Anthem MCA50 - Capacitor Failure

C

Canuck09

Audiophyte
I recently had a capacitor let go on my Anthem MCA 50. I am located in Western Canada and before I box this 70lb amp up and send it across the country to Anthem I thought I would reach out to get some thoughts. The amp was manufactured in 2003 so it is close to 20 years old. I have been using this amp to power 4x Paradigm Signature S1's and a Paradigm Signature C1 using an Yamaha Aventage A840.

I have had some people tell me that the caps dry out and that all should be replaced, I have had some people tell me that the amp is beyond its life and is effectively garbage. I have been thinking about moving on from the Amp and simply powering my setup direct off a new receiver such as the Yamaha A6A, Anthem 540, or Onkyo TZ50. Given Genes review of the Yamaha A6A I am leaning towards the Onkyo. Whatever happened to my Anthem Amp appears to have taken out my Yamaha A840 receiver also as it won't turn on and is flashing a power supply code.

Interested in your thoughts
 
TLS Guy

TLS Guy

Seriously, I have no life.
I recently had a capacitor let go on my Anthem MCA 50. I am located in Western Canada and before I box this 70lb amp up and send it across the country to Anthem I thought I would reach out to get some thoughts. The amp was manufactured in 2003 so it is close to 20 years old. I have been using this amp to power 4x Paradigm Signature S1's and a Paradigm Signature C1 using an Yamaha Aventage A840.

I have had some people tell me that the caps dry out and that all should be replaced, I have had some people tell me that the amp is beyond its life and is effectively garbage. I have been thinking about moving on from the Amp and simply powering my setup direct off a new receiver such as the Yamaha A6A, Anthem 540, or Onkyo TZ50. Given Genes review of the Yamaha A6A I am leaning towards the Onkyo. Whatever happened to my Anthem Amp appears to have taken out my Yamaha A840 receiver also as it won't turn on and is flashing a power supply code.

Interested in your thoughts
How to you know the problem is a capacitor, and which capacitor? If your A840 was taken out, at the same time, this sounds like a power surge or lightning strike. It would be most unlikely that a power amp failure, would take down anything connected to the inputs, but not impossible. I can tell you though that if there we enough voltage at the input of the MCA 50 to take down your receiver, then that MC 50 is toast.

Caps fail, but 2003 is not that old. Generally I only replace caps that fail, unless there are some that are known to fail.

I would avoid Onkyo personally. Going to a receiver to power your speakers, will be a downgrade.

I would try and find out what is wrong with your Anthem MCA 50.

I tried to find a service manual, but could not.
 
C

Canuck09

Audiophyte
I appreciate the feedback! Below are some pictures showing the cap that failed. I am not sure what led to its failure. It happened at about 9am while my kids watched cartoons on low volume. There were no storms or apparent power bumps. I have this amp connected to a power conditioner (Belkin), along with the receiver. Some have noted that they would be concerned with the power conditioner...I am not sure.
A3.jpg
A1.jpg
 
TLS Guy

TLS Guy

Seriously, I have no life.
I appreciate the feedback! Below are some pictures showing the cap that failed. I am not sure what led to its failure. It happened at about 9am while my kids watched cartoons on low volume. There were no storms or apparent power bumps. I have this amp connected to a power conditioner (Belkin), along with the receiver. Some have noted that they would be concerned with the power conditioner...I am not sure.
View attachment 53381View attachment 53382
That looks like a robust power supply. I would be 99.99% certain that cap had catastrophic failure due to severe over voltage. I would bet your receiver was taken out by the same overvoltage.

I suspect the Belkin power conditioner is toast. You should NEVER connect a power amp to a power conditioner, only the low power devices, like preamps, processors, computers etc.

My strong suspicion is that, both your MCA 50 and your receiver are toast and beyond repair unfortunately. Caps have to be much older than yours before they fail catastrophically like that, even then it is unusual.

I hope your speakers are OK. You had better check them carefully before connecting them to anything else.
 
C

Canuck09

Audiophyte
Do you suspect it was sever over voltage from the power to the power conditioner? Or something to do with the power conditioner itself? How would you go about checking if my speakers are okay?

Thanks!
 
TLS Guy

TLS Guy

Seriously, I have no life.
Do you suspect it was sever over voltage from the power to the power conditioner? Or something to do with the power conditioner itself? How would you go about checking if my speakers are okay?

Thanks!
There is no way I can answer that question. As nothing else in the house has been hit, and you noticed nothing unusual, I suspect the Belkin unit as the most likely culprit, but I can be far from certain of that. I have a high degree of certainty that both receiver and power amp were taken out by over voltage. I would get rid of the Belkin as either it was the cause, or was subjected to over voltage and now suspect on that account alone.

You can test the speakers by checking the DC resistance of each against spec for a start. The make sure all drivers are working by testing them under low power and gradually advancing the power.

Unfortunately this has been a costly catastrophe for you.

By the way, I did do a search to see if the Anthem MC 50 is prone to power cap failure, and I can find no evidence that they are.

If just the MC 50 had failed, I would put it down to a one off defective cap. But with the Yamaha taken out, I would be pretty certain of an external cause, especially as your blinking light on light on the Yamaha suggests power supply failure. That all adds up to an over voltage hit to me.
 
C

Canuck09

Audiophyte
Now you have me thinking...And worrying. After the amp failed I pulled it out an re-wired my speakers back to the receiver. When I fired it up it came on normally, with video and audio, but I noticed that only the center speaker was outputting audio. Then a few minutes later the receiver shut off. I restarted it and it shut off again and went into protection mode. I wonder if my speakers were fried and I ended up frying my receiver with them... My TV, cable box, and wifi router are all connected through this Belkin and they seem to be working okay. I really hope my Paradigm speakers are not toast.

