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Fosi Audio V3 op-amp rolling, has anyone tried it? Snake oil? Or are there actual differences?

I didn't hear any differences between OP-amps presented in that Youtube-Video too, But my ears. my system and/or the presentation on that platform might be lacking anyways... :)
It's everyones choice to "roll it" because of any subjective views anyone had about the results or just to make sure, it got the "optimum" (?), whatever this is supposed to be, audio setup.
But the manufacturers chosen (time proven) Ti NE5532 OP-amps might still be the right choice, I really don't know...
My opinion:
If one takes an OP-amp switch into acount, consider this a "budget" amp and chose a corresponding "budget" OP-amp, meaning spending less than appr. 10$ including an eventually needed adapter per item. Other items, like the speakers, have a lot greater influnce on the acoustical outcome...
 
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In any event, a YouTube video is hardly the place to hear subtle sonic changes :facepalm:
 
You've never had any tube gear before and while the JAN5725 pre amp tubes are fine you are listening via an s/s output that maybe not be anything like the optimum. Indeed the Philips amp also might not be operating at anything like optimum as it is an 'old' amp, any electrolytic caps might well need replacing. What model is the Philips, how old? If you are going to A/B then it's only really a valid test if it's an all valve amp of the same age and better yet of the same kind of initial value.
Philips FA950. On eye inspection there were not visible signs of any blown cap or anything similar. Of course that doesn't mean anything per se.

The fact I didn't hear other tube amps is a bit irrelevant here I think. If an amp produces a muffled sound that appears to be coming from the back of the room, behind thick layer of curtains I'd risk saying that it's not a good amp... Or maybe I know nothing and that's how all tube amps should sound like? (if so I'm definitely not going to be a valve lover and I can't understand how someone can be).

I came from a valve kit start - KT88/6550 power and full valve pre/phono/psu. There are lots of anti-valve 'believers' on this forum, I wonder how many have ever heard top flight valve gear.?
I'm not anti-valve by any means. Like I said above, I just didn't like the sound of the Aiyima T9 Pro.

Never forget that violins, acoustic guitars, cellos - hell all acoustic instruments and yes electric guitars are examples of listening to distortion.
Wait... what?!? Listening to acoustic instrument is listening to distortion? What do you mean by that? I'm sorry but that sentence doesn't make any sense to me, nor do I understand how you can compare electric guitars to acoustic guitars in terms of distortion.

We definitely have a very different definitions of what distortion means...

Anyway I've finally got the Fosi V3 and at first "sight" I'd say it sounds pretty similar to the vintage Philips amp. I've only listened to it briefly to it, so not enough to have a formed opinion yet, but at least it's definitely not night and day difference like it was with the Aiyima T9 Pro. Whether that's because of the valves or the rest I don't know, but I'd definitely rate the Fosi V3 way better than the T9 Pro.
 
There is this video on YouTube. I'm pretty sure I listened while watching the description of each op-amp so I'm certain my experience is flawed. I recommend you start the video and change your browser tab to something else while listening. Keep in mind that the setup isn't shown, it's made by the manufacturer of the amp who also sells the op-amps and it's on YT (compression etc.)

I'm not convinced anything is to be gained by swapping op-amps. I mean you can see the frequency response from the stock amp in the reviews.. Other good users have also provided measurements etc.

Anyway, here is the video-->
I'm sorry but listening to youtube videos (recorded who knows how) comparing the sound of different opamps is kind of meaningful IMHO.

I never understood this thing of people recording their audio system and them posting that on youtube... Even with very good mics and very good speakers on the listener side, there's no way you can somehow compare that to what the in person experience would be... That's not reproducible..

I'd expect the variance introduced by the recording process and the listeners gear is probably going to be a few orders of magnitude bigger than the actual difference cause by the opamp change (if any).
 
Thank you everyone for the comments. I've finally received the Fosi V3. I decided not to buy/try any other opamps. No comment in this thread made me believe that would be worthy attempting. And I don't believe that will/should be a factor deciding whether to keep the Fosi or not.

At first "sight" (listen), the Fosi V3 seems to be pretty decent. Compared to the vintage Philips FA950 I have as reference, it doesn't sound that much different (if any, but more listening required to be fairly sure). At the very least I can say it doesn't sound like night and day, like in my previous experience with the Aiyima T9 Pro.

I'll give it a few more hours of listening during the next days, but so far I think I can say the Fosi V3 restored some faith in the cheap chi-fi amps after my disappointing experience with the T9 Pro.
 
I'm sorry but listening to youtube videos (recorded who knows how) comparing the sound of different opamps is kind of meaningful IMHO.

I never understood this thing of people recording their audio system and them posting that on youtube... Even with very good mics and very good speakers on the listener side, there's no way you can somehow compare that to what the in person experience would be... That's not reproducible..

I'd expect the variance introduced by the recording process and the listeners gear is probably going to be a few orders of magnitude bigger than the actual difference cause by the opamp change (if any).
You are absolutely right but I knew the video existed and it's up to the OP amp roller to decide for himself.
 
I was using opa1656 with fosi v3 ever since I got the uni. Tried putting in opa1612 today. I felt a great improvement overall. Dynamics felt better, bass felt more defined and the upper midrange seems to have more air. Transparency got way better. Soundstage and placement felt more solid.

I would recommend trying opa1612 for people who havnt had a thought about it.

