Get the tube sound in your system with the Fosi Audio P3

[@edwardallan197]

I am using a cheaper one without BT, tone pots. I love it. I can tell a difference in many small ways. Wired into a tape monitor loop. Bass detail, presence of piano & female vocal come to mind.

[@EgoShredder]

Thorough review although you neglected to perform the necessary audiophile spell casting ritual, to properly align the valves with the galactic frequency aura for maximum playback quality and pleasure.

[@thinkIndependent2024]

Funny but without someone with Audiophile level hearing nothing works!! all aspects Including equipment calibration . True story I once laughed at those with seasonal allergy. Until I developed them myself.

[@EgoShredder]

@@thinkIndependent2024 I'm just having a laugh. I own equipment considered pro studio grade and audiophile as well. I can hear the differences between things, and I even own some valve preamps although I do not use them in the signal path for the audiophile stuff. I reserve that for microphones and guitars. Yeah allergies are no fun and can make you feel ill and debilitated all year round.

[@RocknRollkat]

Hello DM, Nice demo, I heard no difference, -70 dB is not enough distortion to make a difference to my ears. I built a plugin that gives nice results at -60 and -50 dB. distortion. Bass is to 'boomy' for my taste, treble doesn't do much. But that's just me. The box does what it does, if that's what you want, go for it. Bill P.

[@wadimek116]

Honestly aiyima t9 sounds awesome from my experience to. Those amps are awesome, you probably don't need anything more than those cheap chinese amps. I prefer the d classes but I had full satisfaction with them

[@c1bav]

You can unscrew the orange valve covers to fit the valves easier

[@ConorHanley]

So much for reading the manual and I've watched a handful of reviews and only one figured out the unscrewing while a few complained about the difficulty of tube-rolling.

[@MarkThomas-hm3ju]

It probably uses op amps so there is no transformer to drive the tube section. I believe the tubes are used to color the signal. Probably still has some good qualities.

[@AudioMasterclass]

I will have more to say about these tubes in a future video.

[@ggroch]

The headphone output on the P3 uses an HT97220 headphone amp chip, which is not of course used in the rear line outs. So, they will not sound exactly the same. I am not even certain the headphone out runs through the tubes. Have you tried to see if the headphone output works when no tubes are installed?

[@AudioMasterclass]

I checked all three outputs and there were harmonics present in all. As for tubes-in vs. tubes-out, this will be covered in a future video.

[@kevinmcgrath3591]

at 5:45 you mention headphones + Sub woofer - can you do a show on this please, Ive thought about doing just that, never did, thanks, great videos !

[@Amplified208]

That is a nice-looking unit and does sound pretty good. But I'm a solid state guy and like the look of the tubes but not the sound.

[@AlexMitchell-sj4sb]

I liked your music by the way, very mellow.

[@AudioMasterclass]

Thank you for that. I originally wrote it for my Beer52 (www.beer52.com/) unboxing. That might be the reason for the mellowness.

[@Mk-tp2mz]

Am concerned that blue component in your lighting may colour the sound by inducing In high frequency interference in to the wiring, would recommend operating within a Faraday cage. And dimming the lights to achieve maximum performance.

[@avranx]

Hey thanks for review. I wonder how many db it is when the bass and treble knobs are in the center position? 0 db or +3 db? I mean, when I turn the knob to the - side, does it become -db? I want to know.

[@BostonMike68]

Very informative. I purchased a Dayton audio hta 200 tube hybrid with a ab power amp and a tube pre amp . Its ok for chi fi But i wonder if the tubes are more of a gimmick .

[@paulstubbs7678]

It would have been good if he tried pulling the tubes to see if the sound stopped - i.e. they are actually in the audio path.

[@BostonMike68]

@paulstubbs7678 on my Dayton they are definitely in the audio path of the pre amp but how much it effects the sound idk but it looks cool and I got it at a big discount so I have it in my collection

[@TobyIKanoby]

I only hear a difference in the lower frequencies, but might just be because I have been tuning 30 to 500 Hz all day.

[@ac81017]

I'm on the look out for a early 70's Vibrolux, supposed to a fantastic studio amp?? Can we have a link to your hit single on Spotify please?

[@DrBovdin]

Are these Fosis not more correctly defined as “valve attenuators and harmonic distortion adders”? Last time I saw a tear down of one, it turned out the valves were merely buffers, and actually attenuated rather than amplified the signal. The actual amplification was done by standard solid state OP-amps.

[@AudioMasterclass]

I'll have more to say on this item in a future video.

