ForScan Flat EQ before key200.4?

[rallyshark]

If I were to get this and have it feed to an aftermarket DSP to an Aftermarket 5 channel amp, would if then make sense to run aftermarket wire from that amp to the Fronts/Rear or somehow reuse the factory wiring?

You could just run equivalent sized(good 18 or 16 gauge) wire back up to the front from the amp and connect to the factory speaker wiring going to the speakers. It should be fine, since the "processed" signal going to the factory locations wouldn't be carrying a ton of current. Sure, all new wiring all the way to the factory locations would be great, but not really necessary in your case.

What you're describing is what I did on mine. I used the PAC harness to access the factory outputs and ran that straight to the DSP, the DSP straight to 5 channel amp, then amp outputs back to the front and attached to the factory wiring going to the speakers, and sub output straight to the sub. I used 9 conductor speed wire to run the signal wires back to the amp and for the turn on wire and regular 16 gauge speaker wire for the amp outputs back to the front. Speaking of, make sure and use an actual turn on wire(especially for the hybrid). Using the signal sensing turn on will suck the 12v battery, because the truck sends voltage through the speaker wires at times even when the stereo isn't on. In other words, your amp and stuff will be powered on if you open a door or do anything with the truck(even when the truck isn't on and no key is present).

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[zach57x]

You could just run equivalent sized(good 18 or 16 gauge) wire back up to the front from the amp and connect to the factory speaker wiring going to the speakers. It should be fine, since the "processed" signal going to the factory locations wouldn't be carrying a ton of current. Sure, all new wiring all the way to the factory locations would be great, but not really necessary in your case.

What you're describing is what I did on mine. I used the PAC harness to access the factory outputs and ran that straight to the DSP, the DSP straight to 5 channel amp, then amp outputs back to the front and attached to the factory wiring going to the speakers, and sub output straight to the sub. I used 9 conductor speed wire to run the signal wires back to the amp and for the turn on wire and regular 16 gauge speaker wire for the amp outputs back to the front. Speaking of, make sure and use an actual turn on wire(especially for the hybrid). Using the signal sensing turn on will suck the 12v battery, because the truck sends voltage through the speaker wires at times even when the stereo isn't on. In other words, your amp and stuff will be powered on if you open a door or do anything with the truck(even when the truck isn't on and no key is present).

Have any photos for the setup?

 

[rallyshark]

Have any photos for the setup?

I don't have any that would really show you anything useful, since everything is hidden and I didn't take an photos while I was doing it. I have my amp/dsp mounted on the back wall of the cab. I'm using an Audio Dynamics DSP, going to an Audison 5 channel, Dynaudio components up front, Polk 2 ways in the rear, and a Hertz sub under the seat. I did some stuff the hard way, and had to modify the dash/doors for that component set. I don't want to clog up this thread with pics of my stuff either I'll shoot you what I have in a message.

 

[AVC]

And I did have my wiring out of phase when connecting the right rear pillar. Rechecking it all now will report back later as for now the first one I checked the right rear pillar wiring was reversed on the passenger side.

Yep, L+R summed at the sub amp, with one of them polarity flipped would pretty much cancel out the signal for most music types (where the LF is centered in the stereo mix). Would also explain the "bass jumping out" if the LF content was slightly efftects-spread or panned somewhat L or R for parts of a song.

 

[AVC]

Measured XLT power response curve at headrest, with Forscan set to "Flat EQ", Kicker subwoofer on, head unit tone control's at "0" neutral. (SEE post 62 for when tone controls are optimized)

Orange Area = contribution by Kicker subwoofer, xover set to approx 55 Hz

Purple Area = broad sag of LF-Mid energy making all content sound thin, lifeless and with collapsed imaging.

Cyan Area = the bump coming from rear speakers. When tone controls are adjusted to raise the purple area and yellow HF droop, this cyan area pops above the target curve

Yellow Area = HF sag

And below is the factory response w/ Forscan at factory default EQ, head unit tone controls neutral.

This was a very quick capture with an Android app, to get a sense as to why the factory system sounded the way it did. While not a "careful" measurement, it does illustrate:

An overall perceived factory sound of some thump, some warmth, receded, non-offensive low mid through high mid, then some sizzle at the top.

Purple trend line = the approximate real LF rolloff. The Android app was set for low res binning below 100Hz, so the data is falsely optimistic and rolls off MUCH faster in reality. Also explains why an aftermarket sub has very little LF to work with, as the level is 20dB+ lower than midrange levels and some 30 dB below the 60-70 Hz level. An aftermarket sub accentuates the already heavily boosted 60-100Hz (which you already have plenty of) and can provide virtually nothing below 55Hz that yo DO want.

