesn't seem to matter that much for low to mid level speaker systems, but high-end do seem to have a break-in point. What I've noticed is that out of the box, they sound good but a bit stiff and wooden. Once they reach the break-in point, whatever that might be for that particular speaker, there's a noticeable increase in warmth and richness of the bass and mid tones. The highs don't seem to change (or at least I can't tell if they have), but I can sure hear the difference in the lows and mids. I have to lower the volume too because there's more volume. This happens listening to the exact same music files I was listening to right from the start. I don't change a thing on my settings.

I don't know if it's the coils, or the speaker cone materials, or the combination that seems to loosen up, but it's almost like stretching tight muscles to get them to loosen up so they can perform at their peak ability. Once they do, you can certainly tell the difference.

I don't doubt your experience, but our brains are very good at adapting. Sighted bias in sound perception is well established. It's not just speakers but our environment as well. I forgot the exact details of the research but test subjects wore headphones and were placed in different rooms and the music was uniformly rated as worse sounding if the sound signature of the music did not match the expected room acoustics, showing that our mind actually hears a different sound if it believes that the sound should be different, even if the sound is actually exactly the same.

One way to look at this is to convince our mind that there is no expected difference, another is to go with the flow. Neither is right or wrong because our minds actually perceives what it expects to perceive. Both groups of people can be happy even if they derive subjectively different results from the same objective truth.

 

[Eagle7]

I don't doubt your experience, but our brains are very good at adapting. Sighted bias in sound perception is well established. It's not just speakers but our environment as well. I forgot the exact details of the research but test subjects wore headphones and were placed in different rooms and the music was uniformly rated as worse sounding if the sound signature of the music did not match the expected room acoustics, showing that our mind actually hears a different sound if it believes that the sound should be different, even if the sound is actually exactly the same.

One way to look at this is to convince our mind that there is no expected difference, another is to go with the flow. Neither is right or wrong because our minds actually perceives what it expects to perceive. Both groups of people can be happy even if they derive subjectively different results from the same objective truth.

Yes but there's a difference between expected and suddenly noticing a change when you weren't expecting it. I've especially noticed it on headphones. I'm usually listening while working on the computer, and suddenly the sound changes. I don't have it up very loud to begin with, and it's instrumental music so I'm not even particularly paying attention to the music. It's just in the background while I'm working. The sudden change is what gets my attention, and now I'm noticing the music. It's the same stuff I listen to all the time (I have my favorites), so I can tell there's a change. It wasn't something I was expecting or looking for. That's what I've experienced when a speaker reaches its break-in point.

Although I have no experience with KEF speakers, KEF themselves say their speakers benefit from this phenomenon, so it's something I'll be watching out for once I have my car. For everyone who is about to get their new cars in the U.S., just be aware that if the sound system doesn't sound all that great initially, especially in the lows and mids, give it at least 25+ hours of listening and see if it improves.

 

[Nova]

Yes but there's a difference between expected and suddenly noticing a change when you weren't expecting it. I've especially noticed it on headphones. I'm usually listening while working on the computer, and suddenly the sound changes. I don't have it up very loud to begin with, and it's instrumental music so I'm not even particularly paying attention to the music. It's just in the background while I'm working. The sudden change is what gets my attention, and now I'm noticing the music. It's the same stuff I listen to all the time (I have my favorites), so I can tell there's a change. It wasn't something I was expecting or looking for. That's what I've experienced when a speaker reaches its break-in point.

Although I have no experience with KEF speakers, KEF themselves say their speakers benefit from this phenomenon, so it's something I'll be watching out for once I have my car. For everyone who is about to get their new cars in the U.S., just be aware that if the sound system doesn't sound all that great initially, especially in the lows and mids, give it at least 25+ hours of listening and see if it improves.

I think we are getting close to the controversial part of the discussion. I don't have anything else to contribute other than what I have already said on the subject. Again, I don't challenge or question the validity of your experience at all.

 

[lynchy73]

I’ve recently noticed something with this distorted bass when windows are opened thing. If stationary or very low speed, the bass is fine when windows are opened. The issue only occurs at speed with a window even slightly open. Close the windows at speed, distortion dissapears.

Anyone have any ideas what could be going on?

 

[ADC]

I’ve recently noticed something with this distorted bass when windows are opened thing. If stationary or very low speed, the bass is fine when windows are opened. The issue only occurs at speed with a window even slightly open. Close the windows at speed, distortion dissapears.

Anyone have any ideas what could be going on?

My probably offensively oversimplified take is this: The cabin is effectively the inside of a speaker enclosure (for the free-air sub). Opening a window effectively changes it from a sealed enclosure to a ported enclosure, and unloads the woofer (it has no fixed amount of air to push against any more). Driving along with the window open is forcing more air into the cabin, while the woofer is pushing air in and out of the window (port) while doing it's thing... this means the volume of air that the woofer is actually pressing against at any given time is varying wildly, playing havoc with the response.

