Do I need room EQ?

[clausdk]

Finally got my PB12+ piano finish!

Holy cow what a big sub! They weren't kidding about the weight either. Almost hurt my back with this thing barely being able to get it out of the box singlehandedly. I was quite easy to scoot around the floor luckily and I tried 3 corners + middle next to coach. Best position was just beside the sofa left of the listening position. I tried using fase control etc, however didn't get any noticeble results. I tried differen crossovers and they changed little as well.

Here's the sub alone at 150 hz crossover and no EQ. I turned out that the initial corner where the CHT 10 was delivered next to nothing below 28 hz!! go figure!
graf-pb12+-before-eq-crosso.jpg

Here's the sub with 80 hz crossover and EQ:


Here's the sub + mains with EQ 80 hz crossover:
sub-+-mains-80-hz-with-eq.jpg

It's been more difficult to EQ the PB12+. I will work alot more on it though. I need more training using the EQ filters. I need to use less and be more effective with them.

Sound experiences(very initial observations):

* Movies
Well, my couch is shaking a whole lot more hehe - the CHT-10 wasn't a subwoofer that's my first response!

* Music
Blends extremely well with the mains. Calls no attention, appears fast and delivers what I should and no more.

I need to watch some full movies and alot more music and tweak a whole lot more before I can give any sorta of final conclusion.

For now I'm satisfied it's definately an upgrade from the CHT-10 without a doubt.

[brucek]

Here's the sub with 80 hz crossover and EQ:

Graphs 2 and 3 are identical. You have the mains on in graph 2 for sure....... You should start your EQ'ing with the mains shut off. Then when the EQ'ing is done, add the mains and check with the phase control for a smooth transition at ~80Hz..

Either way, that's a better response than the first plot.....

brucek

[Wayne A. Pflughaupt]

I tried 3 corners + middle next to coach. Best position was just beside the sofa left of the listening position. Here's the sub alone at 150 hz crossover and no EQ.

Holy cow! I’m typically not adverse to aggressive equalization, but that’s an unequalizable curve, as far as I’m concerned. I’m surprised you got end results as good as you did.

Your room isn’t all that big, at least based on the diagram you showed us at Post #4 way back on the 1st page. And it’s obvious that the brick-wall response at 30 Hz you had before isn’t indigenous to the subwoofer. This sub should have no problem hitting below 20 Hz in a 1700 cu. ft. room with little or no EQ down there. Obviously something’s amiss. Your picture makes it look like your room is a typical rectangular “shoebox,” with no openings. Is there something else we need to know and consider?

I’d be interested in seeing your corner graphs. I know you mentioned before that you and your friend “both agreed that the corner placement added most punch, however at the expense of a very uneven response curve.” But I can’t imagine response being more “uneven” than this! Very often what we find with corner placement isn’t necessarily the best response, but response that’s the most equalizable. Typically the best corner is the one with the longest lengths of interrupted wall in both directions, but according to your room picture, you have no shortage of those. Again, is there something about your room I’m missing? (I didn’t read each and every post from these four pages, so I might have missed something mentioned before.)

Don’t mean to deflate your balloon – just think you should be getting a lot more from this sub in this room.

I tried using fase control etc, however didn't get any noticeble results.

I’ve noticed that we hear that a lot, to the point that I wonder if the thing even works! In your situation, with the sub right next to the couch, it should make a difference. But maybe the distance between it and the mains is more than the phase control is capable of.

Regards,
Wayne

[clausdk]

First of all, love this forum

I edited the post above, it seems I've added the same graph twice, sorry about that, the sub with eq and 80 hz crossover should be there now. I did EQ the sub alone and made only minor changed after adding in the mains.

Regarding the room, here's a picture of the possible locations I've got to choose from:
Pos. 1: Seemed to be the best spot for the CHT-10 as the performance of the sub was down to 28 hz so I figured it all added up when the tests I did there for this sub rounded off at 28 hz.
Scarely enough so did the PB12+ in that corner, which left me dissapointed and puzzled!
Pos. 2: Had the best 10hz-25 hz response, but some hard dips around 40ish and 60ish.
Pos 3: Can't remember for sure, but do recall it being the least best of the 4 I tried.
Pos 4: Where the sub is now. Had decent response below 25 hz and only one serious dip.
I didnt save those graphs actually, perhaps I should've so I could show them, but what I found was that where the sub is now seemed to be the best comprimise.
About the room - added some more furniture but it's nothing I think could cause any problems really.
room.JPG

To be honest I was quite dissapointed because I wanted the down low frequency, was one of the reasons I upgraded to this sub and it seemed my room was eating them all up. I made the REW program (wonderful tool!) make a sin wave at 20 hz. I then proceeded to walk around the room with my SPL meter and surely there was alot of 20hz db going on! Just not at the listening position. I did this test to make sure the sub actually worked. Even 15 hz was noticeble at various spots around the room.

