More details for KEF Audio

[dgrace]

I think the argument about locating tweeters up on the pillars rather than down in the door card is that they'll have an unobstructed path to the ears. Putting them down in the door card means that they'll end up bouncing off knees and seats before the high frequencies get to you, and high frequencies attenuate much more quickly on contact with soft material. The downside is then you need to worry about phase differences between your midrange drivers in the doors and the pillar tweeters.

 

[VL3X]

Sorry if I missed it, but did Lotus lower the KEF system wattage? I just checked the configurator site and noticed it now says 128w... or is this just another website typo?

 

[Nova]

I think the argument about locating tweeters up on the pillars rather than down in the door card is that they'll have an unobstructed path to the ears. Putting them down in the door card means that they'll end up bouncing off knees and seats before the high frequencies get to you, and high frequencies attenuate much more quickly on contact with soft material. The downside is then you need to worry about phase differences between your midrange drivers in the doors and the pillar tweeters.

Thats another inaccurate point of the video. Looking at POV driving videos, it's pretty clear that the knees are not in the way, though. There is a direct line of sight path between passenger/driver heads and the two speakers.

 

[Nova]

Sorry if I missed it, but did Lotus lower the KEF system wattage? I just checked the configurator site and noticed it now says 128w... or is this just another website typo?

View attachment 36487

That looks to be the base car. They messed up the specs.

 

[Fasttoys]

Thats another inaccurate point of the video. Looking at POV driving videos, it's pretty clear that the knees are not in the way, though. There is a direct line of sight path between passenger/driver heads and the two speakers.

Sorry you never put tweeters at that level, the guys in the video like it or not did a good job with fabricating and installation. On the comments of how it sounds no way to know with out being in the car.

From KEF website:
The tweeter, or HF driver, should be at – or as close as possible to – ear level, so you’ll need to take the vertical plane into account when designing your setup
https://us.kef.com/blogs/news/5-tips-for-positioning-your-speakers

My 2 cents: Speaker Placement Matters​

When we talk about speaker placement for the front stage of our vehicles, the options are typically a stock location in the lower part of the front door, a location in the middle or upper portion of the door, the dash or in a custom pod on the A-pillar. It should come as no surprise that every location has a benefit and an equal number of drawbacks. For mid-bass drivers used in a three-way front stage, the door location often works well. Some will go further with the installation and have custom mounting solutions created in the kick panels. If this driver is going to play up to 400 or 500 Hz, this “farther away” position can help with the perceived depth of the soundstage. The same concept applies to midrange drivers. If they are installed in the doors, as would be found in many Porsches and BMWs, the soundstage can appear to span the car, but comes from a position that’s in line with the steering wheel. Mounting the speakers in pods on the A-pillars can move that soundstage deeper into the dash. Finally, speaker positions in the corners of the dash, right at the base of the windshield, are about as far away from the listening position as is possible and help to create a soundstage that seems to come from the rear edge of the hood. Some listeners don’t concern themselves with the sound source, while others weigh it heavily in their system design considerations.
The angle at which tweeters are aimed matters. Suppose you want to have any chance of hearing the highest of frequencies. In that case, tweeters need to be aimed toward the listening position or pointed up into the windshield so their output can reflect off the glass and “spray” into the vehicle interior. Tweeters mounted in sail panels can help to increase the perceived width of a soundstage is another consideration in where the music seems to come from.

Think it’s best for everyone to evaluate the systems after they get the car. I gave my 2 cents and can’t prove my points till others own the car and agree or disagree with me.

 

[Nova]

Sorry you never put tweeters at that level, the guys in the video like it or not did a good job with fabricating and installation. On the comments of how it sounds no way to know with out being in the car.

Speaker Placement Matters​

When we talk about speaker placement for the front stage of our vehicles, the options are typically a stock location in the lower part of the front door, a location in the middle or upper portion of the door, the dash or in a custom pod on the A-pillar. It should come as no surprise that every location has a benefit and an equal number of drawbacks. For mid-bass drivers used in a three-way front stage, the door location often works well. Some will go further with the installation and have custom mounting solutions created in the kick panels. If this driver is going to play up to 400 or 500 Hz, this “farther away” position can help with the perceived depth of the soundstage. The same concept applies to midrange drivers. If they are installed in the doors, as would be found in many Porsches and BMWs, the soundstage can appear to span the car, but comes from a position that’s in line with the steering wheel. Mounting the speakers in pods on the A-pillars can move that soundstage deeper into the dash. Finally, speaker positions in the corners of the dash, right at the base of the windshield, are about as far away from the listening position as is possible and help to create a soundstage that seems to come from the rear edge of the hood. Some listeners don’t concern themselves with the sound source, while others weigh it heavily in their system design considerations.
The angle at which tweeters are aimed matters. Suppose you want to have any chance of hearing the highest of frequencies. In that case, tweeters need to be aimed toward the listening position or pointed up into the windshield so their output can reflect off the glass and “spray” into the vehicle interior. Tweeters mounted in sail panels can help to increase the perceived width of a soundstage is another consideration in where the music seems to come from.

