# Tuning Your HLCD System



## mattyjman

Now... I'll be the first one to admit I have little experience tuning cars. However, when I didn't have an "autotune" to help me out, I was able to use CMusic's tuning tutorial to get some pretty decent results:
http://www.diymobileaudio.com/forum...rs/33740-simple-way-tune-courtesy-cmusic.html

My question is two parts:

First: I would guess that tuning is a bit different when using a controlled directivity source such as horns, so what do you do different? 

Second: (this builds on the first) especially for competitors please *** how do you tune your HLCD car. What's the process you go through? Is it any different than CMusic's tutorial? Any tips or tricks? (don't worry, i am not competing). 

Thanks for your consideration.


----------



## Mic10is

Copy from Eric Stevens post in another Thread

_High frequencies above 3 Khz are predominantly placed within the sound stage by amplitude and time and phase have very minimal effect.

Midrange frequencies say 500Hz to 3Khz are controlled by time arrival, phase and amplitude. At the higher midrange frequencies the placement becomes more time and amplitude dominated and at the lower midrange frequencies it is more phase and time dominated.

Mid-bass and Low midrange frequencies are dominated by phase and more so as the frequency gets lower. Time and amplitude still have effects but are minimized compared to the higher midrange area._


1st and most important is level setting. something so many people overlook with horns. Horns are extremely efficient and can get really loud. Most people dont pay much attention or at least enough attention to the horn level vs the rest of the system and then wonder why the horns make the system seem extremely bright .

With mini horns, which typically are crossed over at around 1khz. TA will have minimal effect bc its mostly amplitude related.
Sometimes, I''l turn the volume down and turn the Xo down to 800hz or so and play with TA and Phase to see how much the stage and images can shift.

Then the rest is EQ work, paying attention to 1k-4khz where most of the peaks usually are in horns.


----------



## mattyjman

Mic10is said:


> Copy from Eric Stevens post in another Thread
> 
> _High frequencies above 3 Khz are predominantly placed within the sound stage by amplitude and time and phase have very minimal effect.
> 
> Midrange frequencies say 500Hz to 3Khz are controlled by time arrival, phase and amplitude. At the higher midrange frequencies the placement becomes more time and amplitude dominated and at the lower midrange frequencies it is more phase and time dominated.
> 
> Mid-bass and Low midrange frequencies are dominated by phase and more so as the frequency gets lower. Time and amplitude still have effects but are minimized compared to the higher midrange area._


it's funny that you put this in here as this is exactly the thread that i read that made me think that tuning may be a bit different with horns. the concept is the same of course, but the process to get there i would imagine (to get superior results) is tweaked a little


----------



## Eric Stevens

mattyjman said:


> Now... I'll be the first one to admit I have little experience tuning cars. However, when I didn't have an "autotune" to help me out, I was able to use CMusic's tuning tutorial to get some pretty decent results:
> http://www.diymobileaudio.com/forum...rs/33740-simple-way-tune-courtesy-cmusic.html
> 
> My question is two parts:
> 
> First: I would guess that tuning is a bit different when using a controlled directivity source such as horns, so what do you do different?
> 
> Second: (this builds on the first) especially for competitors please *** how do you tune your HLCD car. What's the process you go through? Is it any different than CMusic's tutorial? Any tips or tricks? (don't worry, i am not competing).
> 
> Thanks for your consideration.


I tune all systems the same way. You do need to consider the speakers being used and set crossovers and such accordingly.

The most important part of advanced tuning is becoming a good listener, we can convince ourselves that something sounds good or an image is in the right position when it doesnt or it isnt.

Eric


----------



## DanMan

Eric posted some eq points to get started with as well as some tips for mids. I was skeptical at first, but was astounded at how well it worked.

That's when I realized that Eric was the real deal for sure. I don't doubt anything he says.

The info is at the end of this thread:2000 Honda Accord Lx Sdn - Image Dynamics Forums


----------



## fredswain

I always tuned cars the same way regardless of what type of speakers it had. A very common thing we did was to reverse phase on one of the mids. I would disconnect the tweeters and listen only to the mids. All I would listen for is image location. If it sounded centered then that's the way it stayed regardless of phase. If the phase were reversed on one speaker and the stage wasn't focused or centered, it went the other way. From there tuning began. I never found any differences with tweeter phase and imaging as it just doesn't matter. May as well leave them alone and in phase with each other. 

Reversing phase on a mid may have helped imaging but the sound always drove me insane. I could listen to a car with a mid thrown out of phase and instantly tell it had been done, regardless of how well it was tuned. Sure it imaged better and in sound off competition would score higher but I personally couldn't stand it. Others preferred it. 

The next part is all my personal opinion based on what I learned and found my ear to like. Others may disagree of course. I found that below about 500-600 hz or so that path length between speakers was most important. Aim didn't matter as much. From about 500-600 hz up to about 5K-6K or so, path length and aim are equally important. Above 5K or 6K or so neither aim nor equal path length are important.

