Why did the SMSL A50 Pro both surprise AND confuse me?

[@hammer-and-thumb]

The Dayton Audio MKS4 is a passive subwoofer you can buy that works pretty well. Instead of the four 4" drivers taking the place of an 8" woofer it's more like a 6.5" woofer, but it plays deep enough and just loud enough to combine with good passive speakers, and it has a slim form factor with vibration canceling from the mounting of the four 4" drivers.

[@ForeverAnalog]

Thanks for sharing and watching!

[@jamesstroup7095]

I purchased this amp as a sound bar replacement. I have a decent 2 channel hifi setup and I don't want to put extra hours on my tubes just to watch TV/movies. Also I plan on pairing this with the mkxs4 passive sub from Dayton audio. Will report back after I get this up and running

[@glitch10]

Been using this for about a month now and pretty happy with it, luckily for me my Sub supports multiple input but i had to raise my gain to almost max, gave me a wider sound stage and phantom center is strong ASF and positioning is crazy, DTS on PS5 is more immersive and Dolby was a real step up from using spacial audio with Netflix, i left everything at zero only changing HP to around 110hz and(towers full range) and LP between 40 -55hz. I'm Happy with purchase cause it's really punching up.

[@ForeverAnalog]

Awesome. Thanks for sharing and watching!

[@hipidipi20157max]

What speakers would be best for this amp? Would Polk T15 or Micca MB42 be right. Can the sub output be used for a center channel?

[@mikew8189]

The SMSL A50 Pro looks pretty neat. Kinda wish they skipped the subwoofer stuff and just gave us regular RCA input jacks though, you know, for those of us who don't need the extra bass boom. Also I think SMSL can do better ( make more intuitive ) on their menu screen system.

[@ForeverAnalog]

Agreed. Thanks for watching and commenting!

[@johanakerblad339]

They use a low output impedance IC MA12070 that can drive any other input by making a simple adapter. Also some subs comes with speaker input. Actually the SMSL choice is fantastic. You can choose direct to speaker or make a very simple adapter. Will test when my A50 Pro comes tommorrow if transport works Ok.

[@Douglas_Blake_579]

Hello Aaron ... A couple of things ... First: The 3.5mm trs input is neither better nor worse than RCA connections. It is just a different connector. With a proper cable, both are equally well shielded and will have the same sonic qualities. According to SMSL's documentation the SW output is summed stereo with Low pass filters and a Sub volume that you can set it to various levels. There are also high pass filters for the L and R speakers. This promises a very interesting setup: If you turn off the filters, you can use the SW out for a full range centre channel speaker. Then, if you have an active sub you can also tap the SW output to feed the high level inputs on an active sub, using the internal SW out level control to manage the centre speaker and the SUB's own gain and filter settings to balance the sound. This would let you set up a 3.1 system... L C R . S ... all managed by the main volume control. I haven't had one of these on the bench yet, so I will not comment on sound or specs... but the idea of running a centre speaker at somewhat reduced volume to fill in or blend the soundstage is very attractive. No more "head in a vice" listening (Grin).

[@ForeverAnalog]

Great points as always! Thank you!

[@Douglas_Blake_579]

@@ForeverAnalog I did this on a 2.1 amp for a friend about a year ago. Had to go inside and bypass the filters, but the result was pretty good. It almost looks like SMSL has provided for 3.1 in their design. Strange .... not available in Canada ???

[@johanakerblad339]

Have built the simple adapter and dly is planned for Friday of A50Pro. Could send a picture if you have an emailadress that I can use. Expect to test during weekend

[@Douglas_Blake_579]

@@johanakerblad339 Nope ... not going to send you my email address. But do let me caution you to first do some careful checking on those output binding posts. These may be BTL outputs in which case neither binding post is ground, both are active. Building your little gizmo without considering this could actually damage the amplifier by shorting it's outputs to ground.

[@johanakerblad339]

@@Douglas_Blake_579 Very good advice! Will check this. Will check grounding and impedance and then connect a couple of suitable capacitors on both poles.

[@D1N02]

If your active sub has speaker level inputs you can still use it, but then you don't need the sw speaker level outputs, because you can paass through the right and left channel and the sub will cross it over for you..... Fosi also did this recently. Maybe passive subs are a thing in asia because they are a lot cheaper.

