Fosi v3 Mono - User Impressions | Owner's Thread

[jboyer]

After a couple of months of using my v3 Mono's through the XLR inputs, I decided to try them on the RCA's.

Well, through RCA, the volume output of one of the monoblocks is noticeably lower than the other's. Through XLR, they are perfectly well balanced.

Did anybody notice such a situation with their's?

Can it be the source? Will swapping the FOSIs confirm that one is different?

 

[JLB321GO]

Can it be the source? Will swapping the FOSIs confirm that one is different?

The same source connected with RCA -> XLR adapters exhibits no issues.

 

[CReeDeR]

After a couple of months of using my v3 Mono's through the XLR inputs, I decided to try them on the RCA's.

Well, through RCA, the volume output of one of the monoblocks is noticeably lower than the other's. Through XLR, they are perfectly well balanced.

Did anybody notice such a situation with their's?

Look at the back of your monos. There is a gain switch for RCA input. 25db and 31db. Are they at the same position?

 

[JLB321GO]

Look at the back of your monos. There is a gain switch for RCA input. 25db and 31db. Are they at the same position?

You hit the Jackpot!!!
That was it. Thank you!!

 

[CReeDeR]

You hit the Jackpot!!!
That was it. Thank you!!

No problem. I already suspected that. It's often the simplest things.

 

[Negatywny]

I was just about to make this advice but then i'm like... f'this, it can't be it xD

 

[Jimbob54]

Fosi V3 Mono Thoughts
So I Have Had These Amps For A couple Of Month Now And This Has Allowed Me To Fully Assess Them And Hear How They Perform.
I Won't Go Through The Specs, Since This Information Can Easily Be Found
I Have A Fosi V3 Stereo To Compare Them Also A PrimaLuna Evo200 ,BottleHead Streomour, Spendor D40 And Bryston 4B3
I Tried All The Input Variants; RCA Low And High Gain + 5’ XLR Cables With Short Speaker Cables (30cm) I Haven't Swapped The Originals Op-Amps For This Test Since I Don't Have Any So They Were Ran ‘Original’ And Fed Individual 48V/5A PS Per Channel.
First Thing I Noticed Using XLR Inputs Is That You Do Need A Preamp With At Least 10db+ Of Gain If Dynamics And Loudness Is What You Enjoy.
I Have An Audiolab MDAC+ On Hand That I’ve Used As A Preamp And DAC . It’s Maximum Output Voltage Is 4.5 Volts With No Additional Preamp Gain.
More "Gain" , Is Not What I am After In My Set-Up. Most Of The Time, Passive Preamps Will Do Or Source Direct With A Passive Potentiometer.
I Know That Some Users Might Want More “Oomph” Out Of These Units. I Was Listening The V3's At –13Db On Mdac+ To Get A Decent Sound Pressure Out My LS50 Metas
At A 7 Feet Distance. Loudness Was More Than Adequate But Some Extra Gain Will Be Suitable Via The Preamp To Extract Some More “Punch” Out Of The Speakers.
This Was Of Course In Balanced Mode . The Kef’s Did Not Sound Lean Or Lacked In Dynamics In Any Way. I Enjoyed Them Despite The Low 20db Gain The Amps Provide In XLR Now If You Have More Sensitive And Easier To Drive Speakers ,This Will Not Be An Issue And The Speakers Will Shine And Perform As They Should.
Later, I Tried The RCA Inputs With Gain Set At 31db Using My Metrum Acoustics Octave Dac Connected To A Passive Potentiometer (No gain) .
Now, It Was Dynamic And Contrasts Where Easier To Discern And Follow. This Octave Dac Has A Little More ‘’Impact’’ And Bass Presence Compared To My MDAC+ Thereby The More ‘’Beefy’’ And Contrasted Sound Perception Was Back. Sound Is Clear With An Easy Way To Discern The Different Instruments. Image Felt Taller And Wider Compared To The Fosi V3 Stereo But Not By Much. One Of My Favorite Set-up Was Using The V3 With Chord Mojo As a Dac And Pream. This Configuration Is Very Compact And ‘Cheap’ To Acquire. 2x Mono Amps + preamp And DAC Under $1000 ! The Mojo Can Go up To 4V before Clipping So Fosi’s Were Used In Their 25db Gain Mode To reach Better SINAD The Synergy Was Really Good Overall And I Did Crank Up The Volume With Good Results.
The Amps Have The Capacity To Reveal What You Are Feeding Them Upstream. Different Sound Traits Of Different DAC’s Are Well Presented And The Amps Wont Be ‘’Obscuring” Them. The V3’s Won't Be A Limiting Factor To Your Set-Up And That Is A Good Thing Considering The Asking Price.
Now , Comparing Them With My Tube Amplifiers It’s A Matter Of What Signature Sound You Are After. The Primaluna Evo 200 Gives Me More Of The 3D Effect And The ‘’Virtual’’ Space That Usually Transistor Amps Can’t Match. They Still Provides The Depth And Width Soundstage But Not To The Same Extent.
The Highs In General Are A Little Sweeter And Timber Sound More Natural To Me. Especially With The Bottlehead Amp . All This Is Noticeable But Not By Much .
When i Am Listening In "Nearfield", My 4 Watts Amp Will Suffice. ( 5 to 6 feet distance)
For Me, The Amps Would Be An Ideal Set-Up If You Are After A Home Cinema System. Especially If You Want To Amplify 5 Individual Speakers. Small, And Easy To Hide They Will Provide The Watts Needed To Enjoy Your Movies. I Have Found Them To Run A Little ‘’Hot’’ Compared To My Similar Wattage Fosi V3 Stereo. It’s Not An Issue For Me But Some Might Find This Being A Concern. So To Conclude, I Think That The Amps Are Great If You Are Seeking High Wattage, Neutrality And Decent Transparency. They Will Just Get Out Of The Way And Let You Enjoy Your Music And Movies. Now, Swapping The Op-Amps Might Let You Reach A Little More ‘refinement’ But That is To be Determined In A Sound Comparison. Hopefully Fosi Will Come Out With A Nice Preamp With XLR Outputs To Complement The V3 Mono’s.
Thx

