Nismo audio upgrade- critique my planned setup

bigaudiofanat · 04-16-2010, 03:18 PM

Still I have to say I would take focal over pioneer and polk any day after hearing the polyglass ones. Although the polk SR's are very nice.

speedfreak28 · 04-19-2010, 10:48 AM

Lol, dunno why your so bent out of shape because I said there were a ton of cheaper, better options than your focals. Just because you bought an overpriced set of components doesn't make your car an award winning sq install. I'd love to see the how you have the speakers imaged and how the wires are ran and terminated. SQ is a lot more install then product used.

2fast4thelaw · 04-19-2010, 11:53 AM

There are many photos and unique designs in my audio system on this site that speak for themselves. Everything in my car has been designed and engineered specifically for my car. I have even shared my subwoofer enclosure design with some of you that took countless hours of design and engineering.

I had to have a shop do the fabrication and installation because fo one, I dont have a Machine shop and a wood shop at my disposal anymore, next I didnt have the time to strip my car down to deaden it.

I have done both active and passive cossovers on my fronts and I actually gained better results from the passives but my passives have been modified and redesigned by me to taylor them for the interior of my car and the thier location. So dont go there buddy! You are outta your league.

37Z · 12-22-2010, 08:15 PM

[QUOTE=2fast4thelaw;503671]There are many photos and unique designs in my audio system on this site that speak for themselves. Everything in my car has been designed and engineered specifically for my car. I have even shared my subwoofer enclosure design with some of you that took countless hours of design and engineering.

Have you designed a sub enclosure in the 370Z hatch area located in front of the rear cross bar area (i.e. where the foam piece is located)? It may allow a 8" sub if the top of the sub enclosure is angled. I plan to install the amp (JL Audio HD 600/4 or 900/5 for its size) in this location as well. I plan on making the sub enclosure out of composite RFP (i.e.lightweight,dense,able to form curves). Any sub enclosure design thoughts would be appreciated! I can PM back with pics.

bigaudiofanat · 04-19-2010, 01:05 PM

LOL speakers tailored for your car, doubt it. How they are aimed and setup that is something that I would believe. Speed knows what he is talking about and someone I talk to a for advice. So chill out!

2fast4thelaw · 04-23-2010, 10:10 AM

Quote:

Originally Posted by bigaudiofanat

LOL speakers tailored for your car, doubt it. How they are aimed and setup that is something that I would believe. Speed knows what he is talking about and someone I talk to a for advice. So chill out!

You doubt becasue you and 95% of enthusiasts out there dont understand how crossovers really work. They do much more than filter frequencies. You can alter the phase and shift the time alignments on the drivers to compensate for tweeter location and for the material it reflects off of like glass vs plastic, leather, or even carpet. Crossover design is a science that is used in DIY world of car and home audio. Some people think its a bandaid solution and it is if you use inferior quality speakers ie "BOSE" but it does work!

I have been doing DIY for 15 years and I have developed my own custom software for crossover and enclosure design. If anyone is interested in it I might even share it.

speedfreak28 · 04-24-2010, 12:39 AM

Quote:

Originally Posted by 2fast4thelaw

You doubt becasue you and 95% of enthusiasts out there dont understand how crossovers really work. They do much more than filter frequencies. You can alter the phase and shift the time alignments on the drivers to compensate for tweeter location and for the material it reflects off of like glass vs plastic, leather, or even carpet. Crossover design is a science that is used in DIY world of car and home audio. Some people think its a bandaid solution and it is if you use inferior quality speakers ie "BOSE" but it does work!

I have been doing DIY for 15 years and I have developed my own custom software for crossover and enclosure design. If anyone is interested in it I might even share it.