Think it’s best for everyone to evaluate the systems after they get the car. I gave my 2 cents and can’t prove my points till others own the car and agree or disagree with me.

In a post earlier in this thread, I agreed that the installers did a wonderful job with the install cosmetic/workmanship wise, it's top quality work. Both thumbs up from me.

My posts are focused on what they said about why they thought the OEM system was no good, and why they chose to do some of the things they did. The OEM system could sound terrible - I don't know - but if so, it's not for the reasons they mentioned. Their system could be the best system in the world ever - again I don't know - but if so, it's not for the reasons they mentioned.

I appreciate all that you wrote above, but some of the claims you made are simply not true. Just as one example, you don't get deeper sound stage by moving a midbass speaker playing up to 500Hz further away. Sound stage perceived depth is primarily a function of the level of direct sound vs reflected sound. The higher the amount of reflected sound compared to the direct sound, the deeper the sound stage will appear to be - up to the limit of subjective preference. We know that the listening room reflects sound at both high and low frequencies. At low frequencies below about 800-1kHz, the wave lengths are so long that reflected sound primarily develops cancellation/reinforcement spots in the car, largely dependent on cabin modes. These cancellation/reinforcement spots are indistinguishable to our ears from the direct sound - we don't hear them as reflections, just louder/quieter depending on which spot in the car you are listening at. It's at higher frequencies above 1kHz that the timing differences between reflected vs direct sound in a car, which are usually 3ms for the primary reflection, and 6ms for the secondary, becomes meaningful enough for reflected sound to be detected as a distinct sound from the direct sound by our ears. Therefore, it's simply not possible that moving the midbass driver further away would cause the sound stage to be "deeper" if the midbass primarily plays lower frequencies - 500Hz in your example. You may activate different cabin modes, and it will certainly sound different - I will note that the kick panel location is usually a corner of the cabin - but definitely not a deeper sound stage.

Look, I'm not here to win an argument - I care about sound quality and I'm concerned about the sound quality of the KEF system in the Emira based on how poorly it's been reviewed by owners and third parties. I just want to press the point that our criticism of the system and any corrective actions we take should be based on facts and logic.

 

[Fasttoys]

In a post earlier in this thread, I agreed that the installers did a wonderful job with the install cosmetic/workmanship wise, it's top quality work. Both thumbs up from me.

My posts are focused on what they said about why they thought the OEM system was no good, and why they chose to do some of the things they did. The OEM system could sound terrible - I don't know - but if so, it's not for the reasons they mentioned. Their system could be the best system in the world ever - again I don't know - but if so, it's not for the reasons they mentioned.

I appreciate all that you wrote above, but some of the claims you made are simply not true. Just as one example, you don't get deeper sound stage by moving a midbass speaker playing up to 500Hz further away. Sound stage perceived depth is primarily a function of the level of direct sound vs reflected sound. The higher the amount of reflected sound compared to the direct sound, the deeper the sound stage will appear to be - up to the limit of subjective preference. We know that the listening room reflects sound at both high and low frequencies. At low frequencies below about 800-1kHz, the wave lengths are so long that reflected sound primarily develops cancellation/reinforcement spots in the car, largely dependent on cabin modes. These cancellation/reinforcement spots are indistinguishable to our ears from the direct sound - we don't hear them as reflections, just louder/quieter depending on which spot in the car you are listening at. It's at higher frequencies above 1kHz that the timing differences between reflected vs direct sound in a car, which are usually 3ms for the primary reflection, and 6ms for the secondary, becomes meaningful enough for reflected sound to be detected as a distinct sound from the direct sound by our ears. Therefore, it's simply not possible that moving the midbass driver further away would cause the sound stage to be "deeper" if the midbass primarily plays lower frequencies - 500Hz in your example. You may activate different cabin modes, and it will certainly sound different - I will note that the kick panel location is usually a corner of the cabin - but definitely not a deeper sound stage.

Look, I'm not here to win an argument - I care about sound quality and I'm concerned about the sound quality of the KEF system in the Emira based on how poorly it's been reviewed by owners and third parties. I just want to press the point that our criticism of the system and any corrective actions we take should be based on facts and logic.

