Which Rocks? Fosi Audio V3 with Various Op-Amps Demonstration

[@hyperion7772]

NE5532 is the best by far : clearer, more natural, more balanced. The amp was designed to use this chip, so it gives the best results. A preamp stage is a global circuit including the opamp and side components calculated to run the opamp with it's own specifications. There's a good reason why most manufacturers use this opamp since years : it was designed for audio reproduction and even pro-audio studio high end analog devices keep using it with nothing to do with cost.

[@66hats]

Its my favourite in this demo for sure

[@beprotishen]

No details at all

[@ItsMe-mq9tp]

@@beprotishen your ears

[@marktwain2813]

Agreed 👍🏼

[@MiguelAngelVelazquez]

My only recommendation is to play exactly the same track portion for each opamp. That's the only way to clearly compare them. Multiple passages of the song have different sounds, notes, instruments and effects.. That makes it harder to compare them.

[@Panslapper]

I agree, it’s very important that the same piece of music is used as this is where alot of reviews fall short because it doesn’t fairly or clearly show the strengths and weaknesses of the products in comparison.

[@crazyprayingmantis5596]

Exactly what I was going to say, it's a no brainer really, audio companies shouldn't have to be told by us dummies they should know.

[@Douglas_Blake_579]

@@crazyprayingmantis5596 Trust me... they know... and the competent ones are using test equipment rather than listening sessions. Even a hobby level oscilloscope can show them more than their ears will ever detect.

[@emptywig]

@@Douglas_Blake_579 I don't care what the oscilloscope says. I listen with my ears, not a scope.

[@Douglas_Blake_579]

@@emptywig Okay ... if that's what you want. I'm not going to twist your arm. But, as one who both tests and listens, I do know exactly what you are missing.

[@ianhames2465]

NE5532 is a bipolar transistor topology which has even order harmonics, where the OPA2604 is a FET (field effect transistor) topology which has odd order harmonics. The sound presentation can also be effected by the voltage supply to the op-amp, as in the case of the NE5532 where it sounds best when a 9V +- supply is used as opposed to say a 12V +- supply.

[@daddymao2944]

I think it is that FETs produce more even harmonics as BJTs have a non linear relationship with their input/output while FETs are square law devices, meaning (in a simplified manner) that their output is their input squared, these OP amps are wired as differential amplifiers so you probably won't get any audible even harmonics and very low odd but FETs will still intrinsically sound more like tube triodes/pentodes than BJTs

[@ScottGrammer]

It's not the choice of FET's or bipolars that decides whether more even or odd-order harmonics are generated, it's the topology - that is, the layout of the stages - that determines that. And as most op-amp circuits have 60-100dB of NFB wrapped around them, it really doesn't matter, as distortion is cut to VERY tiny percentages.

[@makamancha2333]

For average Filipino room, the one that gives a better sound stage is the winner for me and I go for NE5532.

[@Jil8840]

The only that I like.

[@zoroastofelix]

For me the best too

[@66hats]

Based on this demo, it was the best

[@ricsim78]

NE5532 is a good all around OP AMP, it does everything right. I would hardly call it the best, it's good but not exceptional. Sparkos has the best OP AMP I have heard to this date.

[@michaelwright1602]

I installed the Sparkos, and the sound became veiled, and the bass was a bit muddy. I reinstalled the factory op amps.

[@ramondelgado6778]

Thank you!

[@jeanmichel2642]

as the NE5532 was the industry standard for pro audio during last decades, there a quote of an electronics engineer in the wiki page saying: "there is probably no music on the planet that has not passed through a hundred or more 5532s on its way to the consumer" So the point is how a music processed through hundred of 5532s can be improved because of only one another opamp at the very end of the chain?

[@novem6erain]

NE5532 and Sparco s 3602 sound clearer than others, which means that you can safely leave the stock ones and rejoice

[@BoltRM]

My 2 favs as well. #3 my fav, #1 is my 2nd fav

[@Panslapper]

To further add, my V3 with the opa2604 sounds almost identical to my Onkyo A-9010, I like it!

