# Speaker aiming tips by cmusic



## cmusic

This is a tutorial on how to initially aim speakers for two seat listeners. This procedure I use may take only a few hours or could last a few months. I would say it is one of the most critical steps because it determines the sound quality’s foundation of the finished system.

I begin with the midrange speakers since they produce the majority of the frequencies that our hearing is most sensitive too. I leave all other speakers out for this first step. 

The midrange speaker should be placed in the car where it gives 1) the most equal pathlength difference between both left and right sides of the car, and 2) a direct line of sight to the listeners. Minimal pathlength differences have been talked about many times but essentially the less the pathlength difference is the better the audible stereo reproduction will be. The line of sight is not for your eyes, but for your ears. Generally if you can see a speaker, then its sound has a direct line to the listener’s ears. You want to be able to hear the direct sounds from the speaker many milliseconds before the reflected sounds. (There are great sounding systems that mask the direct sound and let the listener hear the reflected sound first. For example, systems with dash speakers. The most successful of these reflected systems aim the speaker directly at the reflective surface so that virtually no direct sound will get to the listener.) Usually you want hear the direct sound at least 60 milliseconds before the reflected sound. In most vehicles this means the best area for the midrange speakers is in the kicks with the seats moved back as far as possible. 

The second step is to bypass all equalization or any other audio adjustments in the system. When possible I like to run a head unit, one two-channel amp (or two matched mono amps), and the left/right midrange speakers only during this step. I use a full range signal void of any crossovers and filters. 

I get two towels and bunch them up in the area the speaker will be mounted. I wire up the two speakers on both sides and sit them in the middle of the towels. I try to mold the towels around the speaker so that they soak up as much of the back wave sound (the sound coming from the back of the speaker) as possible. The lower midrange and midbass will suffer from the speaker’s back wave not being completely blocked, but this setup will be enough to find the best speaker angles. 

It is very helpful to have a listening assistant that is as knowledgeable in sound as it will cut down a lot of time switching seats and re-listening with every minute adjustment. 

I start with the speakers aimed at the center dome light on the ceiling of the vehicle. Both speakers are wired in straight polarity. I listen to a lot of well-recorded music that I am familiar with. Test CDs like from IASCA, MECA, and USACi are very useful too. I listen for tonality, staging, and imaging. I move to the other seat of the vehicle and listen to the same music and test tracks. 

I then reverse the polarity to one speaker and play the same music and test tracks over. Again, I move to the other seat of the vehicle and listen to the same music and test tracks. (There is going to be a lot of switching seats during listening.) If the sound improved then I leave the speakers wired as they are. If they sound worse I reverse the polarity back to straight. 

I then move the speaker in every direction plausible while listening in straight polarity and (one speaker) reverse polarity “rounds” from both seats. Initial changes can be a few inches at a time while fine-tuning changes can be as small as 1/8” or less. The speakers could be aimed up, down, across, directly at the listeners, away from the listeners, different directions, and basically any combination of speaker aiming. There is no set rule that states, “This speaker angle will work in every vehicle”. The best speaker aiming angle is derived from the acoustics of the vehicle and the on and off axis frequency response of the speaker. Since nearly every vehicle (model) is different and there are thousands of different speakers there can’t be one solution for every situation. I’ve had systems with the mids aimed at the ceiling dome light, aimed at the opposite side listener, aimed straight across at each other, aimed directly at the nearest listener, aimed directly up in the bottom of the dash, and other oddball mounting angles. If it sounds great then the actual angle you end up with does not matter (unless you place system looks above sound.) 

There are some general guidelines that I use when adjusting the speaker angles. Soundstage width can be helped by placing the speakers as far to the outsides of the vehicle as possible, but that may hurt image focus. If the center image is skewed to one side, I aim the far side speaker more directly at myself and then aiming the nearside speaker away and towards the other side. Aiming speakers up does not automatically mean the soundstage will rise. 

I then play the tweeters by themselves to find the best angle for them. I would use a high pass crossover to protect them from damage. I would also play them with and without the mids to find the best sound. To mount them up high on the dash or a-pillars or down low with the mids in the kicks or doors is up to the system owner. As many others have suggested, move the tweeters around to find the best sound for your vehicle and system. 

The same steps can be used even if you plan on installing midrange speakers in the doors. I’ve found the best results by using a speaker with excellent off-axis frequency response and aiming them slightly forward towards the center of the firewall. This set the far side speaker with more direct sound, and therefore louder sound than the near side speaker. It helps balance the volume difference between left and right speakers. I then play with the polarity to further tune the system.

The goals are to get as equal of a pathlength difference as possible, a volume level between the left and right speaker as equal as possible, and the frequency response between the speakers as equal as possible. These steps above will help cut the need for signal processing in the system. One can get very close to these goals without using any signal processing. And then by using signal processors carefully one can make an incredible sounding system. 

Hope this has helped. I think I have included everything I know (or can remember  ). You can look up Mr Marv’s post HEREwith my tuning steps for more useful tips. If you have any questions just ask.


----------



## rockondon

Simple ,easy ,clear.

Nicely done.


----------



## Oliver

velcro for the tweeters until you find the right spot ?


----------



## 14642

You can also place a single midrange in the microphone position and place the microphone in the kick panels and measure the frequency response. When you find a position where the pathlengths are similar and the frequency response most closely matches the near field response, you can consider that the best spot. 