[@DrBovdin]

@@AudioMasterclass Great, looking forward to it 🙂

[@msingh1932]

I couldn't tell any difference in quality. I am going to fall back on the Master's advice in video....Audiophiles (which I am not!) you are wasting your money!

[@ConorHanley]

Have a few amps with tone controls and whenever I've used them I always end up in neutral or bypassed. They have an effect obviously but not anything I find useful. Is that the norm or am I an outlier?

[@AudioMasterclass]

I might possibly address this in a future video but if you don't feel the need for your tone controls then just don't use them. If you can switch them out then so much the better (in theory).

[@AudioMasterclass]

Well you could tweak them to get the best sound across all, or at least most, of the music you listen to. Or you could switch them out and tune in your ears to the sound you're getting, which will be dominated by your speakers and your room. I may make a video on this topic at some point.

[@johnathenbates2929]

@Audio Masterclass, Sorry if I misunderstood but those aren't light bulbs, they do the job of transistors! It's what they used before the transistor was invented! I hope I'm not being affected by subliminal affirmations but I feel the need to comment on a couple things you know! Yeah, those compact amps are pretty neat!;)

[@fiddlix]

The sweat on your fingers is an urban myth @ best as far as it pertains to affecting tube life. Hog wash is what I call it lol.

[@SileDevil]

thanks for the demo but theres hardly any difference

[@mephitusincognito7918]

not a fan of the harmonics it adds (yes i can hear them) and whatever weird thing its doing to the high frequencies.. i knew tubes were noisy but not THAT noisy...

[@TuffyAndBetty]

I bought the P3 to feed my Antique Sound Labs Wave DT 8.5 Watt mono amps. I was using a passive preamp which I found lacking and felt it needed an active preamp. The P3 give the sound extra “juice”. The vocals are better articulated where you can hear the lyrics more clearly. The voices and instruments have more “space” around them making everything more distinct. Soundstage has more depth. Can’t say the sound is more “tubey” with the P3. It just bring more clarity to the music. I have much more expensive Primaluna tube pre and power amps but I can enjoy the sound of my more minimalistic system too. Can’t beat the price!

[@nickbdy]

Excellent review, with actual auditory and visual examples of how it would sound (via KZbin, on my iPhone and out of my AirPod Pro 2’s). I heard a drop in the higher frequencies (the beep bit of the music) on the Fosi compared to the original.

[@gillesthibodeau7078]

I use white cotton gloves to manipulate tubes! ;) Nice review!

[@andrewbolam4346]

I can hear a slight rounding of the transients and a little bit more 'grit' in the tone itself, but it is very very subtle in the demonstration, you really have to listen intently. I think it warrants investigation if not a purchase, as the tone controls offer a lot of variety to my ears.

[@teamsix7185]

Without a doubt the best channel on KZbin for true informative value audio information (feel free to use that term). I am unsubscribing myself from my other audio channels. This channel has a hugely bright future. David you are brilliant.

[@paulyounger6839]

Fantastic review - love the delivery and the content - more engaging and informative than other audio 'tubers. Keep it going!

[@anthony2010707]

Have this P3 connected to a V3 at work, broke two tubes but the sound from these amplifiers is really nice coming through my Q Acoustics 3010i speakers.

[@mikecampbell5856]

I have a Fosi Audio P1 and was going to use it as a tube buffer. I put in a tape monitor loop and with my remote I could instantly switch it in and out. I couldn't hear any difference. It has tone controls so I turned up the bass and had a loudness control.

[@geoff37s38]

Why would anyone wish to add distortion? Do the tubes actually do anything, or are they added to fool the technically illiterate? What happens if you remove the tubes, dose it still work?

[@alwilliams5177]

Euphonic distortion is a beautiful thing. LED's aside the tubes do have a little gain and get warm. Macintosh sound? Of course not. Better than straight class D? Definitely. fossi makes great gear for those of us who will never have the chance to spend $10k on audio gear. If you think solid state is always superior, don't listen to tubes.

[@boblaws7582]

Just a thought, what would you think of building a Hi-Fi system based around the Fosi Audio range of items currently on sale, for example the K5 Dac, P3 Pre-Amp and V3 Amp? And what speakers would you recommend to produce a smooth detailed sound (without breaking the bank)?

[@ianpearson8976]

some thing vintage from the 80s ,far better sound that todays stuff and very cheap alot of it on fb marketplace.

