THIS is what happens when Fosi listens to what we WANT! - Fosi ZA3 Review

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Finally a mini amplifier company is listening to us. The Fosi ZA3 review shows just that. Fosi includes balanced inputs, variable subwoofer out and replaceable Op amps making the Fosi ZA3 a very powerful mini amp. Add in the fact it can switch to a mono amplifier with the flip of a switch to give you 235 watts of power! This might just be the best mini amplifier on the market.
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[@ineedtocreatethat4468]

Great overview as always. I actually purchased 2 Fosi Audio BT20A’s for use as Atmos channel amps earlier this year. I still need to build the speakers, I have high hopes that they will work out for my needs. If not the Fosi ZA3 looks like it would be a great alternative.

[@mcjonner]

This combined with a wiim pro+ would be awesome with a remote and eq and decent dac.

[@veeclash4157]

This amplifier looks really good! I also like the design choices. Now where's our matching DAC?

[@AdamsOlympia]

Love this amp so far! Cleanly and effortlessly drives my new KEF q150, with plenty of headroom to spare. I'm currently feeding the ZA3 with an RME Babyface Pro FS interface, planning to send headphone out directly to an SVS sub when it arrives, and a high-passed main out to ZA3 (using RME's built in EQ) . Do you think that'll work about as well as having dedicated crossovers? I don't have a lot of HiFi experience, as it's my first stereo in ages.

[@danrussell9357]

Liked the video! This model seems to be the Fosi heavy hitter with more power from the 48v PS and mono setting. A lot of sound bars have rca outs for extra speakers. I could see this amp used to power those channels and even add a sub out line for a sound bar.

[@Toid]

Thanks! Those are good ideas as well. Honestly it’s just a great amplifier as long as you’re using a preamp or don’t have any need for a dac or Bluetooth input.

[@danrussell9357]

I bought a Fosi 3255 amp a little while ago for a projector in a classroom. This amp would be a great choice for that application especially if you could add a sub.

[@MrBenherrmann]

Thanks for the video. Fosi just keeps making these things better and better. I upgraded the Op-Amps in my ZA3 to the Sparkos Labs versions and the sound tonality differences were quite noticeable - read, "expanded, more spatial sound-staging and a smoother class AB-like sound." Now I must add that the ZA3's personality changes with different speakers. On some speakers, it can come across as too cool and clinical, whereas with others, it shines! My KEF speakers love this ZA3 - especially in balanced mode. However, my Wharfedale models pass along music from the ZA3 that is much cooler - now go figure?

[@AdamsOlympia]

I can vouch for that! I briefly tested a Cambridge CXA81 A/B amp with Kef Q350s before I settled on my ZA3 + q150s .. Sounds every bit as big and warm to me -- not at all flat, harsh and clinical like my Adam A7X powered monitors. Incredible pairing! I'm so in awe of the KEF sound, I'll probably inevitably upgrade to either q950 or LS50s in the next year or two.. Maybe FOSI will release their planned monoblocks by then.

[@thomasw1496]

Aren't wharfedales known for their silky smooth and a bit warmer sound?I'm surprised that you say they sound a bit cooler with the ZA3. I would have expected them to sound pleasant, warm and non clinical. I thought about using the ZA3 with Wharfedales 12.0...

[@MrBenherrmann]

@@thomasw1496 Not every Wharfedale speaker has that silky smooth sound - in fact, some can be a bit bright to begin with.

[@thomasw1496]

@@MrBenherrmann Ah good to know! Then it makes sense, thanks for clarification

[@cosmiccharlie8294]

I'll be pushing mine with a Emotiva BasX PT2 Pre amp, hope that goes well.

[@tom6363]

I am planning on using this to power my rear surrounds and connecting to my receiver with the trigger in. Will I need to just leave the unit's power on all the time or does it have a standby mode?

[@lehsu]

How about a 3.1 setup? Is there a DAC that can take hdmi ARC from a TV and process 3 xlr out? One for center channel, one for R anc one for L?

[@mikecees2230]

Hi, good video, also enjoyed your Starkrimson build video. I just received a ZA3 that I find quite surprising for the price. Fosi offer a 48V GaN PSU, I was wondering if you have any thoughts about how it compares to the regular 48V PSU. Thanks

[@Toid]

I haven’t used it, so I really can’t give any thoughts on it. But I would be interested to hear your opinion if you do get it.

[@mikecees2230]

@@Toid I had ordered one with the ZA3 but they sent me the regular 48V PSU instead. If I read enough really positive comments on the GaN I might be tempted to order one but for now I'll stick with what I've got. I got this mostly out of curiosity so I don't want to go crazy with upgrades (discrete op amps, etc) that will add up to the price of a full featured integrated.

