Which resistor, if it's STILL showing a dead short or 0.00 ohms? This is the one mentioned in post 6-16 @ 12:59am
testing a crossover
hi guys and girls i have a
problem with my 3 way wilmslow-audio mirrage speakers , I am hoping you can help me with the problem,.
Lately my power amp went pop and i sent it away for repair,when i
received it back {repaired} it went pop again,on sending it back to
the repair technician ,he has come back to me ,and asked me to take
some ohms readings on the speakers, on testing the speakers , i run
these speakers using 2 power amps{Arcam Alpha 10s,using one for low
pass{bass} and the other for MID/HIGH,this is the amp which keeps
blowing,on the high /mid,on testing the terminal the bass{low pass}
read {left speaker]7.9 ohms ,right speaker bass 6.8ohms, But on the
left and right speakers hi/mid ,both read 0.0 ohms,{which we all know
is wrong}
BUT the strange thing is,when the blown amp was away,i only used one
power amp to run both speakers in bi wire config,and they worked
ok,all being a bit lack of bass and tightness,but still sound great.
So i stripped both speakers and checked the drivers,all 6 drivers
where good no shorts reading approx correct ohms for age,{Speakers
disconnected from x over}.can any one help with this,i would be so much in debt.
kind regards Mark
problem with my 3 way wilmslow-audio mirrage speakers , I am hoping you can help me with the problem,.
Lately my power amp went pop and i sent it away for repair,when i
received it back {repaired} it went pop again,on sending it back to
the repair technician ,he has come back to me ,and asked me to take
some ohms readings on the speakers, on testing the speakers , i run
these speakers using 2 power amps{Arcam Alpha 10s,using one for low
pass{bass} and the other for MID/HIGH,this is the amp which keeps
blowing,on the high /mid,on testing the terminal the bass{low pass}
read {left speaker]7.9 ohms ,right speaker bass 6.8ohms, But on the
left and right speakers hi/mid ,both read 0.0 ohms,{which we all know
is wrong}
BUT the strange thing is,when the blown amp was away,i only used one
power amp to run both speakers in bi wire config,and they worked
ok,all being a bit lack of bass and tightness,but still sound great.
So i stripped both speakers and checked the drivers,all 6 drivers
where good no shorts reading approx correct ohms for age,{Speakers
disconnected from x over}.can any one help with this,i would be so much in debt.
kind regards Mark
- ...
- 119 posts total
CORRECTION, sorry. The last test on the mid/hi amp terminals on the crossover board; when I asked to to test and then reverse the meter leads and test again. The multimeter should be set on the "diode" test mode, not ohms. The readout should display some voltage then go to OL. When you immediately reverse the leads, the display should read -x.xxx volts, then change to +x.xxx volts before going to OL. Hope your meter has a diode test function, but it's not absolutely necessary. This test just shows that the caps are charging in both directions. I still can't explain why the system worked with one amp when the mid/high amp was in repair... This is troubling. |
You can find all the photos here https://systems.audiogon.com/ Without drivers connected, The HF measurement should equal to the DC resistance of the 0.22mH inductor. The MF measurement should equal to the DC resistance of the 2.5mH inductor + 2.2Ω. |
Hi guys, sorry for the very late reply in my/your quest to sort this out,ive done a couple of thing since, taken advice on multi meter/s, fitting fully charged battery's in the digital and analogue multi meters,both tested by using an 8ohm resistor, I use for running in component/gear, just incase, removed all wire to and from the x over and cleaned the board,and flowed every joint,so there no chance of dry joints and shorts,also i have done a continuity test from every component lead to pcb tracks,all joint good, please find results of questions asked. multi meter set to ohms- between mid pos and neg 2.7 ohms between tw pos and neg 0.002 ohms mid/high inputs OL {held on for 5 secs}nothing changes mid/high inputs {reversed} OL{held on for 5 secs}nothing changes when run with one amp,in bi-wire mode both pos are NOT connected the same goes for the neg wires,the amp has 2 sets of switched speakers terminals,i use one set for the bass and the other set for the mid/high,so the two speaker cables do not touch each other resistor showing short{5w2R2J},which i measured using continuity mode,just above IP neg,when doing an ohms test is reads 2.3ohms Diode test on mid/high -OL when reversed is flashes 2.2xx,then goes to OL every time i reverse leads it flashes something {2.2xx}not sure its voltage,it doesnt tell me that |
further to reply to imhififan1 im not sure how to test for what your asking " Without drivers connected, The HF measurement should equal to the DC resistance of the 0.22mH inductor. The MF measurement should equal to the DC resistance of the 2.5mH inductor + 2.2Ω.". Not sure what 0.22mH is and also 2.5mH inductor +2.2 ohms,i know what the inductors are but not sure on mH. Also i have found that one of the capacitors has a dead short short when tested in dioode mode,{still soldered into pcb},on both x-overs, when the rest show OL,not sure if that has a bearing on anything, just throwing it out there. Any guys sorry again for the late reply,i hope your all still speaking to me, thankyou again for all your help. Kind regards Mk ps i have posted some more pic of cap showing short and the resistor ive tested thx again MK |
- 119 posts total