Here's some unwrapping pictures(don't mind the mess/cables and all the test material)!
Thats gonna break my back?
PB12+-pakkes-ud.jpg
So nice!
PB12+-pakket-ud,-how-nice.jpg
Corner at hifi
PB12+-corner-ved-anlæg.jpg
Current position
PB12+-corner-at-coach.jpg


I'm going to recheck something shortly and that is the cal. file for the SPL meter. I wan't to make sure its set correctly. Other than that I do believe im running the REW program accurately.

We're building ourselves a new house! here's a preview of what the living room will look like:
stue.jpg

It's bigger better and most of all, no immediate nabours! can't wait :=)

Oh yea! and btw, I REALLY did hurt my back on this thing, seriously....was alone handling it, holy cow....hope I get better today since I might wanna move it around and reinstall some cabling.

Lol, subwoofing is dangerous

PS: More on sound quality. Watched the "number 23" last night and the overall sound is alot more immersive, really. More punchy and scary. It is surely a step up from the CHT-10. I just wonder if I can get even more out of it of course.

[clubfoot]

I think sitting so close to the back wall is your main problem and check to make sure you don't have some type of "peak bass limiter" engaged in your processor, that drop off is too steep to be natural. As an experiment leave the sub where it is and take a measurement 2/3 of length (18') of your room between the table and the chair in your diagram and post the result.

[Wayne A. Pflughaupt]

That would more correctly be a high pass or rumble filter, but yes I would definitely check your receiver’s or processor’s menu for the presence of one.

Also, you might regret limiting your sub to one location in your new place, since you have no idea which position will perform the best. I’d run in-wall cables for at least 3-4 viable locations. That will let you use the one that ends up working best, without a visible cable draped across the floor.

Regards,
Wayne

[clausdk]

I'll double check the reciever, I don't believe any limiter is engaged. However there is such a feature in it I think.

Regarding my new home - I was trying to figure out how to hide the cables for the sub as I knew I couldnt guess on beforehand where I would perform best. Hmm I might just run cables for 4 spots then. I'll be sure to put electrical outputs in all corners too then.

Moving in about 1.5 months to a temperary home since my girlfriend got another job other side of Denmark so we'll have to stay there for 6 months and THEN my friend, THEN it's time for my to enter the REAL playground of subwoofing when I finally move into my own **** house!

Any of you ever lived in an apartment and then also at the same time love hifi? argh, it's frustration not being able to let it all loose if only for one song! My nabours are very patient though and I never got a complaint.

I am considering getting a better microphone as well. Been trying to look up some of the mics here on the site, but havent found one in Denmark yet, but there must be one around.

I'll try and work some more with it when I get some sparetime.

/claus

[brucek]

The microphone and its preamp that we recommend for the best response and price is the Behringer ECM8000 + Xenyx 802. They sell Behringer products in music supply stores where they sell guitars etc. Most cities have one of those shops.
We have a mic calibration file for it in our download section.

brucek

[JohnM]

You can also get a calibrated mic and preamp kit from IBF Acoustic, www.ibf-acoustic.com

[clausdk]

Small update. Moving in 6 weeks to a temporary apartment before our house is finished! I'll readjust once I use the sub in that room. Until then I'm going to use my current setup which is really good.

Enjoying movies to the full, can't wait until "300" comes out!

[clubfoot]

clausdk wrote:

Small update. Moving in 6 weeks to a temporary apartment before our house is finished! I'll readjust once I use the sub in that room. Until then I'm going to use my current setup which is really good.

Enjoying movies to the full, can't wait until "300" comes out!

300 is already out on DVD!

[clausdk]

Small update.

My Behringer 1124 won't turn on as of today! It's a disaster!

I was watching X-men the last stand yesterday and I agreed with myself that the bass was wonderful, tight and precise!

Today I tried it without the Behringer and believe me when I say this was like night and day. I think it's because I've been used to the bass with EQ on for some weeks now, then suddenly going back to non EQ'd you realise the difference. TO be honest the bass was boomy and loose and not detailed. In the scene where they practice in virtual reality there is a big "machine" of sorts and it tramps before Wolverine is trown at it. That tramp was really impressive with the EQ on but not it's nothing more than a boomy annoying experience!

Conclusion - I need my Behringer repaired ASAP!!!!