MartinC2S

Question about the tweeters. I'm going to be replacing mine with the ones that come in the JL Audio C5-525 kit. When I took mine off I noticed that there's a resistor that's been soldered in there. What did you do with it? Did you move it over to the new tweeters or just tossed it out?

bcameron59

If your JL is a component kit it probably uses external crossovers; if so you shouldn't need the original crossover resistors, capacitors and/or RF coils.

M. Schneider

MartinC2S - IIRC only the pillow style framed 130mm mid-woofer is being utilized from the JL Audio C5-525 kit currently. The Noika amplifier continues to power your 993's HiFi ?? That said, the door tweeter's signal continues to be of a low, low power variety. .... not at all likely to require protection if driving the tweeters from the C5-525 kit.

As an aside, any passive frequency dividing network or "crossover" sacrifices much of an amplifiers output spec., ..The amp's output goes puff, down the crossover drain. Active, active and active...is the way to go!

I'd like to send you a couple of Vifa tweeters to use if your 993's HiFi is powered with its original Nokia amplifier arrangement. PM if interested. My treat. These particular Vifa models (ring radiator) are modestly priced ($22. ea USD) and I'm guessing these will become the "go-to-tweeter" when a simple HiFi upgrade is targeted.. (not unlike how the 130mm JL- mid-woofer has become a known #490 HiFi enclosure fitment) When instructed actively the Vifa tweets do the trick and for little money, all the while fitting the 993 stock door tweeter pods. Stealth, do no harm.

MartinC2S

Mike, thanks for the info. I was under the impression that the tweeters could be utilized as well but then again I could very well be wrong.

And yes, I still have the Nokia amp powering my system. I've asked Josh for a Nokia connector so phase two of the project will be to replace the amp. I'll probably leave that project for the winter. Phase one is new Dynaudio and JL speakers in the doors.

I'm definitely interested in the tweeters. I'll send you a pm.

bcameron59

Note that the Nokia amp in the hifi setup has built-in crossovers to the front speakers, so there are 2 sets of wiring to the door pods:
- one is low frequency, only to the drivers
- the other is full range, to BOTH:
- a. the 3" medium size - but full range- speaker, and also to
- b. the tweeters via a passive xover concealed inside the pod

If you retain the Nokia amp with the new speakers you will probably want to use only the full range wires, hooked up to the new crossovers, which will have separate outputs for the driver and tweeter. The crossovers can be concealed behind the pod covers, however you may want to omit the pods and mount the driver directly to the door. The pod cover can still go over top of the whole setup, otherwise you may have unsightly indentations in the vinyl on your dooor cards.

However, the nokia amp is, to put it charitably, rather anemic, so a replacement amp is highly recommended to drive your JL speakers. If/when you replace the amp you can move your new crossovers under the seat and now take advantage both sets of wiring, one for driver and the other for tweeter. Check out this thread for excellent info on the wiring hookups:

https://rennlist.com/forums/993-foru...fi-option.html

Good luck with your setup!
Cheers/Brian

Silver Surfer

Mike, do you recommend the Vifa tweeters over the JL Audio tweeters included in the C5-525 set when using the stock Nokia amplifier? If so, why? Are they a better plug and play solution? I purchased your VW speaker pair (thanks!) and I planned to purchase the C5-525 set.

M. Schneider

Hey Brian -

I don't follow your notion of "crossovers" located in the 993 HiFi options door located speaker pods. Please advise.

Thanks

P.S. Not the single resistor tied to and at the leads of the tweeter??

bcameron59

I wanted to use the pods and original connector and wiring therein, when I was tracing the wires back to the speakers, I came across a larger capacitor inside the wiring pods. See pic below, the large cap is inside black heatshrink with green wires, also shown is smaller cap on the back of the nokian tweet. I did not make note of which of the two speaker circuits they were on, but cut them out because the polks I installed already had passive xovers.

M. Schneider

O okay. The inline wired shrink wrapped capacitor as a "crossover" of sorts . More of a pad.

