Optimal settings

Idec Sdawkminn · 07-18-2006, 10:52 PM

I was reading you "Rough Tune On EQ" thread and I tried following the advice but ran into some questions. First of all, what should the crossovers be set to? I have my front and rear speakers hooked to the internal amp and my sub hooked to my external one. Fronts are Infinity 4 x 6 Kappas. The rears are Pioneer, but I don't remember the type or size. The sub is a 12" JL Audio. The amp is an MX Audio. I have a Panasonic CQ-C9901U head unit and the slope of the crossovers isn't changeable. They appear to be at 45 degree angles. I have them set for:

LPF: 160
HPF: 90

I set them that way because from 80 to 160 Hz, they are low, so I wanted some overlap. Should they be different?

I turned the gain on the sub all the way down, set all bass/treble settings to 0, and set my SW-Level to 0. I set the volume to be 80 dB at 1 kHz. 80 dB is counted as 0 dB in this chart. I have an '84 Camaro. My current frequency response without EQ'ing is:

With windows up:
20 Hz: -4 dB
25 Hz: -3 dB
31.5 Hz: -1 dB
40 Hz: +3 dB
50 Hz: +8 dB
63 Hz: +7 dB
80 Hz: -7 dB
100 Hz: -8 dB
125 Hz: -13 dB
160 Hz: -6 dB
200 Hz: -9 dB
250 Hz: -7 dB
315 Hz: -3 dB
400 Hz: -9 dB
500 Hz: -3 dB
630 Hz: -6 dB
800 Hz: +3 dB
1 kHz: 0 dB
1.25 kHz: -5 dB
1.6 kHz: -3 dB
2 kHz: -1 dB
2.5 kHz: -1 dB
3.15 kHz: -6 dB
4 kHz: -12 dB
5 kHz: -2 dB
6.3 kHz: -10 dB
8 kHz: -7 dB
10 kHz: -12 dB
12.5 kHz: -12 dB
16 kHz: -22 dB
20 kHz: -24 dB

With windows down:
20 Hz: Too low to not mistake for outside noise
25 Hz: Too low to not mistake for outside noise
31.5 Hz: 0 dB
40 Hz: +9 dB
50 Hz: +11 dB
63 Hz: +8 dB
80 Hz: -4 dB
100 Hz: -9 dB
125 Hz: -15 dB
160 Hz: -3 dB
200 Hz: -20 dB
250 Hz: -3 dB
315 Hz: -1 dB
400 Hz: -8 dB
500 Hz: -5 dB
630 Hz: -7 dB
800 Hz: +2 dB
1 kHz: 0 dB
1.25 kHz: -4 dB
1.6 kHz: -1 dB
2 kHz: -1 dB
2.5 kHz: -4 dB
3.15 kHz: -3 dB
4 kHz: -2 dB
5 kHz: -7 dB
6.3 kHz: -6 dB
8 kHz: -10 dB
10 kHz: -16 dB
12.5 kHz: -12 dB
16 kHz: -22 dB
20 kHz: -24 dB

I have a 9-band paramatric equalizer that covers 20 Hz to 20 kHz. Each band can be changed to equal several frequencies in it's range. The adjustment limits are -12 dB to +12 dB. I'm making a separate preset for windows up and down.

What modifications would you suggest I make according to this data? The biggest priority for me is that it sounds as close to how it did in the recording studio as possible.

Thanks in advance.

JasonWW · 07-19-2006, 09:02 PM

The x-overs depend on the speakers and your preferences. During the tuning process I would turn off the rear speakers and only listen to the fronts. I'd find some music with good midbass kick in it and turn off the sub, set the HPF (your mids cutoff freq.) to about 160hz. Then turn up the volume to a fairly loud level. Is the bass from the mids keeping up and sounding clear? Do you hear any distortion? If everything sounds fine, then lower the freq a little (like 120hz) and listen again. The more bass they play the less volume they will play, so if you like your music loud a higher cutoff point is better. If they can play bass down to 90hz at fairly high volume and they sound fine, then stop there. No point in tempting fate or damaging your speaker.

On to the sub. Set the LPF to about 120hz. At this point only adjust the gain on the sub amp. Turn it up or down to the level it suits you for normal listening. Listen to a variety of songs that have different bass beats or whatever you listen to the most. Adjust the gain to the best compromise. Once the amp gain is set, play around with the cutoff freq. Raising it to 160hz will increase the output some, but also draw the image to the back of the car. You don't want to hear vocals and such comming from the rear so find a freq that makes the music sound most natural. You'll just have to experiment.

Do you know the slopes on your x-overs? Usually they will be about 12dB down per octave. If that's the case you may want to have the low pass set no higher than 120hz or so. Most folks prefer 60-80hz for that low bass sound that keeps the image up front. If you do try a lower freq like 60 or 80 you may need to increase the gain to maintain the overall volume of the bass. Just see what sounds best to you.

About the EQ, a 9 band unit doesn't allow for much flexability. We'll have to look at things as broadly as possible and not so much the 1/3 octave measurements. I would highly recommend one with more adjustability, but I'll try and see what can be done with what you have.

The big swing from 63hz to 80hz is pretty wierd. Are you sure you have the mids playing down to 90 and the sub playing up to 160? It looks more like they are reversed with the sub starting to roll off about 80-90hz plus your midbass seems pretty weak like the mids are not playing very much below 160Hz. Are you sure they are overlapping because it seems like you have a gap there.

On the windows up.
If you have a band at 250hz and 500hz, I would raise them both up by 4-5db. I don't want to suggest anything on your band at around 125 untill we get the x-over settings confirmed.
If you have a 4K band, raise it 4-5 db and see how you like it. If the mids are too high pitched or harsh at loud volumes then tone down that band until it doesn't sound harsh anymore.
Raise the 8k band to 6 or 7db.
Then play with the 16K band to suit you. Start around 6 or 7 db like the previous band and see if you get any hiss. If not, then you might raise it some more. You don't seem to have much output on the top end, where are your tweeters located and aimed?

