I know this has been discussed to death but I still have a sibilance problem.Recently I attenuated the tweeters with a variable resistor.This helped and made listening much better but I just can not tame that ssss.I thought it was the tweeter at first but if I completly turn the tweeter off with the variable resistor I can still here it coming through the midrange driver.Ok my receiver is not the best but a 400.00 Sony.I do not think it is the Sony as I have had the same speakers and others (telydyne acoustic research AR9's,polks and klhs) powered by the Sony with no problem.I also have a integrated amp and hooked up to it I have the same problem.The speakers I have the worse sibilance on are the ones I currently use which I used a pair of Fisher cabs and removed all drivers and crossovers and replaced with others.i have visited this forum for about a month now and most of the things everyone talks about I understand some... but most is way over my head.I listen to a lot of music through the directv music channels.I want to think it is a compression thing on directv as I get the same sibilance when just listening to tv without using the receiver.But when I listen to FM the siblance is there also(not as bad though)and also on some cd"s.It is wierd because certian programs or songs there is no sibilance and others it is terrible.The sound of these speakers are beautiful...except when the sibilance comes into play.What am I missing here???I have put a lot of time in these speakers and have been struggling with this forever.I have now 5 different sets of tweeters that I have changed and the same results.And as I said the sibilance is also coming through on the mid.I have changed the wiring from the crossovers to the speakers with cooper and then to silver then to the original and still the same.Is there a voodoo trick?Any ideas.Thanks...
Hi Mate
It sounds like you have a cone breakup/resonance problem in your mid driver, rather than a problem with your tweeter. If you can do some basic FR measurements to find the problem frequency, then it is relatively easy just to knock up a bandpass filter to kill the troublesome peaks. Or if your drivers will cope with it, you could try lowering the crossover frequency and see if that helps.
It sounds like you have a cone breakup/resonance problem in your mid driver, rather than a problem with your tweeter. If you can do some basic FR measurements to find the problem frequency, then it is relatively easy just to knock up a bandpass filter to kill the troublesome peaks. Or if your drivers will cope with it, you could try lowering the crossover frequency and see if that helps.
I think your amplifier oscillates a bit
You say its with all your speakers so check the output filter of the amp.... If the speaker impedance is getting too low (maybe due to a strange crossover config?) this can happen...
try another amp to compare?, and measure the freq/impedance of your speakers?
You say its with all your speakers so check the output filter of the amp.... If the speaker impedance is getting too low (maybe due to a strange crossover config?) this can happen...
try another amp to compare?, and measure the freq/impedance of your speakers?
whats the part number of your Pioneer midrange ?
Is it this one ?
http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=280-020
sreten.
Is it this one ?
http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=280-020
sreten.I have 2 suggestions for you :
1) Coat the center of the midrange cone (dustcap) with some varnish/clear nail polish.
2) Add a 22 ohm (as a starting value) directly across the midrange's +/- terminals. Experiment with the resistance.
I have found these 2 to work effectively to dampen cone breakup on my Audax Kevlar 6.5" driver. Say goodbye to sibilance
1) Coat the center of the midrange cone (dustcap) with some varnish/clear nail polish.
2) Add a 22 ohm (as a starting value) directly across the midrange's +/- terminals. Experiment with the resistance.
I have found these 2 to work effectively to dampen cone breakup on my Audax Kevlar 6.5" driver. Say goodbye to sibilance
I still think the impedance of the filter is getting too low.....
because sibilance sounds through mid and tweeter as well sounds like oscillation..... and the other amp couldn't handle it too...
Is there a wrong impedance-correction network? do you have a link to the filter and speakers? The impedance measurement is not that difficult (youll need a sine-generator, 1kohms resistor and a true-rms meter)....,
Or try this: place a resistor of 4 ohms/10W in series with the speaker (just for a test) to make sure that the impedance is not getting too low, if the problem is still there it must be either indeed a driver problem, or a filter-problem (resonance in a coil/zobel network, wrong connection somewhere, faulty capacitor in both left and right speaker...)
If the problem is gone (with the resistor) the speaker will sound quite different (with the series resistor attached)..... and then its also a problem in the filter causing an impedance fall....
The above test is quite easy to check....
good luck!
because sibilance sounds through mid and tweeter as well sounds like oscillation..... and the other amp couldn't handle it too...
Is there a wrong impedance-correction network? do you have a link to the filter and speakers? The impedance measurement is not that difficult (youll need a sine-generator, 1kohms resistor and a true-rms meter)....,
Or try this: place a resistor of 4 ohms/10W in series with the speaker (just for a test) to make sure that the impedance is not getting too low, if the problem is still there it must be either indeed a driver problem, or a filter-problem (resonance in a coil/zobel network, wrong connection somewhere, faulty capacitor in both left and right speaker...)
If the problem is gone (with the resistor) the speaker will sound quite different (with the series resistor attached)..... and then its also a problem in the filter causing an impedance fall....
The above test is quite easy to check....
good luck!
make sure you have a constant 1.00V RMS sinewave.
Series the 1kohms resistor with the speaker and measure in milivolts (ac rms) across the speakers' + and -. Each milivolt corresponds to 1 ohm. Sweep with the sine and look for low points, and if you like: write things also down (for instance 20 points per decade...) draw a nice graphic
good luck!
Series the 1kohms resistor with the speaker and measure in milivolts (ac rms) across the speakers' + and -. Each milivolt corresponds to 1 ohm. Sweep with the sine and look for low points, and if you like: write things also down (for instance 20 points per decade...) draw a nice graphic
good luck!
