2017 Lexus RX 350 - Help with tuning aftermarket sound system

[DC4528]

Hey guys. Thanks in advance for your help as I'm a bit of a noob when it comes to car audio.

I had a shop install the following speakers in my 2017 Lexus RX350 and although it sounds good, I have a hunch that some additional tuning coupled with your guidance will allow me to unlock the full potential of the speakers.

Dash: Hertz Mille Pro MPK 165.3 1" tweeters
Doors (Front): Hertz Mille Pro MPK 165.3 6.5" woofer
Crossover installed in center console with wires running from each component to respective location on crossover (I believe it is a passive crossover)
Door (Rear): Hertz Mille Pro MPK 165.3 1" tweeters (top of door) and Hertz Mille Pro MPK 165.3 6.5" woofer (bottom of door)
Sub: Rockford Fosgate P3D4-10 in sealed enclosure
Amp: Rockford Fosgate P1000X5 amp
JL Audio FIX-86

Question specifically on setting gains, HP/LP, frequency, and punch EQ..

When I picked up the car from the shop, I noticed that my dash tweeters were crackling at higher volumes, which made me think either there was an issue with the crossover (defective) or it wasn't hooked up right. I spoke with the shop tech and he told me to adjust my gains in order to achieve the loudness I desired without distortion. Adjusting the gains in the front channel helped a bit, but still at high volumes it seems as though I'm getting some mids in my tweeter, which is causing it to distort. I have been told that these speakers can really bump and are very clear even at high volumes, but I'm not completely satisfied with the present sound I'm getting from the system. Should I be controlling the frequency (HP for highs) at the amplifier or set it to All Pass and let the crossover determine what frequency to send to each respective speaker? Also, the frequency on the amp goes from 50 Hz to 250 Hz, but the frequency range of the speakers is from 40 Hz - 22,5k, so I'm not sure how I'm supposed to set this to get the most out of the speakers. To combat the distortion at high levels, I'm having to turn the factory head unit EQ mids very low in order to 'help' with distortion, but I feel as though that's more of a band-aid and really isn't solving the problem.

Here's how everything is wired:

speaker wires going from head unit to factory amp (pioneer) - we had to integrate this into the setup in order for nav and other on board functionality to continue working. From there, the shop made a t-harness and connected the speaker level inputs into the jl audio fix 86. From the fix 86, there are 3 channel of RCA outputs going into the p1000x5.

Please let me know your thoughts on how to achieve optimal sound quality from my system.

Thank YOU

DC

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[Popwarhomie 5,000+ posts]

If the shop did the install take it back and make them fix it. Alot of money spent to not be happy

 

[DC4528]

Agreed....But it is quite far away and I don't have another car to drive while they tweak the system. Any suggestions on tuning for my system?

 

[Popwarhomie 5,000+ posts]

Agreed....But it is quite far away and I don't have another car to drive while they tweak the system. Any suggestions on tuning for my system?

Since you are using passive crossovers there isn't too much you can do. Should be set to full pass or all pass.

I personally would get rid of the rear speakers. Run the fronts active(no passive crossovers) and tweak the crossovers and EQ points with the DSP.

 

[DC4528]

Since you are using passive crossovers there isn't too much you can do. Should be set to full pass or all pass.

I personally would get rid of the rear speakers. Run the fronts active(no passive crossovers) and tweak the crossovers and EQ points with the DSP.

If it is set to FP or AP then the crossover between the amp and speakers should be filtering out the frequencies for each speaker (assuming it has been connected right), correct?

I don't have an option to get rid of the rear speakers as the return period has passed. Why do you recommend I get rid of them (full range)? What active crossover solution do you recommend? Which DSP solution? Is the FIX-86 have that capability?

 

[Popwarhomie 5,000+ posts]

If it is set to FP or AP then the crossover between the amp and speakers should be filtering out the frequencies for each speaker (assuming it has been connected right), correct?

I don't have an option to get rid of the rear speakers as the return period has passed. Why do you recommend I get rid of them (full range)? What active crossover solution do you recommend? Which DSP solution? Is the FIX-86 have that capability?

Yes the passive crossovers would take care of everything with amp set to full pass.



I say get rid of the rear speakers so you can run 4 channels to your front speakers. channel 1/2 for tweeters and channel 3/4 for mids. That way you bypass the passive crossovers and can use the DSP for tuning crossover points.

Another option would be adding another 2 channel amp for the rear speakers(keeping them on the passive crossovers) or adding a 4 channel for the fronts to run active.

 

[DC4528]

Thank you for the information. I'll take all of this into consideration. If I were to keep my system as is and select full pass on both the front and rear channels, does the channel frequency on the amp even matter at that point? If it does, what should I set the front, rear, and sub channel frequencies to (each one has a knob that needs to be set at some frequency).

 

[hispls 5,000+ posts]

I think pop has given about the same advice I would. Rear speakers are typically unnecessary and difficult to really build a good soundstage in a car with. If you were going to get into a big DIY project to try to run "active crossover" it's not like those components will go bad if you pulled the rears and just saved them for later. They're a premium product and if you kept them in a dark place and didn't crush them or something you could use them in another vehicle a decade from now or trade them into some other cool toys or whatever. Not like you bought junk here.

I think there is definitely a problem if your tweeters are straining though. Those components are meant to take 110W continuous and your amp should be delivering 75W (probably a little bit more being RF POWER series) but definitely not that you should be over-driving them.

Do you have some EQ settings that may be trying to over-boost some frequencies in the 1000-2000hz range? I really don't know anything about JL Fix so if that's doing something funny I can't really tell you how to fix the fix, but the passive crossovers on those components should have a -3db or similar switch in them that may help if the tweeters are being over-powered. Try to pop them open and see if that little switch helps you.