[@gregbailer8701]

As a pro musician since 70's I appreciate your industry experience. We made music on 4/8/16-tracks of analog tape. The same recordings that modern audiophiles argue about 16/24 or the release date of vinyl pressings. Many say "With my system. it sounds like the band is IN the room". Trust me, Neal Peart's drums would not fit between your speakers.

[@ericksonengineering7011]

Thanks, great review. I'm impressed that an open-loop (no feedback) tube circuit can do -70dB distortion. Maybe it has feedback? But as others noted, the distortion has little or no no audible effect at that level.

[@rotaks1]

Thanks for the review. I went ahead and purchased one. How do you propose I pair it with the V3 in terms of both units having volume controls. Should I tuen the V3 all the way up and control volume using the P3's pot or is there some other way? Thanks!

[@marxman00]

I prefer a pair of Tube Screamer fuzz boxes as a pre amp , as winter looms ,its so much "warmer".. more of a wasp in the room than an elephant in the room. I think its the warmth of the Bluetooth shining through here

[@CORVUSMAXYMUS]

AMAZING, HIGH IN DEPTH TECHNICAL AND LIVE DETAIL.THANK YOU AND GREETINGS FROM ROMANIA.

[@ianpearson8976]

i use the fosi p1 with aiyima a07. this runs spotify through some mission 6 speakers.sounds pretty good.

[@vaporizer1000]

tube sound it is something which is not everyone can understand. in many places talking it like about most important thing ever but it is not. about richness of sound i guess it is not. it is good for violin but even there is not most important thing ever. it is not common thing for using even for people who already have it. and you need very good tottal quality of sound system to feel any profit from tubes, it is not like for headphones as my opinion. just only for some people who really believe in tubes.

[@PaulLodewijk-dc7xq]

Hello great review. You can twist the orange rings out of the P3 and have more room to put the bulbs inside the sockets.

[@AudioMasterclass]

Possibly a good tip for tube rollers.

[@c1bav]

Great to drive some active speakers and have tone control

[@NeverTakeNoShortcuts]

But I’m an “audiophile” I can hear inaudible differences you peons can’t.

[@richardmarkham8369]

Just wondering why they didn't put balanced xlr outputs on this, making it a nice companion to the Fosi Power Amp...?

[@AudioMasterclass]

I get the impression that the people at Fosi read KZbin comments. Maybe you'll get your wish; I'll certainly review it.

[@schawinsky]

Its just marketing

[@peterdavies5358]

A few years ago I bought a self-assembly kit for a Chinese valve headphone / preamplifier. I've got to stress that this was in no way connected to the product that's you're testing here. There was no connection whatsoever besides them both using valves. I never actually got round to building it because once I looked into the circuit I realised that the valves were not in the audio path. They were purely decorative. One test that I really like is to record the output and then reverse the phase so that playing the original and the recorded output together you get to hear just the difference.

[@paulstubbs7678]

Thanks, you've just solved my 'no valves in my stereo' problem... I have a few tubes mounted on a block of wood, I'll just toss them into the rack and it will have all the valve sound of that kit - Zero. Perfect valve sound, with zero audio degradation. Maybe I'll add some LED illumination to exaggerate the lie.

[@graemejwsmith]

Ha ha - yes. My comment was to try the amp with the tubes out and make sure they were more than decorative. That tiny power supply must struggle to provide the power necessary to drive those tubes. The Fosi website claims "The preamp circuit elevates the voltage to 54V, ensuring the tubes work to their full potential" (wonder if they meant that pun?) The spec for that tube is for a plate and screen voltage of 120 V and grid voltage of 2.0. If it is doing anything - at 54v it is pretty under driven - using Fosi's numbers. Some of those earlier designs - as you note - the tubes do nothing. The con artists have cottoned on to that now - using the pins and the heater element in the tube to make part of the circuit. And make the valve glow and warm up. But they don't actually contribute to the amplification. But when you take the tube out - the amp stops working - so it must be doing something. Right? But bridging the heater pins in the socket with an appropriate resistor restores functionality.

[@JorgedeLumiarFerreira]

Great review. Your method is refreshing and definitely stands out from all the other Hi-Fi reviewers out there. Real, engaging and helpful. Congrats.

[@DonnieMulligan]

Great Stuff! Keep the reviews coming. Topping and Aiyima have comparable offerings.

[@easyphotoshop1264]

No remote for this unit ? For get it about it

[@AudioMasterclass]

Cry cry cry.

[@paulstubbs7678]

Interesting, on the tone test I could hear the added noise using my monitor speaker, but not with my headphones.. My current headphone amp is a DX200USB mixer desk. I'll try another amp and come back for another listening session. That said, I'd much prefer it if they provided something to protect those fragile glass envelopes.

