Help with external subwoofer crossover.

[kininigin]

Hi all,

Having after recently rearranging my system, I developed a horrible hum from my main speakers. After unplugging and plugging various items I narrowed the cause to my subwoofer control unit. I have opened it up and it has a partially burned circuit board.

I would like to get this repaired if possible (really missing the duel subs) Does anyone know of someone who would be able to carry out this work or at least say if it is salvageable?

In case it’s not repairable, can anyone suggest an alternative option?

Thanks :)

[fatmarley]

I was going to suggest BK Electronics sub plate amps but it's a servo corrected subwoofer, so I think the only option would be repair. Maybe contact Paradigm for advice?

[kininigin]

The amps for the subs are fine, it's the external cross over which is knackered! I did contact Paradigm but all they said was contact your local dealer. I was hoping someone on here could recommend someone to look at it, or suggest an alternative external analogue subwoofer crossover.

[fatmarley]

Oh I see.

Do you know if it has SMD components or through hole? If it uses through hole then Arkless electronics may be able to help. I don't think he touches anything with SMD.

[drrdf]

Understandably. SMD pcbs are a nightmare to repair. They may be less expensive to manufacture in the first place, but can be almost impossible to repair. The tracks tend to come off the pcb when de-soldering components.

[kininigin]

Oh I see.

Do you know if it has SMD components or through hole? If it uses through hole then Arkless electronics may be able to help. I don't think he touches anything with SMD.

I don’t think so, looks like through hole resisters but I’m no expert in these things.

I’ve been given a number for someone who may be able to help, if that doesn’t work out, I’ll try Arkless and Jez is it? Been awhile since being on here.

[kininigin]

In case it cannot be repaired, can anyone suggest an alternative option?

It would need to be analogue, have high pass output at 50Hz 80Hz and 120Hz, 2 subwoofer outputs with phase control on at least 1 of the outputs, have a subwoofer cutoff frequency ranging from 35Hz and 150Hz and be of decent quality

[kininigin]

Bit of an update. I've not been able to get this unit repaired which I'm a bit gutted about. I've looked at minidsp but don't really want my turntable going through that.

Having trouble finding something which is suitable. The search continues.

[Mr.Ian]

Struggle to believe these cant be fixed, whats the obstacle? The x30 is easy to post but 24v ac psu might need to be sent too
. Fall back option might be pro audio, cheap behringer crossoverd are used by several on av scene. Another option is to have some one build you a crossover or add a low pass filter to a second output on amp, harrison mod inline filters for example. Have you asked alan "firebottle" on here

[kininigin]

Struggle to believe these cant be fixed, whats the obstacle? The x30 is easy to post but 24v ac psu might need to be sent too
. Fall back option might be pro audio, cheap behringer crossoverd are used by several on av scene. Another option is to have some one build you a crossover or add a low pass filter to a second output on amp, harrison mod inline filters for example. Have you asked alan "firebottle" on here

Well the guy who was trying to sort it said he couldn't get a schematic for it so was unable to do anything with it. Not sure if you need a schematic to fix it. I haven't asked anyone else as of yet but will give Alan a shout when i get it back. Will look at the Behringer option. Wouldn't know where to look to get one built. what sort of cost would i expect for that? Had a quick look at the inline filters, couldn't figure out how i would use them to blend sub and speakers together :scratch:

[Mr.Ian]

Thinking on about it, you are right, the servo 15 doesnt have any controls on the sub so you need to control volume, crossover and possibly phase too externally. This is probably a step too far for any route based round inline fliters and/or a second output from the preamp.

Maybe an old legacy av processor as a preamp. Proceed, Classe, Krell made some that were pretty decent music wise, dont know if the subs worked on 2 channel though. Or you could sell the servo 15 on an AV forum and buy something with built in controls

But personally I would not give up on repair yet. I am pretty sure Alan will be able to sort it, he has fixed in a matter of minutes things that other "engineers" have told me they cannot repair.

My gut feeling is saying it cant be fixed without a circuit diagram might be more to do with how attractive the repair is and what the agent feels they can charge for the work. Sure it is easier when all the parts/values are specified but I dont see this being a reason for non repair.

[kininigin]

I really would prefer to get the unit fixed. It worked very well with my speaker system, which has been designed to work together. Definitely not getting rid of the subs. Took me ages to get 1 never mind 2.

The av processor is a good shout but not for me. Had a look at the Behringer stuff, could be a possibility for a short term fix. Need to look into them a bit more. Would mean buying new cables though to hook everything up!

I will contact Alan and see what he thinks. Will try and post some pics of the issue if i can.

[kininigin]

Here is a link to a picture of the issue with the unit. Hopefully it is repairable.
(https://postimg.cc/vcDSBHt2)

[kininigin]

A big thank you to Alan (Firebottle) for fixing my subwoofer crossover unit and also a Ortofon sut I have. Can't wait to get the subs set up again. Big bad bass is back! :D