D'Agostino Momentum amp melts down


The latest issue of Stereophile tests the Momentum amplifier and amp number 1 melts down during the precondition test. Atkinson is afraid to subject amp number 2 to the same test and only runs it for 1/2 as long as the standard test.

Parasound, Bryston, and others pass this test but the Momentum can't? Then they act like it's no big deal like it melted down. So, if that's the case, why perform the test?

The manufacturer response doesn't remark on the melt down. I would think Dan would be duly embarrassed but what the heck, those copper heat sinks sure look great.

Would a prospective buyer (not me) be hesitant to power an inefficient speaker to loud levels with this amp?

rhljazz
I am sorry that you interpret this as a melt down. The Momentum amplifiers normal operating temperature is 42-44c(107-111f)the temperature rise to 48c (118f) is inconsequential. The amplifier in question failed from a non related component failure in the power on circuit.The Momentum amplifier is designed to shut down at 70c (158f). The unit under test was not close to that temperature.Many amplifiers at higher temperatures than that.If John had continued his test the second amplifier would have passed witout any problems. The Momentum amplifier has more than enough thermal head room for any load or speaker. I was unable to give comment until the unit was returned to me from testing. Thank you for your concern.
Dan D'Agostino
I am sorry that you interpret this as a meltdown. The momentum amplifiers normal operating temperature is 42 -44 degrees c(107-111f) the temperature rise to 48c (118f) is inconsequential. The amplifier in question failed from a non-related component failure in the power on circuit. The Momentum amplifier is designed to shut down at 70 c (158f) The unit under test was not close to that temperature. Many amplifiers operate temperatures at 70c(158f) and above. If John had continued his test the second amplifier would have passed without any problems. The Momentum amplifier has more than enough thermal head room for any load or any speaker. I was unable to give a comment
Until the unit was returned to me from testing.
Thank you for your concern.

Dan D’Agostino
I have a pair of Krell LAT 1000's and would love to hear any comments on whether they'd sound better driven by a set of Krell Evolution One's or Dan's new Momentum 300 monos.  Consider the listening environment a neutral factor in your analysis, if you can, ha.  For the boisterous critics here, I'm a fan of pretty much all of Dan's work.

Best,
Justin
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