Two Anthem STR amp failures within 1 year

N

Northporter

Audiophyte
Stereo System: STR amp and STR pre-amp driving B&W 802B speakers. I really liked the sound and performance of the Anthem additions to my system. After 6 months my STR amp failed and was replaced by Anthem. The replacement failed within a year! Reasons for failure were never reported back to me. Both amps were dealer installed.
The Anthem rep convinced me to accept 2 M1 mono blocks in lieu of the STR. I would prefer an STR amp- that does not fail....
 
TLS Guy

TLS Guy

Audioholic Slumlord
Stereo System: STR amp and STR pre-amp driving B&W 802B speakers. I really liked the sound and performance of the Anthem additions to my system. After 6 months my STR amp failed and was replaced by Anthem. The replacement failed within a year! Reasons for failure were never reported back to me. Both amps were dealer installed.
The Anthem rep convinced me to accept 2 M1 mono blocks in lieu of the STR. I would prefer an STR amp- that does not fail....
We do seem to get complaints about failures of Anthem equipment here more often than I would have thought we would considering market share. However these factors are hard to judge.

The bigger issue is your speakers. Unfortunately B & W speakers, as a group, tend to present a torture test to amplifiers. I don't know why B & W persist with this, but they do. It has seemed strange to me that B & W have produced so many speakers over the years, that have such off the wall impedance curves and phase angles.

This is a graph of the phase angles and impedance plot of your speakers.



Note that the impedance is around 3 ohms during much of the range where a lot of power is required. In addition the phase angle is a whopping -65 degrees at a point where the impedance is four ohms. That is just a horrible load, and close to a short circuit effectively at that point.

Now your STR amp does have a 2 ohm rating. However I suspect the amp is just not comfortable with the load presented by those speakers.

As say this as someone who has designed many speakers over the years, and have never had a design present a load anything like as horrific as the one above, and would not pass one that did. I just would expect trouble. John Atkinson in his review of those speakers commented on the fact, that that load would stress amplifiers, and so it will.

So having blown two of those amps, if you keep replacing them, you will keep blowing them driving those speakers.

It has often been commented that to drive many B & W speakers, you need an amp that can substitute as an arc welder!
 
Verdinut

Verdinut

Audioholic Ninja
Should you want a stereo power amp that will be able to handle those hard to drive B & W speakers, I have an excellent solution for you. Just get a pro audio QSC Cinema amp such as the DCA 2422 which has a clean power rating of 425 watt/ch for an 8 ohm load.

That amp, which has excellent specs, is a beast and you can't kill it. It uses a variable speed cooling fan which might be annoying, but if your listening position is 10 feet or more from the speakers, you won't hear it. I'm using four QSC DCA Series amps in my HT system and this series of amps will drive 2 ohm loads without a hitch. As a matter of fact, they are used in Cineplex theaters across North America.

Those amplifiers are only sold by theater equipment suppliers. You can get a good price on them at cinemanext.com

 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Also look at the ATI class-D amps with 7YR warranty.
 
P

PENG

Audioholic Slumlord
For someone who goes through amps like that, I would highly recommend Bryston's 28 B3 or 14B3 that comes with 20 years warranty.

Those Anthem STR amps should be great for the biggest B&W diamonds if the owners mostly listen to classical music and other acoustic Jazz music, but probably won't do too good with rocks recorded at loud level, compressed and listened to at or near reference level. That's because their 600 W into 2 Ohm kind of impressive ratings are base on 1 channel at a time. The amps were optimized for people who focus on music that has lots of high peaks but also reasonably quieter moments in between. In other words, those amps won't be able to sustain their claimed rated output continuously. That's just my take based on their website info, and photos of the transformers and storage caps.
 
highfigh

highfigh

Audioholic Overlord
At this point, I would check the speakers- a better warranty won't help anything, although a manufacturer with the stones to cover their products for 20 years would seem to be confident in their designs.
 
D

Danzilla31

Audioholic Ninja
For someone who goes through amps like that, I would highly recommend Bryston's 28 B3 or 14B3 that comes with 20 years warranty.

Those Anthem STR amps should be great for the biggest B&W diamonds if the owners mostly listen to classical music and other acoustic Jazz music, but probably won't do too good with rocks recorded at loud level, compressed and listened to at or near reference level. That's because their 600 W into 2 Ohm kind of impressive ratings are base on 1 channel at a time. The amps were optimized for people who focus on music that has lots of high peaks but also reasonably quieter moments in between. In other words, those amps won't be able to sustain their claimed rated output continuously. That's just my take based on their website info, and photos of the transformers and storage caps.
PENG gave me some help on this just recently. I too am an Anthem owner. The Anthem AVM 60 and the Anthem MCA 525. I just replaced my front 3 speakers and they present a more challenging load to the amp. Now my power requirements are large at the distance I sit. But I could tell when the amp seemed to hit its limits especially with music. I believe for the reason you mentioned above

So I'm in the same boat the need to find a beefier amp. But just like you I did enjoy my Anthem gear it sounds great to my ears. So I was reluctant. But it seems like it's unavoidable with the speakers your driving

Good luck on finding a new amp. All the options mentioned above sound great
 
D

Danzilla31

Audioholic Ninja
For someone who goes through amps like that, I would highly recommend Bryston's 28 B3 or 14B3 that comes with 20 years warranty.

