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Fosi ZH3 Balanced Headphone Amp & DAC Review

Rate this DAC & HP Amp

  • 1. Poor (headless panther)

    Votes: 2 0.9%
  • 2. Not terrible (postman panther)

    Votes: 10 4.7%
  • 3. Fine (happy panther)

    Votes: 63 29.4%
  • 4. Great (golfing panther)

    Votes: 139 65.0%

  • Total voters
    214
Does anyone know if I can run this from a USB-A connection? I'm using a hub so I only have one cable into my computer, so I'd like to use e.g. USB-A -> USB-Micro cable and a USB-Micro -> USB-C converter.

One of those things that "should maybe" work, but doesn't always.
Answering my own question: Fosi say it should work fine, just make sure the cable is well enough rated for data transmission.
 
Has anyone tried using SX52B/45B/35B or SparkoS SS3602 in ZH3? I've recently bought a ZH3 and wanted to play with discrete amps. SS3602 are currently too expensive for my purposes of experimenting with sound, on the other hand I've read that SX52B and SX45B are incompatible with ZD3 DAC and I'm afraid they might not work in ZH3 too. I would also like to get a bit more massive and deeper sounding bass without using EQ (staying in bypass mode) if possible, some reviewers say that MUSES02 can give more bass to ZH3, but I'm afraid buying these as there are a lot of counterfeit MUSES02 chips on the market...
 
Has anyone tried using SX52B/45B/35B or SparkoS SS3602 in ZH3? I've recently bought a ZH3 and wanted to play with discrete amps. SS3602 are currently too expensive for my purposes of experimenting with sound, on the other hand I've read that SX52B and SX45B are incompatible with ZD3 DAC and I'm afraid they might not work in ZH3 too. I would also like to get a bit more massive and deeper sounding bass without using EQ (staying in bypass mode) if possible, some reviewers say that MUSES02 can give more bass to ZH3, but I'm afraid buying these as there are a lot of counterfeit MUSES02 chips on the market...
If you really wanna spend your time and money on that type of nonesense, get yourself at least 2x similar/same type of devices where you can swap the op-amps and connect those to an pre-amp/receiver where you can do fast A/B switching while keeping same level matched source signal.

Its the best and fastest way to lose that "magic sound hardware" illusion which is being sold to you by bunch of snake oil brands/reviewers on every corner.

Back in time, there was a reason why those type of snake oil guys were trevelling merchants and couldnt stay for long in one town... Nowdays they are far away from their customers, so they feel like they can sell the snake oil again and even more then ever by spreading a mass of manipulative and false informations and sponsoring/hiding their false claims and ads as "reviews" or "test".
 
If you really wanna spend your time and money on that type of nonesense, get yourself at least 2x similar/same type of devices where you can swap the op-amps and connect those to an pre-amp/receiver where you can do fast A/B switching while keeping same level matched source signal.
curious if you’ve done this yourself? I would suggest using low distortion headphones/IEM rather than speakers to remove the effects of the room.
 
curious if you’ve done this yourself? I would suggest using low distortion headphones/IEM rather than speakers to remove the effects of the room.
I have 2x ASUS ST/STX II soundcards (HPA/DACs if you wish) where you can swap the buffer and I/V convertor op-amps, connected simultaniously to my PC (maxed out identical signal source), going over RCA into an older Denon stereo receiver (acts as both amp or a pre-amp> separate Fosi ZA3 amp if needed). The output stage are 3-way speakers. And i also have a bunch of op-amps laying aroung (even Burson V7Cs) for testing.
So all it takes is just pressing 1 button to switch between the two soundcards which have swapped op-amps to have a direct level matched comparsation, without even changing my sitting position.

I have not done any testing with HP since it would require an physical repluging between the devices.

I have also done the "classic" swapping before, where you dissasamble the unit, swap the op-amps, change your listening position, touch the volume knob, let couple of minutes pass and then try to focuse on that "moist and deep bass" you read/heard about on some forum or YT review.

What sets a dumb person from a smart appart is the fact, that a smart person knows that he is dumb and is willing to learn. While a dumb person thinks that he already knows everything.
 
… a smart person knows that he is dumb and is willing to learn. While a dumb person thinks that he already knows everything.
also the possibility that a dumb person who is willing to learn will continue to make dumb decisions…

I just pulled the trigger on a second ZH3 to side by side (like you suggested) with the first unit I have with V7V op amps. Both will feed into another transparent headphone amp with multiple inputs to swap back and forth. I have done the classic swap and compare 5 minutes apart but I agree it’s nothing like the comparisons I’ve done with speakers and RME totalmix “snapshots” to swap parts of the chain instantly and seamlessly. I’d still prefer to use headphones to compare small scale signal chain adjustments as it’s much easier for me to hear effects like reverb without the room I’m in adding its own decay.

