Killingbeans
Major Contributor
Maybe he has working ears ....
Or just a normal human brain, that naturally loves to superimpose experiences with the things it expects
Maybe he has working ears ....
Isn’t it more old vs new??? So old is the picture on top?Here is a photo from the Fosi FB group that shows new vs old.
They just reversed the output wires to the speaker terminals.
Shockingly bad soldering quality though. Clearly modified by a person who has. no idea how to do it.I just received my six V3M amps today and I can confirm they have all been updated (output wires switched). I had the cycle time for checking down to four minutes after doing it six times! I'm using the RCA inputs on my HT system, and I don't have a clue if they are in phase or out of phase but at least they are all the same. They sound just fine! Have to do some wire routing...
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But I am actually an Engineer and quite knowledgeable on how to set up a valid test…Because engineers aren't good at predicting how easy it is to make non-engineers confused
@Stoutblock tested his old units (and that he would check his six new units as well). And AFAIK up till Fosi's latest testing post, we had no one else that had tested the new units (and no "I got my reworked units and they sound okay" does not count). Until I saw Fosi's confirmation of new unit actual measurements, I was simply seeking the truth, sorry you took this as negativity.Hang on. Fosi has said rca and xlr are the same and there was a post earlier where someone tested it and agreed. I don’t understand all the negativity. It was the same when there was a thread panic about heat.
Phase issues with speakers are typically easy to hear by a/b comparison. If it isn’t audible at all to the listener because one speaker is a sub then perhaps the polarity difference isn’t all that important.
That was on old units, and he was going to test (6) new reworked units when he (@Stoutblock) got them. He has rec'd those, awaiting a non-Fosi confirmation on new units, that speaker polarity does not change with input selection.There's literally a video demonstration by a member in this thread showing the phase is exactly the same on XLR and RCA inputs.
THISI care less about correct phase and more that RCA and XLR are the same.
But I am actually an Engineer and quite knowledgeable on how to set up a valid test…
Fosi has said on more than one occasion that rca and xlr are the same polarity yet some posters have remained suspicious and that seems like unnecessary negativity to me. Perhaps it is a need for reassurance given that Fosi is at the more affordable end of the market and a new brand to many.@Stoutblock tested his old units (and that he would check his six new units as well). And AFAIK up till Fosi's latest testing post, we had no one else that had tested the new units (and no "I got my reworked units and they sound okay" does not count). Until I saw Fosi's confirmation of new unit actual measurements, I was simply seeking the truth, sorry you took this as negativity.
Also sorry a few posters here trying to explain proper sub integration to you is explained away by its an easy a/b comparison and perhaps it isn't that important, if one has dabbled in LF phase audibility and LF in rooms and shaping it via sub(s) one can see it is important indeed. Grimani has some excellent material on this if interested.
Nonsense, power is power independent of the “nationality”.If a Chinese chipamp doesn't have enough power, get a proper Hypex or Purifi based amp. No surprises here.
Judging from the looks of some wiring solder joints that I have seen yes there could be a loose wire end floating inside. I think under the circumstances it would be prudent to return the unit without opening it. Play the long game on this stuff. Long being days...If I shake the V3 mono that failed, I can hear something moving a bit inside. Not like a completely loose component, but more like a wire that is connected on one end and not the other. Could be that one of the solder repairs they did came loose when I disconnected and reconnected the RCA inputs. I'm tempted to open it up to see what it is, but since I already have the return set up for Monday, I am resisting that.
These were mend to be opened.If I shake the V3 mono that failed, I can hear something moving a bit inside. Not like a completely loose component, but more like a wire that is connected on one end and not the other. Could be that one of the solder repairs they did came loose when I disconnected and reconnected the RCA inputs. I'm tempted to open it up to see what it is, but since I already have the return set up for Monday, I am resisting that.
The picture is not intended to prove anything. It is simply provided to demonstrate how, and that, they have done the test.If Fosi wants to prove that the new amps have the same and correct phase for both XLR and RCA, why not show two identical production units with the only variable being RCA vs XLR input?