[MattSelinger]

Best place I can think to get input on this is right here in the GR-Research community:

I have a 2020 Toyota Tundra and I want to keep the sound system as stock as possible while also doing a little to make the sound better.  Basic question is this... could I expect to hear more detail and clarity from the stock dash 2.75" speakers if I change the 100 uF electrolytic capacitors with a decent quality poly type capacitors and would adding a bypass capacitor help the cause?

More details for those interested:  The dash speakers are 2.75" paper cone speakers with a 100 uF garbage capacitor on the positive lead.  They are 4 ohm and my calculations say the 100 uF capacitor is doing a simple roll off around 200 Hz.  This particular vehicle has a center dash speaker (dual voice coil) that many folks on the Tundra forums suggest to disconnect.  I disconnected it and that definitely helped improve LT/RT separation.  Weird they put a "mono" speaker in the middle.  Also, the door speakers in the stock design is essentially a woofer that rolls off around 300-400 Hz. 

One thing I put some time into so far is applying sound dampening material to the doors.  This made a big improvement to the overall sound and quietness of the ride.  First time I have done this to a vehicle and I highly recommend it as a first step in any car sound improvements.

Much appreciation for sharing experience and thoughts to help.

Background:  I have built X-LS Encores, NX-Studios, Desktop Minis, and several Parts Express kits and I have modded/rebuilt several crossovers and heard the difference quality components and bypass capacitors make.  Many thanks to Danny, Hobbs, Ron - you guys have helped me to enjoy music and sound more than I could have without your "paying it forward" kindness.

[czechm8]

The sound deadening will help a lot.  I would put your money into some replacement drivers.  The stock JBL, or whatever Toyota is using are not good drivers.
Went through the same thing you are doing with my '05 Sequoia a couple decades ago - ended up scrapping the entire JBL system and built my own. 
I thinkt he bottom line is that those stock drivers wouldn't know the difference from a qualilty cap and a fire cracker.

Just recently wen through replacing all the drivers in my '18 Audi SQ5 with the B&O system.  Head unit and amps are quality, but the stock B&O drivers are cheap crap.  Made a huge difference.  It's actually enjoyable now!

[Early B.]

I would put your money into some replacement drivers.

Agreed 100%. If you want better sound, you gotta toss the garbage stock speakers. Don't waste time and money upgrading caps. 

Caution: you can easily go down the rabbit hole and add amps, subs, replace the head unit, etc. Next thing you know, you'll look up and your bank account has $2,500 less money in it. So if you want to keep the sound system as stock as possible, then "do nothing" is an excellent option.  If you feel you have to do something, then sound deadening will make an audible improvement.

[Doublej]

I too would toss the existing drivers. Check out the Crutchfield website for lots of great detailed information on upgrade options for your specific truck.

[toocool4]

It’s funny, even when you spent a lot of money on an expensive car like a BMW, Mercedes etc they only put cheap and nasty drive units in them.

[MattSelinger]

Much appreciation on the suggestions and comments.  Totally agree the existing drivers are cheap junk.   Replacement is a good idea but my concern is the stock head unit has some dsp stuff going on that is working to enhance the behavior of the cheap stock drivers.  Putting in good dash speakers could create a new problem of stock radio dsp doom.

Sound deadening is done.  That helped a ton and gave me the hope I could tweak the system instead of full replacement. 

I am choosing to experiment….  I am focusing on the 2.75” dash speakers.  I ordered new caps so I will test the stock speakers with decent quality capacitors to see what I can hear. I will also measure the stock speakers response and try to match their spec and curve with something new.    Then depending on that outcome, I will put in new speakers with the good caps. 

I will report what I find for those interested.

[czechm8]

Sounds like a good plan. 

[Tone Depth]

It seems to me that a mono center speaker probably evens out the sound left to right, and taking it out creates uneven sound levels. Think of it this way: left plus right equals mono.

This particular vehicle has a center dash speaker (dual voice coil) that many folks on the Tundra forums suggest to disconnect.  I disconnected it and that definitely helped improve LT/RT separation.  Weird they put a "mono" speaker in the middle. 