[@noahblorm2990]

Great review! Do you know what the crossover (LPF) may be for the sub out if there is one at all? Two of these might finally allow me to have true left and right separated subwoofer output instead of mixing both L and R into both subs.

[@mattburgess2]

The sub out is 20hz -- 300hz as stated by fosi

[@noahblorm2990]

Thanks!@@mattburgess2

[@lehsu]

If I set this up as 2.1 or 3.1, which channel, L , R or Center(if used) should I connect the SUB?

[@mcjonner]

I read the next iteration of this will have a high pass filter!! Cross fingers

[@JMJM75257]

High frequencies requires a really high quality capacitor. If they give you a high pass but with a cheap electrolytic it will greatly affect sound quality and not worth it imo. You can make your own 1st order high pass using a high quality capacitor inline with each RCA. Gr research does a video on it that could help you. I use miflex kcpu caps . This is an example of an actual high quality capacitor. In comparison low passes are way easier as below 100hz or so capacitor quality doesn't affect sound as much. Hope this helps.

[@AdamsOlympia]

@@JMJM75257 Would you be better off just EQing in the digital realm? I'm planning to use my Babyface Pro's built in EQ to highpass the XLR output to ZA3 and send a full spectrum output from Babyface to an SVS Sub when it arrives, using the subs built in LPF and leaving the ZA3's sub output unused. Might even remove the sub output opamps to reduce idle power consumption.

[@alexw890]

All that’s missing is a switchable 80hz high pass like the RSL amp has. That’s a key feature in my opinion.

[@Toid]

You know, I meant to mention that there was no highpass on the speakers. I do agree a defeatable high pass would have been a nice addition.

[@alexw890]

@@Toidplease put an addendum on your video. Hopefully Fosi will listen. Everyone I’ve said this to agrees.

[@perlman7376]

I need a preamp with multiple inputs (at least 4) and so how would the Schiit Saga S do with this amp? Thanks for any response.

[@Toid]

It would work fine. However, I would personally try to get something with balanced outputs, if I could

[@MrSumancherry]

Does the amp still controls subwoofer out in mono mode ? As well does it has a crossover ?

[@AdamsOlympia]

Sub out gain is indeed controlled with the ZA3's gain attenuation knob. It sends a low passed signal to the sub ...I just wish it had a HPF for the speakers instead, since most subs have a built in LPF

[@95lovi]

How does the fosi za3 compare to the DIY ICE amp from parts express ? Where does one get the better sound per cost ?

[@Toid]

They are a little bit different as far as what type of amplifier they are. But I really like this Fosi. Definitely open my eyes. How good these cheaper amplifiers can be. I still like the DIY ICE amplifier better.

[@mrboat580]

Thank you for the review. These amps still have me buying used AVRs for 2-channel for more stable power into 8Ohms, comprehensive bass management, pre outs etc., in all but portable systems. I always have more room around my desk for larger amps. I have the BT30D Pro and the V3 for travel or for some full range speakers in a small room. I can get a used 120wpc AVR for around $75-100 off ebay or marketplace, some with minimal hours. I was about to pull the trigger on two of these and it occurred to me that it is not really complete. I'm not fooling with anymore of these toys until they get more complete bass management and a real 100wpc/8Ohms. They do perform well and I appreciate what Fosi is offering in the sub $200 price range. When we start asking for more features, they start becoming more expensive.

[@halrichard1969]

I have been shopping hard for an amp to give me something close to 200watts per channel for my desktop monitors, and around 220 watts for each of my Subs. I think a stack of three of these would do the trick. Having a Mini-DSP in front connecting all of them. What do you think, Nick? Oh, if you look inside you can see that they have Plug-ins for the OP Amps. Take you pick.

[@RP-ms7lu]

Get Denon 600NE ,brilliant sound and powerful. Easily drive my q acoustics 3050i towers . Going cheap now. Will beat any fosi etc to dust.

[@veeclash4157]

@@RP-ms7luA $500 amp beats a $150 amp? I'm really not surprised.

[@RP-ms7lu]

In the recent sale it was 300 !​@@veeclash4157

[@d.s.w7779]

Are they realy 180w @4ohm?

[@cpaint69]

How do you setup this amplifier if you are hooking it up with a pre amp? At what volume position do you set on this ZA3 when you use it as a power amp?

[@Toid]

I typically do not go over 3/4 volume.

[@jayem1826]

I’ve read to go all the way up. Just try it

[@joshcatstream]

I've been asking for the budget amp makers to employ some fixes for load dependency, but so far no one has. Any idea if this unit has a fix or is it another load dependent cheap amp? That's really my biggest problem with these amps. When paired with higher than typical HF impedance, the amp will cause a HF rise. The c-note kit is a speaker that does not play well with these, I exhibited a 10db rise from 6k to 15k when paired with an Aiyima A07.

