Beolab 5 Calibration?

Hi All,

I've been reading alot recently regarding Beolab 5 speakers, and interested in the calibration of them.

I've read the speakers will reduce the bass if calibrated either in a corner or in a small room, i've read that people have emptied the room to make the lab5's increase the bass level, then put the furniture back in.

I've also read that if you put a coffee/tea mug around the microphone when it extends, the speaker thinks it's in a massive room, so the bass will be louder??

Also someone took them outside and performed a calibration in their garden?

Has anyone used a mug if they want more bass??

I know if using powerlink you can just increase bass on your music system, but that's not ideal.

Interested to hear any of your experiences.

Paul.

Hi Paul,

The basic philosophy and the implementation of ABC in the BeoLab 5 is to compensate for the radiation resistance "seen" by the speaker. To make a long story short, this may result in a reduction of magnitude at some frequencies (which are naturally boosted by your room) and possibly increase the magnitude at others.

If you calibrate the loudspeakers in a room that is different than the one you are using to play music (say, by removing the furniture, or calibrating in your back yard, or with the microphone in a coffee cup or a sock) then you will create a filter is certainly different than the one you would have gotten without the customisation, but not one that is better. All you have after doing this are (1) your original acoustical problem caused by your actual listening room and (2) an additional problem which is the correction for a different acoustic space like a coffee mug.

Generally, in cases where the low frequencies are extended in time (better known as "ringing" caused by resonances), this can result in a perception of "more bass" - but that perceived increase is due to the extension in time, not an simple increase in magnitude. ABC will reduce the effect of this ringing - and this may be perceived as resulting in a loss of bass in some cases - but it will also be more controlled in time (which may be perceived as having more "punch" for example)

If you wish to disable ABC, you can do so by starting the measurement procedure (press on the top button on the BL5) and hold it in until the measurement procedure aborts. This will clear the ABC filter.

If you just want more bass, then you should do this at the source, and leave the ABC to correct the averaged time response of the room. Please don't create an ABC filter for a coffee mug... :-)

Cheers
-geoff

Geoff  I have too much bass,is there a  way to reduce the bass with the calibration?

Hi Koning,

Sorry - there is no way to "tweak" the ABC calibration. So, if you want less bass, you'll also have to do that in the source.

Cheers
-geoff

 

Hi Geoff,

Sorry to sidetrack the thread, but have any figures been calculated for the processing latency of Beolab 5 speakers when used via the analogue (RCA) inputs please?  I was speaking to one of the stores today and they had delay problems (as you predicted in one of our other discussions) when trying to play live sound from musicians through Beolab 50s.  I had suggested trying Beolab 5s instead, as I seem to recall Dave Moulton mentioning to me about a decade ago that he used Beolab 5s as live monitors in his own recording studio.

I suspect that the ABC process within the Beolab 5 should result in some amount of latency, although I suspect this could be quite small due to the limited frequency range involved.  Any thoughts please?

Kind regards, Steve.

Hi Steve,

The latency of a BeoLab 5 from line in to analogue out is just under 4 ms - equivalent to a distance of about 1.4 m. This is with or without ABC.

The latency modes of the BeoLab 50 and 90 are 25 ms and 100 ms - much too long for live sound.

However, I would be careful about using any wide-dispersion loudspeaker for live sound due to the increased risk of feedback.

Cheers
-geoff

 

 

Thanks Geoff!

Kind regards, Steve.

Hi Geoff,

Thanks for your initial reply, very interesting on the Beolab 5 ABC.

I have been reading alot of your B&O technical blogs on loudspeakes and i'm staggered how complex and technical the art of producing a good sounding loudspeaker is.

Thanks very much for your input, greatly appreciated.

Paul.

 

Hi Paul,

Thanks! Glad to hear that someone is reading the stuff that I'm writing - and that it's useful! :-)

Cheers

-geoff

Hi Geoff,

I see that you Write: "If you wish to disable ABC, you can do so by starting the measurement procedure (press on the top button on the BL5) and hold it in until the measurement procedure aborts. This will clear the ABC filter."

Will this disable the ABC from the signal pathway entirely, letting me hear how the speaker performs with no active correction?

I have a pair of new Beolab 5 final editions, and they are way much more bass light than my former Burmester high-end system was. What is your experience when it comes to break in? Do the bass respons change much after playing them for a while?

 

I also see that other forum members have experienced weak bass response when bl5's are placed on a wooden floating floor that absorbs quite a lot of bass energy. Maybe they can perform better if placed on spikes and/or a concrete/granite shelf?

Thanks hugely in advance for your reply, it is really cool that you are active on this site.

 

Regards

Oyvind Lie

Norway

Hi Oyvind,

That is an interesting thought.  I'm a great believer in using concrete blocks to give a solid and stable base for speakers, especially on floating wooden floors.  I have this arrangement with my Beolab Penta 3 speakers in my workshop, each speaker sits on 4 x 25Kg dense concrete blocks, which gives the added bonus of raising the tweeter height by approx. 30cm, as well as greatly improving the bass weight and definition.

Whilst Beolab 5 should be able to compensate for many room issues, giving them the best possible starting point (ie. good positioning and a firm, solid placement on the floor) should always be a positive step in my view.

Kind regards, Steve.

Iam in the opposite situation, my floor is pretty solid wood and my new bl50's vibrate my neighbours wall next to me. Fortunately nobody lives below me so today i bought some firm rubber tiles to see if that makes a difference. My old bl2 was set way louder and it never bothered her, but then again that stood on the standard rubber "donut". I'll place them under the bl50's tomorrow and see what happens