Kef LS50 foam plugs

[ErLan]

Hello smart people,

I would like to pick your brainbon the following....

I tried to quantify the impact of the LS50 foam plugs on the sound low end.

My speakers are placed close to wall (speaker back is <20cm from front wall -> a given constraint); where - according to KEFs manual - plugs are recommanded.

My LS50s are 2nd hand, and I do not have the original plugs as such I shaped two pairs of plugs: (a) foam, (b) rubber.

Surprisingly, when taking a MMM measurement (REW). I see no difference in the measurements between the non-plug, and either foam or rubber plug.

Any idea what may be wrong in my 'setup' and/or method?

 

[fpitas]

I don't know why you can't measure it. But were it me I'd just go with the way it sounds best

 

[ErLan]

Frankly, both sounds identical; however I hoped that plugs will somewhat control low end slope which will help me to integrate a sub (currently measure slope of speakers is close to 42dB/Oct, and the transition from mains to sub using the speaker natural rolloff sounds too stressed).\

 

[somebodyelse]

Are the LS50s driven full range, or high passed, and if so what frequency?

 

[HarmonicTHD]

Hello smart people,

I would like to pick your brainbon the following....

I tried to quantify the impact of the LS50 foam plugs on the sound low end.

My speakers are placed close to wall (speaker back is <20cm from front wall -> a given constraint); where - according to KEFs manual - plugs are recommanded.

My LS50s are 2nd hand, and I do not have the original plugs as such I shaped two pairs of plugs: (a) foam, (b) rubber.

Surprisingly, when taking a MMM measurement (REW). I see no difference in the measurements between the non-plug, and either foam or rubber plug.

Any idea what may be wrong in my 'setup' and/or method?

Did you search the Kef page. Often times they provide measurements (or white papers) on their speakers which quantify these effects? At least they do for mine. (Might not be in this case but worth a try before speculating or struggling with your own measurements. However it should be measurable. Again it do so for my KEFs. Maybe try the non MMM version. )

 

[ErLan]

Are the LS50s driven full range, or high passed, and if so what frequency?

I measured those 'full range'.

@HarmonicTHD, thanks for the suggestion, i will look on KEFs home page.

 

[ErLan]

Hi, I repeated the neasurement using swipe, and now differences in low end are clear both 'visually' and sound.
Consider case as closed

 

[aarons915]

I measured the Q150 in my room years ago to see the difference the plugs made, should be very similar to the LS50.

 

[juliangst]

I'm also using my LS50 with the foam plugs because of the short distance to the wall. But I can definetely hear and measure a difference with and without foam plugs.
Here are some old measurements of the different configurations:

 

[ErLan]

Thanks all for sharing, I was able to replicate the results (means low end boost with plugs).