[@alexw890]

I have encountered this as well. It would also be nice to be able to use one channel only for using these amps for crossover design without having to put a load resistor on the empty channel.

[@JMJM75257]

Your right they still haven't implemented the chip as well as even the ti evaluation board. It's a real shame as pffb would really make this a contender to serious amps whereas now it's still a roll of the dice as to whether you'll get excess upper frequencies or a flat response with your specific speakers. Such a shame and why I think this product is abit meh...

[@carlsitler9071]

I can't use an amp that doesn't have a 100 hz crossover for the mains and lows. I have the a07 but only use either my BasX or powered Klipsch.

[@alexw890]

Totally agree. I’ve been saying this in every review for this amp I’ve seen and everyone agrees. I bet you the next version has one. Somewhere 80-100hz switchable high pass!!

[@JMJM75257]

I think 80hz lpf would be preferable. As above this the lows become less omnidirectional. Also if they include a lpf in the future they will need to add a variable phase control, not a simple 0/180 switch that isnt very useful.

[@jimlyall8624]

If it had a remote I'd buy it

[@jamesmansion2572]

So - 48V at 5A is a max output from the PSU of 240W. Where does the extra power come from for those power settings? I think those are probably what the TI chip can do without frying itself, but you would need a bigger power supply than that 48V brick to do it.

[@Toid]

You should check out Williston Audio Labs. He actually tested this and explains why you can get more power out of the power supplies then what’s they are rated. He does a great job on it as well. But I completely understand why you would think that because of the rating on the power supply.

[@paulgood2218]

It does look like a fun little amp

[@YouSoundButtHurt]

what's fun about it?

[@paulgood2218]

@@YouSoundButtHurt it's tunable , scalable , and affordable. What's not fun about it ?

[@iikatinggangsengii2471]

prob competitors offers better accuracy/realistic-ness, final sennheiser susvara lejardin all give more realistic sound, better fun too, technically cheaper options are close or even par with it

[@iikatinggangsengii2471]

its strength is smth hard to explain on reviews, just pleasing/satisfying sound, though i didnt see inaccurate reviews on it

[@thelowprofile9767]

How do you set it up as monoblock considering that it has left and right channel inputs? Do you just use either the red or the white race for input?

[@Toid]

3:55

[@thelowprofile9767]

@@Toid I saw that part but it doesn’t answer the question whether you just select either the right or the left rca input.

[@Toid]

@@thelowprofile9767 I clearly answered it there. I’m not sure what you’re asking if that doesn’t answer it.

[@thelowprofile9767]

@@Toid do you just use the red or the white rca input?

[@KXP70]

​@thelowprofile9767 which of the two is denoted as the 'Right' input?

[@tamayaytam]

So. What are we supposed to do with fosi v3? Toss it?

[@JMJM75257]

Lol nothing wrong with the v3 I didn't make the move to the za3 it's a sidestep not an upgrade. Of course that's if you only require what the v3 has to offer.

[@MattCoykendall1]

Hey Toid!

[@Toid]

Hey Matt! I enjoyed watching your overview of this. You put out three weeks ago. Great video to wet the appetite.

[@MattCoykendall1]

Yeah now I missed the boat haha, might get my review out tomorrow! Thanks for the great review.

[@Toid]

@@MattCoykendall1 lol you were ahead of everyone else. I’m looking forward to your review.

[@andranikoriginalesfahan8798]

❤️‍🔥

[@gibson2623]

If this is a power amp, why the 2 inputs? I wouldn t use this to connect a guitar, surely.

[@RP-ms7lu]

Still no bluetooth!

[@IvanITpro]

3:16 - None of these models have a subwoofer out, they all call it either AUX out or PRE out. It's not their fault people are trying to use it as a subwoofer out, but we sure do expect and want a subwoofer out. Problem solved with ZA3 and they actually have and state it's a subwoofer out.. ;)

[@Toid]

Great point

[@ernestporee3697]

XLRs are a pro touch…if you do any music production you will use XLRs it’s a noisy environment and XLRs help keep that from entering the mix. Also if you have true ! Balanced pre amp , there will be a better sound. And good XLRs are better than overpriced RCAs ! Every recording you ever heard was done via XLRs! It’s funny how people try to post production things that have already been done ? You try to out spend the studio or the artist by buying things to do something that’s been addressed…people’s systems cost more than what the artist was paid to record it ? You could buy 3 ZA3 amps and a Behringer digital crossover and do some interesting things for less money than a pair of overpriced rca’s . Pros get paid to do this…Audiophiles try to buy the stairway to heaven ? These products can open up a whole noo world of possibilities, without bank breaking displays of misplaced ego .

