PSA Room Size Knob - Graph?

[Roen]

I'm looking to understand how the room size knob works on my S1500.

Does anyone have a graph showing a knob sweep of the room gain knob, with dB on the y and frequency on the x-axis?


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[lovinthehd]

Did you ask PSA?

 

[speakerman39]

I'm looking to understand how the room size knob works on my S1500.

Does anyone have a graph showing a knob sweep of the room gain knob, with dB on the y and frequency on the x-axis?


Sent from my iPad using Tapatalk

Why not give Tom V. a call or chat him directly on his(PSA) website? Tom is a very nice guy and would be more than happy to answer all of your questions. I owned dual S1500's and the room size knob basically tightens up the bass depending on room size and placement. That is how he merely explained it to me. However, my room is very small coming in at only 1,440 ft.^3. MLP is ~8' from my front-stage. Tightness and /or punchiness is what I wanted the most. The S1500's did not disappoint! Just saying..........


Cheers,

Phil

 

[mike c]

basically, you get more low end output with the larger the room setting.
i consider the "small" room setting to be some form of neutering.

i'll consider it if my room was less than 1k cubic feet in volume.

 

[Roen]

I only can raise the room gain a smidge before the bass sounds bloaty.

1.5k ft^3

 

[mike c]

I only can raise the room gain a smidge before the bass sounds bloaty.

1.5k ft^3

bloaty is very subjective. the right thing to do is to find out your room frequency response, so you'd have the correct next step.

barring that, yes, use the room gain compensation to "try" and see if the bloatiness goes away. (adjusting towards small)

 

[TheWarrior]

The room is firmly in control of bass response below the transition frequency where bass remains omni directional, gaining more forward bias as frequency increases. When the wavelength matches room dimensions (including 1/4 waves) it can become what we know as Room Modes and/or Standing Waves as the sound wave gains amplitude from the boundary interaction, or is out of phase at the listening position and needs amplitude increased. Peak or null, its a mode.
20 hz = 56.5 ft 100 hz = 11.3 ft

Options:
1 - run 'Room Correction' from all sorts of positions until you find a setting you can live with
2 - Buy more subs to balance bass response seat to seat
3 - Learn to manipulate DSP by adding filters to the corresponding frequencies as evidenced by your own 1/24 octave measurements with the appropriate amplitude and bandwidth (Q) to cancel out the resonances.

 

[ATLAudio]

I'm looking to understand how the room size knob works on my S1500.

Does anyone have a graph showing a knob sweep of the room gain knob, with dB on the y and frequency on the x-axis?


Sent from my iPad using Tapatalk

Tom has a graph showing this. He sent it to me once, but I can't find what I did with it. Call him and he'll email it to you.

That knob is a Low-Shelf adjustment allowing the user to best match room gain to the sub.

A 1500 cubic foot room is a very small room, so it doesn't surprise me that adjusting it more than a smudge gives "bloat." I'd defeat the know (ie smallest setting), then run room correction.

 

[Roen]

Tom has a graph showing this. He sent it to me once, but I can't find what I did with it. Call him and he'll email it to you.

That knob is a Low-Shelf adjustment allowing the user to best match room gain to the sub.

A 1500 cubic foot room is a very small room, so it doesn't surprise me that adjusting it more than a smudge gives "bloat." I'd defeat the know (ie smallest setting), then run room correction.

Why running it at the smallest setting, and then run YPAO?

Why not run it at the largest setting with YPAO?

 

[ATLAudio]

Why running it at the smallest setting, and then run YPAO?

Why not run it at the largest setting with YPAO?

As with any room correction device, they operate on a "help me, help you" philosophy. Don't make them fix what you can fix yourself, so they can focus on what you can't help, like your room modes. At lower frequencies an REQ, like YAPO is very subject to mic placement, and can very well make it worse. Give YAPO the cleanest, and easiest work possible.

That said, based on your room dimensions you're getting room gain right at, or just below the +-3 dB roll off with that knob fully defeated at small.