Basically the mid bass sounded best when near path lengths were as closed to equal as possible which meant they could most likely stay in phase with each other. This wasn't always possible though and sometimes for best imaging reversing phase on one was the only option. The mid bass area is one place that I really go old school logic on that no one agrees with anymore. What I mean by this is that if I can't get the mid bass set up the way I want them up front in phase with each other to get the desired results, I will then look to other options including putting them behind me such as on the rear deck. This was how the earliest horn installs were done such as Richard Clark's Buick, the original setup in Jim Adam's Firebird, Matt Hashimoto's original setup in his Camaro, and the original setup in Harry Kimura's Acura. Now later on everyone quit doing this for obvious reasons that everything was up front. I have my reasons for still considering this valid though.

In my old RX-7 I had 2 different setups. The earliest was with the horns under the dash and with the mid bass in the rear strut towers. That car was a hatchback and that's where the rear speakers were. These speakers were up higher pointing up. They imaged quite high as a result but as some may point out, behind me. A neat thing happened though when setup really well. Good tuning from the horns still nailed a kick drum up front and everything blended really well with no phase changes needed to get good imaging. When sitting there listening it was not apparent that anything was behind me. However if I turned my head I could tell but even then it didn't sound like part of my frequency range was coming from there. Instead it sounded like low level rear fill. The impression was that the full frequency spectrum was still all up front. It would have scored low in a sound off as a result of having a rear fill sound. The sound quality was very pleasant though and since that is what was most important in a daily driver to me, that's how they stayed for a while. In some ways looking back at that car, that original setup was my favorite for a number of reasons. Simplicity being a big reason. I even had passive crossovers between the mids and horns that had a notch filter we made.

I had tried the mids in the doors but had to reverse phase to get it to image well. This drives my ears crazy and I can't stand it. Having the mids behind me sounded much nicer. I only changed this setup when I finally mounted the mids in the floor in front of the pedals as far forward as they could go. This was the best setup but required cutting holes in the floors. I could also keep them in phase. My personal favorite mid locations with horns are all the way forward in the floor first, the rear deck second, and the doors third. Again, it's an old logic that most would disagree with today but what I personally find most pleasing to my ears. It sounded like a dumb idea until I tried it. Now keep in mind I was using at one time USD horns and then later large body ID horns with crossover points around 800 or so. The higher the crossover point the less desirable the rear mid bass location would have been. My last iteration in that car had mini horns but by then the mid bass were in the floor up front. That setup was best imaging of all of them.

The reason I feel this works is due to path length near equality and not aim. It didn't seem to matter if they were pointed at me or up at a window, or even across the vehicle at each other. It was phase that killed it for my ears and a near equal path length took care of this.

The mid range area above this seemed to like having equal path lengths and proper aim. I am personally not a fan of indirect, reflected energy in this region. I like to spend lots of time with aim after finding the proper location for best path lengths. In the tweeter range up high, their location didn't seem to matter so long as one didn't appear louder than the other. Their aim didn't seem to matter as much either. You could put them in the kicks or in the dash. It didn't seem to matter. Reversing phase didn't either. For me once all of these things were taken care of, tuning would then become very easy.

For tuning using an RTA, I'd stick the mic at head height on the driver's seat in a stand. Only the left channel would play with the right side being disconnected. Using pink noise the response would be smoothed out to near flat with highs falling off steadily and lows increasing steadily. It would slightly lean down to the right. This is just the starting point. Once this was dialed in, the mic would be moved to the passenger side and then only the right side would be played with pink noise. The left side would be off. Again the same slope would be chosen. Once both sides had been tuned, the mic was then moved back to the driver's side but this time both channels would play pink noise. Now the curve would be tweaked evenly to smooth the curve. In other words, if I raised 1K up 2db on the right, it would also go up 2db on the left. Only after these steps had been done would actual listening tests be done. From there with certain reference listening material would any small tweaks be made to the tune. This may take some amount of time. When it sounded good the RTA would be run again with pink noise to see the response curve. Then the last tweaks would be done solely to make sure any response changes from point to point were no more than 3 db but the general curve was maintained. There was no one right curve. Each car is different.

That's how we did it back in the day and when done well worked beautifully. I didn't touch on crossover point settings (if possible) but this technique worked equally as well with horns or conventional speakers.


