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Review and Measurements of Massdrop THX AAA 789 Amp

Juhazi

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Just made a preorder of Monoprice AK/THX dac-amp https://www.monoprice.com/product?c_id=120&cp_id=12008&cs_id=1200801&p_id=24459&seq=1&format=2&res=1
Hope that they will deliver to Finland, Europe.... Amazon.de is another supplier of Monoprice products, but this gadget is not on the list.
This will replace my Audio-GD NFB-12 with dual Wolfsons.

Got a message, "we don't deliver to Finland"

So it goes for me. But I'll keep my eye on these desktop AK/AAA combos in Europe!
 

maxxevv

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Check if you have proxy shipping / forwarding services for Finland that have an office in the US.
They are very handy for such things.
 

maxxevv

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Buy it to Amir for review, then he sends it to you.

That's a pretty cool idea. He'll save on shipping and makes sure he gets a properly working set before it crosses 'the pond' to Finland!
 

rajapruk

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And it ships on thursday. I waited freaking 9 months, like a baby! :)
 

wadec22

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Pretty cool. 24hr should now mean perpetual stock with the drop renewing each week day
 

mi-fu

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Just joined the drop!!

Again, thanks Amir for the great review! I now can't be happier. :p:p
 

Jorj

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Joined the drop. I believe that this little black box will be the final word on my desktop rig for a LONG time to come. Unbelievable how well it measures. Anyone want a JDS Element? :)

edit:

I guess I do need a budget SOTA balanced DAC to pair it with, since I already have the DX7s and I'm not a fan of the IMD hump the ESS implementations of late have been showing.
 
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Roen

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Are there any gain / distortion comparisons?
 

Schackmannen

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I couldn't find any information about it in the spec sheet (unless I'm blind) but what's the maximum accepted input voltage into the balanced inputs? Could it handle the max output from the ADI-2 DAC's balanced outputs?
 

Juhazi

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About the Monoprice dac-amp - I became too concerned about the quality of many other Mp products tested, lost my interest this time! Massdrop products looks like higher quality.And, I am very happy with my current Audio-Gd and I listen to it many times in a year with AKG K-601! I prefer speakers, HP is only for those late hour listening sessions that are very rare at my age!
 

Roen

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Joined the drop. I believe that this little black box will be the final word on my desktop rig for a LONG time to come. Unbelievable how well it measures. Anyone want a JDS Element? :)

edit:

I guess I do need a budget SOTA balanced DAC to pair it with, since I already have the DX7s and I'm not a fan of the IMD hump the ESS implementations of late have been showing.

I JUST bought a JDS O2. Good thing I had batteries installed in it, it'll now be exclusively portable duty while this takes up desktop duty.
 

mi-fu

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@amirm , maybe you can share your Massdrop referral code here?

For people who have not signed up with massdrop before, if they read this review and decide to buy one, then both of you get can a $10 credit. :)
 

VintageFlanker

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I couldn't find any information about it in the spec sheet (unless I'm blind) but what's the maximum accepted input voltage into the balanced inputs? Could it handle the max output from the ADI-2 DAC's balanced outputs?
I don't think it needs to. Usually, XLR outputs on DACs are rated at 4V. You can simply use a clean +13db ref revel to almost approach this (3,46V). The THX seems to have plenty of power. I do think it would need to be feed louder.
 
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Roen

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This amp isn't fully differential right?

I could connect balanced input -> SE out and SE in -> balanced out right?

I don't need balanced in -> balanced out and SE in -> SE out (forgetting passthrough for a moment)
 

BurritoJustice

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I couldn't find any information about it in the spec sheet (unless I'm blind) but what's the maximum accepted input voltage into the balanced inputs? Could it handle the max output from the ADI-2 DAC's balanced outputs?

Maximum input level is just over +19dBu, but you cannot use the third gain setting. If you want to use the high gain then I believe it can be no higher than about +9dBu. If you check the massdrop thread for posts by the THX engineer he goes further in depth.
 
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amirm

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andymok

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I don't think it needs to. Usually, XLR outputs on DACs are rated at 4V. You can simply use a clean +13db ref revel to almost approach this (3,46V). The THX seems to have plenty of power. I do think it would need to be feed louder.

They mentioned somewhere in the comments, says around +18/19dBu I believe
 
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