[MattSelinger]

It seems to me that a mono center speaker probably evens out the sound left to right, and taking it out creates uneven sound levels. Think of it this way: left plus right equals mono.

Good point Tone Depth.  With the stock "mono" speaker in the center of the dash the experience is a "wall of sound" from the front with almost no stereo separation (meh).  Disconnecting the center speaker changed the sound to a much more perceptible left and right sound field... more enjoyable for my listening experience. The stock door speakers are woofers running from about 250 hz down.  No real stereo separation comes to you from the doors in this stock design.

[vondy]

I have no experience with these guys but some folks in various Toyota forums like them.

https://oemaudioplus.com/toyota/#dica_divi_carouselitem_13

Seem to be high quality and plug and play for the most part.

The systems are design for the specific vehicle.

[czechm8]

I put a system from them in my FR-S.  They are great!  About as Plug n Play as you can get.
I would go for it if they make components for your vehicle.

[Digi-G]

I've done something similar as I wanted it to LOOK like it was stock.  I left the head unit and replaced all the speakers, 4 in my case.

I also added an amp.  I don't think you're doing new speakers any favors by driving them with the 5-7 watts that a stock head unit delivers.  New speakers along with a new 100-150 watt amp was magical.

[MattSelinger]

I've done something similar as I wanted it to LOOK like it was stock.  I left the head unit and replaced all the speakers, 4 in my case.

I also added an amp.  I don't think you're doing new speakers any favors by driving them with the 5-7 watts that a stock head unit delivers.  New speakers along with a new 100-150 watt amp was magical.

Digi-G - Can you give a little more detail on your method?  The 2020 Tundra (non-JBL) has dash speakers (2.75") run from the head unit.  Also there are rear door tweeters that are run from the head unit.  Then there is a stock amp under the passenger seat that runs the 4 door speakers which seem to be crossed over around 300 hz for the front and not sure what frequency the backs are low passed.

Did you rewire all speakers from a new amp under the seat?

[MattSelinger]

I have no experience with these guys but some folks in various Toyota forums like them.

https://oemaudioplus.com/toyota/#dica_divi_carouselitem_13

Seem to be high quality and plug and play for the most part.

The systems are design for the specific vehicle.

Thank you for sharing this Vondy...  They have a system for my vehicle and it looks like a well thought out system.  Price tag looks to be around $1,600 which does not meet the WAF (wife approval factor) and it also violates the 3KIC budget calculations (3 kids in college).  Ha Ha! 

[Digi-G]

Digi-G - Can you give a little more detail on your method?  The 2020 Tundra (non-JBL) has dash speakers (2.75") run from the head unit.  Also there are rear door tweeters that are run from the head unit.  Then there is a stock amp under the passenger seat that runs the 4 door speakers which seem to be crossed over around 300 hz for the front and not sure what frequency the backs are low passed.

Did you rewire all speakers from a new amp under the seat?

I had an installer do the work.  It was a 2005 Jeep Liberty.  In my case they installed the amp on the back of one of the rear seats - I didn't have room underneath the seat.  The seat was still able to lay down.  Pretty sure they were able to plug in to the factory plug from the radio/head unit.  And yes, all of the speakers were wired directly from that new amp.  Mostly, I didn't want to run all the wiring, including the power line from the amp that went directly to the battery (iirc).  That was a heavier wire and trickier to conceal.

I no longer have that vehicle but I was very happy with the install and thrilled with the sound.  The amp and speakers were Infinity / Kappa.  Four speakers and a single 4 channel amp.  Price around US$1500, maybe US$1600, including installation.  Almost 20 years ago!

Good luck with your project.

[MattSelinger]

Here is the update for those who are interested:

Reminder of my goal:  I have a 2020 Tundra SR5 (non-JBL stock system with stock amp under passenger seat).  I am wanting to improve the sound without changing the stock head unit or other major rewiring/amps/cost... Wife Approval Factor is key which also plays into budget$$.

What I did to start:  Sound deadening material on the four doors.  Siless Black 80 mil.  36 SF total used.  Cost $75.  2nd item was disconnecting the center dash speaker (essentially a mono speaker that kills left-right stereo separation). Cost $0.   These two changes were a big help.  Can's say enough good things about sound deadening treatment.

