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

burkm

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Luckily, those points of view are subjectivly based on "opinions" of either side :)
As long as everone is satisfied by his personal choice I really don't care...
 

JSmith

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JSmith
 

SIY

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Luckily, those points of view are subjectivly based on "opinions" of either side :)
As long as everone is satisfied by his personal choice I really don't care...
Incorrect fact claims are not opinions. My statement was intended more for someone looking in so that they understand that this is make-believe, not actual electronics or sonics.
 

MaxwellsEq

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Luckily, those points of view are subjectivly based on "opinions" of either side :)
As long as everone is satisfied by his personal choice I really don't care...
You do not seem to know the difference between indisputable fact and opinion. If someone is curious and stumbles on this thread, here is the difference:

In your opinion, swapping op-amps can lead to things you feel are an improvement sonically. But you have not produced anything of any substantial value other than your opinion, which is just one opinion in several billion.

Fact: op-amps with different type numbers are different
Fact: differences may include DC, noise, compensation, GBW etc.
Fact: engineers design circuits to optimise for one specific op-amp type
Fact: different op-amp types need different optimisation strategies
Fact: swapping op-amp types means that a circuit is no longer optimised for the op-amp and vice-versa
Fact: the outcome is thus random, but since the optimisations no longer match, the probability is very heavily skewed to the result being worse, and at best, no better than the original.
 

Down South

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They're companies trying to make money, so I guess a wider variety of offers will attract a bigger audience...
"Audiophiles" have all sort of "audio fetiches". Some have the tube fetiche (here's a tube amp for you), some have the modding fetiche (here's an amp where you can swap some parts...) and so one...

I think the T9 is there just for those tube freaks... I never had anything with tubes so I thought I'd give it a try. It looked neat too. Got me sold initially... Sound wise? meh... So it went back (thank you Amazon for the great 30-day no-questions-asked return policy).
I'd like to try some "good" tube amp some day, but T9/T9 Pro definitely doesn't make the cut...

I also agree that tone control would be nice... But on the other hand I like the minimalism of it... hopefully means they had more time to focus on fewer design decisions and had more money to spend on fewer, but better components...
The T9 Pro was a hell lot of things in just one package... not surprising that it's not good at any of them...

I'll post back my thoughts on the Fosi V3 when I get it...
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.

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 ended up using hybrid valve gear, which I still have stored away. My initial reason to stop using valve/hybrid gear was living in a semi desert environment where serious static and 40C + summer temperatures in crap built property without A/C meant really hot operating tem ps. and a change to s/s gear. I ended up using preamp tubes that were an end game and if I can find a really well designed preamp where I can use the transparent Russian K73-16 caps and Z foil resistors using a Tung Sol 6F8G x 2 output Russian 1578 tubes into my Hypex power amp would be something to listen to.

Never forget that violins, acoustic guitars, cellos - hell all acoustic instruments and yes electric guitars are examples of listening to distortion. If your amplification doesn't mirror via speakers/headphones the distortion of live music - what exactly are you listening to?
 

BDWoody

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That probably is the reason, why each has his own impression and personal preferences considering this. All OP amps seem to have at least some sort of "audio" character of their own, allthough measurements don't seem to show this

If the measurements show there won't be an audible difference, so will listening tests when appropriate controls are used. Personal abilities or preferences aren't really relevant, if the basic claims made can't be supported with actual evidence.

I don't know, if everything of those stated "sonic" characteristics of the chosen OP amp are really exist, but many seem to believe in it, imagined or not.

Many believe in miracle spring water and homeopathy as well.

Neither "school" can prove their points ultimately, so you have to setup your mind yourself,

Well, since proving a negative isn't possible, we are left with those who make the unlikely claims to provide the evidence.

Can you prove I can't jump 20' high? I can, but I refuse to demonstrate it. I guess we are at a loss.
 

fpitas

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I've been designing with op-amps my whole career. I would hesitate to just toss in another op-amp if I had a working design. I'd certainly do extensive testing afterwards. Doing that with someone else's design is even more fraught, especially with high-speed op-amps. It may be fun and inexpensive, but:

1. I doubt you'll make an actual improvement, and
2. You may create an oscillator.

But you won't burn down the house or harm anyone. So knock yourself silly.
 

fpitas

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Never forget that violins, acoustic guitars, cellos - hell all acoustic instruments and yes electric guitars are examples of listening to distortion. If your amplification doesn't mirror via speakers/headphones the distortion of live music - what exactly are you listening to?
Wait...are we arguing you should just pile on more distortion on playback, because (for example) Hendrix' guitar amp makes 30% THD?
 

SIY

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Never forget that violins, acoustic guitars, cellos - hell all acoustic instruments and yes electric guitars are examples of listening to distortion. If your amplification doesn't mirror via speakers/headphones the distortion of live music - what exactly are you listening to?
No. Harmonics are NOT distortion, they are a component of the original signal. And if electronics have low distortion, those harmonics will be reproduced faithfully.

I ended up using preamp tubes that were an end game and if I can find a really well designed preamp where I can use the transparent Russian K73-16 caps and Z foil resistors using a Tung Sol 6F8G x 2 output Russian 1578 tubes into my Hypex power amp would be something to listen to.
Personally, I prefer listening to music, not to preamps.

If exotic caps and resistors are your fetish, great, but fashion stuff won't work in audio circuits any better than appropriately chosen (and vastly more inexpensive) mass-produced parts. And very often, not as well.
 

fpitas

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Harmonics are NOT distortion, they are a component of the original signal.
Exactly. Even if they were purposely generated during the performance.
 