Im curious how your changing the phase in your passive crossovers. The phase you can control through the crossover is electrical by utilizing different crossover slopes. You said you were using the focal passives so Im lost there.
Also phase as you refer to it being affected by the vehicles acoustics is not controlled through the crossover but rather through the install, aiming, and level matching primarily. Im also curious how you're utilizing time alignment with a passive network. You would only be able to adjust the stage left and right. Time and Frequency of a driver are two different functions, correct me if Im wrong. Also if you are using a passive filter time alignment wont help with height of your tweeter and the only way you can change phase without moving the tweet is to adjust the slope, affecting the electrical phase.

Again please dont take my comments the wrong way. I hope Im not out of my league because I'd like to think we can have an intelligent discussion. Id be curious about the program you made for crossover design. It could be a nice tool to add to my collection.

2fast4thelaw · 04-25-2010, 12:22 PM

Quote:

Originally Posted by speedfreak28

Im curious how your changing the phase in your passive crossovers. The phase you can control through the crossover is electrical by utilizing different crossover slopes. You said you were using the focal passives so Im lost there.
Also phase as you refer to it being affected by the vehicles acoustics is not controlled through the crossover but rather through the install, aiming, and level matching primarily. Im also curious how you're utilizing time alignment with a passive network. You would only be able to adjust the stage left and right. Time and Frequency of a driver are two different functions, correct me if Im wrong. Also if you are using a passive filter time alignment wont help with height of your tweeter and the only way you can change phase without moving the tweet is to adjust the slope, affecting the electrical phase.

Again please dont take my comments the wrong way. I hope Im not out of my league because I'd like to think we can have an intelligent discussion. Id be curious about the program you made for crossover design. It could be a nice tool to add to my collection.

I apologize if I came off a bit negative, anyway this forum is about sharing information and this is a bit lengthy so here goes.

The problem with stock passives is they are designed primarily for having the mid and tweet close to each other and on the same baffle or panel. This largely why they get a bad rap especially if you are forced to put components in unconventioal places. Basically a car is an unconventional envornment for audio. In order to resolve these problems we have to re-design our passive crossover network and taylor it for our envoirnment.

Phase and crossover slope are 2 separate entities and in this case slope remains unchanged.

Now adjusting the phase is a whole other science. Car speakers are optimized to perform well off-axis (speakers that play indirectly) vs home speakers that are optimized for on-axis (pointing directly at you). No matter how good off-axis speakers are, they will still sound better on-axis.

What I try to do is put the tweeter on axis by adjusting the phase anywhere between 90 and 270 degrees. In doing so this will change the time alignment between the mid woofer and the tweeter. You can calculate your resistor values that you will need to correct the change in time alignment. Let’s say you have a lot of carpet in your car, then you want your time alignment to be quite advanced because of the non-reflective materials in the car. If you are reflecting off of glass then you need to go the other direction because of the reflective material.

Applying this to the Z:

I chose to use the stock location for my mid’s and tweets. What I did was roll my tweets 270 degrees off-axis by changing the values in the resistors on the passive crossover. (I will explain why I did this later) Since they are reflecting off of glass I used the lower settings on the crossover volume to cut a little output from them to compensate for the db gain from the reflection from the windshield.

In the Z, the distance between the tweets and mid’s are about 18 inches but again the fact that they reflect from the windshield made the phase invert. I not only had to flip the phase 180 degrees to put them back into phase, but I added an additional 90 degrees to make the illusion that they were in front of my face. This was a total of 270 degrees of phase adjustment.
In order to get my values I had to reverse engineer the Focal passive crossovers.

These crossovers are 3rd order Butterworth 18/db octave crossovers so they were not that complicated. I just punched in the component values in my software and then my software program spits back the values after I have it calculate the phase I want.

I just had to order some 1% tolerance resistors and capacitors of equal quality and replaced the components.

This still changed some behavior of the tweeter and mid woofer relationship but remember I have a 13 band parametric eq which fixed this problem and I was able to blend them perfectly, at least to my ears.

My imaging is dead on and dramatically better than it was just rolling with the stock passives.

speedfreak28 · 04-25-2010, 04:08 PM

Quote:

Originally Posted by 2fast4thelaw

I apologize if I came off a bit negative, anyway this forum is about sharing information and this is a bit lengthy so here goes.