[@ForeverAnalog]

Great point, thank you for sharing!

[@jwren51]

My Wharfedale Diamond SW150 has a speaker level input which I think you could connect to the outputs for a passive sub.

[@ForeverAnalog]

Interesting!

[@steveraleigh100]

you can get an RCA to 3.5mm adapter that should work fine in this case.

[@brucesamuelson7541]

I'm using a Fosi BT30 2.1 with a 10" passive sub that's so much better than a sound bar and powered sub!

[@ForeverAnalog]

Awesome!

[@SnapperX3]

You could use the line level inputs on your sub (if your sub comes so equipped.) So, a cheap amp with bass management & high pass.

[@ForeverAnalog]

Great point, thank you!

[@MykeHawke-r9r]

LOL yeah I hate on class DMS too and then I heard one that was like holy s***

[@hipidipi20157max]

I like the clean design and the subwf output, but subwoofers are very expensive, more than a pair of decent speakers

[@johanakerblad339]

Ordered one today. I guess they have one MA12070 driving the sub output. Should be easy to make an adapter to e.g RCA cable. Will check when I get the unit. I plan to put a 5W 8-22ohm dummy load resistor across output terminal and have a 500ohm potentiometer in parallel to adjust outputlevel to my KEF KC62 sub. In my 30m2 room I rarely reach 2W outputpower. My speakers have appr. 87dB rating for 1W input.

[@ForeverAnalog]

Awesome. Thanks for sharing! Would love to know your experience when it arrives!

[@johanakerblad339]

@@ForeverAnalog Asked SMSL and they confirmed I was right. Fantastic support! Please find copy below. If you want a picture of my adapter, please give an official email adress. Copy: Hello, First of all, your description is correct. One chip is used for L/R channels, and the other chip is used for subwoofer channel. Regarding whether it can be connected to KC62. According to what I know, KC62 does have a speaker input. But the interface of this input is not a standard 4mm banana interface. If KC62 comes with an adapter for connection. Then you can connect the SW output of A50PRO to one of the channels of KC62's speaker input and use it normally. (It doesn't matter whether you choose L or R. My understanding is that the L/R signals will also be combined after entering the KC62.) End copy

[@johanakerblad339]

I asked KEF KC62 if I could connect their speaker input to bridged or single ended amp and they confirmed that this unit was Ok for both. Please find copy below: I received a response from our engineering team and you should be able to use the KC62 safely with single-ended or bridged output stages. End copy. By this I do not need any special adapter.

[@bullwinklemoose7232]

Pro and Con Pros Inexpensive PORTABLE! I can power it directly from an Anker 537 power bank and still have remote control Sounds really good for the price We can ignore the sub output and just use it as a stereo amp They seem to have fixed the issue they had on another small amp (DA-6) where the Amp would be destroyed if you plug the power in while the amp was on (seems very reliable so far) Cons SBC Bluetooth ONLY! (Give me more codec options / AptX and AAC) I'd like a line level output too That 3D stereo width tweak they have on the AO100 would be awesome as well (it sounds great on small near-field desktop speakers) I would pay $100 to $120 if they would fix those 3 Cons on the next version

[@ForeverAnalog]

Thank you for the feedback and for watching!

[@glitch10]

SBC was a real let down indeed, you lose like 20% of body with voice, also I can't get 24bit audio through USB with phone anymore with this amp, normal USB type c to c isn't recognized with phone, I have to use a double dongle which is C>A then A>C to get working.

