On baffle step and SPL

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Hello,
I am playing with simulation of real speaker system including baffle size and room effects. Many questions arose...
I clearly loose 6 dB in deep bass so I must make mids and twetter less sensitive to make SPL flat.

But:
1. in real living room reflections from the floor (mainly) and also from rear wall return back some decibels
2. if I see real measurements of commercial available loud speaker I dont know other parameters of measurement except 1W/1m. It is measured with big additional baffle? They removed any reflections? What are standard measurement conditions?
3. if baffle step is there (no additional baffle added) it is hardly believed that someone can achieve 96dB sensitivity and 20Hz +-3dB (HiFi sound)
4. every little change of speakers position in the room, or placing in different room completely change the sound. It makes sense to buy 20t Eurs loudspeakers for standard living room?
5. as in previous item it makes sense to playing with drivers position and crossover parameters when I dont have exact knowledge about room parameters?
6. It makes sense to go into shop's listening room to choose loudspeakers? That room is for sure different from in house room.
 
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In real terms more than 4dB of baffle step is not necessary. Where we live the rooms are usually smaller so 3dB ends up being a good target value. You will see many speakers when measured in-room exhibit a bump in the low and mid bass, formed by very enthusiastic baffle step. Some of this is mitigated by near wall reflection in the midrange and lower treble off harder surfaces in a semi-reverberant room.

96dB at 1w/m is not a very good description of overall speaker performance. Linearity, bandwidth and polar response also define to a large extent the quality of the product. You should also take care to match your speakers to the kind of room and your listening preferences.

Also, please don't capitalise your posts. Capitals is akin to shouting when posting, you can use the bold, italic and underline in the quick reply box, or like us old-timers, use asterisks to *emphasise* your words. To fix your post if you want to, press the "report" button below your username and the mod crew will take care of it.
 
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in real living room reflections from the floor (mainly) and also from rear wall return back some decibels
Yes. This does not mean you can use less compensation. It means your response is mixed up. Normally you try to find a room placement that lessens this. Sometimes it is enough and sometimes it isn't.
with big additional baffle?
Yes.
 
Yes. This does not mean you can use less compensation. It means your response is mixed up. Normally you try to find a room placement that lessens this. Sometimes it is enough and sometimes it isn't.

Yes.
Does exist a standard how to measure SPL (to compare comparable)? If I understood well measurements are based on 2Pi radiation. How they technically make commercial measurements that excludes baffle step?
 
diyAudio Moderator
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Yes. Here is an example. It isn't perfect but it is useful.
 

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I have a question.
It is about a two way WAW design..one woofer and one full range driver. If i take the woofer's spl measurements mounting on the baffle, then net spl frequency response will be after baffle step loss..am i right? If yes ..then do i still need to worry about baffle step compensation while designing crossover with this measured spl frequency response for the woofer?
If i would still be requiring baffle step compensation ..then why..can someone explain please?
 
diyAudio Moderator
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No, you don't have to add compensation, I think you understand that you are correct about that. Your filter will have this when you design it.

Your baffle 'loss' will be 'found' by the walls, so you cannot call it a loss. You have to be careful how you place your speaker.
 
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