Massdrop x THX AAA 789 Amplifier - Official Thread

Sound-wise, it seems this would mainly add in a bit of distortion and make the output replicate a less-clean SS amp. You might achieve a similar tone for $100 with a Schiit Magni 3+ used normally.

Design-wise, I’d be concerned about maxing out an electrical product that the creators did not expect to run at max all the time. Was everything designed and tested for this use case? I don’t know. Stereo power amps with a simple on/off switch are expected to run at one setting.

My everyday solution to amp tone and delivery is to have 1 DAC routed through a switch and several amps. Then, I quickly swap and match the amp to the headphones in use. I do agree that the 789 is not ideal for all headphones.

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Ah, that makes sense.

I am actually thinking about upgrading from the 789 in the near future but as of right now it’s the only one I’ve got…well I guess I can count the rme headphone out as another one too

What switcher do you use?

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For casual use this or its cousins works fine:

Schiit also makes the Sys, but it only has two input settings.

https://www.schiit.com/products/sys

For critical use take the switcher out of the signal chain.

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I just happened to be reading the RME thread ADI-2 thread recently, and Torq recommended the opposite. Take a look at this post, or just read through the whole thread, as quite a few people had the same question as you, which is why I remembered this:

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There’s a lot of technical stuff there I don’t understand yet. But he actually recommended the way I did it too. He said either do what I did or set the rme to -5 or +1 for the ref level.

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I just realized recently the newly announced burson soloist 3x amp has a specific feature for bypassing its volume control. Sure you can do it by maxing all the “knobs” with other amps but cool nonetheless!

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I just bought the thx 789 a couple of days ago and i was expecting a powerfull amp because of some review i watched online. but when its significantly less powerfull (compared to my asgard 1) i can drive my 4XX on the 3rd gain at almost max volume (single ended) without distorton or pain. i mean i wouldnt listen to it at this level but i could.

When i compare to my asgard 1 with which i can literally explode my 4xx. i can’t go pass 1 O’clock which is like 60% od the asgard knob or my ears will start bleeding and the headphones could be damaged.

Its not that i need my music to be played loud but as i say i was expecting a shit ton of power and im asking myself if i didnt got a faulty unit

Hey Shaun,

Thought I’d point out something about what you said.

The range of the dial has nothing to do with power of the amp. The 2 potentiometers almost assuredly taper the resistance differently.

For example, at 50% on the volume dial, one pot might be adding 20 or 30% more resistance than the other one.

Unless the pots are identical make/model/spec (and they aren’t) then judging amp “power” by volume dial location is very inaccurate.

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Some amps have more gain than others. My trashy, cheap Bravo Audio V2 ($55 today) is one of the loudest amps I’ve ever used. With a standard DAC line-out, the useful volume range is from 7 o’clock to 9 o’clock at most. Setting it at 12 o’clock would likely blow out many headphone drivers. However, its massive gain results in terrible sound quality issues. I describe it as a “quantum amp” – volume jumps dramatically when it should not.

The 789 has three gain settings to match the knob with the needed output level, but it always maintains its neutrality/clarity/accuracy/brutality. Some less accurate amps (certainly the Bravo V2 and perhaps the Asgard 1) may be perceived as louder due to distortion spanning frequencies. The 789 delivers narrow, precise amplification across all parts of the spectrum. To my ears, the Magni 3 and 3+ blur some frequencies and make the high range sound too loud.

Finally, I suggest that you compare your listening volumes with a decibel meter. They are freely available as smartphone apps, and could verify whether the output levels are similar while your perception differs. Or not. For greater precision you might buy a dedicated dB meter.

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Wow thank s for that insight i get when ur name is ProfFalkin .

@generic i can tell the asrgard start to distort when i push it higher my logic was more mw was meaning more decibel but the 789 doesnt make any of my headphones distort even an easily drivable elegia can be way too loud without distorting on the 789.

I guess whats u giys are saying is the 789 is not faulty?

The 789 is likely mechanically fine. Its absolute focus on accuracy is a double-edged sword. Ignore what the data people say about the need for the best measurements and listen with your ears.

I like it with troubled headphones that need technical assistance, but hate it with many headphones too. Also, it’s intended to be a balanced amp, and its power will double in the balanced configuration.

The 789 tends to force you to focus on small details over the broad tone and delivery. I don’t like it with most planar headphones myself, but keep it because I do like it with some dynamic driver models.

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Faulty? Probably not.

Good/enjoyable? That’s open for interpretation, but imo, no.

Have fun!

@Shaun_Beauvais Both of @generic’s last two posts were great nuggets of wisdom. Heed is advice.

Just my $0.02.

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::slapping head:: And here I thought it’s because his last name was Falkin, and he’s a professor. But I’ve seen him on the Headphone show, and now I keep thinking Ludwig Von Drake.

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I suspect there’s a (deliberately) misspelled early 80’s techno-thriller reference being missed here …

That, or I am overdue for a nap.

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Nothing deliberate, but I suggest. 1) Drink, 2) watch the video 3) Ponder what it would be like if they had recorded it so that your RAAL setup could do it justice.

We are definitely at odds in our interpretations.

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I wanted to reply when I got home, but my computer has been acting strangely lately, and I figured sooner is better than later.

wargames-wopr

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Hello, “Joshua” …

(Complete with Commodore VIC-20 text).

Nice to know I wasn’t too far in the bag …

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Would you like to play a game?

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