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Monoprice Monolith THX 887 Balance Headphone Amp: New Champ?

deafenears

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Wouldn't be measurable by the AP x555. I believe max SINAD is 123db, or ...
123db per loopback:
I have one that I did that is close enough:

View attachment 29765
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AndrewDavis

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" it is my absolute pleasure to recommend the Monolith THX AAA Balanced headphone amplifier. It delighted me to see a company dedicated to absolute excellence and full transparency to our sources and content. This is a type of product you buy once and you are done. "

My THX AAA 789 is set to arrive on Thursday and now I'm contemplating slitting my wrists. :(

Me too, but I think we're fine.
Oh no. You have an exceptional product. Don't get buyer's remorse that way. The monolith is for people who have not yet managed to get a Massdrop one.

I have a THX789 coming I'd the same shipment and ,that's my thinking. They're both fantastic. Our cup runneth over with great audio equipment! Also the sleeker, industrial-ish look of the Massdrop version seals the deal for me.
 

BostonJack

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Oh no. You have an exceptional product. Don't get buyer's remorse that way. The monolith is for people who have not yet managed to get a Massdrop one.

My Drop THX 789 is on the delivery truck. I appreciate both Amir's testing excellence and the narrow horserace at 117 vs. 119 db. Good to have a unit that doesn't require such an uncertain delivery schedule. No buyer's remorse on my part as I am absolutely certain that I can't perceive distortion differences at that low level.

Its like Porsche came out with a 911 model with 6 more horsepower. Ok, bravo for the new owners, but that doesn't obviate the excellence of the prior vehicles.
 

mmicko

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Any adequate Balanced DAC in similar price level for pairing ?
The best once from Amir's SINAD list cost over 1k USD :-(
 

phpp

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Really curious to see the inside. From the outside, it looks like a Massdrop board with another box.
@amirm are you planning a teardown?

The position of buttons and dial on the front, even the position of the LED are identical. The back is too. This has to be a new revision of the 789 PCB in another case, right?? I would love to have a look inside as well.
 
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maxxevv

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Any adequate Balanced DAC in similar price level for pairing ?
The best once from Amir's SINAD list cost over 1k USD :-(

Cheapest balanced DAC with "close enough" performance ? SMSL SU-8 v2.

Cheapest balanced DAC with equivalent performance ? Sabaj D5. But it already has a fairly decent headphone amp, so may not be what you need.
 

Dana reed

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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.
The one I pre-ordered in June will arrive tomorrow according to FedEx!
 

Noob

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Any adequate Balanced DAC in similar price level for pairing ?
The best once from Amir's SINAD list cost over 1k USD :-(

Sabaj D5 comes to mind. It's $70 more than the monoprice amp, but it has some very impressive measurements. The built-in headphone amp it the weakest point of the design, and this monoprice amp would be an ideal amp pairing for it.

I also second the SU-8 reccomendation. Unless you have amazingly good ears and a superbly revealing pair of headphones, you won't notice a DAC upgrade from the SU-8.
 

Svperstar

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Kinda temping but I don't think I really need to go balanced. My current setup I could easily turn up the Gilmore Lite mk2 with any of my headphones to the point I would get perm hearing damage, so why would I buy this and a balanced DAC AND recable everything?
 

ayane

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suttondesign

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Is there any reason, such as overheated capacitors or whatever, that these sorts of amps will see a dropoff in measured performance over time?
 
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amirm

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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?
I forgot to comment on this as I tested this unit a few days ago. I did test it both ways and results were essentially the same. For consistency moving forward, I chose to stay with unity gain in both unbalanced and balanced as I have been doing for a while.
 

Grattle

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Is this "fully" balanced amp? (MD 789 is not)

This was my first thought upon seeing this - does it have true balanced operation throughout? I guess it really doesn't matter for my use, but I'm curious.
 

JohnYang1997

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Still think 0.3 uV is the gold standard for output noise level, huh? =)
I wasn't aware of any gold standard. I used -130db to leave some room for distortions. I think I have achieved that with 32ohm load 0.5W, -127db for 8ohm 0.5W.
 
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