DIYMobileAudio.com Car Stereo Forum banner

DEX-P99RS Ongoing Review and Discoveries

307K views 1K replies 184 participants last post by  phuoctue 
#1 ·
Land vehicle Vehicle Car Vehicle audio Compact car


Vehicle Car Vehicle audio Technology Multimedia


Vehicle audio Multimedia Electronics Car Vehicle


Installed it on Saturday Feb. 18th.

Biggest discoveries after a couple of days to listen-

1) The quality of the sub bass is as good as I could ever want and matches exactly my preference for excellent subwoofer bass. It sounds so much deeper, tighter, fuller, more accurate and correct than my previous head unit (Pioneer DEH-P8300UB). I didn' change the amp, the gains, nothing. Just the headunit and one complete auto tune session with custom network.
I don't know where the credit should go but I have to believe the ultra steep cutoff slope at the crossover provided by the units processing (80Hz, 36db per octave) has really tightened it up immensely. This improvement leaves me unbelievably impressed. This head unit all at once made my subwoofer and amp that much better.

2) Just one auto EQ yields much better sound, stage, accuracy, centering, clarity etc. than the best tune I could achieve with several months owning my old head unit.

3) I ditched the auto time alignment. It seriously detracted from the sound. I will revisit some form of manual TA as time allows- but with former head units I never found it to be a plus.

4) Biggest so far- the clarity of the sound allows the volume to be turned up significantly louder without fatigue or harshness! Again, no change in amp or gain settings- the ultra clean signal this source unit puts out lets me really really crank the volume much more than my old head unit.
This tells me that a "good" head unit with decent specs is not all it is cracked up to be- and that specs do not tell the whole story. I thought my old deck was a decent sounding CD player and pre-amp, it had great SN specs, had a 24 bit DAC, etc. just that it didn't have audiophile features like parametric EQ, time alignment, etc. It had 5 channels, adjustable high and low pass filters, subwoofer level, etc.
The DEX 99-PRS literally blows the old head unit out of the water- it made my amp and speakers so much better and louder!
It is really unbelievable and a bonus that I was not expecting.
 
See less See more
3
  • Like
Reactions: zech912
#2 ·
Nice write up, you'll have to keep adding to it once you get it dialed in even more.
They are sexy aren't they.:D
 
#3 ·
You didn't find the 36db per octave slope a little cold? I had previously had a 800prs, and I had the sub stage on 30db, but 36 on the p99 is so precise it takes a bit too much warmth out for my liking. I cranked it back to 24 at all points except the the tweeter low pass, which is set at 36db. That makes such a huge difference and reels in a lot of the harshness that comes with some tweeters natural top end roll off.

Does the auto EQ effect any X-over network settings?
 
#5 ·
You didn't find the 36db per octave slope a little cold? I had previously had a 800prs, and I had the sub stage on 30db, but 36 on the p99 is so precise it takes a bit too much warmth out for my liking. I cranked it back to 24 at all points except the the tweeter low pass, which is set at 36db. That makes such a huge difference and reels in a lot of the harshness that comes with some tweeters natural top end roll off.
yeah I'm starting to notice this- especially with my Focal tweeters- but the bass sounds so good!

i plan to attempt to fix this when i'm able to get some quality tuning time in- hopefully by adjusting the 80hz+ EQ range / slope settings etc. for the mid bass drivers.
-

does anyone have the HD radio module with the DEX? I would like to know if it allows the DEX to display the RDS info like my old HU did.
-
i did notice some weird things in the auto tune settings-
the time alignment modes all drastically lower the subwoofer output level. I bumped up the SW level and the TA actually sounds much better- such a wide stage, it really is nice although I have more work to do.

autotune also reversed the phase of the subwoofer. it sounds great so I'm leaving it this way for now.

-
with such a clean signal output as mentioned in the first post above, allowing the volume to be much higher and less fatiguing than my old "decent" head unit despite its reputable specs and the same amp / gain settings, i would speculate that this DEX unit offers a sonic advantage over systems using a decent or factory head unit and an external signal processor to do the work.
 
#4 ·
No, not if you set custom network, it only does eq and TA. You can set all your x-overs and slopes prior to using it.
 
