Fosi Audio's First Dual-Mode Balanced Amplifier ZA3

[Idrago]

Hi friend, this short video was recorded to demonstrate that we can use two ZA3s in mono mode to build a real stereo system-one ZA3 for each channel.

There is a power advantage actually(due to PSU limitation, maybe it's not as significant as expected). Pls refer to this rated power we measured without exaggeration

ZA3 will probably be the flagship in the next period, you have checks made for the 48V 10A power supply, the power rate in mono and stereo mode, thank you.

 

[TonyJZX]

aiyima were also using a similar power chart

they made claims about 10-12 amps but these arent available from them nor would this be advisable? do these guys even warrant above 48v 5a?

to me these power figures are about right for the 3255

95w at 1hz 1% thd

the old A07 tested at 89w in the real world

the newer A07 Max went to 70w

and so one might surmise the ZA3 would do 75w in the real world? maybe 80w? still good

 

[John4949]

Hello, I am considering buying two Fosi Za3s for the end of the year to do dual mono mode. I already have an Aiyima A07 that I modified a little (replacing the AOPs with two SPARKOS LABS SS3602 + changing the 4 inductors + red WIMA capacitors - the sound has improved a lot compared to the original version). Regarding the new model from Fosi, the ZA3, I was wondering if I could use the MEAN WELL LRS-350-36 Switching Power Supply Module SMPS 36V 9.7A 350W power supplies, I can't find anything regarding this voltage and amperage: 36V -- 9.7A. Do you think my Mean Well power supplies could damage the ZA3s because they would be too powerful for two amps in mono mode?? In advance, thank you, see you later.

 

[Guddu]

Hello, I am considering buying two Fosi Za3s for the end of the year to do dual mono mode. I already have an Aiyima A07 that I modified a little (replacing the AOPs with two SPARKOS LABS SS3602 + changing the 4 inductors + red WIMA capacitors - the sound has improved a lot compared to the original version). Regarding the new model from Fosi, the ZA3, I was wondering if I could use the MEAN WELL LRS-350-36 Switching Power Supply Module SMPS 36V 9.7A 350W power supplies, I can't find anything regarding this voltage and amperage: 36V -- 9.7A. Do you think my Mean Well power supplies could damage the ZA3s because they would be too powerful for two amps in mono mode?? In advance, thank you, see you later.

32v - 48v psu will be fine, normally you would get 10a max psu which is fine.
ZA3 comes with 48v 5a psu already, why would you want to go for 36v?

 

[K.Kevin]

I’m trying to decide whether it would be worth getting a ZA3 for mono functionality or if a Fosi V3 driving just a single speaker would suffice?

Background: I was going to get one A07 Max for the Center speaker, because of its bridged function. However, after Amirs review, I put that plan on pause. I noticed it doesn’t actually provide significantly more power in bridged mono than when driving 2 channels, only a modest 10-20% bump. And those stereo power output measurements are also not in and of themselves much higher than what the Fosi V3 can already provide in stereo anyways.

Question: do you think the Fosi v3 would experience the same type of small 10-20% bump in power output if I only drove my single center speaker from them? Even though it lacks any bridged “switch”? Because I think that would be sufficient power, and then it wouldn’t make sense to wait for the ZA3 and pay more for it too

I know in AVR measurements, which are usually class A/B, the power output drops as you add more and more channels. I’m wondering if that same principle applies here to these Aiyima/Fosi class D’s?

 

[Guddu]

I’m trying to decide whether it would be worth getting a ZA3 for mono functionality or if a Fosi V3 driving just a single speaker would suffice?

Background: I was going to get one A07 Max for the Center speaker, because of its bridged function. However, after Amirs review, I put that plan on pause. I noticed it doesn’t actually provide significantly more power in bridged mono than when driving 2 channels, only a modest 10-20% bump. And those stereo power output measurements are also not in and of themselves much higher than what the Fosi V3 can already provide in stereo anyways.

Question: do you think the Fosi v3 would experience the same type of small 10-20% bump in power output if I only drove my single center speaker from them? Even though it lacks any bridged “switch”? Because I think that would be sufficient power, and then it wouldn’t make sense to wait for the ZA3 and pay more for it too

I know in AVR measurements, which are usually class A/B, the power output drops as you add more and more channels. I’m wondering if that same principle applies here to these Aiyima/Fosi class D’s?

