Fosi Audio V3 Mono Amplifier Review

[Kimbrough Xu]

Question: I’m considering to maybe cancel the SP601 speaker part of my pledge, and just keep the mono’s (in other words: requesting money back for the speakers).

Is that something that I can do, or does that violate the whole Kickstarter idea?

Just contact fosi audio, I am sure they will solve this for you.

 

[Owis]

Just pulled the trigger on 2x V3 + 10A psu. USD 224 incl. free shipping to Norway. Even allowing for VAT, this will only be 15% more for 2x than purchasing 1x from the new Norwegian distributor. Fantastic deal.

Where from may I ask?

 

[mags65]

Direct from Fosi using their coupon.

 

[iLoveCats]

Finally received my order today. Backer 97. I ordered two monos and one 10a supply with a Y cable. What I received was two monos and two 10a power supplies. I guess that's ok since it was determined later that 2 supplies is better than 1 and 1 required an additional filter.

 

[johnmartmill]

Just hooked up 3 of these guys to my Denon X6700H receiver via RCA, ran Audyssey and I'm getting an error that says all three are out of phase. I confirmed that all are wired properly. Any ideas why this is happening?

 

[Miser_Audioman]

Just hooked up 3 of these guys to my Denon X6700H receiver via RCA, ran Audyssey and I'm getting an error that says all three are out of phase. I confirmed that all are wired properly. Any ideas why this is happening?

I found the phasing on the v3s to be reversed from standard, see owners thread

 

[Miser_Audioman]

Cure, switch the wires. Thankfully none of my friends or guests give a crap about audio, so they won’t look behind and see that I have my amps hooked up ‘wrong’ lol

 

[Bleib]

I found the phasing on the v3s to be reversed from standard, see owners thread

How in the bleep can this make it out from the factory?

 

[Miser_Audioman]

Dunno- the start of the measurements
Post in thread 'Fosi v3 Mono - User Impressions | Owner's Thread'
https://audiosciencereview.com/foru...-impressions-owners-thread.54043/post-2033602

 

[jvdburgt]

So all of them are like that and need to be hooked up in reverse, or what?

 

[Miser_Audioman]

Both mine are reversed

 

[Petrushka]

Is there an official standard for polarity, other than the obvious requirement for the same color to indicate the same polarity for all channels? Seems that there was a craze for absolute polarity a while back.

 

[jvdburgt]

Noob question: but if all your speakers have polarity reversed, all is fine then, or is it something objectively inferior?

 

[johnmartmill]

Wow, this is crazy. I mean I don't care how things are wired, but it gives me serious reservations about the quality of the product. How many people are going to run their speakers out of phase because they don't have a room correction software to check? This is bad, Fosi. This is really bad.

 

[EddNog]

Noob question: but if all your speakers have polarity reversed, all is fine then, or is it something objectively inferior?

When a subwoofer needs to be integrated, you’d have to run the opposite phase to blend it in if you’re swapping from a different amp to these.

-Ed

 

[SMen]

I think I am now confusing myself. I posted over on the owner's thread about this.
Presumably if we test our v3 monos and find them out of phase we can just put the black into the red socket and vice versa - and then run the subwoofer as normal from pre-amp line outs. High level sums to mono anyway (with mine, if using one sub)

 

[antcollinet]

I think I am now confusing myself. I posted over on the owner's thread about this.
Presumably if we test our v3 monos and find them out of phase we can just put the black into the red socket and vice versa - and then run the subwoofer as normal from pre-amp line outs. High level sums to mono anyway (with mine, if using one sub)

Yes you can.

But I don't think there is a need to test - it looks like the Mono is inverting phase by design.

 

[SMen]

Yes you can.

But I don't think there is a need to test - it looks like the Mono is inverting phase by design.

There seems to be some confusion though - why would Fosi invert phase by design?

I can see no problem if I connect my subwoofers through the high level.

But If I was to connect to the RCA out on my pre-amp ... then that's where it is all getting puzzling!

Post edit: I'm a couple of months away from my subwoofers to verify - Hopefully consensus will be reached here regarding this problem or not problem.

 

[EddNog]

There seems to be some confusion though - why would Fosi invert phase by design?

I can see no problem if I connect my subwoofers through the high level.

But If I was to connect to the RCA out on my pre-amp ... then that's where it is all getting puzzling!

Conceivably something to do with PFFB architecture, or how they implemented that feature.

-Ed

 

[SMen]

Conceivably something to do with PFFB architecture, or how they implemented that feature.

-Ed

Above my pay grade ... but I'll look forward to understanding if I should be reversing connections if I want to run a subwoofer! Or how I verify.

I used to put speakers facing each other to test phase (sound waves cancel each other out so sounds quiet).