#7 ·
if you are having to have a 8db reduction on your tweeters, why not lower your gains on those channels and run it without any need for attenuation.

i see a lot of people doing this and not maximizing their noise floor. doesn't make sense to me:p
 
#8 ·
I actually asked the same thing in another topic in dumb question. I will be doing a new install in the next few weeks and I will lower the gain from there, probably down to (expected output) around 25W and see. I was setting the gain at 150W(24.5V)@3/4 volume with 1k tone on all of my channels at that time.
 
#9 ·
This confirms that it does not take much power to run tweeters effectively. I wish they had some ultra portable 2-channel amps you could easily wire and power and install behind or under the head unit to drive tweeter channels. Something like the small Alpine power pack or the amp that comes with the Japanese DEX. This would really simplify matters, especially if you have rear door speakers consuming amp channels like my car does.
 
#11 ·
After a nice couple of hours tuning today I am really really pleased with the SQ of this unit and the improvement from my previous one.

The amazing discovery I made today was during the process of left right EQ centering of the (31) EQ bands using the individual test tones that a poster provided links to in the "ate my windshield" thread.

It is absolutely amazing how reflections, slight turns of your head, even moving your arm to adjust the control on the deck- can completely alter the volume and direction perception of those focused individual tone signals. Also amazing is how different frequencies behave and react so much differently- even than their "neighbors" in a given octave or range of frequencies. The experience of tuning these 31 individual frequencies left and right to center them was truly eye opening and nothing what I expected. As the poster of the "windshield" thread mentioned, my EQ looks jacked. One band needed a severe cut on the left / boost on the right to be centered, while the next band up needed just the opposite form of correction.
It is little wonder why most "SQ" stock systems rely on heavier bass and midbass and softened vocals / high frequencies to get their "pleasing" sound. I have now learned how difficult and (expensive) it is to properly tune a system for a vehicle. If you don't have left / right EQ, especially the 31 bands that the DEX has, I would have to believe that achieving a decent stage focus is an uphill battle at best. I am so glad I didn't wait for the new pioneer unit to come out that only has 16 band EQ.

I'm telling you, this experience was enough to make me wish for sound absorbing glass- that I could get rid of those unbelievably focused laser beam reflections that act differently from frequency to frequency.

The process was just as if a brilliant light bulb lit up for the first time- now I understand!

You play a tone signal, say 1.5Khz, and it seems to be coming from the right. Turn your head just slightly, and your right ear no longer hears the tone, it drops in pitch, and your left ear hears it. Absolutely fascinating. Not only do I wish for sound absorbing window glass, I now feel that I need to keep my head totally steady while driving!
 
#12 ·
If you don't have left / right EQ, especially the 31 bands that the DEX has, I would have to believe that achieving a decent stage focus is an uphill battle at best.
This is something I want to try for myself, and I believe it's going to be as eye-opening as dialing in time alignment well for the first time. Thanks for your remarks in this thread.
 
This post has been deleted
#14 ·
JL audio 900 HD 5-channel amp- all filters off except for infrasonic @ 30Hz.
Front doors= Focal 165 V30, running passive, tweeters in the upper front door panels.
Rear doors- Focal 165VB, passive, tweeters flush mounted just above the midwoofers.
Sub= JL 12W3V3 in a sonic electronix ported box which is nearly ideally tuned per JL specs, but I lined the enclosure with 2" thick polyfill sheets, careful not to block the port entrance, an additional 2" sheet on the wall opposite the sub.
 
#15 ·
it is probably having difficulty with the T/A since you are running passive front and rears.

scrap the rears and put those amp channels on your front stage. go active. then you will really hear a difference in the imaging and sq
 
#16 ·
thanks for bringing this up!

I did not like the original autotune TA settings because it drastically lowered the level of the subwoofer channel- once I adjusted it I am now runing with the TA settings for the LEFT seat- it sounds much better than without TA.

I did do the L/R EQ centering with the TA turned off, and then turned it back on once I finished the EQ. I dont believe these two items are in conflict. As long as the distances are measured at the mic with the ticking sounds (which are not full frequency spectrum) - it delays the signal accordingly.

--

I am fully ready to go active- and would love to find a nice small amp that I can put behind the head unit to run my front tweeters. I just do not comprehend what value this has for me. I am happy with the level of the tweeters, the passive crossovers are well suited for my drivers based on their frequency plots. What would I gain?

