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
likklegerry
The formula for parallel resistance is 1/Rt= 1/R1+1/R2+1/R3....   
https://www.electronics-notes.com/articles/basic_concepts/resistance/resistors-in-series-parallel.ph...

Since he measured almost 8 ohms then the total resistance will be 1/8 ohm + 0 ohm or 0.125ohm.  

I think we all can agree that is a pretty low resistance and would suck the bass and dynamics out of most amps. 

What I don't understand is where is the short? And how does the driver manage to still get enough signal to make sound even though there is a dead short?
Got me MC. I think the repair guy missed something.. If it was to heavy a load it will pop a fuse not blow up. Must have one sorry protection circuit.

TWICE. I don’t think so.. It’s the amp or PC or RCA or something exclusive to THAT amp..

The input to the amp?

It should pop a fuse if it’s on the output side, like a speaker issues, usually.

All I know is neg to neg and pos to pos = 1/2 the two numbers added together. 8 ohm top + 6 ohm bottom = 14 ohms /2 = 7 ohms

Running neg to pos, to neg to pos, combines the two. 6 ohm bottom + 8 ohm top = 14 ohms.

8 -14 ohms loads on my valve amps are just perfect. They run a LOT cooler and clear as a bell all the way to 100% volume..

I’m likin’ the bass at 8-12 ohms better too, with BIG class d amps. They are 12K amps. 1700 x 2 all day long at 12 ohms bullet proof. Dirt cheap!

Get a Behringer NU12000 (NO DSP) move your other amp to the top. Be happy for 400.00 and 10 years.. I disconnect two of the 3 fans and put the last one on a switch. Perfect.. DEAD quiet.. or hook it to 10-12 18" subs.. It will push EVERY one to 120 db.

I'm thinkin' 4 new 21" Dayton's with 8 18" passives would be a good bass system .. :-) I like a room that can tenderize meat in a pinch.. :-)
    Wilmslow Audio built some fairly complex crossovers, for some of their systems, though I’m not familiar with the Mirage’s.                                                                                   A DMM can easily read impedances, through the inductors in a woofer’s series circuitry.     The capacitors in mid/tweet series circuits are another story.                              I could (easily) be wrong, but: I’d put my money on the speakers/crossovers being OK and something in the amp, or cables/connections: the culprit.
I have a love/hate relationship with puzzles like this. On the one hand I love em because it is nice to think they can be solved if only you know enough. On the other hand I hate em because you never can be sure you are getting the whole story. Like, one train leaves at 30mph, another at 40, how many painters does it take to earn $40?  

In this case I can't help wondering, how on Earth did two speakers go bad at the same time? In other words maybe zero ohms is a red herring. No trains left the station. Three buckets of paint, and the waitress earned a $40 tip?
The formula for parallel resistance is 1/Rt= 1/R1+1/R2+1/R3....  
https://www.electronics-notes.com/articles/basic_concepts/resistance/resistors-in-series-parallel.ph...

Since he measured almost 8 ohms then the total resistance will be 1/8 ohm + 0 ohm or 0.125ohm.  
If any one or more of the paralleled resistor is 0 ohm, it is a short circuit and the total resistance should be 0 ohm.