Again, I really appreciate your feedback here...
 
TLS Guy

TLS Guy

Seriously, I have no life.
Now you have me thinking...And worrying. After the amp failed I pulled it out an re-wired my speakers back to the receiver. When I fired it up it came on normally, with video and audio, but I noticed that only the center speaker was outputting audio. Then a few minutes later the receiver shut off. I restarted it and it shut off again and went into protection mode. I wonder if my speakers were fried and I ended up frying my receiver with them... My TV, cable box, and wifi router are all connected through this Belkin and they seem to be working okay. I really hope my Paradigm speakers are not toast.

Again, I really appreciate your feedback here...
Well, it is hard to know what is the chicken or the egg with that one.

It could be that the receiver was damaged and it took awhile for it to go into permanent protection. On the other hand the speakers could have been damaged by the power amp, and then taken down the receiver.

However, you can resolve this easily by testing the speakers carefully, one at a time.
 
mono-bloc

mono-bloc

Full Audioholic
A couple of quick questions
What happens if you disconnect the power conditioner and connect the A840 into your power supply.
Do the same with the Anthem.
Most of these so-called power conditioners are rubbish, and won't protect anything. In the event of a lighting strike or power surge the chances are it will jump right over the so-called protection circuits and fry everything it comes into contact with. If that's the case there should be signs of burn on the receiver circuit boards.

As for your speakers, Remove the speaker from the cabinet and using a double AA battery across the terminals, it should energize the speaker coil, and the speaker baffle should retract and click.. You only need to touch the terminals with the double AA for a few seconds.
 
C

Canuck09

Audiophyte
I tried connecting the A840 directly into the wall. It still only turns on if I press the 3 buttons + power to sidestep the shutoff.

I tested each speaker with a AA battery, however, I did not open the speakers up. I tested them straight from the terminals on the back of the speaker. I hope that is okay. Each speaker made a click/scratch sound when I connected them to the battery for a quick second. There really wasn't much visible movement.
 
mono-bloc

mono-bloc

Full Audioholic
The reason I said to remove the drivers from the cabinet was to insure each and every speaker was reacting to the AA battery It's just about impossible to hear each speaker while your also using the battery on the speaker terminals.
You say the A840 shuts down after a few seconds. Does it still shut down if you disconnect all the speaker cables and any incoming cables Same thing with the Anthem. Did you find any sign of burning on the circuit boards
I'm sorry I keep asking simple questions, but some time the answers to the problems are just as simple. I while ago a friend had the same problem, Complete shut down. It turn out his 3 year old was switching of the power point. And then switching it on again. smart kid, choke choke :)
 
P

PENG

Audioholic Slumlord
I appreciate the feedback! Below are some pictures showing the cap that failed. I am not sure what led to its failure. It happened at about 9am while my kids watched cartoons on low volume. There were no storms or apparent power bumps. I have this amp connected to a power conditioner (Belkin), along with the receiver. Some have noted that they would be concerned with the power conditioner...I am not sure.
View attachment 53381View attachment 53382
Is it really a MCA 50 or it is a typo, and did you buy it new? I have a MCA20 that is the two channel version so when I saw the picture of the burnt caps I found it strange that they don't look like those in the MCA amps.

Those amps were supposed to have 16,400 uf per channel so for the MCA 50, I would expect to see 10 X 8,200 uF 100 V 85 deg C caps. Anthem_Catalog_4.0:Layout 1 (anthemav.com)

You can see them clearly in the following video and yours look to have 10 X 15,000 uf caps.

Stereo Design Anthem MCA 50 Five Channel Amplifier in HD - Bing video

1643375439108.png
 
C

Canuck09

Audiophyte
It's funny you say that, I looked at the same video preview picture you have noted above and wondered why those caps are 100V and mine are 80V...But in the anthem catalogue you have attached a link to it shows the caps as 80V at 10,000 UF. Mine are 80V at 15,000 UF.

My amp is (was) definitely an MCA-50 as you can see it printed on the circuit board on the picture above. I bought it used about 6-7 years ago and it has worked flawlessly since.
 
C

Canuck09

Audiophyte
I have reached out to Anthem regarding the caps as per above. I will let you know what I hear.

Regarding the receiver, I have plugged it in directly to the wall with no other connections such as speakers etc. and It still won't turn on until I press the three buttons to bypass the shutdown. Even then it is just in what looks to be diagnostic mode.
 
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P

PENG

Audioholic Slumlord
It's funny you say that, I looked at the same video preview picture you have noted above and wondered why those caps are 100V and mine are 80V...But in the anthem catalogue you have attached a link to it shows the caps as 80V at 10,000 UF. Mine are 80V at 15,000 UF.

My amp is (was) definitely an MCA-50 as you can see it printed on the circuit board on the picture above. I bought it used about 6-7 years ago and it has worked flawlessly since.
I can see 10,000 uf if they are 80 V rated because it would be about the same as 8,200 uf 100 V if the rail voltage was increased accordingly for the 100 V rated caps. The catalogue you referred to show 80 V 10,000 uf but they might have just used an old pictures from the MCA 5 that apparently do have 10 pieces of the 80 V 10,000 uf caps. That kind of things could happen so don't be surprised.

Yours are 15,000 uf 80 V that is a much bigger gap but it may be possible that Anthem downsized the power supply on the newer version of the MCA amps. Let's see what Anthem has to say about that, if at all..

To replace those caps will be costly, and there may be other damaged parts too and in that case you would be better off getting a new amp.

I also tend to agree with TLSGuy that whatever took out the amp likely have done so with the AVR or vice versa.
 
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