--
Regarding the rear speakers, or "rear fill" as some people call it, I definitely like the added mid-bass the rear door mid-woofers provide.

With the rear speakers on the "LOW" channel on the DEX, I did experiment with cutting the high frequencies out by setting a 2K crossover point for a low pass filter, 18db slope.
To me, and this is probably a personal preference, with all the high frequencies coming from the front speakers it sounded almost too precise, to easy to tell the direction of everything, and made the stage much smaller. I tried this for a day or so. Then I set the read door slope to "PASS" and let the high freqs through once again. Everything opened up, the stage became much larger, wider and deeper, even deeper forward, the vocals became "angelic" again, especially the female vocals. Call it ambience, or whatever but I am one that prefers this setup. It sounds much better to my ears, and I mean much better. My system is slowly becomming an SQ hall and I'm lovin it!
 
#18 ·
I have focal v165 vb components in the rear doors- tweeters are 12 o'clock 8 inches from the woofer centers. They are running about -4 db.

I am now running into a situation where the stage is too deep rearward on the right- getting too much exposure from the right rear tweeter making the stage have an L-shape accross the front and right.

I'll probably have to run a compromise where I start cutting the rear door high frequencies lower than pass but higher than 2K. This is a bummer but I can't avoid it- it is too distracting having the stage too deep on the right.
I am still not in love with a pinpoint front stage though with the rear tweeters completely cut. It just sounds too focused, too confined, flatter and less open.

When the rear speakers are properly blended, the sound stage still has left and right focus, it's repeatable but not so laser sharp. Much deeper and dispersed.

I know why most find rear "fill" a royal pain in the ass- more speakers, more amp channels, more HU channels, more expense, and more difficult to tune, but to me once dialed in it sounds better. You go to a live concert and you cannot have laser like sound directionality. Listening to a time aligned front stage sounds great but is not duplicating a live performance- it sounds more like a super deluxe boom box.
 
#19 ·
sorry but i completely disagree with that :p

a properly tuned front stage should not sound like a super deluxe boom box.
and most music you listen to is recorded in studio, not live performance.
even so, i know when i listen to mine, there is definitely no lack of depth or openness on live recordings.
it just sounds like you are having a slow transition in your tuning tastes and haven't gotten away from the rears yet.
also, having a pinpoint center should not deter from your imaging if its done right
 
#20 ·
When I first get rid of my rear speakers, I felt so strange. Once getting used to it, I have no more complaints and actually love it. I do all the same to my friends and refuse to install rear speakers to them. The always complain at first, then they stop after a while.

If it sounds like a super deluxe boom box you are probably doing something wrong. Can you tell us more about how the install and equipments are?
 
#22 ·
i threw out the boom box term only as a comparison- it sounds very very good with the highs cut from the rear speakers- but the image is definitely smaller and easy to pinpoint-
when i turn the high pass filter from 2K to pass, it opens up the depth of the sound. for example, a cymbal crash from the right tweeter is a foot wide when the rear highs are cut above 2K. when the rear highs are fully passed, the same cymbal crash is two if not three feet wide, splashing on he entire front door panel or so it seems.
just when i thought everything was perfect on the way to work this morning, it went to crap on the way home. when playing FM all of the vocals are now biased to the left- even after much L/R centering.
So I spend another hour trying to correct it- my ears are tuned out!
 
#25 ·
well i tried something smart today after still having a horrible image despite the L/R EQ centering exercise- it was somewhat OK with TA off but not so good when TA was turned on- and I have grown accustomed to the TA.
-
on a curious note, several tones in the upper midrange spectrum just would not center- and even seemed to get louder on the opposite side than the side i was boosting- many tones also started to "ring" and present a second tone on top of the first that also seemed to be on a different side than the non-ringing tone. i assume these were all cabin reflections- what does one expect trying to play musical tones in a small glass cubicle (from the arms up anyway).
-
regardless, i just re-centered all of the EQ levels and made them flat. since the original TA shifted everything too far to the right, i decided to give DEX's very smart internal brain another shot at getting the TA and image centered correctly- but played a little trick on it.
I made a "crash test dummy" out of pillows and a sleeping bag and a roll of shop towels for the "head". I tie strapped the mic to the vertical roll of shop paper towels which was set on the top of the "dummy". Before I did this, I carefully measured where my nose (center) and ears were using some reference measurements from the same surfaces of my car. I then put the mic on the dummy to represent where the center of my ears would be.
Because the original TA placed the image way right, I moved the mic center on the dummy a full 12" to the right of my previous autotunes when the mic was strapped to the center of my headrest. The 12" shift was an attempt to reduce the relative output of the passenger side speakers and increase the driver's side so as to shift the image to the left from the previous autotunes.