I believe you are legit but please don't ever use whatever software you used to assist with this post ever again.

 

[SMen]

I believe you are legit but please don't ever use whatever software you used to assist with this post ever again.

Can you explain this? "don't ever use whatever software you used to assist with this post ever again"?

Was this translation software or such that @Yeti used?

I'm just wondering because it does indeed seem a genuine post when reading it.

Scary moderation stuff.

 

[Jimbob54]

Can you explain this? "don't ever use whatever software you used to assist with this post ever again"?

Was this translation software or such that @Yeti used?

I'm just wondering because it does indeed seem a genuine post when reading it.

Scary moderation stuff.

Not sure what you want me to explain. I don't believe the poster sat and typed that due to the eye watering formatting . Which leads me to think some software was used to assist /translate . If so , it needs to never be used again .

 

[SMen]

Not sure what you want me to explain. I don't believe the poster sat and typed that due to the eye watering formatting . Which leads me to think some software was used to assist /translate . If so , it needs to never be used again .

He could do with spacing the paragraphs better to make it more readable, that is for sure! But the sentiment and intention seems good.

 

[Jimbob54]

He could do with spacing the paragraphs better to make it more readable, that is for sure! But the sentiment and intention seems good.

The paragraph spacing wasn't what made my eyes water.

Nor was I referring to the sentiment or intention. I'll let the membership comment on that .

 

[JLB321GO]

Is that a bot?

 

[Yeti]

hello , i did not use any Software ! Not Sure What You Mean By That. i was actually trying to convert my review from a PNG but could not make it to work so we can read it here. Other Option I have is A link To The Review
i have tried to space the paragraphs better . I can add some pictures next week if needed also
Now If You Think Is Not Appropriate , I can Delete It.

 

[EddNog]

hello , i did not use any Software ! Not Sure What DO You Mean By That. i was actually trying to convert my review from a PNG but could not make it to work so we can read it here. Other Option I have is A link To The Review
i have tried to space the paragraphs better . I can add some pictures next week if needed also
Now If You Think Is Not Appropriate , I can Delete It.

Seems fine. I think the formatting is weird for us. Like Why Is Every Word Individually Capitalized?

-Ed

 

[Jimbob54]

hello , i did not use any Software ! Not Sure What DO You Mean By That. i was actually trying to convert my review from a PNG but could not make it to work so we can read it here. Other Option I have is A link To The Review
i have tried to space the paragraphs better . I can add some pictures next week if needed also
Now If You Think Is Not Appropriate , I can Delete It.

As @EddNog says , the capitalisation of nearly every word is very jarring to try and read .

Apologies , I assumed some software had been used and added all the capital letters as your other posts didn't look like that .

By all means post a link if youve posted it elsewhere.

 

[jboyer]

I hook up a Wiim Ultra to freshly unpacked monoblocks.
When the Ultra goes to sleep, the FOSIs remain On, no matter how long the Ultra is sleeping. I set the power switch to auto.
Any suggestions?

 

[jboyer]

As noted in my earlier post, the Wiim Ultra drives the two monoblocks which replace a NAD 3045. The line out was used for the Nad to bypass its DAC.
After a few hours of operation, and adjusting the Ultra room equalization to the new set up, the overall experience is mixed. My wife describes the sound as dry, with no depth.
Part of the issue seems to be the need to listen to the V3 at a higher volume to be more pleasant.
I played with the EQ, with mixed results.
Is it possible that at some lower levels, the NAD kicked a loudness EQ?
I am not sure what to do next, to satisfy my wife and resume harmony in the house

 

[Guddu]

As noted in my earlier post, the Wiim Ultra drives the two monoblocks which replace a NAD 3045. The line out was used for the Nad to bypass its DAC.
After a few hours of operation, and adjusting the Ultra room equalization to the new set up, the overall experience is mixed. My wife describes the sound as dry, with no depth.
Part of the issue seems to be the need to listen to the V3 at a higher volume to be more pleasant.
I played with the EQ, with mixed results.
Is it possible that at some lower levels, the NAD kicked a loudness EQ?
I am not sure what to do next, to satisfy my wife and resume harmony in the house

WiiM Ultra does not have EQ?

 

[jboyer]

It does. But none of predetermined choices seem to help.

 

[Petrushka]

It does. But none of predetermined choices seem to help.

The built in curves are not intended for correction.