Passing REW EQ settings onto the DEQ2496?

**Ballistix** · **11-08-07, 06:31 AM**

I take your point. I've found a local supplier for the FBQ2496 which I'm just about to go and pickup...so much cheaper! 100 quid.

Also going to get this to drive it, do you think this cable will be OK? http://www.maplin.co.uk/Search.aspx?...A03FK&DOY=8m11

Cheers

**Rogerio Neiva** · **11-08-07, 05:03 PM**

I am doing everything by hand. It takes doing once, inserting the filters (quite easy), and re-iterate in order to see if now there are no more filters to be inserted meaning that the equalization was successful.

Right now I am starting to work with REW in order just to see how to do it. What buzzes me is what to do with the Waterfall and the remaining data ? How can they be useful ?

**cast55** · **11-10-07, 01:17 PM**

It is definitely worth the effort to plug the REW filter settings into the DEQ manually. One advantage of the DEQ is that it can do all of the filter processing in the digital domain, and output the result digitally to a higher quality DAC. My signal chain stays digital until just before the amplifiers:

digital SOURCE ---->(optical via SPDIF) ----->SRC2496 (upsampling / jitter correction) -----> (optical via SPDIF) -----> DEQ2496 -----> (digital via AES/EBU) -----> DCX2496 (crossover, DAC) -----> stepped attenuators -----> amplifiers

**brucek** · **11-10-07, 02:10 PM**

Quote:

What buzzes me is what to do with the Waterfall and the remaining data ? How can they be useful ?

Well, you can look at a few experiments I did with waterfalls here, and see if it may be helpful.

brucek

**Ballistix** · **11-10-07, 06:54 PM**

Hi guys, I tried it all out today and had a nightmare. Tried the internal card in my Acer laptop (It's 5920G), quite a modern machine.

Got crackes and pops thru the subs, nightmare...then tryied my SB NX USB sound card. No sound...ACK..spent 4 hours trying to get something to work...feedback through the NX was appalling so I couldn't turn the mic up.

Then just at the last minute...I tried the SPIDF out on the Soundblaster NX 2 USB and the MIC in on the internal laptop card!! Testing appeared to work then I had to stop.

Will try again tomorrow...but can anyone see any problems with me doing it this way, using the two cards? I can do the loop back test tomorrow to calibrate the "cards" then see how it goes from there. No feedback and it was a very clean sound..

Was driving me nuts. If someone says this won't work then I'm knackered because I just cant get it to work with one card.

T

**brucek** · **11-10-07, 07:46 PM**

Quote:

Tried the internal card in my Acer laptop

Most laptops only have mic-in and not a line-in that REW prefers, since the SPL meters output line level signals... use an external card with line-in....

Quote:

...feedback through the NX was appalling so I couldn't turn the mic up

This is caused by the cards monitor mode turned on. This is the feature that allows you to record a CD for example and listen at the same time. It needs to be shut off. Look at the soundcards app and deselect it (it can be called by a variety of silly names). You can also go to the Windows XP Playback Mixer and ensure line-in is shut off or muted.....

Quote:

using the two cards?

Just use the external card. Set stereo only, with all effects off and monitor off and it will be fine. Use line-in and line-out.

brucek

**Ballistix** · **11-11-07, 03:23 AM**

Hi Bruce, I've tried eveything through the external card just can't make it turn off the monitoring. Unfortunately I'm on Vista, which sucks when it comes to driver functionality. I've also got a technology background so would usually find the driver stuff quickly. I just can't see where to turn off the monitoring in Vista...I'll search a bit more today.

My laptop does however have line-in so I'm pretty sue it's looking good. The levels look very good when testing. So at the very least I'll try and do a few takes today and put them up here for people to have a look at.

T

**Ballistix** · **11-11-07, 04:56 AM**

OK here is my graph using 2 cards. I simply cannot get this to work with line in and line out on the same card in Vista. About to give up sadly...very annoying as I've just bought the EQ box etc to treat the LFE.

I just get white noise and horrible things trying to use one card. So here is a graph with the input on one card and the output on the other, I can't use line out but I can use SPIDF on my NX USB card. It all calibrated nicely and I've also used the ECM cal file from the site and I've created a calibrated file for the setup for the cards. All tested OK.

However, at the end of my measurement I get an warning that basically says...

However the measurement looks like this. I presume the tail is where the error is?

Any help gratefully accepted although if you think it is to do with the setup I'm pretty knackered on that front it seems.

**brucek** · **11-11-07, 09:02 AM**

Quote:

I can't use line out but I can use SPIDF on my NX USB card.

Not really allowed since that would render the soundcard cal file inaccurate.

Quote:

It all calibrated nicely

No, your soundcard calibration file is bad. It should be basically a straight line except for the very low and very high ends where it should fall off. See what yours looks like - it's the dotted line.

brucek

**Ballistix** · **11-11-07, 04:39 PM**

I'm pretty much knackered then. It doesn't work for me with one card. I've spent near to 6 hours now trying to make it work, and it won't.

Not sure what I can do now. If I use one card I get white noise in the background. The ECM8000 won't pickup enough through the NX USB card, just won't have it. Line out I've sorted now but switching off the monitor but I don't get anything thru the mic once I do.

Dead end. Looks like I'll have to pay for someone to come and do this for me. At least the EQ box can be used as part of their calibration service.

shame, was hoping to do this, unless you have any other suggestions? Anyone else successfully done this with Vista?

