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Review and Measurements of Massdrop THX AAA 789 Amp

Scarlettlol

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Both Heresy and 789 are essentially distortionless. They won't sound different.
Why do you 'loathe' the heresy? Also your post reads like you're high on a lot of caffeine lol.

I don't know why the review says it's distortionless, it's not. At least not my unit. I compare/d the output of it vs my Yamaha receiver (class B) and my receiver has no distortion (or next to nothing) vs the Heresy lots of it.
 

Nango

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I hope you can help me out guys:

Last 3 years or so all I have heard is grain/sand, harshness, distortion, noise, piercing highs, whatever you wanna call it, I have bought and sold a bunch of gear I am so tired of doing so, even if Amazon and/or other sources allow you to return the product for free (still, takes time and
it's a little bit stressful).
Even when I make my homework: reading lots of info, reviews, youtube videos, etc, I end up being just disappointed.
Just a recent example: a Youtuber Zeos (Z reviews) swore that the Phillips Fidelio were the "best" headphones ever and that we were the most stupid person in the world if we didn't buy them... long story short, they arrived from Amazon, I opened them, plugged them in, played 5 songs,
put them back in the box and returned them. To me they were the worst piece of sht ever made in mankind history. (Too bad, they were beautiful looking).
Now I don't return to his channel anymore...

Currently I have:

Duet (Apogee last gen) interface (it has balanced outputs, but they are 6.5 mm not XLR :( )
Yamaha receiver R-S02 //apparently Class B (I bought it for some NS-244 speakers, that I swear sounded powerful and amazing when I bought them).
Modi 2 USB + Heresy
And recently bought a iFi Silencer (which I swear does something, it has helped me clean, or so I believe, jitter from the Modi/Duet). Signal feels cleaner meaning more defined, helped with instrument separation.
Headphones: Sennheiser HD650 (recently bought 2, they were a bargain, for me the best overall headphones so far), HD599, Beyerdynamic DT990.

And I am not happy at all. With the iFi at least I feel some sort of improvement.
I like more the Duet than the Schiit combo, but it sounds to me it has exaggerated highs, and somehow it manages to "obscure" vocals a little bit.
(electric guitars sound as they should, great timbre, VS the Modi + Heresy combo, they sound like azz, timbre is not respected at all).
Line outputs sound different than the headphones output.
I have run the Duet's line outputs into my Yamaha receiver and into the Heresy (separately) and the Heresy is just anemic. The Yamaha receiver sounds fuller/warmer not anemic (night and day of a difference vs the Heresy) but I still feel I hear a little bit of distortion/noise, no matter the volume. I call this noise like some sort of saturation (as I use lots of plugins for music mixing, this one I feel is the perfect example of a word/description, and saturation is distortion. Btw, I loathe saturators. Probably would like them if I felt I had first a clean/distortionless signal)

I mention the Heresy being anemic because I fear I would have the same issue with the THX AAA 789? Reading the output power/impedance
specs (which I don't understand at all but they seem similar between them).

But I am interested in the THX AAA 789 because it's basically distortionless?

Hell, sometimes I grab my headphones, put them on, and even if I don't hear anything (meaning I don't play any music/sound), I feel sometimes something that makes me just remove them off my head.

Also the THX AAA 789 is supposed to be not only distortionless but clean and almost flat, meaning it will respect TIMBRE ?

So, from what I read the THX AAA 789 has what I am looking for?
It has more power than the Magni?
It's pretty much distortionless?
It's very very clean?
It's FR is flat (meaning it will respect the timbre of my recordings)?
It's got balanced inputs which I can use with my Duet's balance outputs?


I want it loud, powerful, clean, timbre respectful. I focus on Vocals, snares, kicks, bass (as in very well defined), cymbals (silk sounding, not metallic //more than they should, I mean, they are made of metal, I know // ) any brass instrument. I focus on instrument separation, not a messy/muddy presentation.

Or having the Heresy, it would be reduntant, maybe they are very near each other sound/specs wise?

Maybe I won't ever like anything for good? I swear I don't continue recording stuff because I just don't feel like turning on my gear since I don't hear nowhere a decent sound. Something's always off (specially with the aforementioned distortion/saturation I feel I hear, no matter the volume level).

Note: My Duet's sound is not that is bad //specially through headphones// , but either have to listen to it at low levels or I feel it gets nasty at medium/high volumes sometimes.
Has great bass projection (not exaggerated, to me sounds as it should, but from mid highs? to highs it kinda gets into harshness/saturation/distortion?)