I do not have access to a nice measurement rig, but the from my unblind, biased tests the perceived difference I’ve heard between Burson V7V and V7C is not the freq response or distortion, it seems related to the impulse response or transient decay. In theory this difference should be measureable - just like the differing impulse response of bass reflex vs horn loaded subwoofers (although much less significant with op amps). Both subwoofer types can be tuned flat and measure similarly low distortion, but there is still an audible difference in the way that they resonate a room imo.

All that to say I’m still open to the possibility that op amps have an impact on the sound, even if it’s a 1-2% difference. There are audio engineers who have spent thousands of dollars on reverb hardware and it’s got a similar vibe to me - ie. the differences probably are not obvious on every consumer sound system, but does that mean hardware reverb is snake oil?
 
I do not have access to a nice measurement rig, but the from my unblind, biased tests the perceived difference I’ve heard between Burson V7V and V7C is not the freq response or distortion, it seems related to the impulse response or transient decay. In theory this difference should be measureable - just like the differing impulse response of bass reflex vs horn loaded subwoofers (although much less significant with op amps). Both subwoofer types can be tuned flat and measure similarly low distortion, but there is still an audible difference in the way that they resonate a room imo.

All that to say I’m still open to the possibility that op amps have an impact on the sound, even if it’s a 1-2% difference. There are audio engineers who have spent thousands of dollars on reverb hardware and it’s got a similar vibe to me - ie. the differences probably are not obvious on every consumer sound system, but does that mean hardware reverb is snake oil?
The funny part is: While i did the "classic" swapping i had like 8 different op-amps combos and was going back and forth and indeed i was thinking i could hear all the tonal changes like wider soundstage, tighter bass, brighter mids, more details and so on. In reallity it all comes down to the listening position and gain. Simple rule: more gain = better subjective sound.

I was actually trying to make some sort of a table and write down all my subjective experiences for every single op-amp combo up untill i couldnt hold all those combos from each other anymore. At some point i noticed, that they all kinda started to sound the same to me, i almost went nuts while rolling. So even before i was able to do the level matched A/B testing, it already got me into thinking... Something wasnt right.

Another fun fact: for whatever reason i didnt liked how the Bursons sounded (being the most expensive) and actually prefered the Aliexpress ones (Oraclle II).

The sound wave and hardware behind it is not a magical and mythical thing. Even if 90% of Audio-Industry folks are trying to make you believe so.

The magic comes from your brain and it seems like ppl around 35+ are starting to lose their hearing capabilities and start to seek for that once belowed sound they still think to remember. Thats where the "Audiophile hobby" kicks in and all of those snake oil guys are already waiting for you.
And no, not everything is snake oil. Especially not from an objective engineering perspective. Well measuring and built, feature packed long lasting quality devices are always welcome
 
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… it all comes down to the listening position and gain. Simple rule: more gain = better subjective sound.
I agree with you 100%. With speakers the listening position and changes from room acoustics are what matter the most. I mostly use headphones at home, so two ZH3 fed the same digital signal at the same gain level will remove those subjective variables.

At some point i noticed, that they all kinda started to sound the same to me…

Another fun fact: for whatever reason i didnt liked how the Bursons sounded (being the most expensive) and actually prefered the Aliexpress ones (Oraclle II).
So you simultaneously couldn’t hear a difference but also could tell which one you preferred? ;)

The magic comes from your brain…
Again I agree completely. What we hear is only a snippet of perspective in a moment of time. Even with two of the same exact chain feeding headphones and an instantaneous switch, what continues to change is my state of consciousness and that’s much harder to isolate ;)

I think it’s funny that a lot of people talk about getting into tubes when they get older, but I feel like I’m the opposite where I want MORE transparent gear the older I get… tubes color the sound in a way that I find distracting, but the theory that op amps could have a slight impact on sound without degrading the signal is what appealed to me. The “hifi” gear I’ve accumulated now sounds better than anything I heard in my youth and a lot of it has measurements here and elsewhere to confirm it’s stellar performance (Zero 2 IEM, HE6SE headphones, DX5II, ZH3). I wouldn’t consider any of my gear to be relatively expensive compared to what I see others pay for incremental gains. Op amps are the most “oily” audio products I’ve bought for sure after trying high end tubes, all my cables and power supplies are cheap but well built. At this point I’ve spent almost $500 on op amps and an extra ZH3 but I might very well end up where you have and determine, like I have for tube rolling, that it’s a waste of time and money. I’m pretty open to either outcome, but I have to do more research before I can say any more
 
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I’m currently waiting for a second ZH3 to side by side op amps (into 3rd HP amp with a switch). Decided to run a side by side last night with ZH3 (V7V op amps) and DX5II both in pure DAC mode (source: WIIM mini digital out), and I had to turn down the DX5II (5Vrms) -2db in order to level match the ZH3 (4Vrms).