Post in thread 'Fosi Audio V3 Amplifier Review'
https://audiosciencereview.com/foru...-audio-v3-amplifier-review.45757/post-1798566

 

[Jeromeof]

Hello, I am considering buying two Fosi Za3s for the end of the year to do dual mono mode. I already have an Aiyima A07 that I modified a little (replacing the AOPs with two SPARKOS LABS SS3602 + changing the 4 inductors + red WIMA capacitors - the sound has improved a lot compared to the original version). Regarding the new model from Fosi, the ZA3, I was wondering if I could use the MEAN WELL LRS-350-36 Switching Power Supply Module SMPS 36V 9.7A 350W power supplies, I can't find anything regarding this voltage and amperage: 36V -- 9.7A. Do you think my Mean Well power supplies could damage the ZA3s because they would be too powerful for two amps in mono mode?? In advance, thank you, see you later.

I own two A07 MAX amplifiers. As far as I know: the A07MAX is already a bridge output, and the mono amplifier is a parallel bridge. Parallel bridge connection will increase overcurrent, the large dynamic effect will be better, and it can support lower load impedance than bridge mode.

I am not sure with the ZA3 but I believe it is a similar configuration.

 

[Mai.live.in.Tokyo]

I am trying to figure out how you could use two ZA3 in mono bi-amp configuration. The P3 as a pre-amp does not have two sets of RCA out so will there be an upgraded Pre-amp, or is there another alternative I am not considering?

 

[Jeromeof]

I am trying to figure out how you could use two ZA3 in mono bi-amp configuration. The P3 as a pre-amp does not have two sets of RCA out so will there be an upgraded Pre-amp, or is there another alternative I am not considering?

When using the za3 in mono bi-amp you feed the left rca to one za3 and the right rca to the other za3 - so you don’t need 2 sets of rca outputs so the p3 should be fine but I personally would go for a higher quality preamp than the p3

 

[Mai.live.in.Tokyo]

When using the za3 in mono bi-amp you feed the left rca to one za3 and the right rca to the other za3 - so you don’t need 2 sets of rca outputs so the p3 should be fine but I personally would go for a higher quality preamp than the p3

That makes sense, thanks. I would be happier with two sets of RCA out so I could take the two rights to the right amp etc. Is there a recommended pre-amp in this mini component universe for that? Also with twin ZA3s going what is the difference in per channel power vs the V3? I currenlty use the 48V on the Z3 and the power and sound quality all the way up is pretty impressive. That said I am powering a pair of B&W towers so to paraphrase Spike Lee, mo' power, mo' betta.

 

[Skelethor]

Hello, I am considering buying two Fosi Za3s for the end of the year to do dual mono mode. I already have an Aiyima A07 that I modified a little (replacing the AOPs with two SPARKOS LABS SS3602 + changing the 4 inductors + red WIMA capacitors - the sound has improved a lot compared to the original version). Regarding the new model from Fosi, the ZA3, I was wondering if I could use the MEAN WELL LRS-350-36 Switching Power Supply Module SMPS 36V 9.7A 350W power supplies, I can't find anything regarding this voltage and amperage: 36V -- 9.7A. Do you think my Mean Well power supplies could damage the ZA3s because they would be too powerful for two amps in mono mode?? In advance, thank you, see you later.

Of course you can.
the back of the ZA3 mentions that it can work from 24 to 48 v, in which case for your power supply is all you need to know.
Your power supply only has 36v so it's not that strong.
Don't worry about the strength of the voltage, if the ZA3 only consumes 5A, that's all you'll get from your power supply.
What wouldn't be sustainable is if, for example, the ZA3 consumed a minimum of 5A, and your power supply, for example, only consumed a maximum of 3A,

 

[Joe0429]

That makes sense, thanks. I would be happier with two sets of RCA out so I could take the two rights to the right amp etc. Is there a recommended pre-amp in this mini component universe for that? Also with twin ZA3s going what is the difference in per channel power vs the V3? I currenlty use the 48V on the Z3 and the power and sound quality all the way up is pretty impressive. That said I am powering a pair of B&W towers so to paraphrase Spike Lee, mo' power, mo' betta.

If you are using it as a dual mono block, you do not need two RCA sets. If you want to bi-amp the tweeters and woofers separately, the MiniDSP Flex offers digital active crossover functionality. Alternatively, the Schiit Saga can also fulfill the need for two RCA output sets.

 

[Mai.live.in.Tokyo]

Great answer thank you.

My real question remaining is do I get more power per channel with 2 x ZA3 vs a single V3? It appears no, so wondering where I am making a mistake.

 

[K.Kevin]

Great answer thank you.

My real question remaining is do I get more power per channel with 2 x ZA3 vs a single V3? It appears no, so wondering where I am making a mistake.

Why do you say it appears not? What did you read or hear that you are basing that off of?