P.S. Just running Bluetooth into my Yamaha's receiver, sending the output into the Heresy, it sounds with added distortion, whereas the Yamaha receiver's own headphone output sounds almost with no distortion in it. Night and day difference.
Using Audioquest red RCA cables, if you must know (forgot about mentioning I am using those, which yes, sound "better" or at least different than
Amazon's Editors Choice RCA cables).

I have written this kind of Thesis in several places with no answer so far.

Never heard a better description of those Philips X2 ...Great!!!!!
 

Veri

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I don't know why the review says it's distortionless, it's not. At least not my unit. I compare/d the output of it vs my Yamaha receiver (class B) and my receiver has no distortion (or next to nothing) vs the Heresy lots of it.
Have you considered your receiver has a very high output impedance which has a big impact on how you perceive bass?
I think you are confusing the correct one and the distorting one.
 

yahrightthere

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Not sure what is going on, received a new 789 today, connected my PC onboard sound out via a 3.5 mm to RCA cable to the SE in on the 789.
Turned the PC sound setting volume to max, set the VLC media player volume to max, turned on the 789 plugged in Sennheiser HD 598 & played music on low gain & had to max the volume on the 789 to get it loud enough, the max volume on the 789 was a bit lower than when i directly plug my HP into the PC.
I then tried it on mid gain & the 789 got a little louder than when directly plugging my HP into the PC.
On high gain the sound was a bit distorted when volume was maxed out & was too much for the HD 598.
Also have HD 6XX & that was the same except that on high gain the max volume wasn't to much for the HD 6XX, but the sound still seem distorted.
At one point switching back & forth between the PC & the 789 I lost the sound in the right channel in the HP from the 789.
Shut down & unplugged the 789 for a minute or so & had the sound in the right channel again, but is this normal? perhaps a defective unit?
If not then i must say i am a bit disillusioned with stand alone HP amps, I've 3 AVRs that drive my HD 598 to distortion well below max volume.
I am older & my hearing has no doubt deteriorated, but can't at the moment see why i spent the money on a stand alone HP amp when my AVRs seem more than adequate, are HP amps just hype?
I'll continue to do more testing over the weekend, but if there doesn't seem to be a difference between a HP amp & a AVR HP out then the 789 will go back for a refund.
TIA for any help or light you can shed or share about this.
 
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ZeDestructor

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Not sure what is going on, received a new 789 today, connected my PC onboard sound out via a 3.5 mm to RCA cable to the SE in on the 789.
Turned the PC sound setting volume to max, set the VLC media player volume to max, turned on the 789 plugged in Sennheiser HD 598 & played music on low gain & had to max the volume on the 789 to get it loud enough, the max volume on the 789 was a bit lower than when i directly plug my HP into the PC.
I then tried it on mid gain & the 789 got a little louder than when directly plugging my HP into the PC.
On high gain the sound was a bit distorted when volume was maxed out & was too much for the HD 598.
Also have HD 6XX & that was the same except that on high gain the max volume wasn't to much for the HD 6XX, but the sound still seem distorted.
At one point switching back & forth between the PC & the 789 I lost the sound in the right channel in the HP from the 789.
Shut down & unplugged the 789 for a minute or so & had the sound in the right channel again, but is this normal? perhaps a defective unit?
If not then i must say i am a bit disillusioned with stand alone HP amps, I've 3 AVRs that drive my HD 598 to distortion well below max volume.
I am older & my hearing has no doubt deteriorated, but can't at the moment see why i spent the money on a stand alone HP amp when my AVRs seem more than adequate, are HP amps just hype?
I'll continue to do more testing over the weekend, but if there doesn't seem to be a difference between a HP amp & a AVR HP out then the 789 will go back for a refund.
TIA for any help or light you can shed or share about this.

I just tried mine with my old computer (Z77 Sabertooth) and my DAC's SE output (SDAC-Balanced) and it's all working fine for me - my ATH-SR9 gets very loud with no distortion on all 3 gain levels.

It seems that your 789's protection circuit is being tripped somehow (temporarily disabled channel looks like some kind of protection kicking in), so I'd suggest you try your 789 with some other source, like your phone or your AVR's pre-out or similar.
 