[@fosiaudio]

👏Absolutely fantastic!

[@jrdelat5]

What brand?

[@Panslapper]

@@jrdelat5 Burr Brown…but the V3 sounds cleaner over all.

[@wyup]

Very interesting! I also have the Onkyo and I think it's a great amp for the price. How do you think i'd sound with the SS3602 (or Dual SS2590 Pros with adapter) and 48V supply? And paired with the new Fosi P3 preamp, it might take things higher...

[@Panslapper]

@@wyupI think you would surpass the Onkyo with that setup, especially for upper bass and overall detail.

[@Panslapper]

I now have this little amp and have gone through a few op amps but first I have to say that it sounds just fine straight out of the box with the genuine TI NE5532 op amps. I use it with an 36v 6a Aiyima power supply and it drives my Monitor Audio Bronze 200 (88db sensitivity) floorstanders quite well. I’m in a 5m x 5m room and the amp drives enough power into the speakers to fill the room at sensible listening levels around 11.00 o’clock to 1.00 o’clock on the volume dial so there is plenty of power left as the dial goes to 5.00 o’clock from 7.00 o’clock. It gets really loud past 1.00 o’clock. I messed about with various op amps including Oracle 02, Muses 8920d, various 5532s and eventually settled on the Burr Brown opa2604 which has the best soundstage out of all them, very wide and well detailed with a nice overall balance and good dynamics. I will try the opa1622 when they arrive as they sound similar to the opa2604 in other amps I have tried whilst the opa1622 adding a little extra air in the upper frequencies. The 32v power supply will drive floorstanders but the 36v is a more balanced choice for the bigger speaker if you don’t want to max the voltage up to 48v. I would say with the opa2604, this little amp reminds me of the Rotel A11 Tribute in some regards like detail for example but the V3 does have a wider soundstage with the opa2604 whereas the A11 tends to be more central but accurate nonetheless. The V3 doesn’t quite have the fullness in the low end as the A11 but I also would not expect most class d amps to do so. It’s still very good none the less and does deliver a balanced low end frequency. I’m quite pleased with V3 overall and for it’s diminutive size and simplicity of this unit it delivers a pleasant listening experience, an excellent choice in the current global budget range small class d series of amps. I am not affiliated or sponsored by Fosi Audio and my opinion is based on my own experience with the model I purchased myself from Ali Express and had delivered to the UK. Oh before I go, I forgot to mention whilst driving the unit at around 1.00 o’clock constant, the V3 never grew hot, not even warm after 1 hour! Excellent thermal management!

[@fosiaudio]

We appreciate everything you do, we will keep up the good work!

[@Panslapper]

@@fosiaudio My pleasure.

[@JMJM75257]

You reckon the opa1656 would be a good drop in replacement? I've got the opa1612, opa 1656 and the opa 2604 on order. Unfortunately I'm thinking the 2604 will probably be fake. I got the ceramic aq version to try and reduce the chance but we shall see. I hadn't thought of the 1622, is it much different than the 1612?

[@Douglas_Blake_579]

The problem in other amps has never been the NE5532s ... it has been *fake* NE5532s. Some of the other amps and boards are coming out of the factory with rebranded chips in them... and they are causing all kinds of silly problems. But, of course replacing them cures the problem and falsely gives credit to what ever you stuffed in there.

[@Panslapper]

@@JMJM75257 …the 1656 might be fine. I have never heard one myself but its quite a well regarded op amp. The 1622 is ok too. My personal favourite is the opa2604, its the one i can listen to the longest and is well suited to class d as it negates the often leaner sound of class d amps. I have a few ceramic opa2604 from ebay seller in China and they are all legit. You should be ok with them, ceramic is not easy to fake and costly to do so.