Those Anthem STR amps should be great for the biggest B&W diamonds if the owners mostly listen to classical music and other acoustic Jazz music, but probably won't do too good with rocks recorded at loud level, compressed and listened to at or near reference level. That's because their 600 W into 2 Ohm kind of impressive ratings are base on 1 channel at a time. The amps were optimized for people who focus on music that has lots of high peaks but also reasonably quieter moments in between. In other words, those amps won't be able to sustain their claimed rated output continuously. That's just my take based on their website info, and photos of the transformers and storage caps.
Hey PENG he moved to there M1 monoblocks they're class D version. What's your take on those monoblocks being able to drive those speakers?
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
For someone who goes through amps like that, I would highly recommend Bryston's 28 B3 or 14B3 that comes with 20 years warranty.

Those Anthem STR amps should be great for the biggest B&W diamonds if the owners mostly listen to classical music and other acoustic Jazz music, but probably won't do too good with rocks recorded at loud level, compressed and listened to at or near reference level. That's because their 600 W into 2 Ohm kind of impressive ratings are base on 1 channel at a time. The amps were optimized for people who focus on music that has lots of high peaks but also reasonably quieter moments in between. In other words, those amps won't be able to sustain their claimed rated output continuously. That's just my take based on their website info, and photos of the transformers and storage caps.
I would get Bryston amps with 20YR warranty also if price isn't an issue. :D
 
P

PENG

Audioholic Slumlord
I would get Bryston amps with 20YR warranty also if price isn't an issue. :D
It is possible that they might have build in a little extra money to cover the potentially higher warranty cost, but I don't believe it would be a significant number, may be a % or 2:D. More than likely their costs are higher mainly because of the design that calls for better reliability and longevity, all else being equal.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
It is possible that they might have build in a little extra money to cover the potentially higher warranty cost, but I don't believe it would be a significant number, may be a % or 2:D. More than likely their costs are higher mainly because of the design that calls for better reliability and longevity, all else being equal.
Would be interesting to see reliability reports of Bryston vs ATI amps.
 
3db

3db

Audioholic Overlord
Stereo System: STR amp and STR pre-amp driving B&W 802B speakers. I really liked the sound and performance of the Anthem additions to my system. After 6 months my STR amp failed and was replaced by Anthem. The replacement failed within a year! Reasons for failure were never reported back to me. Both amps were dealer installed.
The Anthem rep convinced me to accept 2 M1 mono blocks in lieu of the STR. I would prefer an STR amp- that does not fail....
Do you have lots of airflow around your equipment for sufficient cooling?
 
highfigh

highfigh

Audioholic Overlord
We do seem to get complaints about failures of Anthem equipment here more often than I would have thought we would considering market share. However these factors are hard to judge.

The bigger issue is your speakers. Unfortunately B & W speakers, as a group, tend to present a torture test to amplifiers. I don't know why B & W persist with this, but they do. It has seemed strange to me that B & W have produced so many speakers over the years, that have such off the wall impedance curves and phase angles.

This is a graph of the phase angles and impedance plot of your speakers.



Note that the impedance is around 3 ohms during much of the range where a lot of power is required. In addition the phase angle is a whopping -65 degrees at a point where the impedance is four ohms. That is just a horrible load, and close to a short circuit effectively at that point.

Now your STR amp does have a 2 ohm rating. However I suspect the amp is just not comfortable with the load presented by those speakers.

As say this as someone who has designed many speakers over the years, and have never had a design present a load anything like as horrific as the one above, and would not pass one that did. I just would expect trouble. John Atkinson in his review of those speakers commented on the fact, that that load would stress amplifiers, and so it will.

So having blown two of those amps, if you keep replacing them, you will keep blowing them driving those speakers.

It has often been commented that to drive many B & W speakers, you need an amp that can substitute as an arc welder!
Why would a manufacturer send speakers with that load to market? If they also build an amplifier that can drive them, I could understand- they would be able to have an exclusive market for non-failing amplification until someone else decides to enter the game but these are ridiculous.

I still think the speakers, wiring an settings need to be checked.
 
highfigh

highfigh

Audioholic Overlord
Stereo System: STR amp and STR pre-amp driving B&W 802B speakers. I really liked the sound and performance of the Anthem additions to my system. After 6 months my STR amp failed and was replaced by Anthem. The replacement failed within a year! Reasons for failure were never reported back to me. Both amps were dealer installed.
The Anthem rep convinced me to accept 2 M1 mono blocks in lieu of the STR. I would prefer an STR amp- that does not fail....
Do you have a cat or dog? They like to chew on cables.
 

newsletter
  • RBHsound.com
  • BlueJeansCable.com
  • SVS Sound Subwoofers
  • Experience the Martin Logan Montis
Top