Thanks
T

**JohnM** · **11-11-07, 04:54 PM**

What preamp are you using with the ECM8000? It needs a preamp with phantom power.

**Ballistix** · **11-11-07, 05:57 PM**

Hi it's this?

http://www.behringer.com/802/index.cfm?lang=eng

that what you mean?

cheers

TT

**Ballistix** · **11-13-07, 05:27 AM**

John, Bruce, just realised I was using a mono in mini jack for the line in. I'm assuming that won't work or give me spurious results? Off to get another stereo-mini-to-two-phonos connector. Hopefully that will help.

Keep you posted, desperately want this to work.

T

**brucek** · **11-13-07, 07:36 AM**

Quote:

I'm assuming that won't work or give me spurious results?

That's correct. You do indeed require a stereo adapter or cable that splits out the right and left channel, so you can plug the microphone into one of them....

brucek

**Ballistix** · **11-13-07, 10:45 AM**

Hi Bruce, I think I have calibrated the card ok can you confirm? Here is my next attempt...please let me know what you think...what is all the big noise at the end? :S

Feel like a n00b but getting there slowly..

**Ballistix** · **11-13-07, 10:53 AM**

And another cut off at 200Hz OK I'm getting the hang of it!

What you say Bruce? Does the calibrated card graph look better? I'm also using the cal file for the ECM8000.

Cheers in advance!
T

**brucek** · **11-13-07, 11:07 AM**

Yep, the soundcard cal file is fine now.

Always use a vertical scale of 45dB-105dBSPL and a horizontal scale of 15Hz-200Hz for subwoofer or low frequency measurements and 15Hz-(any upper range) for full range measurements.

When plotting full range measurements, turn on smoothing (selectable in the left pane of REW). Smoothing is used for full range measurements, where reflections can cause comb filtering that makes it difficult to see the underlying trend of the response. That's what all the 'big noise' is at the end of the response.

Smoothing is rarely used for low frequency measurements as it would obscure the true shape of the response and so not allow accurate correction filters to be determined.

(some of your pics are missing)

brucek

**Ballistix** · **11-13-07, 11:12 AM**

Hi Bruce, fantastic!

OK what other graphs do you need to see?

Cheers
T

Also getting this error when I try and find peaks.

**Ballistix** · **11-13-07, 11:39 AM**

OK, managed to sort that out! I've been through the rest and got rid of peaks and downloaded the recommended profile to my FBQ2496. Here is the new profile taken using a measurement with the filters on in the FBQ.

What do you think? Any pointers...how do I raise the "dips" so to speak...not very technical with the phraseology I'm afriad! Any help gratefully accepted!

Regards,

Tony

**brucek** · **11-13-07, 11:43 AM**

Display your graphs with a vertical scale of 45dB-105dB and a horizontal scale that starts at 15Hz.

Click the little save icon in the lower left corner of your graph and it will save a jpg of the graph only - we don't need all the other stuff around it.

The response looks fine though..........

brucek

**Ballistix** · **11-13-07, 11:53 AM**

Hi Bruce, OK, how is this?

Anything you think I can do to tweak it? Do the dips matter?

Cheers for all of the help so far!

Also any advice how I can get a HUM out that has been introduced. I can hear a buzz in the sub that wasn't there until the FBQ was introduced into the line. I've put a power cleaning socket on there but it hasn't helped...

Regards,
Tony

**brucek** · **11-13-07, 12:24 PM**

Quote:

Hi Bruce, OK, how is this?

Beauty...

Quote:

Anything you think I can do to tweak it? Do the dips matter?

This is the point where the mains are usually added in and the exact same measure is taken, except now we would look at the relative level balancing of the sub and mains and also the crossover region to see how the mains mix with the sub. Many sub only dips are eliminated at this point by addingthe mains. If a dip or peak is occuring around the crossover, then the subs phase control and the receivers sub distance control are tweaked to get rid of it. Sometimes a bit of filtering is also required.

Quote:

any advice how I can get a HUM out that has been introduced

Yeah, that's a ground loop that these BFD/FBQ's are notorious for creating. To prove it's a ground loop usually you would test with a 'cheater adapter' which basically lifts the safety third prong ground from the FBQ power cord. If the hum goes away, it's a ground loop. Sometimes it's caused by cable TV or some other external ground connected to your system. Some people have to install a transformer based hum eliminator to remove the ground loop.

brucek

**Ballistix** · **11-13-07, 12:39 PM**

Ah OK, I think I see. But for now thats a better profile for the LFE and I could leave that in place until the next step?

I'll remove the centre pin shortly and see if that fixes it!

Thanks again.

Cheers

**Ballistix** · **11-13-07, 01:24 PM**

Bruce, bang on! Removed the earth, no hum. Will leave it for now then come back to doing it properly!

Going to watch the latest Harry Potter tonight with the EQ in place. The Bypass is off and lots of red lights in the right channel so I'm assuming it's in place, it must be because my last screen grab is with it in place.

Thanks for the fab help!
Cheers
T

**Ballistix** · **11-13-07, 04:07 PM**

Bruce, it's made a noticable difference to the listening pleasure. Super stuff. I'll do more reading up with where I go next. I'd like to donate to the site for your help and the super service all round.

Found the donation button and made a donation. Thanks for the super software and great help.

Regards,
Tony

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