The yellow ellipse = the 15 dB or so of net factory LF boost applied to ALL speaker circuits. The door speakers are the primary acoustic contributors of the boost.

Red trend line = the perceived power (listener) response. The measurement as shown is effected by comb filtering, as seen by the regularly spaced peaks at 125, 250, and again at 600, 1200.

The blue ellipse = HF peak in all circuits, which rear speakers somewhat respond to, but mostly picked up by the dash tweets.

 

[ChefJeff789]

Hi all,

Anyone with experience troubleshooting setups, I hope I have an easy one for you. I have an XL and swapped in some inexpensive RF speakers (R165-S for the fronts and R14X2 for the rears). Audio quality markedly improved when I first did the speaker swap almost 2 years ago, but I didn't realize until last week that there was an option for FlatEQ in ForScan (I just didn't look, stupid me). WOW is there a difference. The audio quality went from "a bit better" to "night and day"... with one issue. I'm not sure what is causing it, but there is a signal causing notable irritation. It feels almost like being on an airplane at altitude, and gives me a light headache on longer drives. I'm assuming it's a high frequency, maybe even a near-ultrasonic signal...? Anyone experienced this and know what I can do about it? I'm wondering if there is a simple audio filter I could install to get rid of this. I do not have an amp installed and would prefer not to have to run extra power to anything, if possible. I really don't want to lose the better audio, but I will if I need to.

 

[rallyshark]

To truly answer your question, we'd need to know what frequency this sound you're hearing is coming from, but... If we are too assume the sound is a very high frequency, I'd recommend turning the treble setting down and seeing if the issue is still there. If that gets rid of it, then you can move on with permanent solutions from there. Assuming it is a high frequency, you have a couple of options. Option one: Install an amp/dsp combo so you can tailor the frequency response to sound EXACTLY how you prefer. That would give you the ability to cut very specific frequencies at will, and this is option I would recommend. That would give you the ability to up your sound quality even more. The downside is extra cost, but the upside is better sound and flexibility. Option two: put a simple 6db(low pass) filter on every speaker at 15,000hz(complete guess on frequency) using a coil. This is a crude approach, and may or may not solve your problem. It would basically slowly cut your frequency response from 15,000hz up. You could also try doing it at 12-14,000hz too, if you want to buy more coils to try. You would have to look up first order crossover calculators online to determine the appropriate value/coil needed. I really don't recommend this approach, but it is the least expensive option.

I would try adjusting the treble setting in the factory head unit to see if I could find a compromise in getting rid of the sound and sound quality first, since that is free. That's just my opinion and I hope it helps.

 

[Toddman45]

Hi all,

Anyone with experience troubleshooting setups, I hope I have an easy one for you. I have an XL and swapped in some inexpensive RF speakers (R165-S for the fronts and R14X2 for the rears). Audio quality markedly improved when I first did the speaker swap almost 2 years ago, but I didn't realize until last week that there was an option for FlatEQ in ForScan (I just didn't look, stupid me). WOW is there a difference. The audio quality went from "a bit better" to "night and day"... with one issue. I'm not sure what is causing it, but there is a signal causing notable irritation. It feels almost like being on an airplane at altitude, and gives me a light headache on longer drives. I'm assuming it's a high frequency, maybe even a near-ultrasonic signal...? Anyone experienced this and know what I can do about it? I'm wondering if there is a simple audio filter I could install to get rid of this. I do not have an amp installed and would prefer not to have to run extra power to anything, if possible. I really don't want to lose the better audio, but I will if I need to.

You might be experiencing listening fatigue from the tweeters in your speakers I see your fronts have Mylar domes where the rears have silk dome tweeters usually the silk domes are a lot easier on the ears a more balance warm high frequency, where the mylar could be causing you issues after extended listening.

Thankfully I've never been one to experience this but I've read a lot that have on that issue with certain tweeters.

If you have your high frequency turned up in the radio setting you might try backing it off to the middle setting are very close to it, and see if that has any effect.

 

[AVC]

Hi all,

Anyone with experience troubleshooting setups, I hope I have an easy one for you. I have an XL and swapped in some inexpensive RF speakers (R165-S for the fronts and R14X2 for the rears).

with one issue. I'm not sure what is causing it, but there is a signal causing notable irritation. It feels almost like being on an airplane at altitude, and gives me a light headache on longer drives.

