What speakers were you using? That would play a role. I think @LeDechaine was mainly talking about the speaker out’s if I’m not mistaken (I could be).
Edit: you just answered that question, nvm
I just did not like the speaker out on the mx3, and honestly that’s my bigger complaint with the unit. I just think that if you don’t need a speaker amp that there are now better deals for dac/amps for headphones
I edited my post to clarify. I never tested it much on speakers. I ran a short test on the slave unit of my XTZ Tune 4 monitors. But then again I don’t like those speakers that much, I’ve had a hard time to get their accoustics to sound well in my room so I’ve since delegated the MX3 to be an exclusive headphone amp.
In hindsight I should have gotten the DX3 Pro, but it had some quirks over the MX3 that I didn’t find appealing. So in the end I just settled for the MX3. The DX3 sitting at $200 just wasn’t worth it in my book.
EDIT: To clarify further. I’ve used Audeze LCD2 Closed-Back, Fostex T60RP, Sennheiser HD700, Tin T2, Klipsch HP-3 and Denon AH-D5000 on the Topping MX3 and they all sound great. The T60RP are arguably hard to push real good, but they still sound fantastic even if I have to approach near 0dB output levels to get them to blow my head off. Comfortable listening levels on the T60RP is around -16 dB.
Yup. Distortion starts at 63dB for the speaker outs. It’s 82dB for the headphone out.
I never heard distortion from the headphone outs of my audio interface or phone, distortion starts at more or less 95dB for both. I don’t know my “this sounds like crap” threshold. 
I nearly forgot… First, CD-quality 16-bit audio needs 98dB SINAD.
Basically, if you have 98dB SINAD, your CDs always will sound perfect – in theory.
Also nearly forgot, but ASR has a lot of power amplifier measurements, too. This is the most recent list.
ASR sub-forum for power amps: https://www.audiosciencereview.com/forum/index.php?forums/audio-power-amplifiers.47/
Annnd nothing will measure better than your smartphone headphone out (95dB SINAD, let’s say) unless you pay 500$US. Lol. Damn. Passive speakers are cheaper, at least…
Measurements aren’t everything lol, let’s not get too involved
Honestly I just absolutely don’t know where it starts to sound bad. I know my smartphone headphone out and my audio interface are 95dB SINAD, and both sound great. Apparently 98dB is basically theoretical bit-perfect output. And I know my old AVR sounds different. Not as clean. My guess is it’s because it has way lower than 95dB SINAD. So I’d stay in that 90dB+ range…
But apparently, staying in that 90dB+ range with passive speakers, costs, like, 5 times the price.
Yes, speaker amps are a bit different 
Found this. Someone measured chi-fi speaker amps.
FX-Audio D802 is in the list. 80dB SNR, 2x80w. 100$USD. D802C pro has rca/coaxial/optical/usb in and nfc/bluetooth+aptx. Nice. Just no headphone out.
Otherwise, there’s the FX502S Pro in the list, but it’s only an amp. 50$ for RCA in/speaker out.
Edit: Don’t.
The FX502SPro falls way short of its 70 watt spec and produces just 37 watts before clipping.
That’s about it for cheap-but-good amps for passive speakers.
Holy crap, a lot of replies and it has been days. I must say, the information that you guys have provided to me can be proven useful and will give me a wide range of ideas when it comes to DAC/AMPs combo. I overall appreciate the suggestions.
I’m glad you see this as useful and not a hijacked thread lol
well it was almost like one, but you got to appreciate the every varying knowledge that everyone has here.
Yeah sorry, I was curious about all the “budget” dac/amps for passive speakers for me and one of my friends, I didn’t knew if you were interested in passive speakers too and I just thought, well, this thread is going to be a good source of info for everyone starting in hi-fi audio. 
Imo those starting out in audio shouldn’t really worry about the measurements and just enjoy the music. Not saying they should settle for flaws, but measurements shouldn’t be a priority
Sorry, as I said, I don’t really know the threshold where it starts to suck.
I’d still avoid 57dB SNR speaker amps because, damn, 10-to-20 year old AVRs do 80dB SNR.
Use measurements to be sure you don’t buy crap, but don’t pay 100$ more for the 80dB SNR one because the other one is only 79dB SNR. 
Yeah, I think you can get a better value buying a used or refurbished receiver then one of the small entry level amps like the mx3. But some people like stuff like that for desks, and something like the ad18 makes more sense to them, and it’s fine as long as they don’t listen loud
You are not alone in terms of feeling new to Hi Fi audio in general, I myself can still be considered as a newbie when it comes to these things. Sure, I know some audio brands that can provide the sounds you are looking for, but overall there are things out there that are obscured and yet to be find as a diamond in the rough. I never knew the brands Tin, KZ, Fiio, Topping and Dragonfly even existed, and with this has provided me more open mindedness and as well new things to consider. So don’t get too intimidated when you’re overall new to this because back then I was too. Also I am still saving up for the DAC/AMP I want, Fiio and Topping are the options I have for now.
Yeah, there’s alot to take in and consider, with a ton of different options that most people can’t reasonably try, so it gets overwhelming lol
also trust your own ears, and let people’s opinions serve only as a gauge for you to be the item you want like, never get too influenced on other people’s different hearings about it.
