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Review and Measurements of Massdrop THX AAA 789 Amp

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Weird, got a used 2019 THX789 today and I seem to like the SMSL SP200 much more. No idea what's up but the 789 sounds dull and uninvolving, like running the AKG K712's from a smartphone but with higher power.
 

Veri

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Weird, got a used 2019 THX789 today and I seem to like the SMSL SP200 much more. No idea what's up but the 789 sounds dull and uninvolving, like running the AKG K712's from a smartphone but with higher power.
Hmm. Never got to hear them side by side, but I'd sure expect them to sound the same.
 

JohnYang1997

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Weird, got a used 2019 THX789 today and I seem to like the SMSL SP200 much more. No idea what's up but the 789 sounds dull and uninvolving, like running the AKG K712's from a smartphone but with higher power.
You gotta match volume and do a AB test. Sp200 has more gain with either gain setting than corresponding mode in 789. Higher gain = louder = more energetic= more involving.
 
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You gotta match volume and do a AB test. Sp200 has more gain with either gain setting than corresponding mode in 789. Higher gain = louder = more energetic= more involving.
Wait. You told me in messages that with amps is better to max out the lowest gain, possibly. So..?? You mean more involving in a worst way?
 
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People like it louder is very common. But from objective point of view higher gain = higher distortion and/or higher noise.
Right. But as you explained me higher gain is just more power but the headroom is the same, is just higher distortion (And i find sound also less detailed, maybe because gain act like a compression overall) so yeah, i also thinked that he was thinking sp200 sound better for diverse gain, maybe he is using 789 balanced in high gain, mhh. Because, well tomorrow i will receive back my thx aaa 789 but i remember it sound lot better than Sp200. My atom sounds better than Sp200 with all headphones (5-6) I tried.
 

JohnYang1997

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Right. But as you explained me higher gain is just more power but the headroom is the same, is just higher distortion (And i find sound also less detailed, maybe because gain act like a compression overall) so yeah, i also thinked that he was thinking sp200 sound better for diverse gain, maybe he is using 789 balanced in high gain, mhh. Because, well tomorrow i will receive back my thx aaa 789 but i remember it sound lot better than Sp200. My atom sounds better than Sp200 with all headphones (5-6) I tried.
That's why I asked him to match volume.
 
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Guys, i may have a problem, can you help me?
I am worried about using my thx aaa 789 April batch i received today( The story is long), the guy who sent it back to me, has sent the new Drop + THX aaa 789 power supply, i have the massdrop April batch, and used of course with his power supply. But I am worried to use my old thx aaa 789 with the new power supply! (Power supply is not changed by MassDrop but by a Head-fi guy, who changed his new, never used power supply with mine, also the box gived me the new eheh) I hope to not damage that way, can a expert confirm me? I will not use it until someone can confirm me, because i'm scared to damage it.
 

Veri

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As long as it is regulated 24V it's fine. If somehow amperage is insufficient it will break up into protection mode.
 
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I will be getting rid of the 789 in favor of the SP200.
Gave both 2 days of warmup but to my ears the 789 sounds just too veiled and dull combined with the Xsabre Pro and SoTM stack, I can't get used to that sound. I tried cranking the 789 higher but still, it keeps its sound signature.
There is nothing wrong with the bass and the highs but the midrange is cloudy, like that typical 80's mosfet sound.
 

Fluffy

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I will be getting rid of the 789 in favor of the SP200.
Gave both 2 days of warmup but to my ears the 789 sounds just too veiled and dull combined with the Xsabre Pro and SoTM stack, I can't get used to that sound. I tried cranking the 789 higher but still, it keeps its sound signature.
There is nothing wrong with the bass and the highs but the midrange is cloudy, like that typical 80's mosfet sound.
Are you being serious right now? An amplifier like this does not have a sound signature of it's own – that's the whole point.
 
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Yes, I'm 100% serious, I don't like the 789. The SP200 is much cleaner on the midrange. I've even matched the levels and only turned the amps off to swap the interconnects.
Maybe with brighter headphones the 789 would do, but the K712 not really.

+
I just found this guy's comparison and his experience with the 789 vs SP200 is bang on.
https://soundnews.net/amplifiers/he...x-789-vs-benchmark-hpa4-battle-of-the-thx-es/
 
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