Fosi Audio ZP3 Preamplifier Review

[Boredcarrot]

Guys, I have two subwoofers, but this one only has one low-frequency output. Can I split this one output into two to connect to both subwoofers? Has anyone tried this before? Will it work? Will the low-pass filter still function properly?

Yes you can, I have done that before, it works fine. I'm doing it with my current setup too, but now it's a dedicated sub preamp (for 2x passive subs), not my ZP3.

 

[jayapple]

Yes you can, I have done that before, it works fine. I'm doing it with my current setup too, but now it's a dedicated sub preamp (for 2x passive subs), not my ZP3.

I'm two active subwoofers. I don't want to introduce DSP. That kind of debugging is very troublesome and the effect is hard to tell.
I like this one-size-fits-all approach, directly giving the low-frequency signal without any settings. Thank you for your reply. I bought one and am going to give it a try.

 

[Schlippwhip68]

So in a nutshell, this preamp is ok if you avoid RCA and tone controls…oh and remember to spin the volume down before engagement….nearly forgot that bit.

ZP3 mk2 would be my next rather sharpish move if in Fosi’s position. Drop the side panel anti-op amp fence, add a start/stop to the volume, improve the RCA signal….smooth out the volume gain.

Quite a revision but I probably wouldn’t hesitate is buying one if it was brought into production and stick it in between my iFi Zen One Studio dac and JBL 305 mk2 speakers….I would do that in a heart beat to be honest.

 

[Hapo]

...#metooooo...

...I have a pragmatic attitude @ measurable distortion and noise, but the gain control issues spoil it...

...lesser gain control issues spoiled a Schitt preamp for me...(that and their poor attitude about it)....it is an important thing to get right....(IMHO)...

...I begin to despair at ever finding an acceptable preamp that does not cost more than the rest of my modest system...

 

[babadono]

well I find myself needing a preamp for an outdoor patio system and stumbled on this. Main source will be a FOSI S3 streaming Qobuz. But the not knowing what the volume setting is is a NoGo for me also. I use mixers with linear faders almost exclusively which give immediate visual feedback of settings. A rotary encoder with no visual feedback for a main volume control? No thanks.

 

[Schlippwhip68]

well I find myself needing a preamp for an outdoor patio system and stumbled on this. Main source will be a FOSI S3 streaming Qobuz. But the not knowing what the volume setting is is a NoGo for me also. I use mixers with linear faders almost exclusively which give immediate visual feedback of settings. A rotary encoder with no visual feedback for a main volume control? No thanks.

I think the volume thing with no visual info is a little over blown to be fair.

The newer models have no dimple on the volume so even less info and are a full 3 on plug on the rear rather than the rather limp clover design that was on the earlier models.

It’s just a matter of making sure before you turn on your system everything is turned down to zero. Any mature person with Hifi experience knows this as a standard given practice. Yes mistakes can be made but if you have to look at your system before pressing play for visual feedback as to where the volume is then why can’t you check it manually as well as visually. It really makes no difference and it’s the safer option regardless to turn the system down first. The eyes are more subject to deception than actual physical action as a result of sensible decision.

My ZP3 is now ordered and will arrive tomorrow…without the dimple!

 

[babadono]

so just turn the encoder 10 times CCW?

 

[Schlippwhip68]

The ZP3 arrived today. Quite a bit lighter in weight than I thought it would be. Build quality is typical of recent Fosi gear, good.
So I set it up, popped in the XLR’s, rigging my iFi Zne One Studio which is being fed, hardwired with the new Fiio Link Cable, my iPad A16.

First impressions in all honesty, a little on the drier side of sound. Not quite as resolute as the P4 from Fosi. That said, utterly usable and good to have as a preamp for my rig.

So here goes my warranty possibly but an hour after arrival I decided to pop the hood in the ZP3 and replace the NE5532 op amps.
Getting those glossy sheet plastic panels is easily enough with a good heat gun and flat spud/small spatula and a bit of patience. I unscrewed all the external screws apart for the 4 tiny star nuts holing the small PCB board next to the power supply. Those screws just would not budge! I let them be and worked around it.
It meant I could not remove the board from inside the unit. Instead after removing the side panels used a long pick to prize out the two op amps, it was tricky but they popped out eventually.
I replaced them both with a pair of custom made opa828 dual op amps and reassembled the unit.

After putting the unit back into the rack and hooking everything back up the moment of truth was upon me. I nervously turned the power on making sure everything was turned down first. Power on was fine, relay switch kicked in, fine. I then began to increase the volume and……yes, better!

A huge increase in ‘air’, vocals, organically speaking, sprang to as close to life as I could understand without a physical invitation to the singer himself. Bass, clean and tight life just poured into the soundstage and the center image became rock solid. This was and is a huge improvement and it was worth the effort.

So even with the lack of info on volume which in truth I use my ears for and have good practice of turning thing down before on and the apparent distortion of the tone controls which I never used on the P4 much either and so the machine remains in bypass I have to say this is very much not a weak link in my chain and has brought a great deal of soul to the sound which is not a bad thing at all.

 

[sergeauckland]

S

 

[SoySalsaPicante]

 

[Schlippwhip68]

S

lol….yeah, no surprise here but paid and proved on my side.
Even those 0.1 Murata caps make a difference that’s clearly heard in a blind test so how do you like those apples!