Well I it rip- still cracks me up that you need to operate the controls and read the faceplate when it's facing ceiling of my car- and I hoped my dogs would keep quiet and that no planes or trains would come by to upset the autotune.

When it was finished, I hopped in and checked out the results. Once again, the autotune really lowered the subs level drastically, but that was easy to fix. a week later and i can rip through the DEX's menus pretty well.
The new image was now to strong to the left- I had made some progress but overshot the mark. Easy to fix? Hope so.
I replaced the crash test dummy and this time moved the mic 6 inches toward the left, biasing it 6 inches to the right of the autotunes I did last week-end. Let it rip, and voila! The new image is nearly dead center! It sounds GREAT! I drove around for an hour playing tunes and am quite pleased with the results.
 

Attachments

#27 ·
All in all, this is a pillow that does nothing for the greatest impact on the rebound, and so have the driver's legs and not his body. just clip the microphone to the headrest (right) and move the seat forward a clove, then convert the indicated times at 0 Sub .Sorry for poor English ...
I greet
 
#29 ·
Dock-

I agree completely! My car is about the same internal size as a Journey and I did not realize how good the stock system was until I tried to improve upon it- My first "go round" of aftermarket hardware with basic 10" enclosed sub, basic amp, nice receiver (CDA 117) and what I thought were good comps (Alpine SPR 60C) actually sounder WORSE THAN FACTORY!
Of course, key to this was the fact that I did not amplify the rear door speakers.

I could not get the car to sound right without the rear speakers in the mix- it went to hell without them like your experience in the journey. the car's interior volume and acoustics are the reason- and the fact that the rear doors are much better bass enclosures than the front ones are.
I wouldn't know what to do to tune the system for front speakers only. At this point I don't see why I would want to- my car sounds great as it is.
The time alignment really helped.
 
#32 ·
I still say just sit in the vehicle during auto tune. This way, whatever effect you body has on reflections, blocking speakers, etc. is accounted for. You listen in the vehicle, tune in the vehicle, if your using the auto function as a baseline...be in the car. Lol :D
 
#37 ·
Another nice recent discovery is the ability to adjust the level of every channel independently.
I recently went active with the front stage after installing a new JL 300/V2 amplifier and the autotune became really finicky with the position of the mic trying to autotone all 8 channels. The final stage image would shift significantly right or left with just a slight shift in the microphone position- literally a matter of an inch or two to the right or left.

After about 5 tuning cycles I finally settled on one but it was not as good as when the front stage was passive.

The independent level control allowed me to fine tune the autotune results to balance the image.

I'm guessing you could improve the image even more by fine tuning the TA settings but I am hesitant to try it.
 
#38 ·
the independent level matching is a huge plus for tuning.

and don't be hesitant! you have a P99, come on! it is meant to be tweaked and fiddled with.
just write down your settings currently if you happen to mess it up.
 
#40 ·
Well an update for April 21. Last week I installed a class A-B amp to run active on the front stage. It sounds smoother than the class D that was running the fronts previously. There is LOTS of controversy about this opinion and I will not go into it here!
I also built my custom sealed enclosure for the JL 12W3V3 per JL specs. The thing is as solid as a block of granite! It fits in the sub trunk of my car and frees up the main cargo area. The SQ is surprisingly better than ported. I do get some floor vibrations but will correct that today with some velcro to hold down the cargo area floor.

