Fosi Audio V3 Mono Amplifier Review

[staticV3]

I'm rather stuck as to know what the solution is. May look at getting a test meter but seems daft just to test the output of my Wiim.

A multimeter costs like $10-15 at your nearest home improvement store and is an invaluable tool for any audio enthusiast.

It's all that you need to troubleshoot and fix volume issues like the one you had, and would've likely saved you the cost of an Amp Ultra.

 

[beaker152]

Mine came with two 48 V 5 A bricks, no issue at all.

i received my new 5A bricks and amps today--all quiet and good!

 

[keiron99]

A multimeter costs like $10-15 at your nearest home improvement store and is an invaluable tool for any audio enthusiast.

It's all that you need to troubleshoot and fix volume issues like the one you had, and would've likely saved you the cost of an Amp Ultra.

I have ordered one for a fiver from Amazon so will do the test.

In the meantime, my Wiim Amp Ultra has arrived. And guess what? Even at 100% it's far from ear splitting. I am at a total loss. Remember it was the case with my previous Falcon speakers, not just my newer Neat Petite speakers.

The only other things I can think of are my speaker cables (homemade from mains cable) and the house electrics!

 

[staticV3]

I have ordered one for a fiver from Amazon so will do the test.

In the meantime, my Wiim Amp Ultra has arrived. And guess what? Even at 100% it's far from ear splitting. I am at a total loss. Remember it was the case with my previous Falcon speakers, not just my newer Neat Petite speakers.

The only other things I can think of are my speaker cables (homemade from mains cable) and the house electrics!

Here's what you do:

Download and unzip the 60Hz test tone attached below.

Load it into WiiM Home App, or into any music player that can stream to the WiiM.

Plug out your speakers, but leave the speaker wire connected to the WiiM.

In WiiM Home, temporarily disable any EQ, make sure that Output voltage is set to Full and no volume limits are engaged.

Set all volume controls to 100%, then play the 60Hz tone on repeat. You should not hear anything, as the speakers are plugged out.

Set the Multimeter to Volt AC, then put the two probes between L+ and L- on the speaker end of the speaker cable (but with the speaker disconnected). Alternatively betwen R+ and R- to check both sides.

Which probe goes to which cable does not matter.

Your multimeter should now read ~27.9V

If it's significantly less, then try measuring directly at the WiiM speaker output, so w/o the speaker wire in between.

If that fixes things, then you have the culprit.

If voltage is still low, then you likely have a digital volume reduction applied somewhere in your system without your knowledge.

 

[gwing]

Here's what you do:

Download and unzip the 60Hz test tone attached below.

Load it into WiiM Home App, or into any music player that can stream to the WiiM.

Plug out your speakers, but leave the speaker wire connected to the WiiM.

In WiiM Home, temporarily disable any EQ, make sure that Output voltage is set to Full and no volume limits are engaged.

Set all volume controls to 100%, then play the 60Hz tone on repeat. You should not hear anything, as the speakers are plugged out.

Set the Multimeter to Volt AC, then put the two probes between L+ and L- on the speaker end of the speaker cable (but with the speaker disconnected). Alternatively betwen R+ and R- to check both sides.

Which probe goes to which cable does not matter.

Your multimeter should now read ~27.9V

If it's significantly less, then try measuring directly at the WiiM speaker output, so w/o the speaker wire in between.

If that fixes things, then you have the culprit.

If voltage is still low, then you likely have a digital volume reduction applied somewhere in your system without your knowledge.

To add to this it is worth checking that your source is not limiting the volume. Unless I'm mixing up other posts here I think you said that you were streaming from locally stored files so how exactly is that being done and what connection is being used to send to the Wiim?

Perhaps unlikely but it could also be that those locally stored files have been (badly) recorded at low volume - the easiest way to eliminate these possibilities though would be to test stream directly from Spotify or similar streaming service to the Wiim and see if you can get that to play loud enough.

 

[Rick63]

I just ordered a pair of these with the 48V/10A PS to power my new Monitor Audio Silver 50 7g's that'll be here tomorrow.

 

[mischa]

wiim ultra - Fosi V3 mono - Warfdale Linton.
Radio Paradise Volume at 50% and it is loud enough for me.
The Linton sensitivity ca. 86 dB.

 

[staticV3]

@keiron99
Btw, if you still have the WiiM Ultra + Fosi V3 Mono setup, then here's how many volts you should see there with all volumes maxed out:

WiiM Ultra RCA output: 2V
V3 Mono Speaker output: 18V with RCA gain set to 19dB, and 30+V with it set to 25 or 31dB (heavily clipping then, be careful)

 

[vrobec]

Today I got the mono's. Paired them with the P4 preamp, SMSL PS200 Pro DAC and vintage JBL L110A. So nice sounding setup. Only thing bothers me is the not equaly shining LED's on amps. One is pale orange, the other one is more shiny.

 

[SoySalsaPicante]

Today I got the mono's. Paired them with the P4 preamp, SMSL PS200 Pro DAC and vintage JBL L110A. So nice sounding setup. Only thing bothers me is the not equaly shining LED's on amps. One is pale orange, the other one is more shiny.