[@m4nc1n1]

Great demo! Not easy to show the difference on KZbin, but you nailed the recordings. Just got the V3 direct from you. Ordered with the Orange knob and the 48V. for $115 all in with shipping and tax using a coupon. Great deal, thank you. I already have the Sparkos in my A07 (dethroned, btw), so I might put them in after I use it stock for a while. Sounds fantastic on my DALI SPEKTOR 1s. IMO, the Black knob should be optional and the Orange the default. Makes your V3 stand out among the rest. My one complaint is the binding posts. Please use ones that fit banana plugs in the V4.

[@danielmelendrez1616]

I just want to give you a quick heads-up. I confirmed that the LME49720 is also a great drop-in replacement. It opened the sound stage and gave me a tighter low-end. I was truly impressed! Another note for #fosi engineers. Please make sure that there are no flux residues on the pins of the TDA amp. I inspected mine under a microscope and while I was positively impressed by the cleanliness of the design and overall layout, I found too much resin residue on the legs of the main amp chip. This could potentially capacitively couple the signal and create some perceivable distorsions, I believe. I was able to carefully scrape it and give it a good wash with 99.9% IPA and the chip is clean as a whistle now. Just for the kicks and giggles I applied Arctic Silver 6 thermal compund and I believe that the thermal transfer had a slight improvement as I feel the case getting hotter faster (which if you think about is good ;) )

[@fosiaudio]

Thank you for everything you put into this. Yes, I have forwarded this to our engineer, thank you for your great professionalism, we will pay special attention on it.

[@JMJM75257]

​@@fosiaudiohi could you tell me what the rca Input impedance of the v3 amp is? Thanks.

[@rxt744]

To my old ears... definitely the SS3602 followed by the MUSES02 for an op-amp upgrade. The others are OK and decent... in decending order OPA2604, NE5532 and then the JRC4580D. Thanks for the comparison!

[@maroof8905]

Compare to Stock NE5532 the difference is not worth of 160$ for Sparkos.These tiny pairs of op amp seems expensive for me.

[@tomekichiyamamoto2177]

Thank you for this video. KZbin compression may lost a lot of details, however at least we can hear that there is difference. Even good or bad thought 😊 Thank you

[@aeon7748]

The purely musical sections was most enjoyable and overall cohesiveness was with Sparkos but also the Muses had incredible detail and micro dynamics you could hear the sound of fingers hitting strings of the guitar, OPA2604 had very recessed highs and small soundstage, I wish you test OPA1612 which is more preferred by most than 2604.

[@mmeail1492]

This amp is samply amazing stock from the box, Fosi should do a bridgeable version of this amp with a 48volts 10 Amp power supply

[@Douglas_Blake_579]

It already is bridged. The TPA3255 chip is running in Stereo BTL mode. (Bridge Tied Load)

[@aaronb1138]

@@Douglas_Blake_579 They're talking monoblock PBTL with double the power available, but more importantly, better output quality at moderate to higher volume (power) levels. The Fosi BT30D Pro already does this with 2x TPA3255 - one driving the two stereo channels, and another in PBTL mono mode for the sub channel (spec sheet L/R 165W, sub 300W, depending on PSU). I think more people are interested in Fosi next implementing PFFB. The only vendor which I am aware doing this is / was 3e audio selling DIY modules and a few others. That said, for monoblock-like TPA3255 implementations, a dual TPA3255 with PBTL + PFFB would be great for a straight stereo amp. Perhaps PFFB investments also call for Coilcraft flat wire inductors and a few other component upgrades. A single TPA3255 sub amp with adjustable lowpass and PBTL (as current models) but with the power handling and quality of the BT30D Pro or V3. Personally, I would also want an adjustable or jumper selectable highpass / rumble / subsonic filter, but that's mostly because I am playing with tapped horn subs which require a highpass at their frequency response knee, otherwise they blow drivers more easily than most. Some more generous power caps, probably 63v 105 deg rated like the V3 so it can easily handle 48V input, but maybe 2-4x the capacitance for a sub amp. As for this video, it really makes me happy the default op amps are the NE5532, as the only one I liked nearly as much was the OPA2604. The rest were softer and sometimes unnecessarily warm (more just bottom heavy, but like HT ported sub flabby). I like women's vocals breaking away from the band as well as hearing the bass player's fingers in the plucking (in this example) which more detailed presentations provide.