Down South

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No. Harmonics are NOT distortion, they are a component of the original signal. And if electronics have low distortion, those harmonics will be reproduced faithfully.


Personally, I prefer listening to music, not to preamps.

If exotic caps and resistors are your fetish, great, but fashion stuff won't work in audio circuits any better than appropriately chosen (and vastly more inexpensive) mass-produced parts. And very often, not as well.
Siy the Russian Caps were as as cheap as chips. There was an excellent thread on diyaudio all about these Russian mil/spec caps. Like a lot of others I was skeptical about this thread started by a London based medic who had shelled out plenty for exotic expensive western made caps and then found these.

So I bought some and tried them. I was really pissed off because just prior to these I had been persuaded by my Dutch friend Harry to spend plenty for some hand made Dutch silver foil caps. Those silver foil caps were good but the Russian caps were like the Vishay Z foils - transparent.

So no one could describe the mil/spec caps as exotic and the Z foils have superb operating specs. You hav'nt tried either so your opinion is based on unproven bias which is not scientific.

On that thread it got polluted by a few narcissists who knew they were 'no good' but had never tried them and that all those who had tried them were fools and worse. I never comment on products or components that I have never tried. Describing mil/spec caps as 'fashion stuff' is really stupid, they were ludicrously cheap to buy, you sound like one of those American bible thumpers - only you have the truth - very unscientific.
 

Down South

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I'm neither for or against valve or s/s gear. If I want to listen to ambient or electronic music then s/s has to be the best. I watched a film on French TV the other day - Brooklyn Affair set in the 1950s. It wasn't a bad film but the music was for a jazz lover incredible. Absolutely my kind of jazz. A good system to listen to this kind of jazz would have to be valve, no question but then I'm speaking from experiencing both valve and s/s. I get the distinct impression that many who are contemptuous of valve gear are quoting from theory a bit like religious or political freaks - 'who know they are right'. If you have actual experience of quality valve and s/s gear fine then your opinion is as valid as mine.
 

BDWoody

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Like a lot of others I was skeptical

Well, that's certainly reasonable to be skeptical.

Those silver foil caps were good but the Russian caps were like the Vishay Z foils - transparent.

Can you describe the controls used for these comparisons, if any?

I never comment on products or components that I have never tried.

How well do you understand the measurements done and circuit design or electronics in general? Can you share any schematics of any projects you've developed?

If you have actual experience of quality valve and s/s gear fine then your opinion is as valid as mine.

Well, SIY certainly has that and more, yet you seemed happy to dismiss his thoughts.

You are bordering on trolling behavior here, with a lot of very confidently stated nonsense and a bit of an aggressive tone thrown in for good measure. You'll need to dial back if you want to stick around.
 

burkm

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If the measurements show there won't be an audible difference, so will listening tests when appropriate controls are used. Personal abilities or preferences aren't really relevant, if the basic claims made can't be supported with actual evidence.



Many believe in miracle spring water and homeopathy as well.



Well, since proving a negative isn't possible, we are left with those who make the unlikely claims to provide the evidence.

Can you prove I can't jump 20' high? I can, but I refuse to demonstrate it. I guess we are at a loss.

Unfortunately, neither side can "prove" anything, because human hearing is tied expressedly (and knowingly) to the indivual person "hearing something" although it might not even exist. Additionally ones brain is heavily envolved into that individual "hearing" situation and interpreting it according to its own believes. This might lead to imagening things which don't exist in reality.
It cannot be measured like an instrument, what really happens on that front. But: We don't even know, if everything we seem to "hear", can and is been "measured" relevantly and completely relating to that subject because of those "phenomenons" and - as a result - many people come to different conclusions / impressions on the same subject.

We naturally can "religiously" discuss our point of view without getting any closer on the subject, don't we... :)
 

BDWoody

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Unfortunately, neither side can "prove" anything, because human hearing is tied expressedly (and knowingly) to the indivual person "hearing" something

Of course they can. What are you talking about?

If I claim I can hear something, there is a way to prove I am hearing it. It involves using controls.

Not sure why you think sensory claims can't be validated.
 

SIY

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Siy the Russian Caps were as as cheap as chips. There was an excellent thread on diyaudio all about these Russian mil/spec caps. Like a lot of others I was skeptical about this thread started by a London based medic who had shelled out plenty for exotic expensive western made caps and then found these.

So I bought some and tried them. I was really pissed off because just prior to these I had been persuaded by my Dutch friend Harry to spend plenty for some hand made Dutch silver foil caps. Those silver foil caps were good but the Russian caps were like the Vishay Z foils - transparent.

So no one could describe the mil/spec caps as exotic and the Z foils have superb operating specs. You hav'nt tried either so your opinion is based on unproven bias which is not scientific.

On that thread it got polluted by a few narcissists who knew they were 'no good' but had never tried them and that all those who had tried them were fools and worse. I never comment on products or components that I have never tried. Describing mil/spec caps as 'fashion stuff' is really stupid, they were ludicrously cheap to buy, you sound like one of those American bible thumpers - only you have the truth - very unscientific.
On my website, you'll find some pretty comprehensive measurements of fashion caps versus cheap Radio Shack parts.

If you have cites (or data) to listening tests done with basic ears-only controls which contradict basic engineering and measurement, please let us all know about them.
 

SIY

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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-->
 
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