My stage is still not centered very well despite a full week of tuning. Yes I even resorted to sitting in the car with the mic tie-strapped to my forehead and experimented with various positions. The sound sweeps are loud but tolerable but I am still not happy with the TA settings and image. The center fights me to stay hard left. All kinds of reflections to adjust for.
I'm going to attempt some manual TA adjustment today with my handy test CD and see how that goes. It's very frustrating.
Also when I am present in the car during the auto tune, the tonality is a lot more mid range dominant.
I'm going to stick the dummy back in and then attempt to tweak the TA manually.
Hardware is finished- tuning is a bummer!
 

Attachments

#41 ·
Update 4/22/2012.
After hours of experimenting with manual time alignment settings, I stumbled on a very simple way to dial in the settings after an autotune. First off, let me please say they I have never heard a car stereo sound like this before. It is a whole other world of sound quality once the stage is truly time aligned.
I had an Alpine CDA 117 before and could never get it to sound right so I never really understood how big of a benefit it can be for sound quality.
Basically I ran the "best" autotune sweep for mic position that I had achieved to date- although a per-the-manual autotune as a starting point would probably work.
Then I needed a decent source to play in order to fine tune the settings.
The articles I have read that suggest other methods (manual time alignment using noise and listening for the doppler effect, time alignment by finding the worst out of phase sound) somehow did not seem very easy to work with. All I wanted was for the image to be "centered" equally as to provide a nice stage. I know the autotune on the DEX really struggles with this, the image tends to wander all over the place, probably due to the amount of cabin reflections the various drivers and frequencies show.
So i thought, how do I center the image using time alignment? I really need to do this using music with my own ears because in the end that is what I am hearing when the system is in use.
I thought about using a mono source, since there would be no stereo or studio effects that alter the image position and that I would strictly be adjusting image to center it among the drivers.
AM radio was an option that I quickly dropped because it is not dynamic enough and has a limited frequency range.
I looked at my demo CD "My Disk" by Sheffield labs. It has a mono track of really dynamic, full range well recorded music. Unfortunately it is very short, so I put it on repeat track.
I then decided right or wrong that the "distant" speakers were somewhat OK per the autotune and decided to only adjust the left tweeter, the left midbass and the left rear passive. I wanted to see how this would work. The distances shown on the autoTA seemed reasonable for those farther away drivers on the right side and the sub.
I isolated the tweeters (mounted in stock position just below sail panels).
I changed the crossover to 3K so that they would play a decent range of frequencies.
First off, all levels were set equally and I had the balance position set to the right by (2) on the scale.
I played the mono track and began adjusting the distance settings of the left tweeter. I wanted to focus the tweeter sound to the center of my windshield. I listened carefully as I heard the image go from left to right and back again just by adjusting the left tweeter TA distance.
When I was happy with the center of the tweeter image, I then turned them down and isolated the front mid-bass drivers, located on the bottom front door panels.
Whoaa- this image was really biased to the left. No wonder the stage was crappy.
I again set the mono track on repeat and adjusted the distances on the left mid driver only.
It was a lot easier to center than the tweeters. I quickly had the midbass drivers centered with time alignment.
Then did the same to the rear door drivers. These were already close to center so it did not take too much to adjust he left rear driver to center the rear image.

I then adjusted all crossover points to normal as well as the levels.

Then I played one of the demo tracks (stereo) on the Sheffield labs disk-

I actually shouted out loud in my car in my garage when I heard it for the first time. Un believably amazing. Seriously, I have never heard this before ever- anywhere. I played the FM and a few CDs. Completely blown away. A whole new league and dimension to the sound. The highs are so much brighter but somehow smoother and more natural. The vocals are dead center in my windshield. The left / right stereo effects for instruments or other studio tricks pop out with precision- a keyboard pops out left of center- stays right where it should- and sounds clear and amazing. A guitar springs up to the right of center. Cymbals crash on the far right.
Simply astounding- and very easy to get to using a high quality dynamic full range mono music track.
DEX owners- be prepared to be blown away if you have such an opportunity.
 
#42 ·
Congrats, I know the feeling. But would you believe there may be even more to be had? The method using the noise (listening for doppler effect) not only centers your image but it also makes sure the tweeter is in phase with the mid, the mid in phase with the sub etc. So while you have the mids adjusted L and R try the noise method on the tweeter/mid first on the left side and then adjust the right side, (don't change the mid TA, just adjust the tweeter).
You will be in audio heaven soon :laugh:
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top