[@Khontaros168]

Fosi ZA3

[@oahupc4688]

I don't know what the point of listening to compressed audio on KZbin out my tiny quarter inch cell phone speaker so I can hear the differences in op amp quality is...? But I just installed the sparkos op amps in to my v3 and it sounds incredible, it's also going through my minidsp flex for even more refinement and clarity (I also recommend the schiit Lokius) it sounds mind blowing good that's all I can say! You will need two or three op amp risers on each one for it to fit otherwise the capacitors are in the way. But honestly the sound is amazing!

[@thomasstanfel7589]

If inside clearance wasn't an issue The Orange Dual Discrete Ops Amp is a great option..its my favorite besides Sparkos Labs ss3602. Great video.

[@johntan4835]

Hi i install sparkos on my v3 with 1 riser for each sparkos

[@thomasstanfel7589]

@@johntan4835 I bet it sounds good.

[@johntan4835]

@@thomasstanfel7589 curious about your orange dual discrete op amp also

[@SpirallingOut]

Use a scratch awl to mark out & a Dremel to cut out 2 clearance holes from the casing after the warranty runs out.

[@cmalc8]

Funny thing is, the original it comes with sounds best to me (the NE5532 is the one it comes with isn't it?)

[@jimmyzhang0598]

I have both bt20a pro and v3, replace the op amp on each with opa2604, turned out the bt20a pro with noticable background noise, the v3 is still silent, sound quality on the v3 with opa2604 is much much better than bt20a pro with opa 2604, the v3 with opa 2604 has more bass and treble than the stock op amp, overall more enjoyable than the stock amp, v3 with opa2064 is a good to go,anyway that 's my own opinion,hope that helps

[@poopandfartjokes]

Say opa2604 one more time! I dare ya! I double dare ya!

[@carlocarnevali7790]

Would you say the bt20a pro is an overall worse amplifier than the v3? Just bought it, may as well return it for the v3 while I'm still in time 😭

[@watdanuqta-mf5ms]

Hard for me to tell but I thought that the JRC4580D was louder than the NE5532, wasn't impressed with the discrete op-amp, but the OPA2604 seemed nicely detailed. But over the internet it's not that easy to make a definitive choice, not to mention the Sparkos are a lot more costly than the V3. Add to that the cost of the 48 volt p/s, might as well go for a nice integrated amp like a Cambridge?

[@Subde18]

*NE5532* saiu disparado na frente 🔈🔉🔊💯⭐⭐⭐⭐⭐

[@ramonrequilman2127]

For me it's Muse02 and OPA2604.

[@VirusForPrez]

Texas Instruments (opa2604) for me ! these opamps rock / clear dynamic and incredible 3d soundstage !

[@fosiaudio]

That's fantastic!

[@jericlee1509]

i agree... last one sound the best

[@christophedecavalla2941]

I think going with the NE5532 was the correct choice. Sounds the cleanest to my ears and spending twice what the V3 costs on op amps for it borderline on insanity.

[@MichaelBeeny]

@@christophedecavalla2941 The 5532/4 is probably the cheapest, so one costing 10 times the price has to be better, of course!! Placebo effect.

[@editorjuno]

Texas Instruments also makes the NE5532 -- and uses it in the their own TPA3255 evaluation board.

[@liubomir4o]

From the presented track difference is quite negligible and seams that the stock op-amps are good enough. Considering that some of the op-amps will double the price of the V3 improvement in the sound (if such at all) is not something which worth spending such amount of money . My opinion

[@horsterer77]

Thanks a lot for the comparison video! I just recieved my Fosi V3, and am quite impressed so far. What would be great, and something I couldn't find yet - basic instructions on how to change Op-Amps in this little amp, which ones fit and how, for people like me who never heard about changing Op-Amps before.

