I opened up a can of worms recently when I decided to calibrate my system using the Video Essentials DVD and an SPL meter. I also researched other posts on this forum regarding db and EQ settings but there weren't any "Ahhh Hahhh" answers to be found. So now I'm posing the question of these db and EQ settings to you all, in search of that "Ahhh Hahhh" answer. Is there a STANDARD setting for Bass,Midrange and Trebel frequency settings? Were all of these settings made available only to be left alone? I don't want to believe that. I know that every HT setup, respective EQ settings and personal preferences will vary, but what do we use as "Reference" settings?

There is no real standard to these setting but for me, I define them as:

Subbass 20-100Hz
Midbass 100-500Hz
Midrange 500-3000Hz
Treble 3000=8000Hz
Super Treble 8000-20000Hz

That's a rough guide.

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Regards...
#Other TEAM 7 Member
Drinker of much Pepsi, trainer of Dingo's and Jack's Aussie Moonshine importer...
John 3:16

quote:<HR>Originally posted by DTS-Man:
Is there a STANDARD setting for Bass,Midrange and Trebel frequency settings? Were all of these settings made available only to be left alone? I don't want to believe that.<HR>

I'm no expert, but from everything I have read or heard, the 'reference' EQ should be perfectly flat. In other words, don't boost the bass or treble at all, because you're only coloring the original recording. Most people who say this also have very nice equipment that they believe does not need to be fine-tuned with an EQ.
If you've got a parametric EQ and a test disc, you might want to experiment with the sound, but if you've just got bass and treble knobs, I think you shouldn't worry about this.

Just to echo Digit's explanation.

Equalization can be used to produce a reference level speaker response.
Variations in room response, placement, and equipment add unwanted dips and peaks to a systems frequency response, changing what a recording was intended to sound like.
You should produce a flat frequency response w/the standard test signal: the same SPL level played from roughly 20 Hz to 20 kHz.
One way to do this is by using a equalizer to take out the unwanted dips and peaks.


To properly equalize, you need a multiband equalizer (more than treble, midrange, bass) and a real time analyzer and a good microphone. The amount you adjust by is highly system dependent. There are no standard values anyone can tell you.

A crude step in this direction is a 3 band equalizer like the one on some Sony receivers. The bass (treble) band is a shelf type equalizer - ie, all frequencies below
(above) the frequency are cut or boosted by the same amount - basically advanced tone controls. The midrange band (at least for the 777ES) is a parametric EQ, where you can adjust the width of the filter as well as the height and center frequency. This can be used to address ONE peak or dip in the midrange. (Unfortunately, this equalizer doesn't do down low enough to address the most common HT eq problem: a big room-induced bass peak)

If you really want to pursue this, two ideas come to mind. There are test tone CD's available that play various frequencies, swept and stepped. W/a SPL, you can measure how far from ideal your system's frequency response is. You'll make a table of fequencies which ideally should be all the same and then make a best guess where your equalizers will do the most good. There are also downloadable shareware real time analyzer programs. You plug your SPL meter into your sound card. The program shows you a spectrum. You adjust your EQ's to make the frequency flatter. Again, this is a fair amout of work for only 3 bands.

Finally, EQ's can also be (mis)used to arbitrarily distort recordings by adding excessive boominess or crispness. It's pretty easy to fall into this if you're just doing things by ear.


[This message has been edited by BEC (edited February 05, 2001).]

Ahhhhh Hah! You've all made some good sense regarding the EQ, Thanks! So with that info. in mind let me ask you this: With the EQ settings flat, describe to me how you have performed the 75db calibration procedure to your systems using the available Video/Audio DVDs. I used the Video Essentials disc, which is very brief on the audio setup and may lack some detail. Do you start with your volume settings at your usual listening levels, all dB settings at ZERO and "tweak down" or do you start with volume low, dB at ZERO and "tweak up"? Do you start with your LFE dB settings at ZERO and tweak the sub or vice versa? I can't keep from pegging the meter no matter what I do to my sub or LFE settings. Is that typical?

It appears that BEC is more qualified to answer this, but you'd want to set all the EQ bands to 0 and get an audio test disc that sweeps through the frequencies. Video essentials does not offer this. Then, adjust +/– for each band to tame the weak/strong frequencies. I would imagine that you'll experience more noticeable problems in the lower frequencies.
And as far as misuing an EQ, I admit that the only use I'd have for one is to minimize hiss and midrange in tapes and LPs.