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Monoprice Monolith THX 887 Balance Headphone Amp: New Champ?

trl

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#42
Like Ralf asked already, I would love to see some guts from inside, close-ups if possible.

This is a real wire with gain indeed, hope the internals will not disappoint us in any way (like not marked opamps and black traces on black PCB, 'cause this means it's hard to repair).

Thank you!
 

maxxevv

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#43
Wow so slightly less noisy than even the Massdrop THX amp. My only concern was that you tested the previous THX amps at 5.8V output at high gain rather than 4V output on medium gain on this THX 887 amp (For historical reason, I am running high power headphone amps at 5.8 volts output using XLR input at 4 volts).

Is it a fair comparison this way?
Good question!

But it also depends on whether the output numbers are being dominated by noise or dominated by distortion. If its dominated by noise, then a higher voltage would give a better reading, the reverse being true if its dominated by distortion.

THX 789 :



THX 887:



If we look at purely the SNR figures, supposing the 789 is at 5.8V :



And the 887 is at 3.9~4V:



The SNR figures being essentially identical give and take measurement fluctuations, the 887 seems to have a better SNR figure.

BUT, as you pointed out, the gain modes are not the same, so there in lies the 'unknown'.....
 
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trl

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#44
Seems that we're comparing 5.8V RMS with 4V RMS; perhaps a new 4V RMS measurement will lower the background noise a little bit and lower the harmonics too. However, both units are wires with gain, nothing to complain for sure.
 

JohnYang1997

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#51
Indeed. I am tired of recommending the Massdrop THX and then be told people can't get them. Maybe competition will also force them to increase volume.
Can we get a spectrum of 4V into 32ohm? 0.5W
 

maxxevv

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#55
My THX AAA 789 arrived today. It's a great amp. The difference between the Drop and the Monoprice it to small to be of any concern IMHO.
Its not an audible concern unless there are some major topography differences., which is not likely. No difference really if one already has the 789, as mentioned, its really just an alternative, equivalent amp to the 789 at an equivalent price and maybe slightly different aesthetics.

Not a "better amp at any price" thing anyway.
 

FrantzM

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#56
Only annoyance is that it can't be used as a preamp... The Benchmark is also preamp with balanced outputs. The JDS Atom is also a preamp but with single ended output.

The real advantage with the monoprice version, (IMHO they're the same) , is that you can return if you happen to not like (unlikely :p). THe prices being the same too.. I would go with the Monoprice.
 

JohnYang1997

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#57
Only annoyance is that it can't be used as a preamp... The Benchmark is also preamp with balanced outputs. The JDS Atom is also a preamp but with single ended output.
You can certainly use it as a preamp. And a more than capable one. Just you need to unplug your headphones.
 

FrantzM

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#58
You can certainly use it as a preamp. And a more than capable one. Just you need to unplug your headphones.
True but you have to make/find some new cables/adapters... then unplug/plug cables every time you want to use your speaker system... that can become quickly a major annoyance.
 

maxxevv

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#59
There's always the option of passive switcher boxes. Just need XLR-4 to XLR-3 converter cables as most of the cheap switch boxes are only in XLR-3 and RCA.
 

Tks

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#60
119.. didn’t think we’d get that outside of the digital realm. Nice!
 
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