MJHSC400

I just finished wiring in a pretty high quality amp using the factory head unit and it's low level signals and remote lead--

I am using a MTX Thunder 4200x 75x4 (rated at 50x4, but birthsheets at around 70x4 actual rms power) -- The SC alt. is strong at 100 amps, and makes a solid 14v so any amp will come alive in this car.

Quality
The quality of these factory speakers is astounding to me-- The pods are appropriately tuned by an engineer who knows his stuff-- I put this amp on the two front speakers and am totally astounded by their output with the power upgrade.

The rears are also good quality, and are just fine left on the factory amp, but will work just fine on the rear 2 channels of a 4ch amp as well. They resemble an MB quart driver to my eyes... The sound quality will very likely be much better on the aftermarket amp you use if it's of any level quality though. Just cross them over well, and even use an inline capacitor to cross them over low pass at about 3k or so with just a simple 6db per octave setup (single capacitor, or maybe it's a coil I'm thinking of..)

I'm assuming these are a 4.5" or 5" mid, but I haven't measured them to be certain.

A 4" mid running free-air wouldn't come close to this output, and I don't think this effort the lexus/pioneer engineers put in to this system should just be gutted and used to fill a trash can.

The ported enclosure plays well down into the sub 100hz range, and can be easily crossed over at 100hz or even a little less-- the tuned enclosure will easily control cone movement at these frequencies--

A 4" mid also plays closer to the tweeter than a 6.5 ever could dream of-- as it has a much higher resonant frequency--

I am considering using my passive crossovers with some 28mm silk tweets in conjunction with these pods to really get a nice upgrade on the high frequencies--

The paper cone on these factory mids also makes for a very fast transient response, giving strong vocals, good musicality, and decent power handling with good resistance to cone breakup-- The paper cone has a very good natural dampening inherent to the material-- Most professional loudspeakers use paper cone drivers and belt out ear splitting mids due more to the cabinet design and voice coil/motor structure combination than anything..

What am I saying??

It may be surprising at how well these factory pods will perform with a little power on them, and it's probable that the sound quality and volume level will be more than satisfying.

Afterall

These are $50,000 cars for goodness sakes-- There has to be something above average about them..

Seize

Great write-up. I agree with you all the way, the system in my 93' GS still sounds awesome compared to my friends who have newer model cars even. I plan on adding a subwoofer in the near future just don't know what kind. Already got the Zapco sittin' under my bed for when I decide what sub to go with

MJHSC400

The more I listen to these factory tuned port front door enclosures, the harder it is for me to remove them for a free-air 6.5 -- even if they do handle loads more power--

Off to get a beer now--

jefthim

I too agree that the Nak 4" speakers sounded great, but mine are in bad shape. All 4 of them had rubber missing around the outer edge, but they still sounded great at lower volume levels though.

You know here in TX they have a saying "bigger is better." So with that said....every "Car Audio Expert" I have talked to encouraged me to put 6.5 componets in the front door panels. I have come to the conclusion that Lexus enginiers put 4" speakers in that car for a reason. I have tried two different pair of good quality 6.5 componets(Bostons & Focal) and neither pair sounded right to me. I am hoping(fingers crossed) to buy a set of 4" Focal K2Ps and see if that fixes my sound quality concerns. Last weekend I installed the Bostons in my Mustang and they sound completely different than they did in the SC. I wouldnt remove the Nak speakers unless you need to, and...if you do replace them I would not go with 6.5s.

MJHSC400

The resonant freq. of a 4" mid more closely matches the most common freq. found in music-- Trumpets, voice, instruments, etc--

The pioneer speakers in my car are 5" I believe-- but they're in a tuned port enclosure as yours probably are as well--

A 6.5 will play these frequencies just fine, but the door grille is going to kill a lot of the freq. you want to hear from the mid-- as it's a very small hole you're pushing sound through--

My solution is to employ a 3 way setup with a quality midbass in the stock mid location, but then to add a 4" mid directly on the door above the stock grille, below the wood trim-- This mid location will be almost directly between the tweet and midbass--

I will have to make a mesh/fiberglass grille of some sort to cover the mid and make it appear stock, but it shouldn't be too hard with some mesh, some time, and some grille cloth--

If you've ever seen BMW's factory 3 way setup in many of their mid 90's models my setup will resemble the same configuration--

This will solve the cancellation problem of trying to play high mids through the small stock grille--

The way the lex/pioneer engineers solved this problem was to tune the enclosure to favor high mids--

With any power on those front speakers you would see that the "mid" level needs to be swept way down to flatten out the response curve-

They did this to have strong and efficient midrange to work well with the low power 4 ch amp, as well as to use the enclosure to extend the mid's low freq. capabilities--