The LEDs are angle-mounted on the PCB. If you open the amps up, you can adjust them to get them positioned the same way.

 

[vrobec]

Ok I will definitely do that. Thanks!

 

[Sokel]

Here's what you do:

Download and unzip the 60Hz test tone attached below.

Load it into WiiM Home App, or into any music player that can stream to the WiiM.

Plug out your speakers, but leave the speaker wire connected to the WiiM.

In WiiM Home, temporarily disable any EQ, make sure that Output voltage is set to Full and no volume limits are engaged.

Set all volume controls to 100%, then play the 60Hz tone on repeat. You should not hear anything, as the speakers are plugged out.

Set the Multimeter to Volt AC, then put the two probes between L+ and L- on the speaker end of the speaker cable (but with the speaker disconnected). Alternatively betwen R+ and R- to check both sides.

Which probe goes to which cable does not matter.

Your multimeter should now read ~27.9V

If it's significantly less, then try measuring directly at the WiiM speaker output, so w/o the speaker wire in between.

If that fixes things, then you have the culprit.

If voltage is still low, then you likely have a digital volume reduction applied somewhere in your system without your knowledge.

Maybe one thing to consider only , if I remember well (I may be very wrong though) and that is that TPA32xx does not like open load very much.
If you have already tested some this way just scrap this, my memory about such things is not the best.

 

[staticV3]

Maybe one thing to consider only , if I remember well (I may be very wrong though) and that is that TPA32xx does not like open load very much.
If you have already tested some this way just scrap this, my memory about such things is not the best.

I have not, good call-out!

 

[Rick63]

My pair arrived awhile ago, a day early. Playtime!

They'll be powering my new Monitor Audio Silver 50 7Gs, fed by my Topping D70 Pro Sabre, and a little help from a Schiit Lokius. Also a RSL Speedwoofer 10S MKII to help with the low end.

 

[mike70]

Maybe someone talked before about this... checking the Fosi images about the internals of the product, you can see the nichicon capacitors brand sign as "different" from the official typography.

And... there's some "internet rumors" about they're probably fake. I know surely there's no audible difference, but it hurts anyway.

Any clue?

 

[Rick63]

I love these little amps! I'm really happy that the auto on/off feature works well. I've left my Dynaudio monitors powered on 24/7 for 2 years because auto on feature didn't work properly on them.

I'm sure it's been talked about in this thread, but I'm surprised that they didn't put some rows of cooling holes on the top like the ones on the side.

 

[Freezak]

Regarding ELAC DBR62 post:

These have to be the best hifi speakers for the price, if you like a neutral, non aggressive sound. But they are gourmand with power! They are a bit hard to drive.

Minimum impedance is 4.8 ohms at 110Hz, but phase angle is 50 degrees there as Amir pointed out and effective impedance makes it around 2-3 ohms as Erin reports.



Plan to spend on a good and powerful amplifier. Otherwise they sound thin in the midrange and bass. I have tested them with 5 different amplifiers. They shine with a hybrid amplifier, with subwoofer-like bass at ear piercing levels with no hint of distortion. Beautiful tonality with a Musical Fidelity A1, though lack body. Metallic with a Hypex NC122MP. At present while I look for a suitable amplifier I drive them with an affordable but remarkable for the price Onkyo A-9010 that does the job.



DBR62 midrange is phenomenal. Top end can be a bit rolled off, but it also depends on the amplifier. The A1 drove to extended highs. I compared them with Andrew Jones' Mofi SourcePoint 8s, which are 3k€, and held up amazingly, their sound profile is very similar.



P.S.: I watched a demo with A.J. on YouTube with these speakers and he associated them a 80W Elac class D amplifier. This tells half the story.



P.S.2: We observed a bit hump or peak in high-mids, around 6-8KHz, as Amir's frequency response suggests, that can make them just a little bit shouty in my opinion, but I've seen this depend on the amplifier, although I think it is part of the character of this speaker.

Afaik there's no difference between powering these amps using 2x 48v 5a vs 2x 48v 10a power supplies even for 2 ohm dips? Using these via XLR with SMSL D6s DAC and ELAC DBR62 speakers and i'm quite happy with the volume.

 

[stigger]

I'm really happy that the auto on/off feature works well.

It doesn't: standby mode consumes way too much power. More details somewhere in this thread.

 

[Freezak]

It doesn't: standby mode consumes way too much power. More details somewhere in this thread.

This is true, they consume around 10w per unit in standby mode, which is a lot - i still have to turn them off and even with remote controlled power outlet i have to turn them off using the switch, as obviously there's a pop noise if done using a power outlet remote. I wish there was another way.

 

[Rick63]

This is true, they consume around 10w per unit in standby mode, which is a lot - i still have to turn them off and even with remote controlled power outlet i have to turn them off using the switch, as obviously there's a pop noise if done using a power outlet remote. I wish there was another way.

It doesn't: standby mode consumes way too much power. More details somewhere in this thread.

Thanks for confirming. That is disappointing to hear. I went to do laundry and was gone about 75 minutes and when I got home the amps were cool to the touch so I assumed they wouldn't consume much power in standby. Or it is the power brick that is consuming all the power?