Nova, have you heard the system in the Emira? How long did you listen to it? When are you expecting to get your car? Are you getting a FE1 with the Kef system?

Building a system in a car is very difficult., I have done many in my time from BMW, Porsche, Audi, Lotus and many more Higher end cars. When I built mine in my Evora it came out pretty good and it was much better than the original system. We all know that the Emira has very limited space & is very similar to the Evora. I am a little surprised and annoyed that KEF allowed that to be the final product especially after hearing it in the Lotus SUV. SUV system was very nice, I was hoping the Emira even in its limit space would be at least 50% as good and IMO it’s not even close.

 

[Speedy Emira]

I know I’m stating the obvious but if weight is another big issue on top of space for the ideal install why couldn’t they have used something like a high end soundbar. My son has a £1000 soundbar below his 65inch tv that has no base or and doesn’t use the TVs speakers. It sounds great, even when playing PlayStation games or films requiring surround sound and the speakers are tiny. Surely someone could develop this concept for cars?

 

[Eagle7]

I know I’m stating the obvious but if weight is another big issue on top of space for the ideal install why couldn’t they have used something like a high end soundbar. My son has a £1000 soundbar below his 65inch tv that has no base or and doesn’t use the TVs speakers. It sounds great, even when playing PlayStation games or films requiring surround sound and the speakers are tiny. Surely someone could develop this concept for cars?

Good idea! It would be a great idea if I'd thought of it lol. It's too simple. There has to be something wrong with it.... I think....

 

[Tokion]

I think Nova’s explanation above is really excellent, and also since my car still has not yet arrived, I have nothing to add (beyond what I have already said previously).

However, I do have a fact reminder:

The KEF Uni-Q speaker units are COAXIAL DRIVERS, which means that the tweeter is positioned at the center, so the midrange/woofer is surrounding the tweeter. A speaker that is designed like this will create a “point-source” of sound.

If you add tweeters higher up at the A-pillars or wherever, you defeat the design purpose of the KEF Uni-Q.

This is why my own effort will concentrate on improving amplifiers, wiring, grounding - but first and foremost removing and replacing the so-called “Fresh-Air” subwoofer at the rear. (But keeping the KEF Uni-Q drivers.) I am still thinking of what will be the best solution, but I am considering a very capable woofer from the German brand ETON in a custom made sealed box (with appropriate, new amplification). It is worth noting that the “Fresh-Air” subwoofer is not a KEF product, and neither are the amps and remaining electronics in the Emira. Most probably a new DSP system will also be required. I cannot go further until the car arrives.

 

[Speedy Emira]

Good idea! It would be a great idea if I'd thought of it lol. It's too simple. There has to be something wrong with it.... I think....

Ok, I should put a soundbar on the dash and Bluetooth Spotify from my phone to it. If it works I will sell them on the forum for £2500 each on a group buy deal and supply a 12v adaptor and the required specialist acoustic-compatible fittings (double-sided tape). The 2 models will be called SpeedySung and SpeedyOny.

 

[digilotus]

Thanks for sharing this video! Some great info in there.

Let's not forget that the center KEF speaker also has a tweeter, with sound frequencies bouncing off the windscreen towards the passengers. From first hand experience, the KEF system has lots of treble directed at ear level beyond what the door mounted speakers produce. It definitely does not sound flat or require any more treble arriving at ear level. In fact I reduce the amount of treble in the equalizer as the default setting is too bright for me.

It is a shame that they did not make use of the centre KEF speaker. Having a decent yet disconnected driver mounted in the dash would make me more annoyed than having "blank" tweeter grilles in the A pillars. Definitely a missed opportunity.

 

[Eagle7]

Ok, I should put a soundbar on the dash and Bluetooth Spotify from my phone to it. If it works I will sell them on the forum for £2500 each on a group buy deal and supply a 12v adaptor and the required specialist acoustic-compatible fittings (double-sided tape). The 2 models will be called SpeedySung and SpeedyOny.

I think you should mount it on the firewall behind the seats, right below the window. Call it the SpeedyBar, and display a graph that shows how it adds 5 hp because the sound coming from the bar is pushing the windshield forward.

 

[Speedy Emira]

I think you should mount it on the firewall behind the seats, right below the window. Call it the SpeedyBar, and display a graph that shows how it adds 5 hp because the sound coming from the bar is pushing the windshield forward.

Sounds like I have a new business partner in the making. We could call the company Smoke and Mirrors Racing.