I think deadening the door will be a good step for a solid midbass, but the 4" mid from MB's old high end referenz line should bring the stage right where it needs to be--

Good luck man-- A 3 way setup will either cost you some money or some design time to set the xover points where they need to be--

I'm using components from a few different sets and an audio control 2xs to split the mid and midbass at 350hz / 18db/octave -- works real nice, though I would prefer to split them at 12db ---

cjones4640

nice write up..i just finish my 94 GS300 and the only issue i have is my box is too shallow...and the guy who had it before me had the beauty boards mounted so it had the bass staying only inthe area of the gas tank and sub hole (he had is subs firing to the front) but i let a well known installer in my area listen to give me his advise and asked me what speakers i had in the doors..when i told him they were the factory, he ask me can he take one of my doors off cause he didnt belive me...I for one think the sound great...

88supramki

ehhh, i guess i just love other speakers WAY too much to rock the stockers

MJHSC400

So, to avoid confusion, I am impressed with the factory mids, but the tuning they did to the cabinets in the doors is way high for my taste after a bit of listening -- The midbass is really good for a 92 model car -- the engineers in charge of the audio system took their time on this setup---

I'm interested more in setting up my custom 3 way set --

I just bought some cement board for countertops and flooring that goes under tile to build the mount panels for the midbass in the doors and will update on the progress as it goes....

The board is 1/4" yet very stiff and dense, much better than mdf -- and it won't add too much weight once it's cut to appropriate size... I'll use it to also cover the hole in the door for the window regulator--

As seen here-- (where the orange clear plastic is--)

FSUnoles

what if you enclose the 6.5 with the pod, you think that would improve the sq

88supramki

depends on the speaker. take Focals for example, they were never meant to be in individual enclosures. they were designed to be put in doors and using as much air space as they can get.

yes i got that straight from a designer at focal...there goes my thoughts of individual pods

MJHSC400

This is very true-- and most car audio mid/midbass drivers are designed with a taut suspension and maybe a heavier moving mass to compensate for no enclosure to control cone motion--

BUT-- these are typically very flat (IB enclosures) which is certainly not a bad thing-- but when you want to bring as much midbass up front as possible, this leaves something to be desired UNLESS you get some very high quality drivers and feed them very adequate power--

A sealed or ported enclosure will have a peak whereas the IB won't peak at all-- Also a sealed or ported can be tuned to a lower freq or higher depending on where you want it to perform best-- This tuning can be advantageous in a car door-- (probably why Lexus chose this design in the first place) A tuned port enclosure will allow your mids to have a greater sensitvity, where most of them lack (low sensitivity)

Basically an enclosure with the proper speaker/driver will provide more output with less power-- and this can allow you to tailor out wierd nuances inside the car environment -- Basically the increased sensitivity can be used to your advantage if you have a good eq in the mix to tailor the frequencies--

I'll put it this way--

The factory mids are freakin painful loud in my 92-- I've got about 65w each on them-- crossed over at 90hz-- and they take it all, maybe not well, but still-- They also turn a great deal of the power into good quality sound--

The factory tweets leave a little to be desired-- BUT they can be tuned a bit if you have a good eq-- I had an EQL in the mix last week for testing, and I was able to tune the tweets to a level that sounded awesome at normal listening levels (loud ) for a normal (awesome) [factory] sound system--

I will still be using my cement panels to build baffles and install my 6.5's in the doors though, and will remove the pods-- I think the 6.5's are capable of a little more midbass than these factory units--

If I ever get time and just feel like it I may mess with a ported enclosure with a morel driver or something like it-- a 4 ohm home audio midwoofer will perform well in a small tuned cabinet (constructed of fiberglass)

I am also in the design stages of adding a 3rd driver (4" MB Qt referenz mid) just under the tweet, just below the wood trim on the door-- For a nice and smooth 3 way setup--

(This 3 way setup gets LOUD by the way, but the quality is purely stunning well beyond a comfortable listening level-- )

Usually the difference b/t good and very good components (once your past a certain point albeit somewhere around the Polk DB quality level) is purely output and power handling capability, as well as a little sonic clarity at high volumes (uncomfortable for most) and a larger, smoother tweeter--

I've got my hands on some the Soundstream Exact 30mm hybrid soft domes -- I believe they were paired with a morel or dls driver with Soundstream's name on them-- so they are undoubtedly very very good-- The dome is a soft silk tweet with a very thin aluminum cap fused/bonded to the silk dome-- This design should kill a lot of harshness (which I hate) and play a little more accurately-- instead of having that tinny car tweeter sound we all know too well...

More later--