21 replies to this topic

[Ruckus]

i would pull the existing ICE wiring out and put a new set in, there could be a fault which may damage your head unit after a while. Can't beat a fresh clean install!

Also i prefer to use 4.7uF down to 2.2uF bipolar caps (the lower the value, the higher the frequency crossing...on my PA cabs i have some JBL tweeters with 1uF caps...really tingly!)

This is car audio not PA... 4OHM not 8.

A 2.2uf cap on a 4ohm load would cross it at around 20,000k which is the top end limit limit of most car headunits!!

At 8ohms a 4.7uf IS 4000hz ish. With you 1uf cap on a 8ohm driver your still crossing at 20k!? cant see why you would cross so high as 20k is the limit of human hearing, unless you running normal tweeters plus these as super tweeters, which as such make no audible sound but adds a 'feeling' to the music.

And you must remember crossing high ONLY works if you have the mid driver to 'meet' the higher end. most 2 way setups need to be cross at 2000 to 4500hz max.

[pbrain]

i would pull the existing ICE wiring out and put a new set in, there could be a fault which may damage your head unit after a while. Can't beat a fresh clean install!

Also i prefer to use 4.7uF down to 2.2uF bipolar caps (the lower the value, the higher the frequency crossing...on my PA cabs i have some JBL tweeters with 1uF caps...really tingly!)

This is car audio not PA... 4OHM not 8.

A 2.2uf cap on a 4ohm load would cross it at around 20,000k which is the top end limit limit of most car headunits!!

At 8ohms a 4.7uf IS 4000hz ish. With you 1uf cap on a 8ohm driver your still crossing at 20k!? cant see why you would cross so high as 20k is the limit of human hearing, unless you running normal tweeters plus these as super tweeters, which as such make no audible sound but adds a 'feeling' to the music.

And you must remember crossing high ONLY works if you have the mid driver to 'meet' the higher end. most 2 way setups need to be cross at 2000 to 4500hz max.

All my PA speakers are paired 8 ohm drivers wired in parallel (4 ohm), 1uF works perfectly..the 12" drivers handle mid/bass (125hz+), with separate 18"s doing sub 125hz

4.7uF caps used to be in the old 2" hi-fi paper tweeters which also produced quite a lot of midrange.

the mid/bass driver in a decent set of components will handle all the midrange, let the tweeter handle the 'tingles'. putting lower freqencies through the tweeter will shorten it's life...especially when playing with the volume up.

The 4 tweeters in my Mini have 2.2uF, i tried 3.3uF & 4.7uF...i found these too nauseating.

[Brams96]

To oli8925 or luvlygal

First question is do you actually have a head unit in the mini? If not then might be a good idea to install one first (see other threads on how to do this)

If you tried the front speakers on 2-3 HU's with no luck & the speaker worked when attached to your Viva then I would suspect the wiring.

If you have some spare wire then just run a temporary connection from a HU you know works (maybe from the Viva) straight to the front speakers, one at a time, and check you get sound. Then do the the same with the tweeters, one at a time. If you get sound from the speakers & tweeters you know you need to replace the wiring in the car. Hope this helps.

[Ruckus]

All my PA speakers are paired 8 ohm drivers wired in parallel (4 ohm), 1uF works perfectly..the 12" drivers handle mid/bass (125hz+), with separate 18"s doing sub 125hz

4.7uF caps used to be in the old 2" hi-fi paper tweeters which also produced quite a lot of midrange.

the mid/bass driver in a decent set of components will handle all the midrange, let the tweeter handle the 'tingles'. putting lower freqencies through the tweeter will shorten it's life...especially when playing with the volume up.

The 4 tweeters in my Mini have 2.2uF, i tried 3.3uF & 4.7uF...i found these too nauseating.

OK WOW… I kind of disagree with everything you just said.

Your PA setup sounds ok now you have explained the load.

But your wrong about a large mid woofer be able to correct handle the lower high frequencies. Most go to crap above around 2hkz.
Look at this plot.
http://www.europe-au...8wu-4741t00.pdf

That’s is the 7” ScanSpeak Illuminator, these are considered by some to be the best Mid Woofer out there.
The the Illuminator and its sister range Revelator where the basis of the Genesis Absolutes and the Alpine F1# speakers.
After 2k the output is all over the place, and after 7khz it drops to the floor.

If you want to run a set of tweeters cross high (5khz and up) then you will need a MID not and Mid Woofer. A 4 or 5” mid not a bloody great 7 or 8.
There is no 8 or 10” woofer in the world that can get a flat response up to 5khz.

A good tweeter will be flat down to 1000hz and yes will continue above 20khz in to the ultrasonic. But cross it at 20khz is pointless.

And I’m not talking about running a tweeter down to 800hz (although my Illuminators will happily do that.) I talking about using a tweeter in the frequencies range they are designed to work at. 2.5khz to 20khz
Tweeters usually have a Resonance frequency of between 600hz and 1.2khz, so cross over at least double that is the rule of thumb.

Please remember there is a difference between personal preference and technically correct advice.

Also why would you need 4 Tweeters in a mini? Set for the front and a set for the rear??

Edited by Ruckus, 10 May 2011 - 09:14 AM.

[oli8925]

Wow, in depth stuff I'll come back to you when I think about putting a proper system in the Viva

As for the Mini, got it sorted today. Messed about with wiring although didn't replace any so I don't exactly know why or how but it's all working again now, tweeters and speakers. Found the tweeters were already wired in with 3.3uF capacitors so didn't have to worry about that. It's all looking much better now and tidied up. When we come to really clean the car up I'll run new wires throughout, but for the time being and with the crap speakers it came with, it'll do. Thanks for the help!

[pbrain]

i would pull the existing ICE wiring out and put a new set in, there could be a fault which may damage your head unit after a while. Can't beat a fresh clean install!

Also i prefer to use 4.7uF down to 2.2uF bipolar caps (the lower the value, the higher the frequency crossing...on my PA cabs i have some JBL tweeters with 1uF caps...really tingly!)

hmmm, i'm sure is said i prefer, anyway oli8925 those 3.3uF caps will be fine, i wouldn't personally change them to 10uF (unless you have some super-duper mega tweeters). they may go louder, but i think they wouldn't last very long.

Edited by pbrain, 12 May 2011 - 07:52 AM.

[Ruckus]

i would pull the existing ICE wiring out and put a new set in, there could be a fault which may damage your head unit after a while. Can't beat a fresh clean install!

Also i prefer to use 4.7uF down to 2.2uF bipolar caps (the lower the value, the higher the frequency crossing...on my PA cabs i have some JBL tweeters with 1uF caps...really tingly!)

hmmm, i'm sure is said i prefer, anyway oli8925 those 3.3uF caps will be fine, i wouldn't personally change them to 10uF (unless you have some super-duper mega tweeters). they may go louder, but i think they wouldn't last very long.

OK point taken,

The 3.3uf will be crossing about about 10khz quite high but if they are what came with the Tweeter i'd also stick with them.