This whole aiming thiing is less mysterious than everyone wants it to be. Outside the obvious influence of pathlength (if no time alignment will be used), it's simply a matter of choosing the flattest frequency response and the closest match. Mics and eyes are faster than ears.


----------



## Oliver

Andy Wehmeyer said:


> You can also place a single midrange in the microphone position and place the microphone in the kick panels and measure the frequency response. When you find a position where the pathlengths are similar and the frequency response most closely matches the near field response, you can consider that the best spot.


would reversing the positions not allow for reflections off the underside of the dash ?

It sounds simple enough to do but just doesn't quite seem like it'd be that easy !


----------



## MIAaron

Thanks for taking the time and effort to type this out cmusic. 




Andy Wehmeyer said:


> This whole aiming thiing is less mysterious than everyone wants it to be.


Chuck's tuning tips have helped me greatly in the past and I was very interested in hearing his personal views about aiming as well. I don't consider it mysterious or magical, but I like to hear different peoples views on speaker aiming and tuning. I find the advise I get helps me a lot in real world applications. For example, one of the threads(which is now gone from ECA) was one where Kev7909 was talking about using band limited mono pink noise for aiming as well as for fine tuning with TA. So at the point in cmusic's tuning thread where he talks about playing with polarity to deal with phase issues, I additionally play with pink noise and TA before I go onto freq steering with EQ. I personally find when I use my TA in this manner that I get better tonality in installs that use stock locations.


----------



## thehatedguy

Andy, never thought about doing it like that. Pretty interesting take on the whole thing.


----------



## chad

thehatedguy said:


> Andy, never thought about doing it like that. Pretty interesting take on the whole thing.


Except that most measurement mics are omni... and speakers are not.


----------



## Hoot

I have recently read several things that either conflict with, or perhaps complement, this discussion. I toss them out here so as to generate opinions:

1) When installing kicks, tweeters are best - if possible - mounted either below, or forward of, the mid/midbass;

2) Midrange in a three-way, or midbass in a two-way, should always be on the same plane/axis as the tweeter.

Additionally, with respect to this comment made in cmusic's initial post:

"The most successful of these reflected systems aim the speaker directly at the reflective surface so that virtually no direct sound will get to the listener.) Usually you want hear the direct sound at least 60 milliseconds before the reflected sound. In most vehicles this means the best area for the midrange speakers is in the kicks with the seats moved back as far as possible."

Makes total sense to me, though many widely praised installs have tweets and mids in the a-pillars and I wonder if it is vehicle-specific necessity that dictates choice of tweeter location by the pros, or is it just some voodoo of sound that makes it sometimes work and sometimes not. Cmusic mentions that "true-sound" before "refelected-sound" hitting ones ears is best, and yet higher on/above the dash seems like would automatically invite all kinds of reflections that would wreak havoc on a stage's focus.

Also stated:

"I get two towels and bunch them up in the area the speaker will be mounted. I wire up the two speakers on both sides and sit them in the middle of the towels. I try to mold the towels around the speaker so that they soak up as much of the back wave sound (the sound coming from the back of the speaker) as possible. The lower midrange and midbass will suffer from the speaker’s back wave not being completely blocked, but this setup will be enough to find the best speaker angles."

Wow, fantastic idea. I figured flush-to-the frame, off-axis kicks were generally better because they perhaps allowed for a larger stage. This assumption of mine was based on the idea most great speakers functioned very well off-axis and thus aiming was not a real issue when in kicks, with the most important issue being the above two points listed - don't put your tweet on top or forward of the mid and be sure and have both mid and tweet firing in the same direction. Thoughts?

Great post/thread, here - thanks!

Chad, would love to check out your ride sometime - we're probably about 20-25 minutes from each other.


----------



## chad

Hoot said:


> Chad, would love to check out your ride sometime - we're probably about 20-25 minutes from each other.


That can totally be arranged, I work at the UI


----------



## Oliver

Hoot

This gentleman, [Matt Roberts], was kind enough to share pics of his current IASCA winning install.

read and learn 

http://www.diymobileaudio.com/forum/showthread.php?t=29688


----------



## Oliver

bumpage


----------



## Miffy84

First of all, many thanks to yourself and everyone who's posting these tutorials. It's a great help for a new-comer like myself!

I'd just like to ask, having read about bunching the mids in towels to trial aiming, how do you _keep_ them in position while you listen?

I ask as I have a Ford Galaxy (Euro MPV) and the mids really need to stay in the stock locations at about knee height in the doors and I have no idea how to keep them in position while I sit back and listen.

Any suggestions would be much appreciated!

Thanks again

Smithy 

P.S. Yay for my first post!!!


----------



## jmontoya21

very informative post


----------



## carnut1980

I use some angled MDF baffles to help aim the speakers better. If you have to keep them in the stock location they help.

Elite Installer Supply - Speaker Rings & Templates for Installers


----------



## morty22

i have a very small cab so i went with quart dome mids in my kicks and they sound beautiful with my qm-210's and qm- 19's in my doors!


----------



## veritasz34

Old post but I've got to post..Chucks ideas are grat no doubt and he was a great help to me installing my system..I alway used a laser device and jigs..I placed every drivers center to hit the same spot in the car..Which was usually the dome light..But since my car seats were moved back 8 inches it had to be a little further back..again great advice from a great guy..


----------



## abusiveDAD

thank you sir


----------

