REW First Measurements and Advice Please

[vmaharaj]

I have finally hooked up my BFD with all my gear (Edirol UA-1EX soundcard, REW, ECM8000, Xenyx 802) and took measurments after following all the advice in the BFD guide, REW forum, etc..

All measurements are with only the subwoofer (Polk Audio PSW505):

Measurement 1 - Soundcard Calibration:


Measurement 2 - System as is:


Measurement 3 - First attempt at EQ:


I used the following filters:


Obviously I have numerous questions:

(1) Is what I have done acceptable in terms of good EQ practice?
(2) I could not get the BFD uploaded via Midi so I programmed it manually, is this ok? Is there a solution to get Midi working so it will not be too much of a pain entering the filters?
(3) I connected the BFD to my AVR and sub as advised in the REW cabling guides. I bypassed the filters by holding the In/Out button until it started to flash. I pressed the button on the back of the BFD to the IN position. At first I could not get any response from the BFD even with filters uploaded. Before and after measurements were exactly the same. I could only get the BFD EQ to work/respond with In/Out button not flashing! What could be the issue? I am under the impression that the In/Out button must be flashing for it to EQ....
(4) After getting my filters to work I had to adjust the gain on the subwoofer using the set target levels as a guide. I did this by adjusting the gain on the sub, testing the target level, readjusting until I matched it to the target level in the first graph. Is the ok?
(5) Any comments on the soundcard calibration?
(6) Finally, what do the graphs look like and can I make any improvements?

I appreciate any help, advice, criticism...

Thanks...

[brucek]

(1) Is what I have done acceptable in terms of good EQ practice?

No, the gain filter of +12dB at 34Hz is a no-no.

(2) I could not get the BFD uploaded via Midi so I programmed it manually, is this ok? Is there a solution to get Midi working so it will not be too much of a pain entering the filters?

Check the firware revision of your BFD. Must be V1.4. The previous V1.3 didn't allow midi operation correctly. Check firmware from the front panel. Or you can just enter the filters by hand. I do..

(3) I connected the BFD to my AVR and sub as advised in the REW cabling guides. I bypassed the filters by holding the In/Out button until it started to flash. I pressed the button on the back of the BFD to the IN position. At first I could not get any response from the BFD even with filters uploaded. Before and after measurements were exactly the same. I could only get the BFD EQ to work/respond with In/Out button not flashing! What could be the issue? I am under the impression that the In/Out button must be flashing for it to EQ....

Flashing means the filters are bypassed and the VU meters are monitoring the input level.
Off means the filters are are bypassed and the VU meters are monitoring the output level.
On means the filters are are engaged and the VU meters are monitoring the output level.

(4) After getting my filters to work I had to adjust the gain on the subwoofer using the set target levels as a guide. I did this by adjusting the gain on the sub, testing the target level, readjusting until I matched it to the target level in the first graph. Is the ok?

Once your filters are engaged, adjust the sub level with the sub amp volume using your receivers internal test tones as you normally do.
If you want to use REW, go through the standard calibrate and setup to 75dB (with sub and mains on) and then use the sub amp it to balance levels between the mains and sub.

(5) Any comments on the soundcard calibration?

Looks fine.

(6) Finally, what do the graphs look like and can I make any improvements?

The raw graph shows a fair peak at 60Hz. Move the sub around first to get the best response, then think about equalizing.

brucek

[vmaharaj]

Thanks for that.
I cannot reposition my sub due to room constraints and WAF (big issue).
I only added the +12dB gain after looking at Wayne's posts on house curves where he said that:
"Don’t be afraid to apply some boost to a depression, if needed. This is much preferable from a sound-quality perspective than applying a multitude of filters to bring everything else down to the level of the depression. As I mentioned before, using multiple filters for level adjustment is poor use of an equalizer."
Are you advising that I must only cut all the filters to get to the house curve at a lower target level and then add gain to get to the 75dB balanced position?

About the BFD, I found that I could only get the EQ to work with the in/out button set to onall the time. Is this correct or incorrect? If I had the in/out button flashing the measurements were all the same, that is with EQ and without EQ. I have my AVR subwoofer pre-out going to the BFD Input 1 and then the BFD output 1 going to the subwoofer.

Best regards...

[brucek]

apply some boost

My emphasis added......

Are you advising that I must

Simply cut the big peak at 60Hz and perhaps a bit at 80Hz.....

I found that I could only get the EQ to work with the in/out button set to on all the time. Is this correct or incorrect?

That is what I wrote above.

LED Flashing means the filters are bypassed and the VU meters are monitoring the input level.
LED Off means the filters are are bypassed and the VU meters are monitoring the output level.
LED On means the filters are are engaged and the VU meters are monitoring the output level.

brucek

[vmaharaj]

Thanks, I will try it later. Cannot wait to go home and play some more. Your help is truly appreciated...

[Wayne A. Pflughaupt]

vmaharaj wrote:

(1) Is what I have done acceptable in terms of good EQ practice?

I only added the +12dB gain after looking at Wayne's posts on house curves where he said that:
"Don’t be afraid to apply some boost to a depression, if needed. This is much preferable from a sound-quality perspective than applying a multitude of filters to bring everything else down to the level of the depression. As I mentioned before, using multiple filters for level adjustment is poor use of an equalizer."

The main problem is that your sub position is giving you very poor response, so poor that it's practically unequalizable. As you can see from your filter chart, it's going to take some drastic equalizing to get anything resembling good response. This is going to eat up lots of headroom, any way you cut it (no pun intended). Whether or not that's a problem will depend on how capable your sub is and the size of the room it has to fill, but if you end up with your sub making rude noises during bass-heavy passages, you'll have to scale back on the amount of equalizing.

Regards,
Wayne

[vmaharaj]

Hi Wayne,

I figured (and accepted) that my sub (Polk Audio PSW505) was not up to my room. It is corner loaded at present with a room volume of 2900ft^3 to drive. I am waiting for my dual subs (AV123 MFW-15) to arrive and then I hope it will be much better. I listen at 65dB when viewing movies so I think I am not pushing things too much. I am going to drop the filter at 34Hz down though just to be safe.

What type of house curve should one use when listening to music? Is it the same as the hard knee curve?

Also, in your opinion, am I using REW/BFD correctly?

Thanks and best Regards...

[Wayne A. Pflughaupt]

What type of house curve should one use when listening to music? Is it the same as the hard knee curve?

I use the same hard knee curve for all my listening. Other people prefer something different for movies vs. music. It's all a matter of personal taste.

Also, in your opinion, am I using REW/BFD correctly?

Yes, it looks like you have the hang of it. The main problem with your 34 Hz filter was that it was essentially utilized as a broad level adjustment which, as I noted in the quote you highlighted in Post #3, is poor form. Hopefully your new subs will have more output below 60 Hz in that location...

Regards,
Wayne