[@pavelpavlov954]

I am listening on an NS-10's and fosi sound a bit "forced" and grittier although not by a big margin.Might depend on tube bias or the particular tube model.. Anyways great review!

[@stefanweilhartner4415]

did you use a usb-audiointerface like audient, focusrite or SSL to do the noise/harmonics measurement and 220Hz generation? for me, the difference between the original and the fosi was ausdible - just about. the original had more dynamic in the lower mids. the fosi was a bit muddy, losing detail in the lower mids. also i am not 100% sure if the channel separation was slightly impaired. that is not covered by your measurements.

[@alswearingen323]

Seems a rather silly idea. I've a tube microphone and a hybrid amplifier with tubes which seem to work rather well.

[@Antoon55]

I prefered the original sound. I like tube distortion in my guitar amps though but that's a whole other level of distortion.

[@bukeksiansu2112]

I have Fosi Audio P1since 2021, the sound is good enough for my ears (I'm not audiophile).

[@mortenjohansen4120]

Why rhe annoying background music?

[@absolutekarl]

Ha ha ... no I don't listen to headphones with a sub connected, but I DO "shake" an entire 4m x 5m floating concrete floor with a tactile transducer (heavily processed with deep notches to negate resonance, frequency dependent compression, phase correction and time alignment) !!!. The listening experience is nothing short of amazing ............

[@AudioMasterclass]

Comment readers might think he's kidding but here's a thing... thebuttkicker.com/

[@davidkclayton]

Not enough difference to warrant the fuss.

[@shipsahoy1793]

Seems a little out of character for Dave to be reviewing some cheap toy like this. Not sure what that’s all about. I’d hate to see Dave pollute his channel with these low grade solutions. There are plenty of less knowledgeable audio guys on KZbin already covering this type of stuff.

[@jimfarrell4635]

It's inaccurate to call this a toy. It's simply an ultra budget component which is entirely adequate for desk top systems and is not embarrassed in a small room with its companion amp, the V3. What it is, is value, and a way into hifi for folks who may not have the disposable income to spare on expensive gear. Deriding it as a toy is patronising nonsense and exactly the kind of thing which gives audiophilia a bad rep.

[@lenimbery7038]

@@shipsahoy1793 Isn't Dave being just sarcastic with this whole post? A cheap piece of junk that does little or nothing yet he gives it a go with an actual review which I took to be all tongue in cheek

[@shipsahoy1793]

@@lenimbery7038 Interesting angle; I wasn’t sure where Dave was going with it. That’s the only reason why I brought it up; the other guy that commented on my post doesn’t seem to understand that when it comes to hobbies, it’s essentially all toys.. if you make money with equipment, then it becomes tools; it wouldn’t matter if it was a $2000 preamplifier, it’s still a toy if you’re not making money with it. . I’ll never understand those hypersensitive types.

[@Exgol2005]

quite an earful and loadfull informative. Masterfully done!!!

[@graemejwsmith]

Did you test the "true tube" claim? Take tubes out- does it still work? Lot of these small tube amps - the tubes are only for show and don't do anything except look pretty..... -- If the tubes ARE doing something - did you burn them in for about 30 hours before testing? You should get quite a different result.

[@AudioMasterclass]

Don't worry! I'll be testing tubes-in vs. tubes-out in a future video. Burning in too will be a fun topic. I foresee an avalanche of comments.

[@graemejwsmith]

@@AudioMasterclass That tiny power supply must struggle to provide the power necessary to drive those tubes. The Fosi website claims "The preamp circuit elevates the voltage to 54V, ensuring the tubes work to their full potential" (wonder if they meant that pun?) The spec for that tube is for a plate and screen voltage of 120 V and grid voltage of 2.0. If it is doing anything - at 54v it is pretty under driven - using Fosi's numbers. Some of those designs - the tubes do nothing. The con artists have cottoned on to that now - using the pins and the heater element in the tube to make part of the circuit. And make the valve glow and warm up. But they don't actually contribute to the amplification. But when you take the tube out - the amp stops working - so it must be doing something. Right? But bridging the heater pins in the socket with an appropriate resistor restores functionality.

[@Level42Man]

Tubetastic Review 👍🏻

[@frogandspanner]

I am developing an adaptor for TVs with 405 and 16 mm switchable options. In TV mode it will reduce the resolution to 405 lines, and simulate lack of black level clamping, for that authentic 1950s grey cast on dark scenes. In Film mode it will introduce grain, vertical scratches, and short-and-curlies stuck in the gate. It will be wonderful to couple it with one of these valve amps to demonstrate how much better things were in the days of the horse and cart.

