b&k room resonace

thuchien

hi,

my b&k preamp has room resonance function but in the manual doesnot explain very detail for beginer like me to understand. I need some one to show me step by step on how to setup so i can take full advantage of my preamp.


if my slp meter doesnot have 75dB set only 80 or 70 then how can i set to 75dB

thanks a lot.

MADGSF

Can't help you with the Ref 50 unfortunately.

However for your sound meter, if it's a Radio Shack analog meter set it to 80. The 0 point is 80 dB and -5 down from 0 is 75 dB. Conversely the +5 point above 0 is 85dB

Gaara

Do you mean the notch filter that is explained on page 27 and 28 of your manual? If so I have used this and should be able to walk you through it. I do not have the S2 Ref 50 though, I have the older S1. Only difference in respect to the notch filters is I only get one, and you get three.

Jared

thuchien

Gaara,
i have s2, so how do you find the notch filters?

thanks

polkatese

How to setup Notch Filter (for the first Notch, repeat to find the other two notches)

1. You need a rat shack meter, patience, pen & Paper (BTW-this whole thing is done just like setting your speaker levels)

2.In the speaker EQ menu in the set up select "NO" for THX boudary comp (which turns things down at 60hz and 20hz...why would anyone want to get rid of 20hz?)

3. Next I would select the freq which your x-over point starts (i.e. 80hz for THX)

4. Play test tone at that level (I just used the first one offered and write down the results. turn it off after you write it down before selecting the next.(it is really not necessary that you turn it off...you can go straight to the next freq once written down)

5 Go back to the freq field and go down a notch (it goes in 2's i.e. next would be 78hz)

6. continue steps 4 and 5 until you hit 20hz (the bottom)

7. More than likely you'll see a pattern where there is a number of freq. which are much higher than the rest of the freqs and one "notch" that is the highest. This will usually be in the boomy ranges 60-35hz.

8. select this frequecy as the "notch" -there is a field to select the notch.

9. next you need to select the bandwidth width (i.e 30hz to 40 hz if that was the width of the hump). The more of the freq that are too high, the wider the width is to set ,if its only 2 or 3 offender freqs then make it more narrow.

10.From this point start at -3 to bring the area of the hump DOWN (NEVER RAISE THE LEVEL/This will only compremise your sub performace)

11. Go back now and play the trouble freq. areas again and see if it was enough (if not keep droping by -3s) to bring the numbers close to the majority of the readings (write down findings for reference)

12.Thats it (hope I wasnt too confusing)... -exit the menu and reset your sub level and enjoy!

McLoki

thuchien wrote:

if my slp meter doesnot have 75dB set only 80 or 70 then how can i set to 75dB.

Easy thing to do is just set your preamp at +5 (rather than zero) and calibrate to 80db.

(you can also set your preamp to -5 and calibrate to 70db but you will start to be effected by ambiant noise if you have a loud house or not well soundproofed room)

Michael

Gaara

Beat me to the punch. The only additional recommendation I would have is to make a graph in excel or type up all the frequencies in a word document so it is easier to write the values down. You could start at 80hz and work your way down to 20hz writing all the values on the left hand side. Then you could label all the columns like "original" then "1st filter" and so on.

I also would recommend doing these one at a time. If you have two notches to take care of take care of the first then the second. You wouldn't want one filter to adversely affecting the other...which you wouldn't realize if you did both at once but would if you did them one at a time.

Just take your time, it will be worth it in the end.

Jared