Jimbob54

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Not sure what is going on, received a new 789 today, connected my PC onboard sound out via a 3.5 mm to RCA cable to the SE in on the 789.
Turned the PC sound setting volume to max, set the VLC media player volume to max, turned on the 789 plugged in Sennheiser HD 598 & played music on low gain & had to max the volume on the 789 to get it loud enough, the max volume on the 789 was a bit lower than when i directly plug my HP into the PC.
I then tried it on mid gain & the 789 got a little louder than when directly plugging my HP into the PC.
On high gain the sound was a bit distorted when volume was maxed out & was too much for the HD 598.
Also have HD 6XX & that was the same except that on high gain the max volume wasn't to much for the HD 6XX, but the sound still seem distorted.
At one point switching back & forth between the PC & the 789 I lost the sound in the right channel in the HP from the 789.
Shut down & unplugged the 789 for a minute or so & had the sound in the right channel again, but is this normal? perhaps a defective unit?
If not then i must say i am a bit disillusioned with stand alone HP amps, I've 3 AVRs that drive my HD 598 to distortion well below max volume.
I am older & my hearing has no doubt deteriorated, but can't at the moment see why i spent the money on a stand alone HP amp when my AVRs seem more than adequate, are HP amps just hype?
I'll continue to do more testing over the weekend, but if there doesn't seem to be a difference between a HP amp & a AVR HP out then the 789 will go back for a refund.
TIA for any help or light you can shed or share about this.

Have you tried a different source (any of your AVRs got RCAs out?, CD player , even phone HP out) and a different cable into the 789? Anything to rule out a poor connection to PC and/or faulty 3.5- RCA cable. (EDIT- as poster above says.)

What files are you playing? Any odd settings engaged with Windows audio settings or VLC - spatializers and the like?

This forum is littered with folk who plug PC out into HP amps and are dissatisfied but its very hard to troubleshoot remotely as so many reasons why what comes out of the 3.5mm on the PC may be garbage/ limited/ distorted.

Unless the 789 is actually faulty, you shouldnt need high gain for the 598 and certainly shouldnt get distortion from the amp.
 

Jimbob54

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Have you considered your receiver has a very high output impedance which has a big impact on how you perceive bass?
I think you are confusing the correct one and the distorting one.

Grain, grain everywhere.
 

yahrightthere

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Have you tried a different source (any of your AVRs got RCAs out?, CD player , even phone HP out) and a different cable into the 789? Anything to rule out a poor connection to PC and/or faulty 3.5- RCA cable. (EDIT- as poster above says.)
What files are you playing? Any odd settings engaged with Windows audio settings or VLC - spatializers and the like?
This forum is littered with folk who plug PC out into HP amps and are dissatisfied but its very hard to troubleshoot remotely as so many reasons why what comes out of the 3.5mm on the PC may be garbage/ limited/ distorted.
Unless the 789 is actually faulty, you shouldnt need high gain for the 598 and certainly shouldnt get distortion from the amp.
Thank you guys for the replies.
I am returning the 789.
The files are MP3, player on the PC are VLC & Rhythmbox without any kind of augmentation to the audio settings.
Windows was not used in the evaluation of the 789, I do not use Windows if i can help it.
I do have two 3.5 -RCA cables with no difference to any of the equipment used.
A older Sony DVD/CD player, note 8, PC, HD598 & HD6XX are the equipment used.
I did not connect the 789 to the AVRs.
The 789 In high gain, I meant to say the noise level seemed more noticeable, not distorting as previously stated.
The same results as above, the loudness volume wasn't sufficient enough as compared to the AVRs to justify the money spent.
Again my thanks for your replies
 

ZeDestructor

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Thank you guys for the replies.
I am returning the 789.
The files are MP3, player on the PC are VLC & Rhythmbox without any kind of augmentation to the audio settings.
Windows was not used in the evaluation of the 789, I do not use Windows if i can help it.
I do have two 3.5 -RCA cables with no difference to any of the equipment used.
A older Sony DVD/CD player, note 8, PC, HD598 & HD6XX are the equipment used.
I did not connect the 789 to the AVRs.
The 789 In high gain, I meant to say the noise level seemed more noticeable, not distorting as previously stated.
The same results as above, the loudness volume wasn't sufficient enough as compared to the AVRs to justify the money spent.
Again my thanks for your replies

Sounds like you received a faulty unit. Unlucky, but a replacement should sort you out.
 

yahrightthere

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Sounds like you received a faulty unit. Unlucky, but a replacement should sort you out.
Perhaps the 789 was faulty, had that right channel drop a couple more times when switching between inputs from different equipment & the HPs.
Don't want a another 789. The 789 was for a desktop set-up, for now I'll stick with the AVR, may at some point go with a dac & amp combo.

