Sound System Speaker Calibration?

[Timeless240]

To you professionals, how do you guys calibrate your systems? I have experience calibrating home theater systems, but I was wondering what was different in car audio applications. I have a radio shack analog deciBel meter, but I was wondering how and if you guys ran test tones. Do you guys download high bitrate wavs of test tones and burn them on a cd? My system specs are in my sig, and although I love the sound, I want to get the f-r balance just right as well as a more ideal flat frequency response. I have a few EQ controls in my old pioneer deck, and I want to get the most use out of it without buying a separate EQ.

Yes, I don't have a sub just yet, but I'd still ask the same question down the road when I do get one. Plus, my bostons get down there well, and roll off around the 40Hz range.

[szh]

At home, I use a Radio Shack db meter with 4 different test CD's (3 from Stereophile and 1 from another source.) Here is the link to the Stereophile disk site: https://secure.stereophile.com...shtml. Look near the bottom for the three test CD's. You can probably use these for car audio equipment too!

Personally, I don't worry about the car system - it will always be a less than ideal environment (particularly when compared to home stereo's.) It ain't worth the time or effort for me, IMHO. But, if you are into spending the effort, then the Stereophile CD's may be the right way to go!

Side bar: At home, I also have a Yamaha 10-band stereo equalizer with a calibrated mike that I have been meaning to add to my system one of these days - just not enough hours in the day! It generates white and pink noise sweeps and the mike is used to set the eq levels automatically.

Z

[Simmsled]

Ok, so... you have a nice start here. I see that you are using your amp to power your fronts and your deck for the rears. Good man. I believe that your amp has a variable crossover frequency between 40 and 130hz. I would set your crossover at around 70hz as to not completely buzz your doorpanels off. Your gain for left and right should be the same level and as you turn up your radio from zero volume, you should hear your fronts a bit more than your rears, so adjust your gain accordingly. If you find that changing your crossover on your amp does nothing, then you will have to select high pass on your amp, or turn off the crossover built in to your pioneer cd player. You can find the crossover menu in the sound options on the cd player.

Remember, your Bostons will play louder with less distortion the higher your x-over is, but at the expense of midbass. forget about trying to get your speakers to play down to 40hz in your doors. It is possible, but takes WAY too much dynamat to accomplish successfully, especially with as much power as you are sending to them. You know you are done with gains when you can turn it up to a desireable volume and there is no distortion.

Now... Pioneer has many wacky EQ settings on their units. I usually have found most of them pretty much worthless at volumes higher than 1/4 way up the scale. I would set custom and use these settings:

High +2Mid -2Low -2

Make sure that in your menu on the deck that the FIE (front image enhancement) is off and that SLA (signal level adjustment) is not touched. If you really want to know why, I'll tell you but its basically a bunch of crap.

This should make you happy for now. If I have confused the crap out of you, let me know. If not, ENJOY!!!

[Timeless240]

I appreciate the tips! I have my amp xover highpassed at the minimum of 40Hz, with my deck xover completely off. I have deadened my doors with brown bread and there is no rattling, except for the various tools I carry in my door pockets.

I think I really should have named my thread "compensating for lack of Subwoofer" because I really am looking for that fullness I get from my home theater that I can't yet achieve in my car. My deck eq settings are at Low +5, Mid -2, and High +1, with my boston tweeters set at -2dB in the passive xovers.

Does anybody know where I can find a free download of test tones that I can burn to a CD?

[Timeless240]

found some tones here: http://www.bcae1.com/frequncy.htm

[audtatious]

The interior of a car makes it a bazillion times harder to tune than a home system. So many reflections and boundries that can cause all types of harmonic distortions and staging issues. From a frequency standpoint, you could spend a few bux at a hi-end car audio shop to have them test and tune with a RTA. This will at least give you an idea of where your weak area's are. If you can't adjust out the weak area's, then I would suggest a pre-amp/paraEQ for some additional adjustability.

[szh]

I may be in a minority here, but I think that spending time and money trying to get the ultimate in music perfection in a car environment is not worth it!

Remember that changes in the environment (extra people, windows down, road surface noise, sunroof open, etc.) will change the sound quite a bit anyway.

So, perfecting a single car environment scenario is useless. Just get close enough with a decent test CD, a Radio Shack meter and basic bass/treble controls, and that should be sufficient for most conditions.

My bottom line:

- when you are in your car, drive.

- when you want to listen to good music, go home and sit down in a comfy chair in front of your stereo.

Regards,

Z

[audtatious]

That's good and all, but if you have a "hole" in your frequency response, you have to solve it or it sounds like azz, regardless of the environment.

[szh]

That's good and all, but if you have a "hole" in your frequency response, you have to solve it or it sounds like azz, regardless of the environment.

Certainly agreed!

I only suggest avoiding trying for perfect results - fix whatever is possible within some reasonable time and budget constraints!

Z

[audtatious]

Absolutely

[PoorManQ45]

I kind of with SZ on this one, but I still think that tuning the system in the car is worth as you don't want to torcher yourself while driving.

I would recommend that instead of using a dB meter do do your tuning that you either use your own ear or a female's ear(preferably still attached to her body ). The reason I say that is that it's a proven fact that women have more sensitive ears then men.

Play with the settings while th evolume is turned up to the maximum that you will ever listen to it at, usually 75%. Adjust it to your and her liking, if you can't agree completely, make a compromise with the average of the two values.

I recommend that you turn DOWN the low frequency Eq on your pioneer. You should find the sound alot better at higher volumes.

[audtatious]

Adjusting a audio systems frequency response is actually far from "tuning" a system (IMO). True "tuning" involves hours of speaker positioning for sound stage, tweaking Xover points, etc. "Been there, done that" is my motto. In my "old age" I just want something that sounds pleasant which is far from what I would consider "tuned"....

[PoorManQ45]

Agreed. A properly setup up system usually needs no "tuning". BUT this is an automobile. So the imaging and speaker placement will NEVER be perfect. This can be corrected through things like Time/distance correction, phase correction, an automatic EQ to compensate tfor the peaks and nulls.

One thing I would LOVE to see in a vehicle is an automatic EQ where you could place the Mic whereever you wanted the sweet spot to be and it'd automatically calculate and adjust the signal(S) to put it there. This can and is down in home setups. I guess one could put the same home device in a vehicle, the trunk is a good spot.

[audtatious]

Rockford tried to add some of this functionality with their Symmetry line. Trunk-mounted enclosures with slide-in boards. Not sure if they had a calibration unit, been too long ago.

A lot of people start tuning by finding the resonant frequency of the vehicle before starting their installation. Then they work on the "front end" to work on alignment and staging. Lots of RTA work and listening if you are going for SQ.