[@bullwinklemoose7232]

@@glitch10 Anymore? As in........ it used to work? Wrong USB C cable ? Wrong settings on phone ? The USB C input on the Amp is basically USB Audio Class 1 ( or SPDIF over USB ) It works without drivers even on computers that do not support USB Audio Class 2 It works fine even with Windows XP-SP2 on my Sandy Bridge Computers and should work with any game consoles as well. Windows XP-SP2 can play 24 bit - 192 Khz fine over USB A to C cable or over optical cable In other versions of Windows or Linux, the output bit rate and sample rate to the Amp is set by the operating system separately from the actual bit rate of the Audio file I can play 24 bit / 32 bit and even 64 bit float audio files as long as the final bit rate is set to 16 or 24 bits at the O.S. level Google: "Aul Converter" to see how you can convert audio files up to 768 Khz / 64 bit float for testing Audio Equipment The USB input should just work without drivers or software support on basically anything

[@glitch10]

@@bullwinklemoose7232my phone is Samsung and I've been capable of just using a cable to connect previous amp, with this I need to use dongle or adapter or it would just wouldn't detect through phone speakers, I just tested fiio M11 and type C to C worked just fine but still locked to 16 bit 44.1 KHz, maybe it's an android issue? I plugged it into fire cube and it worked just fine.

[@glitch10]

@@bullwinklemoose7232 BTW when I said normal USB I meant without any additional attachments like adapter/dongle, I got 3 cables and 2 are from OEM so I find it hard to believe the cables are the problem also on PC I'm getting 16 bit.

[@МаксимНагорный-м2г]

tell me whether this sound amplifier is suitable for Sony Core SS-CS5

[@ForeverAnalog]

Hi there, I haven't used these speakers before, so I can't speak to how they would pair. Spec wise, the Sony's are 87db and I bet the A50 Pro could power those fine, but again, I do not have the first hand experience to say for sure.

[@Doronyoutube]

I've got that setup right now and it works great.

[@Gafortiby]

I am also baffled by the passive sub outputs. Even at Goodwill, all the subs are active. :D Another weird (possibly good?) technical choice is using the MA12070P chipset which only takes digital input signals. The upside is that digital signals don’t go through a separate DAC. But analog inputs must be going through an unspecified ADC inside before it gets amplified through the MA12070P chip. For your future reviews, can you cover more details about the sound quality? How is the noise floor? Is the noise floor different for each input?-Some budget amps have different sound quality depending on input choice, and I suspect this one might have very different sonics between digital and analog inputs.

[@ForeverAnalog]

Great points, thank you. And great idea on the sound quality details, thank you!

[@bullwinklemoose7232]

The "unspecified" ADC sounds great and I cannot tell the difference between Analog and Digital Inputs The noise floor is lower than SMSL's 1st gen Infineon Amps and is not a problem SMSL also has a very good track record of rejecting any and all audible ground loop noise from computers with cheap power supplies I keep one of those "free" power supplies that come with cheap computer cases just for testing DAC's and AMP's noise rejection That power supply is the noisiest piece of C&^% I have ever heard, and ALL midrange SMSL products reject the audible noise from it Only the cheapest SMSL DAC I have cost around $12 has a problem with noise rejection That DAC is very old and I don't think they sell it anymore I have not tested the noise floor difference between Analog and Digital Inputs and do not foresee it being a problem unless the Analog source has a noise problem If the source is the problem, then replace the source The Amp will not be the problem!

[@ForeverAnalog]

@bullwinklemoose7232 thanks for sharing your experience!

[@crazyprayingmantis5596]

These chi fi companies need to make straigt plain amplifiers with no volume control and then make a matching tube pre with multiple inputs, vu meters to pair with

[@bullwinklemoose7232]

Digital Volume Control at the Amp is great, I'd keep the Volume control and drop all the EQ adjustments The digital EQ's on my computers are vastly more capable than this Amp's EQ If you want VU meters, then you can get them right now for an extra $180 The SMSL A200 Amp has the EXACT SAME SPECS as this A50 Pro (Read the Spec sheet) So, for the price of 3 - A50 Pro's, you can get the same sound quality with VU meters The A200 is only 2 channels (Pay more / get less)

[@crazyprayingmantis5596]

@@bullwinklemoose7232 You don't seem to understand what I'm saying. They should make "dumb" class D amplifiers and a matching Tube pre amp with enough inputs to satisfy everyone's needs, a sub output with low pass filter would be nice 2. 2 seperate components A tube pre (the brains) A stereo amp (the brawn)

[@matthewhilty4209]

Not on topic but I like your thumbnail. If I see a creator with overreacting funny face click bait, I sometimes just skip the video.

[@ForeverAnalog]

Thank you. It sounds silly but the thumbnail design is often the hardest part for me.