Am looking to go with a dac/amp combo to be used more as a pre-amp with the XLR going to active speakers & rca going to a sub, maybe two, it's for a family room set-up & that's the priority, the desktop is secondary.

Waiting to see if Topping comes out with a D90 & A90 combo with a lower hp impedance than the DX7 pro, not that a hp amp is really needed or required, but it never hurts to have one in case of shit happens.
 

RickSanchez

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Waiting to see if Topping comes out with a D90 & A90 combo with a lower hp impedance than the DX7 pro, not that a hp amp is really needed or required, but it never hurts to have one in case of shit happens.

Topping A90 output impedance from Amir's measurements ...

"Output impedance is a very low 1.3 ohm which is about the limit of what I get with my current test jig: "


This is far lower than the 6.2 Ω he measured for the DX7 Pro.
 

yahrightthere

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Thanks, I was aware of & read Wolfs post on the A90 & recently Amir's review of the A90.

To the best of my knowledge though the A90 does not have a remote that can control the volume, perhaps i should be looking for a preamp that fits my needs.
 

ZeDestructor

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Thanks, I was aware of & read Wolfs post on the A90 & recently Amir's review of the A90.

To the best of my knowledge though the A90 does not have a remote that can control the volume, perhaps i should be looking for a preamp that fits my needs.

The RME ADI-2 is probably the most suitable for you.
 

yahrightthere

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The RME ADI-2 is probably the most suitable for you.
I looked at the RME, it's a bit pricey for me, plus I'm trying to utilize a Logitech remote & the RME is not on the Logitech list of vendors/manufacturers that is supported.
The DX7 pro would fit my needs better as it is on the Logitech supported list, & the cost is less than the RME.
 

ZeDestructor

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I looked at the RME, it's a bit pricey for me, plus I'm trying to utilize a Logitech remote & the RME is not on the Logitech list of vendors/manufacturers that is supported.
The DX7 pro would fit my needs better as it is on the Logitech supported list, & the cost is less than the RME.

You can train the Logitech remote, so that's not an issue. Price-wise it's a bit steep, yes, but you get a bunch of stuff the dx7pro doesn't have, like on-board dsp/eq and relay volume control. You also originally mentioned the A90/D90 combo, which are much more comparable to the adi2 dac (not the adi2 or adi2 Pro, my bad on that)
 

MC_RME

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I looked at the RME, it's a bit pricey for me, plus I'm trying to utilize a Logitech remote & the RME is not on the Logitech list of vendors/manufacturers that is supported.

???

I use my ADI-2 Pro and ADI-2 DAC with an old Harmony One and 350.
 

mkarikom

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I really like the industrial design of this unit both in terms of aesthetics and avoiding elements that needlessly increase cost. Compared to this, many items which employ a similar level of technical prowess at reasonable prices appear "busy", while using case elements which are similar or even more involved process-wise. As @amirm stated, the "serious" look is an important part of overall quality and really precludes e.g. multiple rounds of [lathe] turning for various anodized pot dials to add bling (I'm looking at you, S.M.S.L).
 
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yahrightthere

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In the interest of keeping this forum related to the 789 this will be my last post about other equipment.
As I’m fairly new here I am not sure if there is a more appropriate forum to post about various other equipment, I will explore further when I have the chance.
You can train the Logitech remote, so that's not an issue. Price-wise it's a bit steep, yes, but you get a bunch of stuff the dx7pro doesn't have, like on-board dsp/eq and relay volume control. You also originally mentioned the A90/D90 combo, which are much more comparable to the adi2 dac (not the adi2 or adi2 Pro, my bad on that)
??? I use my ADI-2 Pro and ADI-2 DAC with an old Harmony One and 350.
I do appreciate all the advise, & will take the RME ADI-2 in consideration as I am looking at the Matrix Audio X-Sabre Pro which is a bit more than I want to go & maybe overkill for my needs.
I have a Logitech 665 that I have tried several times to program for my Swan M300 with poor results.
The volume adjustment does not work correctly & the mute does not work at all unless I go to the device directly which is a pain to get to & have to press several other commands to be able to control the device correctly.
So my search continues, I am in no rush & as such a HP is not really needed or required, if it is I can connect to my TV via BT as not to disturb the household, as again this is for the family room where movies and music are the main stay.
 
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