Fosi Audio ZA3 Amplifier Review

[doug s.]

That's brilliant and just what I'm looking for as The Mrs doesn't like the size my current system takes up so any oppotunity to get something smaller is only going to win me some brownie points .... I'm assuming you currently own a ZA3 and have back to backed them against what you currently have?

You also use the plural of saying AMPS rather than just one .... how many AMPS do you currently own costing several thousand dollars that sound better than this .... can you list them please including how you tested them, as much as anything might help anyone avoid buying them in the future.

Some pictures of the ZA3 next to your other AMPS would be brilliant as well, I'd help us all put some scale into the scenario, I think there'd be a huge audience for an amp that size and cost that sounds as good or better than amps costing so much more and keeps the significant other happy ... especially at the cost, less than a pair of Jimmy Choos ... that'll stop her nagging I spend too much on HiFi

if you re-read my prior post that you replied to, you will notice it's the aiyima a07 max's that i own. while some have noted differences between the two, i find it hard to imagine the differences could be that great, but again, i have not heard the fosi amps myself.

and, when i reference more expensive amps, i was referring to a youtube video where the designer of qualio and cube audio speakers prefers a pair of za3's to a $5k naim integrated to drive his €6.900,00 qualio iq speakers. in the same video, he also speaks favorably of the earlier aiyima a07, and mentions one of his uk buddies that prefers the a07 max to his vitus amp; he didn't say which one; only that it was €10,000. i checked the vitus price list; as of 2021; the least expensive amp on their list showed €13k.

regarding my own amps, i have a pass f2 clone, which is pretty inexpensive, but if it were one of the 100 nelson made, it would have cost $3k. i also was using an almarro a205a mkii, w/upgraded caps. it retailed for only $800, 20 years ago, but they typically sell for at least that today when stock. i also used a mesa baron, which retailed for $4000-$4500 25 years ago, depending on tubes, and typically sells for about that today, if you can find one. when it was reviewed in the '90's, it was considered a bargain at the price.

having heard good things about these 3255 amps, and seeing their extremely low prices, i figured what the hell - i just wanted to reduce the idle draw to 6w for each amp, instead of the ~300w the almarro and the f2 clone were drawing. if the sound was even as good, i'd be happy. and, as it turns out it is at least as good, even a little better, imo. and i put some discrete class-a op amps in the one driving my full range driver from 175hz-7khz, and it got even better. the other amp i left stock, because all it's doing is driving ribbon tweeters >7khz, and i didn't think it was worth it. i had to fab a case for the op-amps as they didn't fit; if they did fit, i'd have gone ahead and installed them, as i bought a pair for each amp. so, i'm a happy camper. my system, btw, is actively quad-amped - subs below 80hz, midbass from 80hz-175hz, full range drivers in oris horns from 175hz-7khz, and the ribbon tweets >7khz.

the aiyimas; a lot more room on the top shelf then when the f2 clone and almarro were there; and they're relatively petite in their own right.

system:

doug s.

 

[doug s.]

I think because better performance in SINAD and ZA3 has sub crossover out of the box.

i can understand that, if you want to run a single sub, and you don't care that your main speakers are hi-passed, the za3 would have some appeal. but they may as well just have made the sub out run full range, as almost everyone who uses it will be sending a signal to a powered sub with its own x-over.

in a main system, where you're wanting to hi-pass your main speakers, and run a pair of subs, the sub out doesn't mean much. different use; i'm sure most of these will be used in secondary systems, where s/q is not the primary focus. now, if fosi had initiated a hi-pass on the speaker outs when the sub was engaged, it would become a bit more interesting for those interested in a main system use, w/o having to invest in an outboard x-over. buy two of these amps and you could run stereo subs and hi-pass your mains...

but 88 sinad vs 86 sinad as a reason to choose the fosi? i have to laugh at that one!

doug s.

