Room SIM improvement

Discussion in 'Official REW (Room EQ Wizard) Support Forum' started by Hank74, Jan 7, 2019.

  1. Hank74

    Hank74 New Member
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    Hello everyone,my first post here.

    I use REW since several years,and I really like the Room Sim feature.
    It's really a great tool.I would like to suggest/request an additional option inside it.

    I think a huge improvement would be to have the possibility to visualize SBIR only,with the same 3D behaviour.
    I mean the possibility to move head/speaker in the room as already,but choosing to visualize only Modes,or only SBIRs,or both in action.

    Having also visualization of lines of SBIR path would be even a really cool thing.

    I have an homestudio for audio production/mix/master,already treated with broad and Low specific treatment.
    I can do the math for finding SBIR frequency and paths by myself,but seeing how good REW RoomSim is,it would save a LOT of time to have these features integrated.

    Maybe they are already integrated in REW and I missed,if so please let me know.

    Anyway,REW is really a cool software,keep up the good work guys.
     
  2. Hank74

    Hank74 New Member
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  3. John Mulcahy

    John Mulcahy REW Author

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    I added that to the todo list for the room sim when you posted it, but I don't know when I'll get to it. There is a lot on the todo list. The room sim responses include boundary effects, isolating them is possible using a different method than that used to produce the complete response (an image source method including only the first order reflections) though they also become apparent if a set of measurements from a range of listening positions are averaged. I'm not so sure what value seeing the boundary effects alone really adds though.
     
  4. Hank74

    Hank74 New Member
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    Thank you for the reply.

    Well,I am talking about just one listening position,the sweet spot.

    The value added is that sometimes,when you are "hunting" for SBIRs,it can save time if you can identify quicker who is who,and a room sim showing just them would help.
    Even better would be lines showing the sound path of the SBIR.
    I am talking about room acoustic correction,low tuned absorbers,and positioning of them.
    For mixing/mastering pourpose rooms.
    Thanks
     
    #4 Hank74, Jan 30, 2019
    Last edited: Jan 30, 2019
  5. luegotelodigo

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    I think SBIR calculated by the image-source method for low order reflections is not so useful for different reasons depending on frequency but the right surface absorption coefficient helps improving the results a lot.

    That coefficient can be estimated from RT or alfa Sabine and Volume and ideally should be frequency dependent. I like the way room sim works and improvements can lead to complexity meaning unexperienced users getting wrong results.
     
  6. Hank74

    Hank74 New Member
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    Can you explain these reasons?

    Because I don't get your point.
    Can't see how one more feature (selectable on user needs) would increase complexity.
    If you need it you use it,otherwise you don't.

    But maybe I am missing something.
    I am requesting those features on the pourpose to locate the points where this or that sbir occours,and so where to place the right absorber.
    But maybe I am also not expressing myself adequately.Not a native english speaker
     
    #6 Hank74, Jan 31, 2019
    Last edited: Jan 31, 2019
  7. luegotelodigo

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    What room sim displays now is also SBIR based in easy assumptions. What you want is the same but calculated with a number of reflections. What I understood is you want to use it for low frequency tuned absorbers...

    1) They are reactive, and most of users don't know their acoustic impedance
    2) They don't behave as rays, so you don't have specular reflections
    3) You won't fill the whole wall so you should input the system where they are

    Usual expensive raytracing simulators can't deal with this problem and IMHO the best approach are numerical methods as FDTD, FEM, BEM but defining the boundary conditions is a challenging task.
     

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