[@richh650]

I like it but the stereo/mono switch should NOT be on the front and so easily accessible. Also, would like to remove the variable volume by them providing a defeat switch that would make it standard output level with no variable volume to mess with each time one turns it on.

[@spritual_enlightenment]

I always thought an independent volume for subwoofer is better.

[@Toid]

This is an RCa out for a powered subwoofer. In this case, you set your subwoofer gain on your subwoofer amplifier. THen when you use the Fosi volume it will turn the subwoofer up and down according to the volume of the amplifier. Basically this subwoofer out reacts the same way a surround sound receiver would react. Not if this had it's own subwoofer out via speaker terminals (aka to hook up a passive subwoofer) then you would want the amplifier to have a subwoofer volume pot.

[@djg6015]

The only problem with the Fosi amps is whether to buy now or wait 6 months for the next, better amp.

[@Toid]

There is a lot of truth to this statement

[@mikecees2230]

That could be said about a lot of audio gear, at least this thing only costs a few bucks.

[@fonkenful]

This little baby is getting a lot of press at the moment, and its hard for an old fart like me to remember what’s been commented on where, but I’ll give my own suggestions for future iterations: - TRS 1/4” jacks for balanced take up less room than the XLR combos, which should allow sufficient extra space for beefier / staggered binding posts on the same chassis size; - relocate the stereo mono switch; - engage an adjustable HP filter function to the internal amp stage when connected to sub; - headphone jack for those so inclined?

[@crazyprayingmantis5596]

But i asked fosi for a low pass filter, a parametric eq and dsp

[@Toid]

You asked for a lot :) On a serious note, you should check out my Arylic B50 review. That might be what you are looking for. kzbin.info/www/bejne/aKayiJVji56Yeas

[@ap5672]

3:41 bro if the sub out wasn't tied to main volume it would be completely useless.

[@Toid]

I completely completely agree. Unfortunately there are a lot of these mini amps where they are not tied together.

[@ap5672]

@Toid wow really. Thanks for that information, I did know.

[@chrislosada6701]

I want to see this actually benchmarked 😉😉

[@Toid]

It would be nice. I need to get a new testing station before I dyno any more amplifiers,

[@chrislosada6701]

@@Toid we can also get a collab with an awesome youtuber you already have a podcast with ;)

[@Toid]

@@chrislosada6701 ha! Good point! I think we are both working on our test benches. I want to made sure I’m getting good clean voltage out of my RCA pre-outs. That way I know I’m trying in the ball park. My main issue was my preout was so weak it wouldn’t push the higher voltage amplifiers like this to their max.

[@chrislosada6701]

@@Toid OHHH, I see, Ive recently been dabbing into the signal voltage world, its been a wild ride. Looking forward to seeing what you have to teach us!

[@JMJM75257]

This is abit of a meh product imo. They could have added pffb, they didnt . They could have added true bridging mono but they didn't, they just use one channel for mono. And they could have shipped stock with gan based psu but they didn't. Feels to me although they added the features they could at the least cost to them possible. Im not knocking them its a decent product at a decent price i had just hoped they would have added pffb at the very least...

[@ts6640]

Yea. I find it very foolish Fosi decided against incorporating “bridging” as a feature.

[@Toid]

I do think true bridging would’ve been nice for the mono output.

[@tigerbalm666]

Who the fuc uses xlr...I've never met anyone who does! I won't buy this since I don't or ever will...

[@Toid]

Of you own a decent preamp it will have the ability for balanced inputs. There are quite a few benefits for going balanced over unbalanced that I’m not going to go over right now, but you’re welcome to look up if you’re interested.

[@rakitakhan]

An amp of this quality has zero need for balanced inputs. The difference MIGHT be measurable, but there's no way you'll hear it.

[@mikecees2230]

I agree... unless you need to run long interconnects or wish to connect 2 sources. I could picture one of these near L&R speakers in dual mono hooked up to a pre-amp at the other end of a listening space.

[@deckers222]

D better than AB.

[@DA-jw6nm]

your entire summation of this "sound" device is that it sounds neutral. that's it? don't know how you got 87k subs.

[@dustinstorey6779]

Ok so I want to know how this compares to the WiiM amp pro plus and the SMSL AL200. . I get that this isn’t a streamer and you would need a preamp to control the input signal. But as far as quality goes are these same basic level. All three of these seem popular and highly rated , I just want to know the use case for each.

[@Toid]

There are completely different. The Fosi offers the most power and the ability to add unbalanced inputs. The Wii is a steamer with a DAC. Finally the SMSL is an integrated amplifier with various inputs. I’d get the SMSL if I didn’t have a preempt or didn’t want to get one. And I would get the Fosi if I just wanted to amplifier with the benefit of balanced inputs. And obviously I’d get the Wiim if I wanted a streamer.