Also I emailed the manufacture of the crossovers and this is there reply:Our 3 way xovers does cross over at 800hz and 5khz. Which means the woofer
would run for 0hz to 800hz, the mid would run from 800hz to however high it
can go and the tweeter would run from 5khz to however high it can go. Our
xovers don't cut the mid out at the high range.
Is the last sentance of this important "Our crossovers don't cut the mid out at high range" ?
would run for 0hz to 800hz, the mid would run from 800hz to however high it
can go and the tweeter would run from 5khz to however high it can go. Our
xovers don't cut the mid out at the high range.
Is the last sentance of this important "Our crossovers don't cut the mid out at high range" ?
opus007 said:
Yes it is, you can try a series first order crossover between the
mid and treble with the two components for the 12dB 5k c/o.
Connect the inductor in parallel with the tweeter (and its resistor).
Connect the capacitor in parallel with the midrange unit.
Connect these two in series and then wire up to the mid ouput.
sreten.
The shop I bought the mids at no longer sell the mids or has the specs on them . I have searched for days on the web looking for specs but can find nothing that even mentions theses mids.The only thing on them is the numbers...
FW12ER14-51
8 ohm
Taiwan R.O.C
PT-5879D03
No where on it does it say Pioneer.The contact posts look to be gold.I would post a picture but last time I tried that the picture did not follow my post.
FW12ER14-51
8 ohm
Taiwan R.O.C
PT-5879D03
No where on it does it say Pioneer.The contact posts look to be gold.I would post a picture but last time I tried that the picture did not follow my post.
First let me say thanks to all of of the group. I am learning a ton from reading the forum for the last year. This is my first real post.
I am not at my wits end by the sibilance but I hoped to reduce it in my sysytem. From reading the posts on sibilance it appears that this mid frequency emphasis might be caused by several things. I hoped the group might have some opinions on the more likely culprit before I start at random.
Tubes? Coupling caps? Diodes, crossover caps? Speaker drivers, crossover caps?
I was planning a few mods but I thought I would ask before I go too far or in the wrong direction. I have a Chinese "Gold-ox" 300B amp with stock Chinese tubes. I am planning to change the 4 x 300b tubes but this is some hefty spending cash for sure. The pair of critical internal coupling capacitors between the drivers look like they are a slightly special but are certainly small and look poorly constructed and labeled. I was considering replacing the tubes anyhow and considering replaing the caps with some Musicaps, Auricaps (?) something better. The power supply diodes and caps I think are standard junk but it will be some work to get at them due to the amplifiers construction. This is why I thought I would ask first.
The speakers are JMLabs Cobalt 815 MTM towers - stock. I was considering upgrading the caps in the crossover (value for value)as well but I have no sound measurement capability for tweaking the crossover points. I can try adding some resistors across the midrange as suggested but I am reluctant to add coating to the dustcaps just yet. I can unsolder but I am not so sure about the removing the coating without dissolving any construction materials on the speaker cones.
The preamp is an Acurus PS1 (SS) class A. - stock.
The CD player is a stock Marantz 67se and a DIY outboard DAC using the CS4398 eval board and the Lundahl transformer coupling. (no opamps). I experience the sibilance with and without the DAC but the system definitely sounds better overall with the DAC and the sibilance is more tolerable.
The speaker cables are Tara labs Temporal Continuum and the interconnects are some MIT. I have also tried the DIY Venhaus silver, liked them but gave them away and not yet replaced them.
Lastly the room is a bit live with hardwood floors and textured drywall with only a thin carpet but it is not wall to wall. It could be the room as well. Any opinions would be sincerely appreciated. Thank you.
Adam12
I am not at my wits end by the sibilance but I hoped to reduce it in my sysytem. From reading the posts on sibilance it appears that this mid frequency emphasis might be caused by several things. I hoped the group might have some opinions on the more likely culprit before I start at random.
Tubes? Coupling caps? Diodes, crossover caps? Speaker drivers, crossover caps?
I was planning a few mods but I thought I would ask before I go too far or in the wrong direction. I have a Chinese "Gold-ox" 300B amp with stock Chinese tubes. I am planning to change the 4 x 300b tubes but this is some hefty spending cash for sure. The pair of critical internal coupling capacitors between the drivers look like they are a slightly special but are certainly small and look poorly constructed and labeled. I was considering replacing the tubes anyhow and considering replaing the caps with some Musicaps, Auricaps (?) something better. The power supply diodes and caps I think are standard junk but it will be some work to get at them due to the amplifiers construction. This is why I thought I would ask first.
The speakers are JMLabs Cobalt 815 MTM towers - stock. I was considering upgrading the caps in the crossover (value for value)as well but I have no sound measurement capability for tweaking the crossover points. I can try adding some resistors across the midrange as suggested but I am reluctant to add coating to the dustcaps just yet. I can unsolder but I am not so sure about the removing the coating without dissolving any construction materials on the speaker cones.
The preamp is an Acurus PS1 (SS) class A. - stock.
The CD player is a stock Marantz 67se and a DIY outboard DAC using the CS4398 eval board and the Lundahl transformer coupling. (no opamps). I experience the sibilance with and without the DAC but the system definitely sounds better overall with the DAC and the sibilance is more tolerable.
The speaker cables are Tara labs Temporal Continuum and the interconnects are some MIT. I have also tried the DIY Venhaus silver, liked them but gave them away and not yet replaced them.
Lastly the room is a bit live with hardwood floors and textured drywall with only a thin carpet but it is not wall to wall. It could be the room as well. Any opinions would be sincerely appreciated. Thank you.
Adam12
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