 

[Fosi Audio]

if fosi had initiated a hi-pass on the speaker outs when the sub was engaged, it would become a bit more interesting for those interested in a main system use

Thanks to members' feedback, our R&D team is currently exploring the feasibility of incorporating adjustable HPF and LPF slide/dip switches. Let's see if we can do something.

 

[Bruce Morgen]

but 88 sinad vs 86 sinad as a reason to choose the fosi? i have to laugh at that one!

Me too. SINAD is good to know, but the "SINAD uber alles" faction tends to ignore the use case factor(s) that more often than not make paying for sky-high SINAD a waste of money better spent on speakers, room treatment, etc.

 

[Omartian]

Debating on this and the RSL ia255.1. Using it for a nearfield PC desktop w/a schiit hel as the DAC and philharmonic true mini speakers and a svs sb1000pro sub. Im leaning RSL bc of the high pass filter? Anyone have any insight on the two?

 

[doug s.]

Thanks to members' feedback, our R&D team is currently exploring the feasibility of incorporating adjustable HPF and LPF slide/dip switches. Let's see if we can do something.

if you can do only one, do the hpf; the lpf is honestly going to be wasted for almost everyone, because who's going to use an outboard amp and passive sub with this?

my opinion, of course!

doug s.

 

[doug s.]

Debating on this and the RSL ia255.1. Using it for a nearfield PC desktop w/a schiit hel as the DAC and philharmonic true mini speakers and a svs sb1000pro sub. Im leaning RSL bc of the high pass filter? Anyone have any insight on the two?

do you mean you're leaning rsl? the svs doesn't have a hi pass out, and you'd need main inputs to feed it to either amp even if it did have it. never mind; i see you edited your post. i certainly have no experience w/the rsl amp. its hi pass feature is certainly nice, but nearfield desktop use may not matter much, either way. it seems you're going to have to get feedback from those who've listened to that amp. like from this thread - 1st page is comments from someone who owns it and the fosi v3:
https://www.audiosciencereview.com/...lass-d-integrated-amplifier-discussion.46256/
(i now see you've already seen the thread, heh!)

doug s.

 

[Omartian]

do you mean you're leaning rsl? the svs doesn't have a hi pass out, and you'd need main inputs to feed it to either amp even if it did have it. never mind; i see you edited your post. i certainly have no experience w/the rsl amp. its hi pass feature is certainly nice, but nearfield desktop use may not matter much, either way. it seems you're going to have to get feedback from those who've listened to that amp. like from this thread - 1st page is comments from someone who owns it and the fosi v3:
https://www.audiosciencereview.com/...lass-d-integrated-amplifier-discussion.46256/

doug s.

Thanks. I posted on that thread as well. Thought the za3 was a big step up from the v3. Hoping I can get someone to weigh in.

 

[doug s.]

Thanks. I posted on that thread as well. Thought the za3 was a big step up from the v3. Hoping I can get someone to weigh in.

actually, from what i can make of it, the v3 is a better amp. whether or not it's sonically better is another thing - the differences are probably quite small, if any. the za3 has a nicer case, and a couple extra features that may or may not be useful. probably its sub out being controlled by the volume pot is the most useful, imo. unfortunately, the v3's pre out is not controlled by its volume pot, which means that, if you were to connect a sub to it, you'd be having to adjust its volume pot separately from the v3's volume pot. for nearfield desktop use, and wanting to connect a sub, w/o hearing any of them, i'd just buy the v3, because i imagine you won't be futzing w/the volume that frequently. but if that's an issue, buy the rsl.

doug s.

 

[staticV3]

unfortunately, its pre out is not controlled by its volume pot, which means that, if you were to connect a sub to it, you'd be having to adjust its volume pot separately from the v3's volume pot.

So, like, Fosi did release a 2024 version of the V3 with proper pre out, but I have no idea what happened to it.