The problem with stock passives is they are designed primarily for having the mid and tweet close to each other and on the same baffle or panel. This largely why they get a bad rap especially if you are forced to put components in unconventioal places. Basically a car is an unconventional envornment for audio. In order to resolve these problems we have to re-design our passive crossover network and taylor it for our envoirnment.

Phase and crossover slope are 2 separate entities and in this case slope remains unchanged.
slope directly affects phase, for every 6db/oct adjustmnet phase changes 90 degrees
Now adjusting the phase is a whole other science. Car speakers are optimized to perform well off-axis (speakers that play indirectly) vs home speakers that are optimized for on-axis (pointing directly at you). No matter how good off-axis speakers are, they will still sound better on-axis.

What I try to do is put the tweeter on axis by adjusting the phase anywhere between 90 and 270 degrees. In doing so this will change the time alignment between the mid woofer and the tweeter. You can calculate your resistor values that you will need to correct the change in time alignment. Let’s say you have a lot of carpet in your car, then you want your time alignment to be quite advanced because of the non-reflective materials in the car. If you are reflecting off of glass then you need to go the other direction because of the reflective material.
using a 18db/oct filter will change the phase of the drivers 270 degrees this is normally fixed by making sure the woofer and tweet are hooked up with opposite phase. that doesnt put the tweet on axis. A tweeter would faced up at the windshield would most likely need a -6db/oct attenuation to sound closer to on axis. Time alignment is a measure of the distance the speaker is from the reference point( your head in the drivers seat) not a measure of the distance between the tweeter and woofer
Applying this to the Z:

I chose to use the stock location for my mid’s and tweets. What I did was roll my tweets 270 degrees off-axis by changing the values in the resistors on the passive crossover. (I will explain why I did this later) Since they are reflecting off of glass I used the lower settings on the crossover volume to cut a little output from them to compensate for the db gain from the reflection from the windshield.

In the Z, the distance between the tweets and mid’s are about 18 inches but again the fact that they reflect from the windshield made the phase invert. I not only had to flip the phase 180 degrees to put them back into phase, but I added an additional 90 degrees to make the illusion that they were in front of my face. This was a total of 270 degrees of phase adjustment.
In order to get my values I had to reverse engineer the Focal passive crossovers.

These crossovers are 3rd order Butterworth 18/db octave crossovers so they were not that complicated. I just punched in the component values in my software and then my software program spits back the values after I have it calculate the phase I want.

I just had to order some 1% tolerance resistors and capacitors of equal quality and replaced the components.
what you did above is create a Zobel network that is normally used to counteract the difference in inductance between drivers( basic level matching) normally the woofers in the door are about 60 degrees of axis, Im assuming you compensated for that as well.
This still changed some behavior of the tweeter and mid woofer relationship but remember I have a 13 band parametric eq which fixed this problem and I was able to blend them perfectly, at least to my ears.

My imaging is dead on and dramatically better than it was just rolling with the stock passives.

The problem with using the 13 band EQ through a passive filter ( Im assuming an eqx or something similar is that you are not adjusting the characteristics of the individual speaker but the whole passive network. this makes it really difficult to accurately tame peaks in an individual speaker because you will change the characteristics of the other as well. Heck, phase can change with frequency as it comes off a speaker. Also what may sound flat to you and imaged dead on may not be the same on an RTA. Realistically unless its a competition vehicle whatever sounds good to you should be your ultimate goal. SQ is subjective, measured SQ is not

jikhead · 04-19-2010, 01:51 PM

Is this an East Coast vs. West Coast thing? Haha!

sobewebmaster · 04-23-2010, 01:05 PM

I'd like to throw in a suggestion for the component speakers, Infinity Kappa Perfects. Should be about the same price range as the Type-X.

