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Discussion Starter #1
I've read about extensively how much SQ in stereo build is based on install and tuning. After heavy reading and experimentation, i am still at a loss on how to get the tuning adjustments right. My stereo sounds good, but i know it could be better. My attempts at fine tuning have fallen short because basically I am trying things without knowing what im doing or why. Thus im reaching out to the community to ask for solid example using my system for initial specific settings you would begin with. While I realize that it is hypothetical since you are not hearing the system, I still want to see the numbers so i can see how they vary from speaker to speaker and further my understanding of the big picture.

What would really be helpful is to list what each speaker should be set at (ACTIVE SETUP) including gain level, crossover frequency / type, slope, as well as a time alignment number. Any other settings for each speaker would be helpful if I missed anything. As you can see, I am seeking more than general information such as crossover the mid at 80Hz.

My gear is a two way active setup of Focal K2P separates with a pair of 8" subs in the back on a 6 channel Zapco DC 650.6 AMP installed in a Tundra Crewcab. Tweeters are in the sail panel and midrange in door down low by feet(factory locations). Woofers are under rear seat. My amp is Zapco DC 650.6 so I can make fine tune adjustments with a laptop including Time Alignment.

Can someone list what they would set each XO frequency / type, gains, and slope for each speaker and the time alignment so I can understand what the variances would be for fine tuning. Hopefully this will be helpful for others as well to learning how to really tweek a system.

Speaker 1 Front LEFT Tweeter
Speaker 2 Front RIGHT Tweeter
Speaker 3 Front LEFT Midrange
Speaker 4 Front Right Midrange
Speaker 5 & 6 Dual VC Woofers bridged on the amp.

Thanks so much to anyone who will respond.
 

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Can you post a link to the manual so one can see what sort of dsp is on hand? The link from the Zapco site doesn't work.

Try crossing the sub and mids ~60ish and use the steepest slopes you have. Then cross the mids and tweets ~3-4khz, again on steep slopes. Leave it this way for now.

Time alignments allows you to hear speakers that are at different distances, at the same time like you would in a normal 2ch home setup. So you want 0 delay on the speaker furthest from you and max delay on the one nearest you. This delay is set either in milliseconds or in measured distance. I'm not sure how its done on the Zapco. If its in measured distance (cm/inches) then for a start measure the distance of each driver from your listening position and enter those distances.

If you have to do it in ms, then cut all drivers except the sub and the far mid. Set the sub to 0 and start adding delay to the far mid. You want to get to a point where you hear the sub frequencies as if they were coming from the far mid. Now cut the sub and play both the mids. Add delay to the near mid to the point where you hear the bulk of the sound coming from the front. You'll still hear some sound drifting towards the speakers cause its not balanced for L/R but the bulk will have a frontal presentation.

To dial in the tweets, play only the mids and tweets on one side and add delay to the tweet till you hear drivers as a point source, the bulk of the sound should be at the level of your tweeter. Do the same on the other side and now play all the drivers.

This is a very rough guide to setting the TA. With all drivers playing, you will have to tweak a bit to get things to shape up. Does the Zapco do eq too?
 
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If you have to do it in milliseconds, then use your tape measure and the formula for the speed of sound in air--1132ft/second to determine the values in mS.
 

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If you have to do it in milliseconds, then use your tape measure and the formula for the speed of sound in air--1132ft/second to determine the values in mS.
I would not know how to do this calculation and apply it to my car.

That is why im asking for the values of each speaker even in hypothetical so I can see what each number would be relative to the other speakers.

Thanks,
 

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Discussion Starter #5
Can you post a link to the manual so one can see what sort of dsp is on hand? The link from the Zapco site doesn't work.

Try crossing the sub and mids ~60ish and use the steepest slopes you have. Then cross the mids and tweets ~3-4khz, again on steep slopes. Leave it this way for now.

Time alignments allows you to hear speakers that are at different distances, at the same time like you would in a normal 2ch home setup. So you want 0 delay on the speaker furthest from you and max delay on the one nearest you. This delay is set either in milliseconds or in measured distance. I'm not sure how its done on the Zapco. If its in measured distance (cm/inches) then for a start measure the distance of each driver from your listening position and enter those distances.

If you have to do it in ms, then cut all drivers except the sub and the far mid. Set the sub to 0 and start adding delay to the far mid. You want to get to a point where you hear the sub frequencies as if they were coming from the far mid. Now cut the sub and play both the mids. Add delay to the near mid to the point where you hear the bulk of the sound coming from the front. You'll still hear some sound drifting towards the speakers cause its not balanced for L/R but the bulk will have a frontal presentation.

To dial in the tweets, play only the mids and tweets on one side and add delay to the tweet till you hear drivers as a point source, the bulk of the sound should be at the level of your tweeter. Do the same on the other side and now play all the drivers.

