Brand New NSD Pre and Post EQ First Pass

**azjimmy** · **07-25-06, 08:23 PM**

Hello all,
Just noodling around with REW today, post NSD driver upgrade on my PB12ISD/2.
I ahd a few issues with REW getting a good input volume, so I had to jack the volume on my receiver to +12.5. I think it might have to do with the deivers for my soundcard (Audigy 2 ZS Laptop PCI card). I'm still working that out.
These measurements were taken using my R/S meter. Next time I'm going to do the ECM8000/UB802 combo. I was just feeling a bit lazy.
news nsd's no filters.jpg
This is Pre-EQ

news nsd's with filters.jpg
Post EQ

REW Came up with 6 filters. I added 3, one at 22 Hz to tame a bit of that hump,one at 58HZ to give a slight boost and one at 87 to do the same.
Here are my filters

FRQ Gain BW
1. 160 +8 -8 2
2. 20+8 -3 4
3. 125-4 -6 1
4. 100+8 -5 1
5. 63-8 5 2
6. 80-9 -6 9
7. 100-2 -6 7
8. 125-6 -4 1
9. 80+4 6 1

Comments? Suggestions?
Thanks
Jim

**Sonnie** · **07-25-06, 09:51 PM**

Hey Jim... you bout don't need a BFD. Excellent pre-eq'd response.... one of the best I've seen. If it wasn't for that little pesky peak at 72hz... you'd be set.

You might check it with your mains and see if that little blurp at 140-150hz causes any cancellation issues with your mains.

**brucek** · **07-26-06, 04:49 AM**

Quote:

you bout don't need a BFD. Excellent pre-eq'd response

That's for sure. I would have someone turn your filters on and off for a blind test to see if you could actually tell the difference.

Then I'd remove the BFD.

brucek

**Sonnie** · **07-26-06, 07:13 AM**

Seems like we've got someone lookin' for a used BFD... I sense one coming up for sale.

**azjimmy** · **07-26-06, 03:41 PM**

OK,
I got off my **** and got out the mic and mixer. I ran this one with the front left main connected. I didn't pull the BFD out of the loop, just switched it to bypass. I did re-calibrate the sub to the system with no filters.

7_26 no filters + mains.jpg

It's a little worse. I have a huge hump from 60-90 and a couple of drastic suck-outs over 100 and some smaller ones at 28 and 58.
I bet alot of this is room placement/room treatment.
Jim

**Sonnie** · **07-26-06, 04:01 PM**

Where's your crossover set between your sub and mains?

I think your sub level is way too low in relation to your mains.

**azjimmy** · **07-26-06, 04:13 PM**

Ooops
I forgot I had a door open...here it is with all doors closed
7_26 no filters + mains.jpg

Jim

**azjimmy** · **07-26-06, 04:20 PM**

Sonnie,
I have it crossed at 80Hz, mains set to small. I set the level with the Rat Shack meter to 75 db like the mains. I always figured that that would bet 2-3db hot, given the low leveel error of the SPL meter. Am I bass-ackwards on that?
I do see what you mean, though. My level with the sub should be much higher...
My mains are JBL S38II's. They are rated to 45Hz.
Thanks for the help BTW...
Jim

**Sonnie** · **07-26-06, 04:39 PM**

Generally speaking I think most people will like a much hotter low end response, probably at least 10db hot and sometimes more. I'm not referring to a house curve for your bass response, but rather more of a whole house curve.

We generally speak of house curves for our bass response only around here... gently rising 8-10db from 80-100hz to 30-40hz and leveling off on down to 20hz and below. Even if we were to keep that area flat, I would believe a hotter overall bass response would be better.

Wayne wrote a pretty good article on all this here.

I can't say everyone would necessarily like it this way, but it seems to be more popular and natural for most people.

**azjimmy** · **07-26-06, 05:19 PM**

Ok,
I adjusted to sub level to be more in line with my mains. I think this a bit closer to what you were talking about.
7_26 no filters + mains.jpg

This is with it crossed at 60...

7_26 no filters + mains 80 hz.jpg

And at 80...certainly less of dip at 80.

7_26 no filters + mains 100 hz.jpg

Looks like that dip almost goes away at 100. I dunno. now I feel like I'm shooting in the dark

Jim

**azjimmy** · **07-26-06, 07:57 PM**

Sonnie,
I re-read Wayne's house curve post and I think I get what he was talking about now. I am going to work on gettng it as flat as I can then try his method. Thanks for the point in the right direction. I feel like I'm working against myself, so I am going to start from zero and try again.
Jim

**Sonnie** · **07-26-06, 11:49 PM**

While you are at it you might wanna run a full range response just to see if that area around 150hz is a big hump or is that fairly representative of your main speakers response. Just a thought.

That last graph there looks like your best initial measurement yet. I'd say you are makin' headway.

**azjimmy** · **07-28-06, 10:06 PM**

Ok so I took BruceK's advice and pulled the BFD out of my system and ran my response again.
7_28 no bfd 80 hz x 16hz filter 2 plugs.jpg
This is at 80Hz x-over, 16Hz filter, 2 port plugs. Not too bad, except for a notch at 85 Hz

7_28 no bfd 60 hz x 16hz filter 2 plugs.jpg
60Hz x-over, same port plugs, filter. That notch is still there, but not as deep.

7_28 no bfd 100 hz x 16hz filter 2 plugs.jpg
100Hz x-over...Didn't like the way this sounded.

So far, I like the 60Hz X-over. I like the rise, like a room curve. It's not as localized as it was before. It's still a little lumpy, but a start. Should I bother too much more or sell my BFD?
Jim

**Sonnie** · **07-29-06, 12:09 AM**

Personally if I had that response.... I would not put the BFD in the chain. Sure, you could make it look all pretty and straight, but I just don't believe you'd really notice a difference, if you did you got mighty good ears.

**azjimmy** · **07-29-06, 02:37 AM**

Thanks Sonnie,
I was surprised at my results this time around myself too. The old drivers didn't have a response curve like this. I also didn't have this much headroom in 16 Hz tune either. I'm going to hold on to my BFD for a bit, but for now, I'll leave it off. It's kind of a let down. Now I don't have anything to fiddle with

I guess I'll just have to watch some movies.

**Chrisbee** · **07-29-06, 03:38 AM**

Quote:

azjimmy wrote:

It's kind of a let down. Now I don't have anything to fiddle with

I guess I'll just have to watch some movies.

I'm always being accused of being more interested in playing with the toys than actually listening to them. Given that I listen for several hours every day it isn't exactly true.

But I feel your pain.

Plan B: If you are really desperate you could always boost the sub a bit more relative to the speakers. Then play at pulling the curve back down to a stronger house curve.

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