I'm sure somebody will be along shortly to correct me

 

[Nova]

I’ve recently noticed something with this distorted bass when windows are opened thing. If stationary or very low speed, the bass is fine when windows are opened. The issue only occurs at speed with a window even slightly open. Close the windows at speed, distortion dissapears.

Anyone have any ideas what could be going on?

Yes, cracking the windows while the car is in motion likely either increase or decrease the pressure inside the cabin depending on the aerodynamics of the airstream washing over the window. This pressure differential will cause a constant displacement of the subwoofer cone. This displacement causes asymmetrical behavior in the driver suspension compliance and voice coil magnetic flux density when the subwoofer tries to play a sound - both results in significant non-linear distortion.

 

[lynchy73]

Yes, cracking the windows while the car is in motion likely either increase or decrease the pressure inside the cabin depending on the aerodynamics of the airstream washing over the window. This pressure differential will cause a constant displacement of the subwoofer cone. This displacement causes asymmetrical behavior in the driver suspension compliance and voice coil magnetic flux density when the subwoofer tries to play a sound - both results in significant non-linear distortion.

I don’t think that is what is happening (driver constantly displaced), but it’s certainly possible.

The Emira doesn’t suffer buffeting when you open a window, like most cars do. Maybe the free air subwoofer is absorbing that low frequency sound but in doing so it distorts the bass.

Another possibility is that there might be some sort of feedback/sensing going on and that causes issues under certain circumstances.

Frankly, this isn’t a big issue for me, I just like to understand why it’s happening. The intake on the I4 sounds great, so i do like to crack a window to get a bit more of it.

 

[kitkat]

Haven't even watched it yet but:

Edit: Looks like the "sound off" is the same comparison, but goes a bit more in depth with their selection. Mostly marketing but some interesting stuff like bonding the KEF grill to the door panel.

 

[ADC]

Haven't even watched it yet but:

"like I always say, you can always make a car go quicker..."

(*ahem*... presumably by reducing weight rather than adding it, you mean? :trollface: )

I will say that I do like the sympathy to keeping it feel "OEM plus" (shout out to @FlyNavy01 , as I have that same approach to modifications)

 

[Nova]

Is he seriously implying that Lotus added a tweeter mesh to the A-pilar location to mislead customers. He called it sneaky.

So much talking, so little information. Most of what he implies as bad designs of the OEM system simply isn't true. The OEM system may sound terrible, but not not for the reasons he listed.

"separating the tweeter sound from the midrange sound is going to make a huge difference." <--- a gobsmackingly ignorant statement to make for anyone who professes to be an audio professional.

The way they did the before/after sound comparison is also incredibly dishonest.

What they did in terms of the install and eliminating squeaks and rattles is top notch work.

 

[Nova]

"like I always say, you can always make a car go quicker..."

(*ahem*... presumably by reducing weight rather than adding it, you mean? :trollface: )

I will say that I do like the sympathy to keeping it feel "OEM plus" (shout out to @FlyNavy01 , as I have that same approach to modifications)

I'm not sure how "OEM Plus" this is since they physically cut off the original front speaker pods with a grinder wheel. Maybe he forgot about that when shooting this video.

 

[ADC]

I'm not sure how "OEM Plus" this is since they physically cut off the original front speaker pods with a grinder wheel. Maybe he forgot about that when shooting this video.

oh... really?! Clearly I wasn't paying attention, as I just listened to him waffling about using the factory fixing/clip points for the speaker spacer ring, and assumed that meant they unclipped the originals...

In my defence, it is Friday evening, and I had a glass of wine in hand

 

[PsymonR]

Is he seriously implying that Lotus added a tweeter mesh to the A-pilar location to mislead customers. He called it sneaky.

So much talking, so little information. Most of what he implies as bad designs of the OEM system simply isn't true. The OEM system may sound terrible, but not not for the reasons he listed.

Yep, that's what he was implying, there couldn't possibly be any other reason surely... oh wait the base non-KEF system isn't going to have the Uni-Q speakers and they've probably just designed the one A-pillar trim to use for FE and (eventually) base.

Talking of sneaky, they're posting the video as a review when it is really just there to push their own system, that's kinda sneaky if you ask me as it's not exactly going to be impartial

 

[Fasttoys]

Like I mentioned in my pervious post, I think these guys do great work & I like the attention to detail and engineering behind it. I get you may not like the presenter but the execution IMO ( I have Installed over 50 high end systems) is top. I worked on my Lotus Evora for 2 1/2 weeks and it was the hardest system I have ever installed. I am interested to hear what others will say when their car arrives.

 

[EMIRADILEMMA]

Quick question, for the audiophiles and people with experience modifying car sound systems. Could an easy fix be just installing extra tweeters in the a-pillars? It wouldn't revolutionise the sound system it would improve it surely? (an option I am considering)

 

[Porter]

Quick question, for the audiophiles and people with experience modifying car sound systems. Could an easy fix be just installing extra tweeters in the a-pillars? It wouldn't revolutionise the sound system it would improve it surely? (an option I am considering)

No. There's nothing wrong with the tweeters that are already there. KEF makes a very good driver.