Help me fix my broken Revel C12!

[valerianf]

The tweeter low frequency cut is too high.
Try to do draw a schematic of the tweeter crossover and from there it will be possible to try other components values.

 

[Blumlein 88]

Thank you! Where did you get your replacements? I've been too busy to investigate this further but I'll hopefully have some time this weekend.

Not so long ago Harman had the replacement tweeters. This is like 3 years ago. So I'd try them first.

Now I still don't think it is just a tweeter issue. I think it is a crossover.

 

[cavedriver]

Thank you! Where did you get your replacements? I've been too busy to investigate this further but I'll hopefully have some time this weekend.

generally the metallized polypropylene capacitors that Parts Express sells are good place to start. Ex is Audyn or Dayton brands, but there are many others.

 

[Looneybomber]

Thank you! Where did you get your replacements? I've been too busy to investigate this further but I'll hopefully have some time this weekend.

Capacitors can be had at many different places. Parts Express, Madisound, Solen (Canada), Mouser, Digikey, etc.

Tweeters can be had by calling Revel. When I got mine, they were ~$32/ea? You can get them with/without the waveguide. You don’t need the waveguide unless you really want another
I’m not saying you need one, I’m only saying I needed to replace one, so I bought two knowing the reputation of those tweeters.

 

[napilopez]

Capacitors can be had at many different places. Parts Express, Madisound, Solen (Canada), Mouser, Digikey, etc.

Tweeters can be had by calling Revel. When I got mine, they were ~$32/ea? You can get them with/without the waveguide. You don’t need the waveguide unless you really want another
I’m not saying you need one, I’m only saying I needed to replace one, so I bought two knowing the reputation of those tweeters.

generally the metallized polypropylene capacitors that Parts Express sells are good place to start. Ex is Audyn or Dayton brands, but there are many others.

Thank you both. Was asking about the tweeters. Revel didn't respond over email but I'll give them another try. Will definitely check that nothing is wrong with crossover first, but I don't mind paying a bit to start with a fresh tweeter anyway.

 

[napilopez]

I finally got around to opening this up. Nothing seems loose, soooo bad cap it is?

 

[Sokel]

I finally got around to opening this upView attachment 366965

Better put a pic of the bottom too.

 

[napilopez]

Added!

 

[cavedriver]

nice, they actually included vibration isolators in the crossover board mounts. I don't see any problems with that crossover board.

Added!

 

[Blumlein 88]

Just off the top of my head, check coils for continuity. Next I might add a power resistor and feed it a little low level power and measure the response at the output to see if it is way off. A resistor won't be exactly the same as the tweeter, but likely close enough to show some output anomaly.

Or you could use Thevin's and Norton's theorems to troubleshoot the circuit, but if you don't already know that probably not something to learn thru forum posts.

 

[eddantes]

My $ on C4.

 

[Blumlein 88]

My $ on C4.

C4 is likely a mylar cap from the looks of it and least likely of all on the board to go bad I think. So I'm guessing you were joking based on the ratty looking hot glue.

 

[restorer-john]

Failed cap would have reduced capacitance and the tweeter would run full range, which would not exhibit the pronounced dip you see here.

Actually, it's the opposite. A cap failing loses capacitance, the Xover frequency goes up.

It could also be ferrofluid if there is some in the tweeter drying out.

The caps are just labelled by the board maker, Elytone who are IIRC just a cheap Tiawanese contract manufacturer. I'd test them all.

 

[eddantes]

C4 is likely a mylar cap from the looks of it and least likely of all on the board to go bad I think. So I'm guessing you were joking based on the ratty looking hot glue.

Eh no.... it just looks to me that it is the cap in the T+ path on the board. But - I have no idea what I'm doing, so happy to be corrected.

 

[Ze Frog]

Actually, it's the opposite. A cap failing loses capacitance, the Xover frequency goes up.

It could also be ferrofluid if there is some in the tweeter drying out.

The caps are just labelled by the board maker, Elytone who are IIRC just a cheap Tiawanese contract manufacturer. I'd test them all.

I'd go further and replace all the capacitors while the boards out, anything half decent will do.