Your best bet would be to hear them in person somewhere, like an audio shop. I love Alpine products, I have a complete Type-R setup (including vPower M500 mono amp & F300 4chan. amp, 12" Type-R sub, etc. etc.) and I absolutely love it. But I would really say, after hearing the Infinity Kappa Perfects powered from an Infinity 500w multichannel amp in a friend's GTO, I was just shocked at the clarity at high volumes, not to mention the bass they provided as well.

fuct · 04-27-2010, 03:07 PM

so that NISMO audio upgrade.... hows that thing coming?

speedfreak28 · 04-27-2010, 06:44 PM

pm sent. yea thats the problem with alot of programs is that a home audio environment is way different and makes it tons easier to use a passive network.

speedfreak28 · 05-11-2010, 07:43 PM

I agree with 2 fast, 12w6v2 and the 900/5 is a great start, that is 500rms and the amps use regulated power supplies and put out that power from 2 ohm to 4 ohm

rockhounds · 05-17-2010, 02:46 PM

Hey guys, quick question... I'll be installing the audio system by myself and I was wondering how can I install the tweeters. As I said, the Focals 6.5" support 75WRMS + the tweeters. I 'm thinking about bridging the 4 channels of my JL HD 900/5 into 2 channels but I don't know how to configure the crossover in order to avoid problems blowing up the 6.5" if I hook them up in series with the tweeters. Any suggestion?

Thanks!

04-16-2010, 03:18 PM	#1 (permalink)
bigaudiofanat Car Audio Installer Join Date: Jun 2009 Location: Magnolia DE Posts: 8,342 Drives: 2012 Infiniti G37x Rep Power: 854	Still I have to say I would take focal over pioneer and polk any day after hearing the polyglass ones. Although the polk SR's are very nice. __________________ Need help with car audio or electronics? Let me know!! Need Help Let Me Know Direct email address reimermatt@gmail.com Owner of: Dynamic Mobile Audio Follow me below https://www.facebook.com/Dynamicmobileaudio/

04-19-2010, 10:48 AM	#2 (permalink)
speedfreak28 Base Member Join Date: Jul 2009 Location: south jersey Posts: 247 Drives: 05 ram, 79 z28 Rep Power: 17	Lol, dunno why your so bent out of shape because I said there were a ton of cheaper, better options than your focals. Just because you bought an overpriced set of components doesn't make your car an award winning sq install. I'd love to see the how you have the speakers imaged and how the wires are ran and terminated. SQ is a lot more install then product used. Last edited by speedfreak28; 04-19-2010 at 10:55 AM.

04-19-2010, 11:53 AM	#3 (permalink)
2fast4thelaw Enthusiast Member Join Date: Feb 2009 Location: Denver Co Age: 51 Posts: 403 Drives: 09 370Z Sport/MT6 Rep Power: 17	There are many photos and unique designs in my audio system on this site that speak for themselves. Everything in my car has been designed and engineered specifically for my car. I have even shared my subwoofer enclosure design with some of you that took countless hours of design and engineering. I had to have a shop do the fabrication and installation because fo one, I dont have a Machine shop and a wood shop at my disposal anymore, next I didnt have the time to strip my car down to deaden it. I have done both active and passive cossovers on my fronts and I actually gained better results from the passives but my passives have been modified and redesigned by me to taylor them for the interior of my car and the thier location. So dont go there buddy! You are outta your league. __________________ To the optimist, the glass is half full. To the pessimist, the glass is half empty. To the engineer, the glass is twice as big as it needs to be.

12-22-2010, 08:15 PM	#4 (permalink)
37Z Enthusiast Member Join Date: Jun 2009 Location: Florida Posts: 476 Drives: 370Z MB 6M -sold Rep Power: 264	Sub enclosure in hatch in front of rear cross bar [QUOTE=2fast4thelaw;503671]There are many photos and unique designs in my audio system on this site that speak for themselves. Everything in my car has been designed and engineered specifically for my car. I have even shared my subwoofer enclosure design with some of you that took countless hours of design and engineering. Have you designed a sub enclosure in the 370Z hatch area located in front of the rear cross bar area (i.e. where the foam piece is located)? It may allow a 8" sub if the top of the sub enclosure is angled. I plan to install the amp (JL Audio HD 600/4 or 900/5 for its size) in this location as well. I plan on making the sub enclosure out of composite RFP (i.e.lightweight,dense,able to form curves). Any sub enclosure design thoughts would be appreciated! I can PM back with pics.

