Fosi Audio P4 Preamplifier Review

[EeeGee]

Excellent for what it is but the lack of triggers out and subwoofer out are too limiting .

Thanks for the review Amir.

 

[DavidM1]

It feels like objective hifi has hit critical mass. Here is the demand and here are the suppliers with the nous to meet it. Bravo to these fabulous Chinese companies.

 

[Rja4000]

A good cheap preamp with remote and defeatable bass/trebble ?
Awesome !
I want one !

Thanks for reviewing this !

 

[Mort]

Not needed but I want one 'just in case' One never knows when an extra RCA switch might be helpful, right?

 

[MCH]

Excellent! motorized knob is the only valid alternative to no display, and better in my opinion.
I do miss though something more than the trigger: that the gain could be adjusted independently for each input. I know it is too much to ask for, but this is something i always missed in my cheapo integrated.

 

[welwynnick]

Thanks Amir. What a nice little preamp.

It's the answer to the common question "should I use a passive volume control in my system?".

I love the distortion vs level vs frequency chart. That's how it should look!

 

[Miley_B]

I don't need this but it looks an excellent, tidy unit and it's really good to see tone controls... possibly....
Any info or traces showing the tone controls in use? Frequency, cut/boost range, Q?

 

[regan]

As preamplifiers go, I prefer the features offered by select WiiM streamers

Can you expand on that?
Also I didn't know they can be used as preamps, pretty cool

 

[Power Pop 23]

Can you expand on that?
Also I didn't know they can be used as preamps, pretty cool

A WiiM streamer can apply Parametric EQ to sources connected to it, including via Wi-Fi and Bluetooth.

 

[Old_School_Brad]

I like this.

 

[Sokel]

Yep, that does it.
No more excuses for those crying after yet another accident with a DAC>amp.
Peace of mind with minor (certainly inaudible) penalty (and at occasion, with a little effort and measurements far better gain structure and noise with one of those)


Thanks Amir!

 

[morillon]

This is a good preamp, nicely done. I especially like the inclusion of treble/bass controls and a motorised volume pot.

Thanks @amirm for the thorough testing.

Pic;

View attachment 436216


JSmith

good old..."very old"... 5532 ...in dip (help to sell, right? ;-) )
;-)
(the very very...very large part of what we listen to has been played a large number of times , over the course of production, in this AOP... one of the "best knowledge of our music""..hihi)

 

[Old_School_Brad]

It's a shame it's not a Bluetooth remote, so it could be tucked away in a cupboard, out of view.

 

[NorthernSoul73]

A WiiM streamer can apply Parametric EQ to sources connected to it, including via Wi-Fi and Bluetooth.

Agreed. I’ve tried comparing my turntable’s phono preamp connected to the WiiM’s line-in versus going straight into my Naim amp, and I’m struggling to hear a difference. Granted, it takes me about seven seconds to switch, by which time any nuances are lost on me, but aside from a difference in gain, I’m hard-pressed to notice any variation. Plus, with the ability to EQ a 65Hz room node, the WiiM is a win for me.

 

[JakeK]

The start of the review says 'budget preamp' but unless you need more features or inputs there is no need for a better one. If ever need to add volume control or more RCA inputs to a system then this is what I will buy. I voted great and I would vote higher as I don't think I've seen a preamp this good at this price level.

I actually want preamp with a DAC, LDAC and DSP and more but then that's a different matter, another price level and maybe a almost different class of device and off topic.

Great product!

 

[morillon]

output impedance?

 

[Tofffsy]

I see an opamp inside this preamp, in which part of the circuit is it located? Is it linked to the use of the Gain and otherwise bypassed if used as passive or not?

 

[antcollinet]

I see an opamp inside this preamp, in which part of the circuit is it located? Is it linked to the use of the Gain and otherwise bypassed if used as passive or not?

The bypass is for the tone controls. This is an "always active" preamp. The op amp will provide gain and low output impedance.

 

[Gremlins]

What is left to McIntosh, accuphase and all the other esoteric brands that sells for thousands and thousands...

 

[mike70]

No more excuses for those crying after yet another accident with a DAC>amp.

That's why I want a balanced version . Today only exists a Douk Audio passive unit (balanced, fair price), but without remote ... and without Amir review (only the switch was reviewed).