Hi!
I'd like to repair the filter of my front right MA BX2. I have a 5.0 system with MA Bronze, coupled to Denon 2113. The tweeter from that BX2 speaker is inaudible for some 2 weeks. I took it out and connected it directly to speaker cable, and it sounded ok, no distorsion. So there'something else inside the speak affected, probably the filter, or maybe something else too.
There's no one in my town who whould repair the speaker, and I dont want to send it far away to a specialised audio shop.
I would rather try to repair it myself, but I've never done something similar. Can you help me? The speaker was bought in feb. 2013.
Thank you.
I'd like to repair the filter of my front right MA BX2. I have a 5.0 system with MA Bronze, coupled to Denon 2113. The tweeter from that BX2 speaker is inaudible for some 2 weeks. I took it out and connected it directly to speaker cable, and it sounded ok, no distorsion. So there'something else inside the speak affected, probably the filter, or maybe something else too.
There's no one in my town who whould repair the speaker, and I dont want to send it far away to a specialised audio shop.
I would rather try to repair it myself, but I've never done something similar. Can you help me? The speaker was bought in feb. 2013.
Thank you.
See https://www.hificollective.co.uk/blog/monitor-audio-bronze-bx2-speaker-upgrade.html for the BX2 filter's electrical schematic.
It sounds like you've got a poor / failed connection or solder joint somewhere; since only the HF driver is affected you don't need to worry about the bass leg, so look to the connections in the high pass & see if any are either broken, have a failed solder joint or similar. If they have, replace or re-solder as required. While you're at it, check the resistor hasn't burned out; if it has [unlikely], replace. Since Monitor Audio used film caps & an air core inductor in the high pass filter, they're very unlikely to have failed, so unless you want to spend money, leave them alone.
It sounds like you've got a poor / failed connection or solder joint somewhere; since only the HF driver is affected you don't need to worry about the bass leg, so look to the connections in the high pass & see if any are either broken, have a failed solder joint or similar. If they have, replace or re-solder as required. While you're at it, check the resistor hasn't burned out; if it has [unlikely], replace. Since Monitor Audio used film caps & an air core inductor in the high pass filter, they're very unlikely to have failed, so unless you want to spend money, leave them alone.
Thank you. I was aware of that link, read most of it, only that my speaker has a different type/size of panel on the back. It's possible inside it's the same though, or similar. I will proceed as instructed, I hope I'll make it.
Do I have to take out the woofer in order to have access to those components? If so, apparently the driver it's also hold into place by a prong from the back, which, as I read, if i don't put it back in exact same positioning and/or tightness it may affect the sound of the speaker.
Or it's enough to take out the panel on the back, by unscrewing the 4 screws, to get to check/repair the pieces you mentioned?
Do I have to take out the woofer in order to have access to those components? If so, apparently the driver it's also hold into place by a prong from the back, which, as I read, if i don't put it back in exact same positioning and/or tightness it may affect the sound of the speaker.
Or it's enough to take out the panel on the back, by unscrewing the 4 screws, to get to check/repair the pieces you mentioned?
I've no idea I'm afraid -every speaker is different & I don't know the physical construction details of the BX2 -the advice above largely stands whatever the speaker, with the possible exception of elderly types with dried out electrolytic capacitions, which are worth replacing. That shouldn't apply to your speakers though. As far as a rear driver brace goes though -yes, you'll want to ensure it's a reasonably tight fit to the rear of the driver when it's remounted, but no so tight it warps the basket -which since it's already in place shouldn't be an issue. That aside, since they're not working anyway, the potential for a [at best very] minor difference in sound 'is as naught to having naught'. 😉
I took out the back panel and the wires connecting to it inside seem ok. But I also saw that I cant have access to the components you indicated from that back hole, so only from the front hole, behind the woofer. I clearly saw that prong starting from back of the speaker attaching to back of the woofer.
The problem is though, I dont think I'll be able to see/do anything to those components while they are attached inside, as my hand will cover the view once i push through it. Looks like I'll (of course) have to take out the panel to which the said components are attached.
For now I'll refrain from doing that. At least the woofer is working all right, and I guess I can live without the higher frequencies of the front right BX2 - the other front tweeter will compensate (plus the right woofer itself should help a bit), plus the tweeters from the other 3 speakers...
I will think about it.
The problem is though, I dont think I'll be able to see/do anything to those components while they are attached inside, as my hand will cover the view once i push through it. Looks like I'll (of course) have to take out the panel to which the said components are attached.
For now I'll refrain from doing that. At least the woofer is working all right, and I guess I can live without the higher frequencies of the front right BX2 - the other front tweeter will compensate (plus the right woofer itself should help a bit), plus the tweeters from the other 3 speakers...
I will think about it.
Do you have a simple multimeter to measure DC resistance, a smartphone to take flash pictures, and are the hi-lo separate binding posts connected by jumpers?
Disconnect hi from lo then measure across hi +/- posts and post + to speaker + lead, post - to speaker - lead, then + to each crossover component leads, etc. until you find a break in the circuit -- likely near a binding post.
Disconnect hi from lo then measure across hi +/- posts and post + to speaker + lead, post - to speaker - lead, then + to each crossover component leads, etc. until you find a break in the circuit -- likely near a binding post.
That's a good idea, thank you. I don't have a multimeter, but I'll probably either buy or borrow one. You mean the binding posts from behind the speaker's back panel? Yes, they are connected by jumpers to wires, inside the cabinet. I did take a picture of them but I couldnt see much inside the speaker, other than the rod connecting the back of speaker to the back of woofer. I didnt see any other electrical components. Most probably from the front of the speaker, if I take out the woofer, it will be another picture of what's inside.
To have an idea how noob I am in this domain, I dont know how a driver looks like, nor a filter or a crossover. As about capacitors, resistors/transistors or other electronic (basic) components, I am also very much foggy, so to speak, about their appearence. I (think) I can easily borrow a soldering device, if needed. Or buy other components and replace the damaged ones - but would they fit? Of course, a friend or neighbour electronist/electrician would solve everything quickly, but the two guys I know are not trustworthy.
To have an idea how noob I am in this domain, I dont know how a driver looks like, nor a filter or a crossover. As about capacitors, resistors/transistors or other electronic (basic) components, I am also very much foggy, so to speak, about their appearence. I (think) I can easily borrow a soldering device, if needed. Or buy other components and replace the damaged ones - but would they fit? Of course, a friend or neighbour electronist/electrician would solve everything quickly, but the two guys I know are not trustworthy.
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