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Review and Measurements of Massdrop THX AAA 789 Amp

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The correct term is signal to noise ratio and it is in the review:



You can think of it as dynamic range.
Thanks! Now i got it.. Just to be sure: Dynamic range with THX 789 (123dB) and Smsl D1 (126dB) would be something like 123dB overall? Or it's more complex?
 
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Something like 123dB, since that would be the bottleneck.
Thanks.. Would like to know how much 123dB in normal content is useful in normal content/music, but maybe this is not the thread.. I'll use them mostly with Playstation games, can't know the dynamic range of those sounds because i don't think DR of games have been measures, but i think some games could have bad DR while other's nail it (Also, almost all games content music, so i think they have uncompressed music?) .. For example: 123dB DR system is useful for more head room with 90dB DR content? Ok, i realized this question is not correct, might reformule the question in another thread xD
 
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solderdude

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The DR of human hearing when listening to music is somewhere between 70 and 80dB.
This is smaller than the DR hearing can 'handle'.
This is NOT the same as DR in DR ratings of music which says something about the difference in dB between average levels and peak levels.
 
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What do you guys think the possibility is of getting hold of one of these amps within the next year?

Other than paying a ridiculous amount for one off eBay.
 
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Probably pretty good. Flag this thread as "Watched" and someone will post that it's going live before it goes live. Your alert from here will be sooner than Drop's alert. I bet they do another drop in August or September.
 

amirm

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Hi @amirm - updated in what way/s? What's the issue needing re-testing?
Sorry, I post that in the wrong thread. :) I was referring to the monoprice THX amp. I did get a new one and post that review recently.
 

amirm

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Does this amp come with a switching power supply? As in 100-240 volt. Making sure I got everything I need when mine arrives.
I don't have it in front of me but yes, it is a switching power supply so should support universal input voltage.
 

amirm

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I had originally posted this in the teardown thread, but given it doesn't get nearly as much traffic as this thread does, I'll try my luck here. I have one of these that had been left on overnight and was dead the next morning. It won't power up at all. I've tested the power supply and it's good. I even tested the power button and auto off switch with my multimeter and the continuity tested fine with pushing/switching each with the points i tested. I don't know enough about the power on circuit to really do anything there. I read over at headfi of some early ones having issues with the power on circuit. Is there a way to bypass this circuit and use a traditional power on switch to at least rule out anything thing being wrong with the rest of the unit?
 

Music1969

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I had originally posted this in the teardown thread, but given it doesn't get nearly as much traffic as this thread does, I'll try my luck here. I have one of these that had been left on overnight and was dead the next morning. It won't power up at all. I've tested the power supply and it's good. I even tested the power button and auto off switch with my multimeter and the continuity tested fine with pushing/switching each with the points i tested. I don't know enough about the power on circuit to really do anything there. I read over at headfi of some early ones having issues with the power on circuit. Is there a way to bypass this circuit and use a traditional power on switch to at least rule out anything thing being wrong with the rest of the unit?
Have you contacted Massdrop? Is it still under 12 months warranty?
 
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