The 2024 Version Fosi Audio V3

Following your valuable suggestions, we've enhanced the Pre-Out circuit. In the 2024 version, it's no longer a simple pass-through interface; instead, it's controlled by the V3's power switch and volume.

fosiaudio.com

 

[lazerharp]

if you re-read my prior post that you replied to, you will notice it's the aiyima a07 max's that i own. while some have noted differences between the two, i find it hard to imagine the differences could be that great, but again, i have not heard the fosi amps myself.

and, when i reference more expensive amps, i was referring to a youtube video where the designer of qualio and cube audio speakers prefers a pair of za3's to a $5k naim integrated to drive his €6.900,00 qualio iq speakers. in the same video, he also speaks favorably of the earlier aiyima a07, and mentions one of his uk buddies that prefers the a07 max to his vitus amp; he didn't say which one; only that it was €10,000. i checked the vitus price list; as of 2021; the least expensive amp on their list showed €13k.

regarding my own amps, i have a pass f2 clone, which is pretty inexpensive, but if it were one of the 100 nelson made, it would have cost $3k. i also was using an almarro a205a mkii, w/upgraded caps. it retailed for only $800, 20 years ago, but they typically sell for at least that today when stock. i also used a mesa baron, which retailed for $4000-$4500 25 years ago, depending on tubes, and typically sells for about that today, if you can find one. when it was reviewed in the '90's, it was considered a bargain at the price.

having heard good things about these 3255 amps, and seeing their extremely low prices, i figured what the hell - i just wanted to reduce the idle draw to 6w for each amp, instead of the ~300w the almarro and the f2 clone were drawing. if the sound was even as good, i'd be happy. and, as it turns out it is at least as good, even a little better, imo. and i put some discrete class-a op amps in the one driving my full range driver from 175hz-7khz, and it got even better. the other amp i left stock, because all it's doing is driving ribbon tweeters >7khz, and i didn't think it was worth it. i had to fab a case for the op-amps as they didn't fit; if they did fit, i'd have gone ahead and installed them, as i bought a pair for each amp. so, i'm a happy camper. my system, btw, is actively quad-amped - subs below 80hz, midbass from 80hz-175hz, full range drivers in oris horns from 175hz-7khz, and the ribbon tweets >7khz.

the aiyimas; a lot more room on the top shelf then when the f2 clone and almarro were there; and they're relatively petite in their own right.
View attachment 351828
system:
View attachment 351827

doug s.

As I wrote in another thread. I had a Naim setup in excellent condition with Preamp, power amp and special PSU for it. When purchased a couple of years ago it retailed for 8000€. I really loved the system.

Then I bought a ZA3 for my office and was very happy with it and one day a put it in my main system and I was Shocked. It sounded better in many areas. The midrange and the warmth off the Naim is hard to beat. After some consideration I sold my Naim set up and bought two ZA3. I have been running it for a couple of week and I love it. As I sold the old equipment I have lots of money left to continue to buy and try new equipment. Whatever people are saying I am sure that the industry gonna change. I don´t say that the ZA3 is perfect but for the money it´s insane. I am really looking forward to see what´s gonna happen with this incredible fast evolution

As the new setup is smaller and much lighter and it´s easier to move around.

New system:

Old system without same DAC as above

 

[Deleted member 48726]

one day a put it in my main system and I was Shocked. It sounded better in most areas.

Alrighty then.

 

[Witterings]

and, when i reference more expensive amps, i was referring to a youtube video where the designer of qualio and cube audio speakers prefers a pair of za3's to a $5k naim integrated to drive his €6.900,00 qualio iq speakers. in the same video, he also speaks favorably of the earlier aiyima a07, and mentions one of his uk buddies that prefers the a07 max to his vitus amp; he didn't say which one; only that it was €10,000. i checked the vitus price list; as of 2021; the least expensive amp on their list showed €13k.

