# Monitoring excessive LFE.1 with spectrumlab



## Andysu (May 8, 2008)

It’s a rather unappreciable channel so I’ll cut to the chase.

What I’ve done is take one film for monitoring (Event Horizon 1997) chapter 8 at (37 minutes 35 seconds to 37 minutes 38 seconds) this where (Sam Neill, Jurassic Park) looks hypnotized as he stares deeply into the rotating ball that powers the ship to travel or bend time and space to reach great distances in a short time.

I’ve re-plugged the connections that used to go as LFE.1 out to my audio mixers line 6 input then from output on one of the two line outputs to the FBQ2496 and then output tracing back though a second EQ that I use to make minor trims if the soundtrack is too much on the LFE.1 which is often the case and often leads to damaged sub bass speakers.

Now I’ve taken the output from LFE.1 sent it directly to the FBQ2496 and from the output to the audio mixers line 6 input and from the output I can monitor the spectrumlab frequency waterfall or waterfalls of independent LCRS if I want though the other low channel outputs from LCRS.

Now what was giving me, the cheeps as much as (the disturbing visual images) from the film LOL was the heavy peak in the middle part of the spectrum. So I looked at it and thought what if I apply a (Q of 1.0) and reduce the level and select a frequency of (43.7Hz -12db for argument sakes) and hmmm, now that’’s different and smoother as well.

I’m going to conduct further testing later on with this approach with the JBL 4645 sub and LCRS. 

I had to borrow the lead that powers the smaller sub bass Eltax A 12-R I need to make up a new XLR lead to go from the FBQ2496, and I have very little solder left.:gah::bigsmile:








Merry Charismas


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## atledreier (Mar 2, 2007)

So we're looking at the actual LFE channel at the source here?
Why would you filter that?


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## Andysu (May 8, 2008)

atledreier said:


> So we're looking at the actual LFE channel at the source here?
> Why would you filter that?


That is good question why would I take this approach that came to me out of the blue and it’s seems to have relaxed the excessiveness of the moment in the film. Anyway its just an experiment at the moment. If I like how it performs I’ll stick to this method or approach that isn’t really doing any harm. I’ll see how far I can stretch this with other soundtracks.

You can see how its softened it out with the two frequency waterfalls.

I made up a new RCA to XLR lead didn’t take long and I’ve used the other XLR female to RCA as monitoring lead. I like how the scene is playing and I’ve had it on A&B repeat for nearly or over an hour talk about obsession with LFE.1. LOL I’m gonna have to find something new or I’ll end like Dr Weir LOL.:bigsmile: It still vibrates the room and sofa.

Merry Charismas


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## atledreier (Mar 2, 2007)

What happens if the peak happens at 30Hz, or 54Hz?

You've just created a 12dB dip at 43Hz, and I can't for the life of me understand why?


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## Andysu (May 8, 2008)

atledreier said:


> What happens if the peak happens at 30Hz, or 54Hz?
> 
> You've just created a 12dB dip at 43Hz, and I can't for the life of me understand why?


Hi there again. LOL I did consider that LOL (trail and error) could be worse LOL.:bigsmile:

Giving another flick a try (Arachnophobia 1990) whoa BASS hevery over the LCR mostly in the centre channel. this film was wicked in THX at the CIC/UCI cinema at High Wycombe on cold early January 1990 but the THX soon warmed me up with in your CHEST BASS as well as the ears getting a heavy beating on the first 15 minutes of the film.:jump:

I do frequency sweep a try with spectrumlab later on with the ECM8000 patched up and take it from there.

Merry Charismas


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## atledreier (Mar 2, 2007)

Could be you have inadverently got rid of a room node and it sounds better, and relieve your straining subwoofer in the process, which is a good thing. 

Merry christmas to you too!


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## Andysu (May 8, 2008)

No strain on it just too loud on the film for this room. Try toast with batter, tuna fish and mayonnaise, yummy.

Merry Charismas to you only 6 days left.


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## Ricci (May 23, 2007)

Andy,

If I remember right you had a very large 30-40hz peak in your sw's room response. You'd be better off using the EQ to get a flatter FR at your listening position before messing with the mix of the soundtrack which will vary everytime. Your sw and listening room will not vary.


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## Andysu (May 8, 2008)

Morning there

Yeah the dreaded peaks wavelengths! You know what tickles me? When I play a sine wave at the lowest 20Hz or 30Hz and open the door too the flat, it just rattles neighbours doors one and two floors down LOL. They probably think it’s the washing machine LOL on full spin! :bigsmile:

I performed a rather length frequency last night longer than usual. I ran REW frequency sound generator (frequency sweep) while looking at the spectrumlab same way as you’d have REW set-up wit the microphone at listening position.

It was the colour spectrum that I was looking at where some frequencies had hot colures of pink and others like green yellow and red. Too bad I don’t have room up front for four subs three at the very least and that would look very ugly staring back at you.

The response is near flat at the moment. Oh, is there a way of saving the frequency bands Q and level settings with the (click on) pdf file mode or does that only capture the frequency response. Also it doesn’t appear to be saving the file each time I go into the file where each one has been saved, it won’t open or at least does, don’t doesn’t display the graph?

I’ll use the (print screen) method at least I know that works.

Merry Christmas only whoa! 5 shopping days left, yikes, looks like I better get my act together for that day.:jump:


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