 

[RandomEar]

lol….yeah, no surprise here but paid and proved on my side.
Even those 0.1 Murata caps make a difference that’s clearly heard in a blind test so how do you like those apples!

Don't you get tired of "proving" things without offering any... proof? Like, do you not see that all you do is confirming your bias again and again by not testing with the absolute minimum of required controls and getting useless results again and again and again?

 

[Schlippwhip68]

Don't you get tired of "proving" things without offering any... proof? Like, do you not see that all you do is confirming your bias again and again by not testing with the absolute minimum of required controls and getting useless results again and again and again?

I don’t think you can grasp bias in the first place. I don’t have any towards electronics. I do not hold any loyalties to any products in any capacity when it comes to sound quality.

NE5532 are not a fully neutral chip in the first place. They have slight colouration in the low frequencies.

They have been around long enough for many people over the decades to prove this countless times.

Your comment is bereft of any real perspective of the history of said product which leave me questioning what exactly you are bias towards.

The opa828 in the essence of neutrality surpasses the NE5523 by a country mile.

This is obvious in the end game.

I am also not part of the crowd whom holds measurements as the plumb line of end sound, merely a guideline for appropriate engineering.

If the computer says no, it’s not the absolute I settle on, ever.

 

[RandomEar]

I don’t think you can grasp bias in the first place. I don’t have any towards electronics. I do not hold any loyalties to any products in any capacity when it comes to sound quality.

That sentence 100% confirms that you do not know or understand what cognitive bias is and how it works. I'll link this once again and maybe one day, you'll take the time to read and understand how it affects you the same as it affects any other human. Cognitive bias is not "I like this" or "I don't like this".

NE5532 are not a fully neutral chip in the first place. They have slight colouration in the low frequencies.

Any evidence for this claim whatsoever? Because as far as I remember, we discussed this to death already in other threads.

They have been around long enough for many people over the decades to prove this countless times.

Again, feel free to link to that proof.

Your comment is bereft of any real perspective of the history of said product which leave me questioning what exactly you are bias towards.

History is not relevant to measured performance. I personally couldn't care less if a chip has been around 5 months or 50 years - if it performs well, I'm happy.

The opa828 in the essence of neutrality surpasses the NE5523 by a country mile.

It may measure better in isolation or have better basic specs - I didn't check, but there are many op amps which perform better than the NE5532 in certain aspects.

This is obvious in the end game.

I am also not part of the crowd whom holds measurements as the plumb line of end sound, merely a guideline for appropriate engineering.

If the computer says no, it’s not the absolute I settle on, ever.

What?

 

[Schlippwhip68]

That sentence 100% confirms that you do not know or understand what cognitive bias is and how it works. I'll link this once again and maybe one day, you'll take the time to read and understand how it affects you the same as it affects any other human. Cognitive bias is not "I like this" or "I don't like this".


Any evidence for this claim whatsoever? Because as far as I remember, we discussed this to death already in other threads.


Again, feel free to link to that proof.


History is not relevant to measured performance. I personally couldn't care less if a chip has been around 5 months or 50 years - if it performs well, I'm happy.


It may measure better in isolation or have better basic specs - I didn't check, but there are many op amps which perform better than the NE5532 in certain aspects.


What?

Ciao!

 

[Schlippwhip68]

Another point is all the hysteria over the volume knob and visual feedback.
It’s all a little overblown imo. I wouldn’t let this issue break the deal either for the ZP3 as the buyer would lose out on a very capable preamp for the sake of of a small learning curve.

The degradation of sound quality when using Tone Control is not huge by any means and other reviewers have mentioned this and gone into detail over the issue and again it’s only a very small reduction in clarity. Bypassing the tone control and simply using EQ within software is by far better than any Tone Control on any hardware regardless of price so again it’s should not be considered a deal breaker and to not recommend this pre amp on these grounds seems a little childish. Tone Control muddies stuff on almost everything and is a known common issue and has been for decades. It’s the cheapest EQ on the planet and to be honest think Fosi should have not included at all.

The Tone Control was dropped by many manufactures of serious Hifi gear quite sometime ago for good reason and with today’s advances in software etc, they are less needed today than ever before.

I have never used Tone Control on any equipment far more expensive than the ZP3 to any real good effect. Seperate EQ is always the better choice.

I literally do not rely on visual feedback for what my ears may allow me to discern as to what is too loud or not as the case maybe.

I never did while I was DJing either, any distortion would be clearly heard rather than visually understood but it was still handy to have the red led go bananas when I was driving the system too hard.

In regard to surprise bursts of volume then just get into the good professional practice of turning everything down either before you turn everything off or on!

I actually prefer the digital control here over the P4’s analogue motorized pot which when using the remote is clunky/jumpy in response. The ZP3 is really smooth.

Just my two pennies.

 

[babadono]

if there's no indication of what level the volume is, how do you turn it down? Like I posted before just turn the volume knob 10 full CCW rotations and hope that is zero or close enough? In my system I lost track just now at 20 counting the number of controls that could adjust volume or gain. No way am I turning those all down to minimum because the main control has no indication where it is set. Just my $0.02. Enjoy the music.