Thank you
 
You are absolutely right but I knew the video existed and it's up to the OP amp roller to decide for himself.
Thanks. I had seen the video before, but like I said such videos are meaningless to me, even less one published by Fosi, which wants to sell overpriced op-amps, so one can't even be sure if any possible differences heard in the video are actually due to any op-amp change or just some post-processing of the audio...

That's why I started this thread. I wanted to get some "real users" opinions, especially from this forum were (I believe) most people (or at least quite a few) are less prone to snake-oil claims and tend to put scientific facts in first place.

Not the case here, but I find it hilarious to see some people posting videos, recorded with their phones, of how great their new speakers sound... I wonder if they truly think others (most probably listening on their phones as well) will "experience" the same as them who are standing in the actual room with the actual speakers...
 
I wonder if they truly think others (most probably listening on their phones as well) will "experience" the same as them who are standing in the actual room with the actual speakers...
Unfortunately, I think they do.
 
I was using opa1656 with fosi v3 ever since I got the uni. Tried putting in opa1612 today. I felt a great improvement overall. Dynamics felt better, bass felt more defined and the upper midrange seems to have more air. Transparency got way better. Soundstage and placement felt more solid.

I would recommend trying opa1612 for people who havnt had a thought about it.

Thank you
Come back when you've compared blind, level matched etc, and been able to detect the difference reliably (at least 8 out of 10 times). Or measured the output of the amp and shown a clearly audible difference.

Otherwise most here will just assume you are (like anyone else would be) subject to expectation bias. :)
 
Come back when. you've compared blind, level matched etc, and been able to detect the difference reliably (at least 8 out of 10 times).

Otherwise most here will just assume you are (like anyone else would be) subject to expectation bias.
Agreed

However, it would be hard to design such a test... How could one do it ? The goal would be to instantly (and blindly) switch (or not) between op amps. These require physical intervention inside of the V3...
And having two V3 with a switcher would not be 100% decisive, as one could still argue that both units are not perfectly identical, aside from the difference in op amps

Is there a standard protocol for this ?

EDIT: It would be valid and "easy" doing as follows:
- Place opamp X in the V3
- Play a signal, and record the output with the necessary equipment
- Place opamp Y in the V3 (same V3)
- Same
-> Compare both recordings. Do an ABX with Foobar
 
However, it would be hard to design such a test... How could one do it ?
Valid point. as you say - two amps - then as you say - amp to amp difference. But if the effect of the op amp is in the same region as difference between amps, then there is not much point.

Recording the output might be valid but then you need to be able to record the high level speaker output with speakers connected.

In any case, not (IMO) worth the effort. Op amp rolling is never going to have the effects you describe, especially soundstage related. Best case you won't create an audible difference. Worst case you make the output oscillate. See the op amp rolling thread for more details.
 
Valid point. as you say - two amps - then as you say - amp to amp difference. But if the effect of the op amp is in the same region as difference between amps, then there is not much point.

Recording the output might be valid but then you need to be able to record the high level speaker output with speakers connected.

In any case, not (IMO) worth the effort. Op amp rolling is never going to have the effects you describe, especially soundstage related. Best case you won't create an audible difference. Worst case you make the output oscillate. See the op amp rolling thread for more details.
I did not assume any effect, especially when they are described with the usual audio-poetry, such as "better dynamics, bass more defined, airy midrange" etc etc.
Was just looking for a way for @nishamn27 to verify what he stated
 
Come back when you've compared blind, level matched etc, and been able to detect the difference reliably (at least 8 out of 10 times). Or measured the output of the amp and shown a clearly audible difference.

Otherwise most here will just assume you are (like anyone else would be) subject to expectation bias. :)
I have two units. Level matched to the best I could do with my ears. After that only I posted the review.

This group was way too friendly before to what I remember
 
I did not assume any effect, especially when they are described with the usual audio-poetry, such as "better dynamics, bass more defined, airy midrange" etc etc.
Was just looking for a way for @nishamn27 to verify what he stated
This is what I felt after comparing two units. If you feel it's wrong, just leave it. Maybe my ears are bad
 
I have two units. Level matched to the best I could do with my ears. After that only I posted the review.

Try matching levels with a multimeter. Also, if you know which is playing as you listen, that's going to get in the way of meaningful results as well.

Maybe my ears are bad

More likely your test methodology.
 
Try matching levels with a multimeter. Also, if you know which is playing as you listen, that's going to get in the way of meaningful results as well.



More likely your test methodology.
So you do mean to say there is absolutely no difference between opa1656 and opa1612 in actual listening terms ?
 
So you do mean to say there is absolutely no difference between opa1656 and opa1612 in actual listening terms ?
I think what he means is: to be sure the swap creates a difference, you need to test in a different way. Your current methodology could lead you to believe there is a difference when, in fact there is none.

Apart from this, why would the swap lead to better sound, and not worse (same with speakers/HP "break-in") ?
After all, the amp was designed around the op-amp it is sold with
 
I think what he means is: to be sure the swap creates a difference, you need to test in a different way. Your current methodology could lead you to believe there is a difference when, in fact there is none.

Apart from this, why would the swap lead to better sound, and not worse (same with speakers/HP "break-in") ?
After all, the amp was designed around the op-amp it is sold with
So you literally haven't heard any difference in swapping opamps?
I'm not talking regarding v3, infact in any of the designs which use opamps to make differential stage?
 
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