No worries, got it. I'd guess this is fitted to front signal legs of HiFi systems where the Nokia DSP version module is present.

bcameron59

Pretty crude crossover, alright. Think it might have been on the midsize 3" full range, in which case looks like they were trying to filter out some of the bass.

Mine doesn't have DSP, though I guess it's possible it was removed by PO. Do you happen to know if there is a separate option for it?

Spyder_Man

Looks to me like those small in-line capacitors are there to filter out the lower spectrum of frequencies from reaching the tweeter. As I understand the setup (mainly based upon other's writings here on RL) both the 3" mid-range speaker and the tweeter are sent the same signal from the OEM amplifier (i.e. they're spliced off a shared channel of the amp) so without these capacitors the tweeters would be receiving frequencies that are too low and would damage the speakers. I am guessing the "cross-overs" within the OEM amp are simply splitting the mid-high from the mid-low (i.e. mid-high to the 3" and tweeters, and mid-low to the 5.25" door speakers). Also from what others have written, the rear speakers get an unfiltered full spectrum signal from the amp, though it wouldn't surprise me if they're just getting the mid-high signal too since those rear speakers aren't very big.

Most modern speaker set-ups are are 2-way systems designed to pair a mid-woofer and tweeter, skipping the use of a dedicated mid speaker. If you are splicing in a 2-way set-up with a passive cross-over, replacing the amp with a new one, and still hoping to drive a 3-way door speaker system, you'll be in for problems. The passive cross-overs aren't going to filter the signal at the same points as the OEM setup did. This is why Mike keeps harping on using a active cross-over setup with a real, modern Digital Sound Processor (DSP) so you have full control of the cross-over points and slopes and each separate channel coming from the amp.

In conclusion here are the main/best options that I see for repairing/upgrading the 993 Hi-Fi door speaker setup:

A) Just get fresh OEM components as needed and use the OEM setup - $

B) Replace some of the speakers with better modern speakers, but use the OEM amplifier (likely to damage the new speakers over the long-term with the underpowered OEM amp) - $$

C) Disconnect the mid-speaker and install a 2-way aftermarket speaker setup with passive crossovers and a new amp to drive the 2-channel setup (4-channels if you want to keep using the rears) - $$$

D) Go whole hog and install a 3-way door setup with new speakers, new amp(s) and new DSP to provide active crossovers - $$$$$

bcameron59

That pretty much sums up what has been posted, but what puzzles me is why 2 capacitors (high pass filters) on the circuit with midsize and tweeter. The cap on the tweet is pretty standard, but why the bigger cap on the midsize? Maybe that circuit is actually passing full range from the amp after all, not just mid-high, ie no crossover at the amp at least on that circuit. Might be a low pass coil on the bass driver circuit inside the amp but haven't looked inside it, perhaps someone else has had a look and / or posted pics of the original circuits.

For me, it's a moot point because I went with your option C) above (excellent summary, by the way), ie, Sony 50x4 amp with polk db6501 components in front (tweets replace nokia inside original housing), energy 4x6 plates at rear.

The one variation I am going to try out is to run a speaker level output from the CDR-220 to a midsize in the 3" opening in the door pods, to see how that sounds. Will also measure / compare using my poor man's RTA / spectrum analyser (ipad based app with Dayton Audio iMM-6 mike). My guess is the 2-way will sound better by itself but you never know...

Spyder_Man

It never hurts to experiment a little. I'm saving up my spare change to go the option D route, but there is a reason why I put five $ there.

M. Schneider

Hey bcameron -
Caution: Many 12V automotive head unit/radio's are adverse to simultaneous operation of its spkr. amplification output and pre-out level output.

Kaboom .....

bcameron59

Hmmm, hadn't considered that possibility, but does make sense as presumably there will be a resistance drop in the circuit(s) engaged. If BOTH are engaged I guess this could fry the pre-amp depending on how sensitive it is to the reduced resistance.

Since I have no appetite to test this on my porsche/becker head unit, I guess the midsize speeks are off the plate. Unless someone with a becker unit would like to test this out for me.

To quote Dr. Venkman:

"Right. That's bad. Okay. All right. Important safety tip. Thanks, Egon."

Thanks Mike!