[@AudioMasterclass]

If you develop your adapter as a plugin for Final Cut Pro, Premiere Pro etc you will become rich.

[@enricoself2256]

It would be interesting to check the schematics of this headphone amp: I have seen reviews of "tube" headphone amp where the tubes were basically just more extravagant led's completely cut-off from the audio path which was managed by a conventional integrated op-amp. Sure the level of distortion might suggest the tube are actually used in the audio path in this amp: a properly designed solid state headphone amp would not have that kind or harmonic distortion.

[@AudioMasterclass]

I'll be making a video soon where I take the tubes out. I wonder what will happen.

[@DeltaJazzUK]

I thought you didn't buy into the audiophile valve thing ( I refuse to adopt your Americanised 'tube'). After all, if an amplifier changes the sound, it's no longer just an amplifier but an effects box as well.

[@AudioMasterclass]

In my reality, thermionic tubes exist in microphones and guitar amplifiers, and maybe compressors. But I don't mind having a bit of fun with them now and then.

[@mariokrizan399]

👍👍👍👏👏👏👏👏

[@eancurtis9333]

Definitely a thicker sound..why is 220 hz your favorite ??

[@iikatinggangsengii2471]

no he1 is

[@fofocho71]

How is the sound compared to Fosi P1 (stock tubes)? Thanks

[@AudioMasterclass]

I don't have the P1 but if one turns up I might compare it.

[@lucasrodriguez8957]

Why the tube amplifier have some kind of white noise in the harmonic demonstration? I apologize in advance if it is a stupid question, I'm new to the scene.

[@AudioMasterclass]

There's noise everywhere in electronics. It just needs to be low in level. The noise here, if you look at the spectrogram, is way down in level. If you can hear it, then your ears are very sharp.

[@lucasrodriguez8957]

@@AudioMasterclass Thanks for answering my question. You videos are really entertaining and educational. Don't know if I should feel good about being able to hear the noise then, I would prefer not to 😂

[@AG-bp3ll]

I picked up one of these based on this review, but it was not possible to insert the tube in the left side. Both tubes would fit fine on the right but no matter how careful I was, inserting one on the left side would bend half the pins. They are not easy to straighten back out either. I'm assuming something is misaligned and will return it for another. Hope this isn't something common.

[@AudioMasterclass]

I think there is probably an art to inserting tubes. Whenever I've done it, including for my guitar amplifiers, I'm always thinking "don't bend the pins, don't bend the pins". I never have. So far.

[@m.vimercati301]

Maybe it is my sytem but to my hears when fosi modulated the sound of your sample becomes veiled.

[@superd222tube]

Same, ever so slightly. Not sure if it was my ears or eyes.

[@steven2809]

@@superd222tubeProbably your brain....😂

[@EgoShredder]

I'm more of the opinion that valves have their place in the music creation process, but once that is done I prefer the playback of the finished masters and digital formats to be without valves as it just somehow messes things up. I do love valves though for guitars and vocals etc during tracking and mixing etc. The implementation on the Fosi device seems badly done IMHO and I would prefer to not use it.

[@schemkesa]

Great unboxing video😂😂😂, but thats not what I'm here for.... 😉 very curious about the sound/distortion... 😅.... well I listened very carefully, but couldnt hear any difference. Guess I'm not a Audiophile... 😢

[@bluesfish55m51]

You should be happy. You won’t have to swallow that nasty snake oil or waste time burning in your cables. 😂

[@tree-of-lies537]

My friend bought one of those. It had a free membership to the Chinese Communist Party with it and a thanks for the damage he did to his own countries economy. Did yours?

[@maidsandmuses]

I can hear the added distortion clearly; not a fan of it. For some reason the treble control to the left and bass control to the right of the volume control feels the wrong way around; maybe that's just me... Headphone amp output impedance should not _necessarily_ be as low as possible; some older headphones were specifically sound-balanced to be driven from a standard 120 Ohm output impedance according to IEC standard 61938. This is an outdated standard and nowadays zero Ohm is a better choice, but some older headphones sound more neutral with a 120 Ohm output impedance. I believe Beyerdynamic notably held on to this standard longer than other manufacturers did.

[@peters7949]

I’m with you on tone controls, in my mind, low freq on the left, high on the right. Not that is really matters, they are always set flat on my systems.