Every indication suggests that 2 za3’s in mono single channel output will provide more power to each channel than compared to 1 single V3 powering two channels at the same time.

I think whats not really clear is whether you get more power with 2 x ZA3 vs 2 x V3(if only one channel was connected and being powered by them). I asked something similar a few days ago. That is because there’s no measurements of the V3 for one-channel driven specs/power output. In reality, I think it’s theoretically possible that the 1channel output of the V3 could be similar to the 1 channel mono output of a ZA3. In which case, it’s a lot cheaper to use 2 x V3’s as “monoblocks” even if you’re only using one rca and one speaker terminal and half the amp is doing nothing. I wouldn’t really see the downside of doing one channel operation with a V3, in the event that their power output is close enough to the ZA3 but their price difference is high.

 

[Mai.live.in.Tokyo]

Why do you say it appears not? What did you read or hear that you are basing that off of?

Every indication suggests that 2 za3’s in mono single channel output will provide more power to each channel than compared to 1 single V3 powering two channels at the same time.

I think whats not really clear is whether you get more power with 2 x ZA3 vs 2 x V3(if only one channel was connected and being powered by them). I asked something similar a few days ago. That is because there’s no measurements of the V3 for one-channel driven specs/power output. In reality, I think it’s theoretically possible that the 1channel output of the V3 could be similar to the 1 channel mono output of a ZA3. In which case, it’s a lot cheaper to use 2 x V3’s as “monoblocks” even if you’re only using one rca and one speaker terminal and half the amp is doing nothing. I wouldn’t really see the downside of doing one channel operation with a V3, in the event that their power output is close enough to the ZA3 but their price difference is high.

When I made that statement I was looking at the fact that the amp chip is the same and that the power sources were the same. I said "appears" because I thought it likely i was overlooking something. Since I posted that I wrote to Fosi and they have written back confirming the V3 and the ZA3 (in mono) have the same RMS at 4 ohms using a 48V5A adapter. The difference they cite is that the ZA3 supports has XLR connections and the minimum load in mono mode is 2 Ohms. So if I had it connected to my B&W 804 speakers which do dip to 2 ohms now and then, I would look at the ZA3. As it is I have the V3 connected to my B&W 603s which spend a great deal of time at 4 ohms and do not or only very rarely dip to 2. So ultimately for the configuration of my system the V3 is the best mix of output and price. I think the ZA3 in a bi-amp config would be ideal for several other systems though. We are literally spoiled for choices of great [roducts with Fosi from wjat I can tell

Npw your question of could we use 2 x V3 using ony one channel on each is very interesting and I would love to know the answer. As you say, if the mono effect can be replicated using 2 x V3 that is a huge bargain.

 

[Baltima]

Hello Guys,

the ZA3 2Ohm stable in Mono. Mono are PBTL ?
Whats the Price in €uro ?

Thanks

 

[Power Pop 23]

Hello Guys,

the ZA3 2Ohm stable in Mono. Mono are PBTL ?
Whats the Price in €uro ?

Thanks

125 euros at this site

FOSI AUDIO ZA3 Stereo / Mono Amplifier

This small Fosi Audio ZA3 integrated amplifier has the particularity of being able to operate in both stereo and mono mode. It incorporates two TI TPA3255 amplifier chips enabling it to deliver up to 2x150W or 1x240W @ 4Ω.

www.audiophonics.fr

 

[abbazaba]

Looking forward to this one. I really enjoy the V3, but the LA90 is a noticeable upgrade... I'm hoping Fosi gets a little closer with the ZA3, which has the features I like about the LA90 (12v trigger, balanced inputs), but more power.

Currently: USB > D70Pro Sabre > LA90 > SVS Ultra Bookshelf

 

[Fosi Audio]

As I understand it the ZA3 doesn't have a high pass for the main speaker channels so you will be running them full range - not ideal but not the end of the world if your plate amp has adjustable low pass so you can match them. RCA output carries the risk of ground loops, but that's normal for consumer hifi.

Hi friend, there is LFP for the sub-out. The cutoff frequency is 300Hz.

 

[GNK]

@Fosi Audio
These days, it is often more comfortable managing power through smart plugs than cascading 12V triggers.
I also wanted to control the ZA3 through a smart plug, but I read a thread that said if you cut power to an amp that is on and then reapply power, the amp will be in a powered down state.
In order to power up the amp in that state again, I'd have to hold the knob down for a few seconds, and if I did, it would very likely change the volume that was matched to the other when using it as a dual mono.

Is this a difficult thing to fix? An easy to change mono/stereo switch is fine with me, but this could be a deal breaker for me.