STF-2 freq response curve

[davedawg]

hey everyone,
hope this is the best place to post this. i have just now started playing around with my STF2 and recently did a FR curve. just interested in getting some feedback. this was done with 1/6 octave test tone disk from "Acoustic Elegance" for what it's worth. room dimensions are about 13'(deep) x18'(wide) x8'(high). i'm jsut concerned about the low end of hte curve, <40Hz. it seems a little weak. i realize the room will play a huge role in the curve, but is this consistent with room effect? thanks in advance.

dave

p.s. ignore the "SVS 22-31" lettering at the top, i added my graph to an existing spreadsheet. oops!

[Josuah]

May I ask what you used to get the SPL input to your computer?

[davedawg]

May I ask what you used to get the SPL input to your computer?

sure. a radio shack analog SPL meter mounted on a tripod at the listening position pointed at the ceiling.

[cschang]

Did you use the correction factors for the Radio Shack meter?

[DavidD]

Did you use the correction factors for the Radio Shack meter?

Good question. The meter has a documented error as frequencies descend below 100 Hz.

[davedawg]

Did you use the correction factors for the Radio Shack meter?
i did use a correction table.

[Lwang]

Looks more like a room suckout at 28hz. Otherwise, the curve just gradually slopes downward

[tafguy]

sure. a radio shack analog SPL meter mounted on a tripod at the listening position pointed at the ceiling.

Though I haven't used it, but you could also use the Radioshack digital SPL meter's AC output to feed sound data to line-in terminal of the PC's sound card and use a real-time sound analyzer software to plot sound data. Have anyone tried this feature?

[davedawg]

Looks more like a room suckout at 28hz. Otherwise, the curve just gradually slopes downward
i guess my point is that my curve looks NOTHING like the uncorrected curve here (http://www.hometheaterforum.com/htforum/showthread.php?s=&threadid=209418). this is the only FR curve i can find of the STF2 and it is pretty darned flat. mine isn't. is this totally due to my room or is my STF2 not up to snuff? seems that if it was due to the room, the curve would have peaks and valleys rather than just gradually sloping downward like it does.

dave

[Pete_Hsu]

Good evening Dave,

The frequency response graph you are looking at in the link above is showing frequency response of the STF-2 outside, without room interaction. Notice that it is very flat. In room, the frequency response will always be affected by the room itself!

Feel free to email Dr. Hsu for specific recommendations on setup and placement.

Hope this helps

Sincerely,

[davedawg]

Good evening Dave,

The frequency response graph you are looking at in the link above is showing frequency response of the STF-2 outside, without room interaction. Notice that it is very flat. In room, the frequency response will always be affected by the room itself!

Feel free to email Dr. Hsu for specific recommendations on setup and placement.

Hope this helps

Sincerely,
peter,
thanks for the reply. so my room is the culprit. i plan on getting a BFD to flatten this out. thanks again.

dave

[Lwang]

You shouldn't equalize a downward sloping bass response. All you do is drastically restrict its headroom. What you should be doing is try to find the optimal placement in which you would get better bass while minimizing peaks and nulls.

[davedawg]

You shouldn't equalize a downward sloping bass response. All you do is drastically restrict its headroom. What you should be doing is try to find the optimal placement in which you would get better bass while minimizing peaks and nulls.
i'll try moving the sub around some. thanks for all your help!

[Josuah]

Though I haven't used it, but you could also use the Radioshack digital SPL meter's AC output to feed sound data to line-in terminal of the PC's sound card and use a real-time sound analyzer software to plot sound data. Have anyone tried this feature?

This is more of what I was leaning towards with my question. :)

[tkc]

Though I haven't used it, but you could also use the Radioshack digital SPL meter's AC output to feed sound data to line-in terminal of the PC's sound card and use a real-time sound analyzer software to plot sound data. Have anyone tried this feature?I know this is an old thread, but if anyone is interested, I have used the output from an RS analog SPL meter to serve as input to ETF to plot in-room frequency response. It takes about 5 seconds of a broadband signal to generate enough data for a curve that closely matches that generated by painstakingly using individual sine tones.