 

[Eagle7]

Sounds like I have a new business partner in the making. We could call the company Smoke and Mirrors Racing.

We'd have to do mock-ups. Imagine the commerical; man sitting in the seat, turns on the SpeedyBar and his hair starts blowing forward. Takes his foot off the brake and the car starts rolling forward as Highway Star from Deep Purple is getting louder and louder on the SpeedyBar.

Slogan: You don't know what speed is until you've been to the bar... the SpeedyBar!

I guess we could include a complimentary hand mirror with the company name on it for guys and gals who need to fix their hair afterwards. SO much potential here!! lol

 

[Nova]

Nova, have you heard the system in the Emira? How long did you listen to it? When are you expecting to get your car? Are you getting a FE1 with the Kef system?

Building a system in a car is very difficult., I have done many in my time from BMW, Porsche, Audi, Lotus and many more Higher end cars. When I built mine in my Evora it came out pretty good and it was much better than the original system. We all know that the Emira has very limited space & is very similar to the Evora. I am a little surprised and annoyed that KEF allowed that to be the final product especially after hearing it in the Lotus SUV. SUV system was very nice, I was hoping the Emira even in its limit space would be at least 50% as good and IMO it’s not even close.

I have not heard the system in the Emira. I'm waiting for CARB approval like everyone else in the US for my FE 1.0, which as of now is still in England.

The concerns you indicated for the KEF system in the Emira are absolutely valid. A small vehicle like the Emira provides both pros and cons in terms of challenges. Pros being that the small cabin typically makes it *easier* to get good bass, and cons being the small cabin typically makes it harder to get deep expansive sound stage. I have posted many theoretical critiques of the OEM KEF system and while I'm reserving judgement until I actually hear it, my guess is that KEF was so limited in what they could do with the car that they sort of just became a parts supplier. I don't know who, if anyone, did the system integration beyond setting the crossover points and relative levels. Some simple signal analysis of the amplifier outputs would be very revealing in this regard.

The Eletre is a brand new design, which I guess really allowed KEF a lot more creative/design freedom to act as a proper system integrator.

 

[Nova]

I think Nova’s explanation above is really excellent, and also since my car still has not yet arrived, I have nothing to add (beyond what I have already said previously).

However, I do have a fact reminder:

The KEF Uni-Q speaker units are COAXIAL DRIVERS, which means that the tweeter is positioned at the center, so the midrange/woofer is surrounding the tweeter. A speaker that is designed like this will create a “point-source” of sound.

If you add tweeters higher up at the A-pillars or wherever, you defeat the design purpose of the KEF Uni-Q.

This is why my own effort will concentrate on improving amplifiers, wiring, grounding - but first and foremost removing and replacing the so-called “Fresh-Air” subwoofer at the rear. (But keeping the KEF Uni-Q drivers.) I am still thinking of what will be the best solution, but I am considering a very capable woofer from the German brand ETON in a custom made sealed box (with appropriate, new amplification). It is worth noting that the “Fresh-Air” subwoofer is not a KEF product, and neither are the amps and remaining electronics in the Emira. Most probably a new DSP system will also be required. I cannot go further until the car arrives.

One of the more useful piece of information I got out of Cambridge Audio's video, which they didn't mention, is that the OEM subwoofer looks to be a 6x9 oval unit with a 1-inch voice coil. There doesn't seem to be two drivers, so the "two driver" description we've seen is probably referring to a dual voice coil design instead. Previously I was thinking that there were two 10" units mounted back to back in a shared manifold. Frankly, I strongly doubt the ability of a single 6x9 driver in a infinite baffle configuration to produce good quality bass at sufficient levels in a car like this.

What would be ideal is if someone can reverse engineer the A2B bus and create a control unit that gives you full access to the digital audio stream. There are boxes like this for Ford and other brands, and people have "hacked" into Tesla's A2B bus, so we know it's possible. It's just a lot of work, though.

 

[Time2Fly]

Well I nominate you, since you even know what one is.

 

[Nova]

Well I nominate you, since you even know what one is.

I looked into this and it's potentially way more involved than I imagined. One can say the "easy" part is getting a A2B bus analyzer, which costs about $2800, reverse engineer the slave node configuration of the Harman amp/processor, and essentially program a new slave node that acts like this amp but provides digital/analog audio outputs.

However, it appears that the CAN bus may be involved for volume, balance, tone, controls as well as Bluetooth hands-free noise cancellation coordination.

That's just too much to get into...

 

[Shyatic]

With all the technical business I think I'll settle for the stock system until the warranty runs out, by then there will be some good upgrade options and a plethora of ideas around them.