[@matthewhilty4209]

Wouldn't this be awesome for a gaming setup ? Most powered speakers don't have an HDMI and usb sometimes causes latency. Grab some KEF 150s and this might be a rockin gamer setup.

[@ForeverAnalog]

I bet so! All of my gaming consoles left when my sons moved out for college so I didn’t think of that lol. Thanks for the great idea!

[@jim010109]

I like the new graphics on your video format. Honestly in this day and age I didnt realize anybody made passive subs. I figured they were all powered.

[@ForeverAnalog]

Thank you! I feel like the graphics help me organize the overall presentation better. Sometimes there so much info to pass along that I worry people’s eyes start to cross lol.

[@sidesup8286]

I really have never had the occasion to listen to these small modern Class D amps, so I won't be stupid, like some people and comment about things I am not familiar with. But the one thing I would bet with total inexperience with them; is that they will sound ridiculously miniaturized, compared to bigger vintage amps with big transformers. In my very vast experience, amps with huge transformers, always without exception, have hige instrument size. A grand piano sounds like it is believably in your room, and matches the actual size of a real grand piano.Going to an amp with a smaller transformer, and the piano isn't believable anymore, as it's apparent size is too small to be convincing and believable.Also big transformers tend to have more beefy bass and faster transient response. Of the many dozens of amps I've heard this unfailingly always seems to be the case. Even if everything else sounds absolutely perfect, instruments that sound too small just don't have realism. Unless you've never heard the instrument in real life. In my mods I have come up with ways to make an amp sound like it has a bigger transformer, but there is a limit, and in my opinion there is really no substitute for a big beefy transformer. Maybe Class D amps would be ideal with one of these super tower speakers which have a line source of 8 midranges and 12 tweeters. Thick high end cables can also give a perceived bigger image size, but not near as much as football sixed transformers.

[@Douglas_Blake_579]

What in the haitch eee double hockey sticks are you on about? There are no transformers in any of these small amps. They use external switching power supplies for the express reason of getting rid of the big stupid transformers.

[@sidesup8286]

The very first thing I said was that I was not too familiar with these amps. So I DIDN'T SAY they had small transformers; or any transformers, for that matter. Another wreckless inference on your part again. I hear the high end cable industry is up 40% in the first two quarters.

[@Douglas_Blake_579]

@@sidesup8286 Just getting a little tired of you constantly claiming greatness within a sea of gibberish. You have literally no clue what you are talking about and it shows.

[@sidesup8286]

Re: your nasty comment. You are just an old man with nothing stimulating in your life that makes you feel alive. So you troll the internet looking for arguments, as even negative stimulation is better than none. You are obviously jealous as many have said to you on numerous occasions and on numerous audio channels. You have never had the magical qualities that we hear in droves, every time we turn our stereos on. The cheaper stuff you listen on, simply doesn't have those qualities. On the equipment you've owned, you've never had true air volume reproduced as instruments have in real life; you've only had sound that sounds closed in and canned. A Small miniaturized depiction of the instruments which would not fool anyone, even a child like yourself, into thinking it is real. You've never had transparency to the degree that you hear every subtlety and nuance. You've never had sound so clean that it is velvety smooth. You'd have to turn your treble control back to morning hours (9 o' clock or something), to hear anywhere near smoothness like that.But then you"d lack treble. You've never had a system where there are wide open canyons of space and air between instruments; only what sounds like instruments standing on the backs of other instruments like an incredibly crowded elevator, or audio traffic jam... So don't pretend we are all crazy, for the special qualities that we DO have, and you don't. 99% of the people whose systems do have these very enjoyable qualities are sane enough and lead sane enough lives, that they don't spend their time being internet trolls looking for arguments for virtually their only stimulation in life.

[@sidesup8286]

My goal isn't to know every technical detail. My goal has been to achieve a degree of sonic realism from recordings that doesn't require too big a stretch of the imagination to think you're listening to real live performers in your listening room. Live music is a tough standard. I have achieved what I dreamed of. You can enjoy all the facts; I like to enjoy the music and bring it to life as few have ever heard it before since the original recording session in the studio; be it 1986 or 1968.