Crossover help?


Hi to all I'm hoping someone might be able to help.

I've tried to upgrade components within my crossover and now have no HF signal.

The tweeter checks out.

I've searched for bad joints , shorts etc but can find nothing obvious.

Today I've pulled the upgraded components from the Hf circuit but still have nothing.

Using a continuity test its all good up to the main cap and after back to the terminal.

I do get a bleep from both terminals so assume thats the parallel resistor.

I'm at a loss as to why its gone completely dead.

Anyone got ideas how to check the network front to back with only a basic multimeter?

 

Thanks in advance if someone has some ideas

Regards Ian

 

notdeadyet

I used a sucker and wick, the tracks are pretty robust.

I get a a bleep up to and away from the cap, can't test the cap but neither new or old refitted made any difference.

I'll play around again tomorrow see if I can find a break.

Really struggling with this one.

Any idea what reading I should get from the coil?

Its showing 0.9 .71mm

Did you read that thread I mentioned, I find it hard to believe your tweeter not fried or board damaged. You have to make sure you haven't damaged voice coils, pretty fragile. Multimeter readings often of no use when everything in circuit. You have to put battery across speaker terminals, or send signal directly to tweeter bypass entire crossover, remove all crossover wires from tweeter terminals and test. If tweeter working, circuit board bad. Unless fried inductor.

 

You may have to find local tech or send board back to PMC. Too difficult to troubleshoot by forum. I just have to believe you've fried something.

A little late perhaps but here is how you do it.

Notice the last few pictures are the crossover upgrade. The last one is annotated with measured values and the wires that attach. There are also pictures of the original xo that I didn't post but are the same, multiple pictures including one annotated with all values and connections. Also in addition to this the parts were physically labeled, both the wires inside the speaker and on the boards. All the wiring is point to point and every part on the original was measured individually. This is how you do it when you want everything to work right the first time. 

If you take real clear pictures from different angles showing clearly all the solder joints we might still be able to figure this out. That is your best bet, because no manufacturer is going to do anything but sell you another crossover, and probably not even that. If you were making speakers and a customer called saying he screwed it up would you trust him to not screw up installing the replacement? I wouldn't. So figure it out and fix it.

If there is a circuit board then clear pictures of both sides. Circuit board traces are pretty thin, it is real easy to burn one out if you're not skilled at soldering. 

These are the photo OP posted on his system page, Seems like a simple two ways 2nd order xover with total 6 components.

The 3rd photo I believe is the original xover.

Based on the picture, I draw out the schematic:

  1. Without tweeter connect to the board, use ohm meter test across the HF input terminals, it should be Infinite resistance.
  2. Across the output terminals to tweeter, it should has a reading of about 3ohm or little higher ( 2.7ohm+DCR of the small inductor).
  3. Ohm meter on HF negative input terminal to negative tweeter output terminal should has 0ohm reading.

Hope it helps and good luck 🤞

 

Thanks imhififan thats exactly what I was hoping someone could come up with.

Just checked the network as you suggested.

HF input terms OL

HF output terms starts at 0 climbs to 3.1

HF - to HF - 0.00

Surely its not possible the 3.3 cap stops that particular tweeter from functioning?

The new tweeters have just arrived but I can play with them until later this evening