----------



## jpeezy

Bob troxler?silver rx7


----------



## bigbubba

marked thread


----------



## ariko81

fredswain said:


> I always tuned cars the same way regardless of what type of speakers it had. A very common thing we did was to reverse phase on one of the mids. I would disconnect the tweeters and listen only to the mids. All I would listen for is image location. If it sounded centered then that's the way it stayed regardless of phase. If the phase were reversed on one speaker and the stage wasn't focused or centered, it went the other way. From there tuning began. I never found any differences with tweeter phase and imaging as it just doesn't matter. May as well leave them alone and in phase with each other.
> 
> Reversing phase on a mid may have helped imaging but the sound always drove me insane. I could listen to a car with a mid thrown out of phase and instantly tell it had been done, regardless of how well it was tuned. Sure it imaged better and in sound off competition would score higher but I personally couldn't stand it. Others preferred it.
> 
> The next part is all my personal opinion based on what I learned and found my ear to like. Others may disagree of course. I found that below about 500-600 hz or so that path length between speakers was most important. Aim didn't matter as much. From about 500-600 hz up to about 5K-6K or so, path length and aim are equally important. Above 5K or 6K or so neither aim nor equal path length are important.
> 
> Basically the mid bass sounded best when near path lengths were as closed to equal as possible which meant they could most likely stay in phase with each other. This wasn't always possible though and sometimes for best imaging reversing phase on one was the only option. The mid bass area is one place that I really go old school logic on that no one agrees with anymore. What I mean by this is that if I can't get the mid bass set up the way I want them up front in phase with each other to get the desired results, I will then look to other options including putting them behind me such as on the rear deck. This was how the earliest horn installs were done such as Richard Clark's Buick, the original setup in Jim Adam's Firebird, Matt Hashimoto's original setup in his Camaro, and the original setup in Harry Kimura's Acura. Now later on everyone quit doing this for obvious reasons that everything was up front. I have my reasons for still considering this valid though.
> 
> In my old RX-7 I had 2 different setups. The earliest was with the horns under the dash and with the mid bass in the rear strut towers. That car was a hatchback and that's where the rear speakers were. These speakers were up higher pointing up. They imaged quite high as a result but as some may point out, behind me. A neat thing happened though when setup really well. Good tuning from the horns still nailed a kick drum up front and everything blended really well with no phase changes needed to get good imaging. When sitting there listening it was not apparent that anything was behind me. However if I turned my head I could tell but even then it didn't sound like part of my frequency range was coming from there. Instead it sounded like low level rear fill. The impression was that the full frequency spectrum was still all up front. It would have scored low in a sound off as a result of having a rear fill sound. The sound quality was very pleasant though and since that is what was most important in a daily driver to me, that's how they stayed for a while. In some ways looking back at that car, that original setup was my favorite for a number of reasons. Simplicity being a big reason. I even had passive crossovers between the mids and horns that had a notch filter we made.
> 
> I had tried the mids in the doors but had to reverse phase to get it to image well. This drives my ears crazy and I can't stand it. Having the mids behind me sounded much nicer. I only changed this setup when I finally mounted the mids in the floor in front of the pedals as far forward as they could go. This was the best setup but required cutting holes in the floors. I could also keep them in phase. My personal favorite mid locations with horns are all the way forward in the floor first, the rear deck second, and the doors third. Again, it's an old logic that most would disagree with today but what I personally find most pleasing to my ears. It sounded like a dumb idea until I tried it. Now keep in mind I was using at one time USD horns and then later large body ID horns with crossover points around 800 or so. The higher the crossover point the less desirable the rear mid bass location would have been. My last iteration in that car had mini horns but by then the mid bass were in the floor up front. That setup was best imaging of all of them.
> 
> The reason I feel this works is due to path length near equality and not aim. It didn't seem to matter if they were pointed at me or up at a window, or even across the vehicle at each other. It was phase that killed it for my ears and a near equal path length took care of this.
> 
> The mid range area above this seemed to like having equal path lengths and proper aim. I am personally not a fan of indirect, reflected energy in this region. I like to spend lots of time with aim after finding the proper location for best path lengths. In the tweeter range up high, their location didn't seem to matter so long as one didn't appear louder than the other. Their aim didn't seem to matter as much either. You could put them in the kicks or in the dash. It didn't seem to matter. Reversing phase didn't either. For me once all of these things were taken care of, tuning would then become very easy.
> 
> For tuning using an RTA, I'd stick the mic at head height on the driver's seat in a stand. Only the left channel would play with the right side being disconnected. Using pink noise the response would be smoothed out to near flat with highs falling off steadily and lows increasing steadily. It would slightly lean down to the right. This is just the starting point. Once this was dialed in, the mic would be moved to the passenger side and then only the right side would be played with pink noise. The left side would be off. Again the same slope would be chosen. Once both sides had been tuned, the mic was then moved back to the driver's side but this time both channels would play pink noise. Now the curve would be tweaked evenly to smooth the curve. In other words, if I raised 1K up 2db on the right, it would also go up 2db on the left. Only after these steps had been done would actual listening tests be done. From there with certain reference listening material would any small tweaks be made to the tune. This may take some amount of time. When it sounded good the RTA would be run again with pink noise to see the response curve. Then the last tweaks would be done solely to make sure any response changes from point to point were no more than 3 db but the general curve was maintained. There was no one right curve. Each car is different.
> 
> That's how we did it back in the day and when done well worked beautifully. I didn't touch on crossover point settings (if possible) but this technique worked equally as well with horns or conventional speakers.


WOW. Thanks for taking the time to throw down with that AWESOME post! Just seeing it now...a bit late, but thank you. very helpful


----------