04-19-2010, 01:05 PM	#5 (permalink)
bigaudiofanat Car Audio Installer Join Date: Jun 2009 Location: Magnolia DE Posts: 8,342 Drives: 2012 Infiniti G37x Rep Power: 854	LOL speakers tailored for your car, doubt it. How they are aimed and setup that is something that I would believe. Speed knows what he is talking about and someone I talk to a for advice. So chill out! __________________ Need help with car audio or electronics? Let me know!! Need Help Let Me Know Direct email address reimermatt@gmail.com Owner of: Dynamic Mobile Audio Follow me below https://www.facebook.com/Dynamicmobileaudio/

04-19-2010, 01:51 PM	#10 (permalink)
jikhead Enthusiast Member Join Date: Jun 2009 Location: Little Rock, AR Posts: 425 Drives: 09 370Z Blue 6spd Rep Power: 185	Is this an East Coast vs. West Coast thing? Haha!

04-23-2010, 01:05 PM	#11 (permalink)
sobewebmaster Base Member Join Date: Feb 2010 Location: Wichita, KS Posts: 16 Drives: 11 Honda Civic EX cp Rep Power: 16	I'd like to throw in a suggestion for the component speakers, Infinity Kappa Perfects. Should be about the same price range as the Type-X. Your best bet would be to hear them in person somewhere, like an audio shop. I love Alpine products, I have a complete Type-R setup (including vPower M500 mono amp & F300 4chan. amp, 12" Type-R sub, etc. etc.) and I absolutely love it. But I would really say, after hearing the Infinity Kappa Perfects powered from an Infinity 500w multichannel amp in a friend's GTO, I was just shocked at the clarity at high volumes, not to mention the bass they provided as well.

04-27-2010, 03:07 PM	#12 (permalink)
fuct A True Z Fanatic Join Date: May 2009 Location: Sugar Land Posts: 3,692 Drives: 97' Ranger :) Rep Power: 25	so that NISMO audio upgrade.... hows that thing coming?

04-27-2010, 06:44 PM	#13 (permalink)
speedfreak28 Base Member Join Date: Jul 2009 Location: south jersey Posts: 247 Drives: 05 ram, 79 z28 Rep Power: 17	pm sent. yea thats the problem with alot of programs is that a home audio environment is way different and makes it tons easier to use a passive network.

05-11-2010, 07:43 PM	#14 (permalink)
speedfreak28 Base Member Join Date: Jul 2009 Location: south jersey Posts: 247 Drives: 05 ram, 79 z28 Rep Power: 17	I agree with 2 fast, 12w6v2 and the 900/5 is a great start, that is 500rms and the amps use regulated power supplies and put out that power from 2 ohm to 4 ohm

05-17-2010, 02:46 PM	#15 (permalink)
rockhounds Base Member Join Date: Apr 2010 Location: Miami/FL Posts: 67 Drives: 2009 GT-R Rep Power: 16	Hey guys, quick question... I'll be installing the audio system by myself and I was wondering how can I install the tweeters. As I said, the Focals 6.5" support 75WRMS + the tweeters. I 'm thinking about bridging the 4 channels of my JL HD 900/5 into 2 channels but I don't know how to configure the crossover in order to avoid problems blowing up the 6.5" if I hook them up in series with the tweeters. Any suggestion? Thanks! __________________ “Three Rules of Work: Out of clutter find simplicity; From discord find harmony; In the middle of difficulty lies opportunity.” - Einstein

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