The difference was subtle, but it was there. There were several times where the HF stood out to me and I looked over realizing I was listening to the DX5II chain. I found myself switching to the ZH3 and forgetting it for longer periods. Not a very scientific method but personal preference isn’t always replicable and I wouldn’t say one DAC is better than the other. They both have useful features and it would have been nice to have one unit that combines the best of both worlds (RCA in, adjustable tone controls, EQ presets, all outputs active, swappable op amps, etc.)
 
A very fine device. Analog RCA input is very much appreciated. I use it with a variety of headphones or a ZA3 power amp powering the speakers.

Two slight drawbacks: one should never use the LO mode with a power amp without a volume dial (or with the volume turned up), maybe you would blast your speakers, ears or both. Disabling the LO function in the menu would be a nice feature.

It's a bit nitpicking, but the black finish of the ZH3 is a bit darker than the ZA3. The differences may be exaggerated by the way the light falls on the stacked devices.
IMG_7647.jpeg
 
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… one should never use the LO mode with a power amp without a volume dial (or with the volume turned up), maybe you would blast your speakers, ears or both. Disabling the LO function in the menu would be a nice feature.

View attachment 490471
Nice stack! Just a tip - if you double click the volume knob it will switch between Headphone Out and Aux Out, so you never have to worry about accidentally hitting LO (like you do in the menu)
 
Nice stack! Just a tip - if you double click the volume knob it will switch between Headphone Out and Aux Out, so you never have to worry about accidentally hitting LO (like you do in the menu)
Yes, we have specifically excluded the LO mode in the shortcut keys to prevent accidental damage to the device or ears due to excessive volume;
 
I see this mainly as the replacement for the "aged" Topping DX3Pro+
For similar price we now get balanced as well and in my eyes a nicer design
I have both on my shortlist, the Fosi is generally cheaper here in the UK. I know the Topping is proven (my son has one and loves it) any reason to choose one over the other from a functional / reliability PoV? I'm going to be running a Wiim Pro with EQ enable into mostly sensitive devices below 100 ohms.
 
I see this mainly as the replacement for the "aged" Topping DX3Pro+
For similar price we now get balanced as well and in my eyes a nicer design
Somewhat true, the SMSL DL100 is a contender too, has a bluetooth and HDMI ARC, but no analogue input, looks a lot more pedestrian, has more single ended power but no true balanced headphone out. So it depends on your needs what device suits you best.
 
Ali Express price is £128 delivered to the UK. Bonkers, but no warranty if it goes up in smoke....

It was sat in my basked for a couple of hours, decided to pull the trigger anyway, but had an error message, some discounts had expired so had to refresh. The new price was £120, so maybe I should have waited another couple of days :D

Edit 2: a further £8 in cashback so net all in delivered is £112. I feel that is one heck of a bargain, as it's showing £179 in Amazon UK atm. I bought from the Fosi store on AE so it should be genuine
 
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Ali Express price is £128 delivered to the UK. Bonkers, but no warranty if it goes up in smoke....

It was sat in my basked for a couple of hours, decided to pull the trigger anyway, but had an error message, some discounts had expired so had to refresh. The new price was £120, so maybe I should have waited another couple of days :D

Edit 2: a further £8 in cashback so net all in delivered is £112. I feel that is one heck of a bargain, as it's showing £179 in Amazon UK atm. I bought from the Fosi store on AE so it should be genuine
Pretty incredible. That’s basically 2 ZH3 for the same price as DX5II…
 
My Wiim pro cost me £130 so £240 ish and I've got a decent streaming setup. My only disappointment is that the Fosi is "only" 640mW into a low impedance load compared to 1200mW for the JDS. I don't have my LCD-X any more otherwise that might have been an issue.
 
My Wiim pro cost me £130 so £240 ish and I've got a decent streaming setup. My only disappointment is that the Fosi is "only" 640mW into a low impedance load compared to 1200mW for the JDS. I don't have my LCD-X any more otherwise that might have been an issue.
LCD-X (and basically any power hungry headphone these days) can be run balanced, so in reality the ZH3 offers 2x as much power as the JDS you mention.

I’ve got an old AKG K340 that’s wired SE and thus it’s harder to drive to loud levels than even my HE6SE, but the ZH3 has no problem driving it to louder than comfortable levels (including a massive bass boost).
 
Fair point, though the phones I currently have are not able to be run balanced.
 
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