So you haven't actually got one yourself but can professs on how they sound on the back of a "youtube influencer" who if he goes with the flow will get very few hits and make very little money ..... come out and make a big outspoken statement that might seem to be contrarian and loads of people read your reviews and you make lots of money out of it ..... much like there were journalists visiting the quiet areas of hospitals and filming during Covid and saying it didn't exist and it was a goverment conspiracy theory ..... why to get lots of hits and make a name and money for themselves.

Just for info I have a ZA3 and have been back to backing it with an Armam SA30 .... needless to say whilst the ZA3 is an absolutely amazing bang for the buck and I wouldn't hesitate in having one in a secondary listening area .... my Arcam's staying exactly where it is.

 

[iLoveCats]

If anyone cares I finally got the Burr Brown OPA2604 op amps.

They went from New york to San jose and then to me, thanks post office.

My immediate subjective reaction is they sound 'voicey' I use the system (2.1 channel) primarily for TV and there's improvement in dialogue clarity. I wasn't expecting that. It was just the input I had on first. Music sounds good, it's different, I can't really say anything distinct. Nothing jumped out, it's just a different flavor of good.

I'll keep the OPA2604 in.

 

[m0nsieur]

You'll get 15% every time.

doug s.

I eventually got 20% after trying for a couple of weeks. For reference, this was mid-January.

Still trying to decide if I like the sound of it vs my old AB stereo receiver (which most likely has worse SINAD). I'm a little spooked about the ZA3 load dependency findings, given that my speakers have some peaky frequency vs impedance, but I haven't made any measurements yet to reinforce or pacify that small fear.

 

[doug s.]

So you haven't actually got one yourself but can professs on how they sound on the back of a "youtube influencer" who if he goes with the flow will get very few hits and make very little money ..... come out and make a big outspoken statement that might seem to be contrarian and loads of people read your reviews and you make lots of money out of it ..... much like there were journalists visiting the quiet areas of hospitals and filming during Covid and saying it didn't exist and it was a goverment conspiracy theory ..... why to get lots of hits and make a name and money for themselves.

Just for info I have a ZA3 and have been back to backing it with an Armam SA30 .... needless to say whilst the ZA3 is an absolutely amazing bang for the buck and I wouldn't hesitate in having one in a secondary listening area .... my Arcam's staying exactly where it is.

i got the aiyima a07 max's, as their functionality suited my needs better. and yes, i like them more than my mesa baron, cap-upgraded almarro a205a mkii and pass f2 clone.

re: this "youtube influencer", as you call him, he's the designer of high end speakers, and he prefers the fosi and aiyima amps to much more expensive gear he was using to drive his speakers. and he now demos his speakers at audio shows with these amps. he's trying to sell his speakers, not inexpensive amps.

glad you enjoy your arcam more than the za3.

doug s.

 

[nvidia_7]

Anyone else have this happen? First time using it today, plugged in my RCA, and the connector just fell out.

 

[doug s.]

Anyone else have this happen? First time using it today, plugged in my RCA, and the connector just fell out. View attachment 352081

not on this amp, (i don't own one), but i've had this happen on other gear. you should be able to plug it back in. did it come out w/an rca connector being removed?

doug s.

 

[nvidia_7]

not on this amp, (i don't own one), but i've had this happen on other gear. you should be able to plug it back in. did it come out w/an rca connector being removed?

doug s.

It was not removed out of the box. I plugged my RCA cable into it, and the moment I moved the amp back it just fell right out. It doesnt look like there is any solder or anything on the connector. Not sure if there is supposed to be or not, but it doesnt stay in when I put it back in. The other RCA connector is tight and secure.

 

[doug s.]

It was not removed out of the box. I plugged my RCA cable into it, and the moment I moved the amp back it just fell right out. It doesnt look like there is any solder or anything on the connector. Not sure if there is supposed to be or not, but it doesnt stay in when I put it back in. The other RCA connector is tight and secure.

it could be the plastic inside is broken, and not holding the little 'teeth". may be time to return it for a replacement. i don't see the red plastic piece; should be there, just like the white one above it...

doug s.