Hi
I picked up a set of Monitor Audio R852/MD speakers and both tweeters are blown. I removed the tweeters and tested for continuity across the terminals and got nothing.
I also removed and tested for continuity across the yellow capacitor/resistor? in the crossover and got nothing.
So could anyone advise me on what I could use to replace or repair the tweeters and also the yellow capacitor.resistor.
I've included photos of the speakers, capacitor/resistor, and tweeter.
Any advice would be most gratefully received as I'm intrigued to find out how good they sound when fully working.
Thanks.
I picked up a set of Monitor Audio R852/MD speakers and both tweeters are blown. I removed the tweeters and tested for continuity across the terminals and got nothing.
I also removed and tested for continuity across the yellow capacitor/resistor? in the crossover and got nothing.
So could anyone advise me on what I could use to replace or repair the tweeters and also the yellow capacitor.resistor.
I've included photos of the speakers, capacitor/resistor, and tweeter.
Any advice would be most gratefully received as I'm intrigued to find out how good they sound when fully working.
Thanks.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Cap's should have no continuity to DC! 🙂 That's a good thing.
There's another thread here discussing possibly replacing the tweeter with a Morel, but that is a replacement for a C-CAM.
Take pics of the tweeter front and mounting plate?
Best,
E
There's another thread here discussing possibly replacing the tweeter with a Morel, but that is a replacement for a C-CAM.
Take pics of the tweeter front and mounting plate?
Best,
E
Thanks ErikSquires at least I now know the yellow component is a capacitor and it works (which is good news as I could find no info on it on the web and the people at my local Maplin here in the UK couldn't shed any light on it either).
Below are some more pictures of the tweeter. ANy sugeestions as to the best course of action for repair / replace?
Below are some more pictures of the tweeter. ANy sugeestions as to the best course of action for repair / replace?
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
You know, that motor structure looks VERY familiar.
https://www.parts-express.com/dayton-audio-rs28a-4-1-1-8-aluminum-dome-tweeter--275-130
https://www.parts-express.com/dayton-audio-rs28a-4-1-1-8-aluminum-dome-tweeter--275-130
So it's very hard to find a good replacement without proper measurements.
I mean, you could reach out to Monitor Audio or find som eone who knows anything about this driver, it IS possible ti's around in some other incarnation.
Otherwise, you'll need to replace the tweeter entirely... and that's tough without being able to analyze what's left and design the crossover. Dissi sometimes pulls out great solutions though. 🙂
Erik
I mean, you could reach out to Monitor Audio or find som eone who knows anything about this driver, it IS possible ti's around in some other incarnation.
Otherwise, you'll need to replace the tweeter entirely... and that's tough without being able to analyze what's left and design the crossover. Dissi sometimes pulls out great solutions though. 🙂
Erik
So, for cheaps, I'd try the Dayton Aluminum foil tweet I just sent you. Look at the spec sheet and see if it fits your mountint plate and cabinet.
If it does.. buy it! 🙂 Fix up the sound later. 🙂
If it does.. buy it! 🙂 Fix up the sound later. 🙂
I have a set of bastard R652s. They used to have the original R652 woofers, original value xover components (1.1mH, 2.2ohm and 3.3uF) and a Scanspeak D2010 tweeter. Cabinet is similar to the original - samve volume and tuning, but with the port on the front.
One of the woofers malfunctioned, and I got hold of a pair of R1200 wofers. Theses sound very good - I've had them for almost 25 years...
If your filter on the tweeter is similar - first order, 3.3uF cap and a resistor, look for a tweeter at 88-89 dB sensitivity and nominal impedance of 8 ohms. A low fs will help.
The tweeter Erik suggests needs a filter rework, as it is 4 ohms.
Edit -I now see it's basically the same filter, without the resistor. So, change the cap for a 6.6uF to fit the dayton tweeter. You may have to add a couple of resistors to attenuate the tweeter just a little.