The next big item was figuring out how to get the 2.75" stock dash speakers to sound decent.  These stock speakers are 6 ohm and they have a 22 uF electrolytic capacitor attached... this cuts low frequencies at 6 dB per octave starting at 1200 Hz.  Several folks suggested changing the stock speakers.  So I did some research and identified a 2.5" speaker to test.  Actually I ordered two different ones.  A pair of Dayton 2.5" poly speakers and a pair of Peerless paper cone speakers.  These were both 4 ohm speakers.  If you do the math between the 6 ohm corner speaker and the 8 ohm center dash dual voice coil speaker... 6 ohm + 8 ohm in parallel is about 3.5 ohms.... so I figured 4 ohm would be good since the center dash is disconnected.  Also with a 4 ohm speaker I need a 33 uF capacitor to give the roll off at 1200 Hz... so I ordered a Dayton Poly Cap to cover this and - this might be overkill - I added a 0.1 uF bypass cap.  First test was with the stock speaker.  I bypasses the existing electrolytic cap with the Dayton cap and immediately noticed an improvement in clarity (A/B testing - totally could hear the difference).  It reduced the "smearing" or blandness of the sound from that little stock speaker.  More clarity...  That was interesting.  Then I compared the Dayton speaker to the stock speaker (no caps) and could tell the Dayton speaker was way better than stock.  Then I did some A/B testing between the Dayton and Peerless.  The Peerless won the test.  Next was 3D printing a mounting plate that matched the stock speaker shape.  My son took care of this.  Then I put it all together with some Red Wolf wiring harness connectors to keep from cutting or splicing anything on the truck. 

Results - oh my goodness is there a night and day difference in clarity, sound field, details.... Wow!  Overall I have spent less than $200 and it has taken the vehicle sound to a place where I am quite pleased to listen to music... even looking forward to it.  There has been a lot of talk at GR Research about small paper drivers and how they are killer for good sound.  This experiment with 2.5" drivers definitely peaks my interest in some of the new designs with the LGK speakers.

Thanks everyone for input and suggestions.  If anyone wants a parts list or more detail I am happy to provide more information.  Unfortunately I didn't stop and take pictures along the way.

Peace and joy!

[Early B.]

That's good to hear.

I have a Toyota Tacoma, and several years ago, I made the mistake of replacing the main speakers with coaxial drivers in the doors. I assumed the guy who did the work would know that he ought to remove the separate tweeters in the door, but he didn't. I also wasn't aware at the time that there were speakers on the dashboard. They should have been ripped out, too. I'm hesitant to DIY on my old truck.

[Doublej]

Excellent news. Please post a parts list for us audio voyeurs and if you have an image of the mounting plate post that as well. What software did your son use to create the mounting plate? TinkerCAD?

I contemplated a speaker upgrade for my CRV but lack the confidence to want to try removing the door panels.

[MattSelinger]

Parts list and some more details:

All parts ordered from Parts Express unless noted...
- Peerless by Tymphany TC7FD00-04 2-1/2" Full Range Paper Cone Woofer 4 Ohm
- Dayton Audio PC68-4 2-1/2" Full-Range Poly Cone Driver (did not use this driver..... the Peerless driver sounded much better to me)
- Dayton Audio DMPC-33 33uF 250V Polypropylene Capacitor
- Audyn Cap Q4 0.1uF 400V MKP Metalized Polypropylene Foil Crossover Capacitor (wired parallel to the 33uF capacitor as a bypass)
- RED WOLF Car Dash Tweeter Speaker Wiring Harness for Select Toyota Tundra 2007-2021 (Amazon)

Here is a picture of the stock speakers:
(while Toyota calls this 2.75" speakers... the 2.5" speakers I ordered have exactly the same size cone diameter)


We traced the speaker frame and my son used Tinkercad to create the template.  Print was made with a Bamboo printer:




Putting it all together... I used hot glue to secure the speaker to the frame template.  Connections were all soldered and shrink wrapped.  Sound has been way better than I hoped.