@ChefJeff789 Guessing the OEM amplifier is unhappy with the new 4 ohm front door speakers and 4 ohm tweets-- their spec sheet impedance. I know the OEM dash tweets are 8 ohm, and guessing the OEM doors speakers are as well. The door speaker and dash tweet is in parallel on the OEM speaker circuit, and with the R165-S components, they are presenting a 2 ohm or lower load to the circuit above 2kHz or so where the tweet comes into play.

The rear speakers may be making the rear amplifier circuits somewhat unhappy, as I assume the OEM's are 8 ohm and your replacements are 4 ohms, according to spec sheet.

Assuming a switch-class OEM amplifier (likely D-class H-bridge), the two most common instabilities for too low load impedance are bleed through of the ultrasonic PCM carrier, or amplifier instability with either high frequency oscillation or infra-sonic motor boating. The latter you'd can detect by putting a tissue on the door speaker grill and watching for flutter while playing low level content.

An oscilloscope across the dash tweet speaker lines would confirm the issue.

The fix? Removing the R165-S tweets and re-installing OEM tweets may raise the total circuit impedance enough to make the front amplifier circuits happy. Or use 8 ohm aftermarket speakers.

 

[rallyshark]

@ChefJeff789 Guessing the OEM amplifier is unhappy with the new 4 ohm front door speakers and 4 ohm tweets-- their spec sheet impedance. I know the OEM dash tweets are 8 ohm, and guessing the OEM doors speakers are as well. The door speaker and dash tweet is in parallel on the OEM speaker circuit, and with the R165-S components, they are presenting a 2 ohm or lower load to the circuit above 2kHz or so where the tweet comes into play.

The rear speakers may be making the rear amplifier circuits somewhat unhappy, as I assume the OEM's are 8 ohm and your replacements are 4 ohms, according to spec sheet.

Assuming a switch-class OEM amplifier (likely D-class H-bridge), the two most common instabilities for too low load impedance are bleed through of the ultrasonic PCM carrier, or amplifier instability with either high frequency oscillation or infra-sonic motor boating. The latter you'd can detect by putting a tissue on the door speaker grill and watching for flutter while playing low level content.

An oscilloscope across the dash tweet speaker lines would confirm the issue.

The fix? Removing the R165-S tweets and re-installing OEM tweets may raise the total circuit impedance enough to make the front amplifier circuits happy. Or use 8 ohm aftermarket speakers.

All the factory speakers are 4 ohm, except for the tweeters in the dash.

 

[AVC]

Visual proof of that (for reasons other than this thread)?

 

[colinl]

Visual proof of that (for reasons other than this thread)?

people did look at the speakers and did resistance tests on them about 3 years ago.

the only 8 ohm speaker is the center channel on B&O trucks. the rest are 4 ohm. you can believe us, or you can go chase down pics and part numbers.

 

[AVC]

Yes, that is my ask; a post link to that info, rather than sifting through random threads for "ohms" or something. The dash tweets were actually impedance marked.

 

[AVC]

All the factory speakers are 4 ohm, except for the tweeters in the dash.

So my comments still apply in principal; a 4 ohm dash tweet in parallel with an aftermarket 4 ohm door speaker, may be disagreeable to the amp circuit, especially if the tweet impedance dips low where it overlaps a low impedance point with the door speaker.

Anyone come across Z sweeps of the mentioned aftermarket speakers, that Colinl would like us to "where's waldo" search for?

I know quite a few speakers over the years that despite a spec sheet rating of say 4 ohms, had significant low points in their impedance curve of half that Z or lower, making some amplifiers very unhappy/unstable.

The OP complained of unusual sensations after speaker replacement, and this scenario is plausible, IMO.

 

[colinl]

So my comments still apply in principal; a 4 ohm dash tweet in parallel with an aftermarket 4 ohm door speaker, may be disagreeable to the amp circuit, especially if the tweet impedance dips low where it overlaps a low impedance point with the door speaker.

Anyone come across Z sweeps of the mentioned aftermarket speakers, that Colinl would like us to "where's waldo" search for?

I know quite a few speakers over the years that despite a spec sheet rating of say 4 ohms, had significant low points in their impedance curve of half that Z or lower, making some amplifiers very unhappy/unstable.

The OP complained of unusual sensations after speaker replacement, and this scenario is plausible, IMO.

right. yeah, no. just because it's not technically impossible does not make it plausible.

the stock tweeters and door speakers are 4 ohms. you're welcome to dig around for incontrovertible proof, whatever point it would serve considering this thread involves installing and amp and speakers. (hint: there is none.)

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