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Review and Measurements of Massdrop THX AAA 789 Amp

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The body you hear is the low frequency ps noise. I have af200 which is a better clone of v200 and i have person tested the original or me as well, they both have -100dbv ps noise. Which is very audible to sensitive earphones and will impact other headphones in some ways. -100dbv is audible because it doesn't change along with volume pot.
I'm positive that I hear no noise. But you can have your own opinion, of course. If that is the ps noise that makes the sound of A200 so pleasing to my ears, let it be so, whatever you name it. I need that on my THX very much!))
 

Roen

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I'm positive that I hear no noise. But you can have your own opinion, of course. If that is the ps noise that makes the sound of A200 so pleasing to my ears, let it be so, whatever you name it. I need that on my THX very much!))
If that is indeed the case, the THX is not the amp for you.
 
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If that is indeed the case, the THX is not the amp for you.
Thank you, but I will decide that for myself if you please. I love THX's sound too, it's just that it is not ideal as everything in this world, but I shall try to improve it. If I do not succeed, I will listen to them both getting different kicks from different signatures.
 

Chiv

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I have JDS atom and khadas tone. Any reason to get this to replace the atom (besides build quality) If I don't see myself using balanced?
 

GoMrPickles

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I have JDS atom and khadas tone. Any reason to get this to replace the atom (besides build quality) If I don't see myself using balanced?
I have the Atom and the THX (using an O2-ODAC as DAC); I certainly can't hear any difference between them. I'd stick with the Atom if you're not in a hurry to try the THX. I've only tried SE connections, not balanced.
 

JohnYang1997

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I have the Atom and the THX (using an O2-ODAC as DAC); I certainly can't hear any difference between them. I'd stick with the Atom if you're not in a hurry to try the THX. I've only tried SE connections, not balanced.
Because odac is really really behind. I was shocked how awful it measures. At least get a db magix ac3. Or maybe get a allo katana. If you want something cheap, second hand asus u7 will be leagues better.
 

GoMrPickles

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Because odac is really really behind. I was shocked how awful it measures. At least get a db magix ac3. Or maybe get a allo katana. If you want something cheap, second hand asus u7 will be leagues better.
I'll happily try them if you send them to me. Will they makes the sounds fuller with more bodies? Heavy bodies.

ETA: Fully a joke, obvi , tho I'm happy to try gear for free. I mainly use Spotify and a pair of 15 year old set of Klipsch ProMedia 2.1 speakers, so I'll probably sell the THX once I solder a balanced cable for the 6XX and further convince myself there isn't an audible difference.
 
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Competently designed solid state headphone amps sound very similar, you would be surprised by the results of level matched blind testing and the effect of price and aesthetics over perception.

Feature wise and for the asking price both the Atom and THX789 are good buys, and if a more luxurious version of the Atom with metal chassis and better volume pot gets released at a reasonable price I'm sure it will sell well, too.

You will find the largest differences using different headphones, transducers are still way behind electronics and a perfect set doesn't yet exist, no matter the cost.


Because odac is really really behind. I was shocked how awful it measures. At least get a db magix ac3. Or maybe get a allo katana. If you want something cheap, second hand asus u7 will be leagues better.
 

Veri

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Question to fellow owners, I am currently using se input on the thx amp. When using balanced input, will SE pass-through work? Is there some transformer magic to make this possible, or only with SE input..?
 
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When using balanced input, will SE pass-through work? Is there some transformer magic to make this possible, or only with SE input..?
SE PASS is wired directly to the SE INPUT.

If you really want to, you can rewire it (and void warranty in the process) by breaking internal routing for SE PASS and using jumpers to bridge XLR inputs pins 1 and 2 to the SE PASS jacks.. At least I believe this to be the case.

What are you hooking up to the SE PASS, and what is the source device?

Edit: at this point, it might just be better to use adapters and leave the inside alone. 2x XLR splitters, 2x XLRf to RCA. Bit of extra info here: https://www.massdrop.com/buy/massdrop-x-thx-aaa-789-linear-amplifier/talk/2215137
 
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Nango

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Ridiculous, again sold out within hours.... They are done for me, @amirm stop referencing to that one as it is not freely available, it's nonsense to put more and more people on that amp. Furthermore they should start adding some kind of an enhancement as this design is getting older..... I wish the Neuchrome stuff would be a bit cheaper as we in Europe have to add 1/3 to its price on top due to taxes and other fees.
 
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Managed to get one this morning. Pulled out my CC in the gym and ordered. I am glad I did, because by the time I got to my lab it was sold out.

A question: if I buy a SE to XLR adapter, will I be able to take advantaged of the increase power output when using balanced? Want to drive the HD800 with this amp.

Is the increased wattage due to using the SE vs XLR output, or is it because of the balanced inputs from the DAC?
 

Nango

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@BigBeard An adapter itself will never double the SE voltage that is characteristic for XLR, you still have the same low voltage from the SE now on XLR. If you want to drive the HD800 balanced you need their own cable or one from a third vendor.
 
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@BigBeard the XLR4 will output more power than the SE output regardless of which input you're using. This amp will EASILY drive the HD800 with either output, but if you want to use balanced then you should buy the appropriate headphone cable.
 
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I was debating buying one at work today but decided naw. I just bought the $500 Gilmore Lite mk2 in December, I have no doubt the THX measures better but the Gilmore Lite mk2 is no slouch.

I've debated sending it to Amir for review to see how it measures up but then I would be stuck on my Asgard 2 :(
 

JohnYang1997

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I'll happily try them if you send them to me. Will they makes the sounds fuller with more bodies? Heavy bodies.

ETA: Fully a joke, obvi , tho I'm happy to try gear for free. I mainly use Spotify and a pair of 15 year old set of Klipsch ProMedia 2.1 speakers, so I'll probably sell the THX once I solder a balanced cable for the 6XX and further convince myself there isn't an audible difference.
The thing is, you can hear it. It's just masked by the dac. I have more than 19 friends said db magic ac3 has very wierd but realistic soundstage and vocal being upfront and has body. It's cheap. I measured all of those. including el dac focusritr forte. Only square wave is drastically different. Distortion are all below 0.0003%
 

The Mule

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Ok, I got the email about the Drop, went to the website, and the Drop wasn't active. I thought maybe the email was sent by mistake. :facepalm: Nope, had already ended. Ugh.

Anyway, a question: any thought as to how the THX compares to a Musical Fidelity M1 HPAP? I didn't see any measurements for the MF when I did some looking about, but their other amps seem to measure pretty good.
 
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