Johan-Kr
One of the woofers malfunctioned, and I got hold of a pair of R1200 wofers. Theses sound very good - I've had them for almost 25 years...
If your filter on the tweeter is similar - first order, 3.3uF cap and a resistor, look for a tweeter at 88-89 dB sensitivity and nominal impedance of 8 ohms. A low fs will help.
The tweeter Erik suggests needs a filter rework, as it is 4 ohms.
Edit -I now see it's basically the same filter, without the resistor. So, change the cap for a 6.6uF to fit the dayton tweeter. You may have to add a couple of resistors to attenuate the tweeter just a little.
Johan-Kr
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Fenalaar told us what the typical 1" MA tweeter filter is:
http://www.diyaudio.com/forums/multi-way/305080-monitor-audio-r352-crossover-2.html#post5018607
My R300-MD had a second order filter on the 3/4" tweeter, 2.2R, 3.3uF and 0.3MH and a 1.6mH bass coil:
Not rocket science, and guess what, tweeters blow like crazy on all these designs! 😱
I'd fit one of these:
H1212-06 27TBFC/G
Very reliable unit.
I'm using a proper crossover these days. Built it myself. Below:
http://www.diyaudio.com/forums/multi-way/305080-monitor-audio-r352-crossover-2.html#post5018607
My R300-MD had a second order filter on the 3/4" tweeter, 2.2R, 3.3uF and 0.3MH and a 1.6mH bass coil:
Not rocket science, and guess what, tweeters blow like crazy on all these designs! 😱
I'd fit one of these:
H1212-06 27TBFC/G
Very reliable unit.
I'm using a proper crossover these days. Built it myself. Below:
Attachments
I didn't tell you what happened when one of the 652 woofers failed...
I had a cold so my hearing was ****. I watched a movie (Batman returns, I think), and cranked up a bit too loud. The glue between the voice coil former and the cone got unstuck...
The tweeter was still fine. Remember that the XO frequency is on the order of 5kHz or so...
Edit: The Seas is a good choice.
Johan-Kr
I had a cold so my hearing was ****. I watched a movie (Batman returns, I think), and cranked up a bit too loud. The glue between the voice coil former and the cone got unstuck...
The tweeter was still fine. Remember that the XO frequency is on the order of 5kHz or so...
Edit: The Seas is a good choice.
Johan-Kr
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Jamie123 replaced the ferrofluid on his old MA R852 tweeters, which can't be a bad idea: Monitor Audio R252 - Page 4
Nice polycone bass too. But, TBH, first order crossovers sound rough to me. It's a cheap approach. You won't catch Harbeth doing stuff like this.
Nice polycone bass too. But, TBH, first order crossovers sound rough to me. It's a cheap approach. You won't catch Harbeth doing stuff like this.
Attachments
If the tweeters show no continuity across the terminals, replacing the ferrofluid won't help.
The MAs ride on the midwoofer quality. It's smooth enough that they can cross over the tweeter quite high.
Johan-Kr
The MAs ride on the midwoofer quality. It's smooth enough that they can cross over the tweeter quite high.
Johan-Kr
Thanks for all the advice, Erik, Johan and Steve.
I've been in touch with Monitor Audio via emeil to see if they have anything, even a spec sheet, via email.
I checked out the Seas and they won't break the bank so that will be my second option. May well be asking for advice on building a crossover for the new speaker configuration (I hasten to add idiots guide as whilst I can solder I know nothing about electronics, though I do know what sounds good, to my ears at least.
I've been in touch with Monitor Audio via emeil to see if they have anything, even a spec sheet, via email.
I checked out the Seas and they won't break the bank so that will be my second option. May well be asking for advice on building a crossover for the new speaker configuration (I hasten to add idiots guide as whilst I can solder I know nothing about electronics, though I do know what sounds good, to my ears at least.
Did you get a solution to your tweeters as I have the same problem and also want to keep this as simple as possible.
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