On the windows down.
I doubt your only 3db down at 160hz. Must be a fluke, it's probably around 10-13 at minimum. I'd stick to the same adjustments as above. The windows being up or down is mostly going to effect the bass and it's usually not that much. I could have a preset for that, but I don't. It's just not worth the trouble.

Edit: What EQ do you have, is the Q adjustable? I first thought you had a regular 9 band EQ, not parametric or quasi parametric. Once I know what you have I'll revise what I said. Keep in mind I don't have a lot of experience with parametrics, so I'll suggest a few things and then you'll need to go back and measure the response around that area to what the effect is. I'm sure we can smooth it out and get it sounding better.

Idec Sdawkminn · 07-20-2006, 01:49 AM

Thank you very much. Out of all the forums I posted this at, this is by far the best response I've gotten. Most of the people tell me what to buy instead. I'm going to buy different things once I have the money saved up, but this is for now. I'll have to get back to you on the crossover settings. I do have a band at 250 Hz, 500 Hz, and at 4 kHz.

Here's how mine works:

Each band can be set from -12dB to +12dB. I believe it is parametric, since the frequencies near the center frequency of each band move with it. The center frequency of each band can be set to:

Band 1: 25, 31.5, 35, 40, 50, 55, 60, 62.5, 65, 70, 75, or 80Hz.
Band 2: 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, or 160Hz.
Band 3: 200, 220, 230, 240, 250, 270, 280, 290, 300, or 315Hz.
Band 4: 400, 425, 450, 475, 500, 525, 550, 575, 600, or 630Hz.
Band 5: 800, 850, 900, 950Hz, 1.00, 1.05, 1.10, 1.15, 1.20, or 1.25kHz.
Band 6: 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, or 2.5kHz.
Band 7: 3.15, 3.25, 3.50, 3.75, 4.00, 4.25, 4.50, 4.75, or 5.00kHz.
Band 8: 6.3, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, or 10.0kHz.
Band 9: 12.5, 13.0, 14.0, 15.0, 16.0, 17.0, 18.0, 19.0, or 20.0kHz.

The width of the Q is not adjustable. I don't know the slopes but they appear to be 45 degree angles. I do know that the LPF can be set to from 60 to 160Hz with 5Hz increments and the HPF can be set from 90 to 225Hz with 5Hz increments.

JasonWW · 07-20-2006, 12:20 PM

OK, you have a quasi parametric instead of a true parametric. The width of frequencies effected on both the left and right of the center frequency is known as the Q. A wide Q would effect a lot of frequencies near it and a narrow Q would only focus on the few right at the center frequency. Yours must a have a fixed Q. A 45* angle means nothing. There should be some info on your model about what the Q is. Maybe there is an online manual for it.

Did you check the x-over freqs? Does your system sound weak in the midbass area?
Also, what source material are you using to measure those earlier responses?
If you don't think your x-overs need any tweaking, then try this.

Band 1 to 50hz and cut it 3 dB.
Band 2 to 125 and raise it 4 dB.
Band 3 to 250 and raise it 3 dB.
Band 4 to 500hz and raise it 4 dB.
Band 5 leave it flat.
Band 6 leave it flat.
Band 7 to 3.5kHz and raise it 3 - 4 dB.
Band 8 to 8kHz and raise it maybe 4 - 5 dB
Band 9 to 14kHz and raise it around 7 - 8 dB

Bands 8 and 9 are mainly the tweeter so depending on where they are mounted and aimed you may need to add more or less. Sometimes the SPL meters don't pick them up too well if your tweets are very directional. So just play with the levels on bands 8 and 9 so that you can hear the highs,but you don't want them to sound tinny or harsh or too overbearing. You don't really need good reponse out to 20kHz, 16kHz is more realistic for actual listening so if the response rolls off on the very top it's no big deal. We can move the center freq of band 7 closer to 5kHz if you think the sound should have more bite or sharpness to it, otherwise the 3.5kHz center freq should sound a bit more mellow.

Crank up the volume and see how it sounds. Do you have any high end recordings from Telarc, Sheffield or anything known to be accurate and have good tonal response without being compressed? That's what you need to listen to to check the tonal balance. Voices in particular need to sound realistic like they are from a real person standing nearby.

What kind of music are you going to be listening to most of the time?

If it sounds better, then plot out the response again using your SPL meter and we'll see what the adjustments did. We'll look to see if the dips and the peaks are better or still there.

Idec Sdawkminn · 07-20-2006, 11:03 PM

I said I'd get back to you on the crossover settings because I had to go to bed and couldn't be messing with them. I'll mess with them when I have more time and post back once I have.

Besides that, I forgot to mention that the front speakers are in the top of the dash and pointing straight up. I had them installed in 2002 by an audio retailer.

What kind of music am I going to be listening to mostly? Well, the bands I listen to the most are Ayreon, Nightwish, "Weird Al" Yankovic, Air, Video Game Music, Stratovarius, Dream Theater, Therion, Symphony X, Jamiroquai, Sonata Arctica, X Japan, The Black Mages, Daft Punk, The Mars Volta, etc.

After I mess with the crossover like you said, I'll try those adjustments.

Idec Sdawkminn · 07-22-2006, 02:44 AM

Well, I put on some Daft Punk and made sure to get somes with lots of bass and then did what you said with only the front speakers and I got good volume with no distortion (that I could tell) all the way down to 90Hz, so I have both LPF and HPF at 90Hz right now. I'm getting an amp for the fronts in the mail. It's an Aura.