This is a very rough guide to setting the TA. With all drivers playing, you will have to tweak a bit to get things to shape up. Does the Zapco do eq too?
LINK TO MANUAL IS HERE
Zapco - DC Reference

From this page click the link for DC1000.4 it will bring up the manual for a similar amp to the DC650.6. Unfortunately the link my particular amp is not operational.
 

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Because of reflections, there in three dimensional space , are being created zones with different acoustical pressure. Sound from every speaker travels by its own unique path thought zones with minimal acoustical resistance. And this path is radically changing in dependence from frequency. Picture is complicated by speaker’s beaming. “Petals” of beaming are mowing with frequency too. Even with TA you can’t set the phase for all frequencies. The tape measure can be a good start, but most accurate settings could be done by adjustment of weighted phase of full spectrum. Your ears and focused white noise will be most precise instrument to do it.
 

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Discussion Starter #7
Because of reflections, there in three dimensional space , are being created zones with different acoustical pressure. Sound from every speaker travels by its own unique path thought zones with minimal acoustical resistance. And this path is radically changing in dependence from frequency. Picture is complicated by speaker’s beaming. “Petals” of beaming are mowing with frequency too. Even with TA you can’t set the phase for all frequencies. The tape measure can be a good start, but most accurate settings could be done by adjustment of weighted phase of full spectrum. Your ears and focused white noise will be most precise instrument to do it.
Thanks for the response. I do agree that ears are probably the best way of determining that everything sounds great. The problem I am having is that I do not know what adjustments need to be made and thus I adjust things without knowing what is behind it. Sometimes I get lucky, but this is just guessing and mostly im just moving in a random way. It doesnt help that my ears are not the best at tuning, but I do know good sound when I hear it.

I am a visual person and learn by seeing and hands on. Problem is that there is nobody to show me or for me to learn from. If I had some mentor sound guru present who said, "look this is what I am doing and why" "When I adjust this, look at what it is doing visually on this meter and how it sounds". I do not have that person at my disposal so I learn from reading, but that is so difficult and less than ideal.

If someone can say this setup is similar to how your system's settings might look like, at least I could get a big picture of "OK the gain on right side speaker is higher than driver side, or passenger side speakers are on a steeper slope than driver side. That way, even though generalized and not actual settings, i can venture to start tweeking with something rather than just total guesswork.

Since i know that many folks have 2 way active setup with subs, and probably in similar car to mine (SUV or Large Pickup Truck), maybe they can just list their settings for Speaker / Amp settings. Hopefully if your system is fine tuned and sounds awesome, I can try to mimic it as a baseline to adjust from.

Thanks,
 

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You can start from basic settings.
Subwoofer LP 80Hz 3rd order(18db/oct)
Twitter HP 3800 3rd order(18db/oct).

High pass for midwoofer is most various for different installs.
Start it from HP 70Hz 3rd order(18db/oct).

I don’t like highs and a lover LP limit for midwoofer allows having the twitter
a bit attenuated. At the same time the high order makes the sound too “sterilized” or dry.
Thus, LP 3500 2nd order(12db).

Initial delay setting for every speaker will guarantee that finally you don’t have the phase between them shifted on big number of periods.
There is thread, something like “Settings the time alignment via ears and white noise”
You don’t need in golden ears to hear difference between focused and unfocused noise.
After that, you can check what going on with frequency response by RTA.
The fine tuning can be achieved after long time of critical listening, there always will be musical compositions where you can note that there is something wrong. Hardest part is to decide why it happens.
 

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Wow, now I am beginning to understand how some folks can spend weeks dialing in their stereo systems. Short of spending alot of time to initially learn, there seems to be no other way.

I need a stereo Yoda to teach this Padawan to become Jedi.
 

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Numbers will get you to a point, but your ears have to tell you if it's 'the' point or one close by. You mentioned you're a visually oriented person. Most people are. You don't have to change your orientation, just sharpen up another sense.

There's a reason I gave you that seemingly random way to set your TA. I wanted you to get started with 'hearing the difference'. Tuning is not about getting it right the first time. You rarely will. There are three things you should have. A good reference / baleline sound you're aiming for, train your ears to hear 'the difference' and evaluate 'better or worse', with some degree of accuracy and an almost instinctive feel for the dsp at hand. What does the ideal delay between sub and mids sound like? What happens when you increase / decrease the delay on the sub beyond this point. What does each frequency do to the sound? If 1.25khz is too hot what will it sound like? etc etc.

If you can focus on these three areas, your sound will improve over time. But since its hit and miss till you get comfortable with things (even then its hit and miss but the frequency of hits is better). Hence it's going to take some time and you'll need to be patient with this.
 
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