[@jonnynevada8915]

Hands down,, the 5532 ROCKS 👌

[@nishamnazar7005]

Im wondering where the low end freq is. The difference between a07 and fosi v3 what i find is in the extreme low ends. When i bought this one, i could t literally get anything less than 100hz in my ear. When swapped with the aiyima a07 it was a huge difference in that region. Im wondering what is happening while speaker loads are connected. It doesnt show on the scope

[@wegardfjeld3789]

I've used the new Fosi P3 from kickstarter project, wiim pro and Eversolo D-amp 6 master edition, with and without Geshelli J2 Akam to drive the V3. I suspect we have a bad or fake op amps in our V3. Mine has no response under 120hz. This follows what many have said about fake/bad op amps used in some products. My bt20pro tube sounds way better, goes down in the bottom end too, wich is a massive disappointment after the reviews V3 got. Fosi can give disclaimers about the different looking op amps, but fact is people swapping to "same" op amps from renowned producers experiences great sound improvement. I do have the 48v togheter with it. Also tested 36 V. Sound is awfully unpleasant light and veiled. No I'm not buying better op amps to potentially fix a bad inexpensive product.

[@D1N02]

Sparkos ftw, nice open an relaxed and subtle. Are the op amps for the right and left separately? Or are they in series?

[@fosiaudio]

They are in parallel, each channel has its own independent op amp.

[@vincentw9610]

I just bought my first amp and its a fosi ZA3 very nice amp btw. but I would like to get some more out of it.. whats about the BURSON AUDIO V7 VIVID PRO ?

[@lahirupathirage5972]

I've tried OPA and NE Ics. What worked for me is raw transistors.

[@stefanweilhartner4415]

sparkos it is 🙂

[@lahirupathirage5972]

​@stefanweilhartner4415 That seems legit. Will try that. For now, I love how classic BC550, 560 couple sounds. The highs are very brighter than op amps. I like TDA1308 too. That little Philips IC gives a flat sound without mud.

[@stefanweilhartner4415]

@@lahirupathirage5972 recently i saw some smd transistors at onsemi coming in pairs with even a higher amplification than bc550/60. a matched pair in a single package might be perfect for a discrete differential amplifier circuit. but i am not sure about their size. some are are too small and maybe too much of a challenge to solder.

[@RandomShart]

Surprised to find that the stock ne5532 sounds really good, smooth punchy bass and crystal clear forward vocals. It will always come down to personal preference but based on this demo I won't be in a hurry to spend money on op-amps, so I can instead invest the money somewhere else e.g. bump up the dac / phono stage / speaker budget instead.

[@kineahora8736]

I also thought the NE5532 was the best. I couldn’t really decide among #3, #4, and #5 which was better-they were all pretty good. But I really disliked #2 the JRC4580D which to me sounded constricted and muffled as if you were listening through a tunnel.

[@stevehiggins9227]

@fosiaudio I was wondering about the TI LM4562NA? And can you share the output impedance that is driving the opamp? I think one of the Douglas Self books said the sweet spot for the 5532 was about 1K. Wondering because the LM4562 has higher input current noise than the 5532.

[@wormdamage]

What performance parameters would you say accounts for these variances in this context? Not sure I'd ever even think to talk about the 5532, 4558, or 2604 in the same sentence generally. Just curious. Thanks!

[@MrDavidBFoster]

I actually listened to this on a V3, and the default NE5532 sounded the best to me. Maybe if I had one of the other op amps I would prefer that one?

[@RUMBLEGO1]

Usually I can easily discern differences even on KZbin clips. I am listening with a V3 and heard absolutely no difference with any of those opamp's. I actually have a pair of Muse02's but haven't installed them in anything yet. The V3 sounds excellent as is! Curiosity may get the better of me in a few months however and the Muse's may go in.

[@johntan4835]

Once i change my op amp with sparkos the oem op amps installed was literally destroyed

[@crazyprayingmantis5596]

You should be able to hear the difference it's pretty obvious

[@Douglas_Blake_579]

_" I am listening with a V3 and heard absolutely no difference with any of those opamps"_ And that should not surprise you at all.

[@RUMBLEGO1]

@@Douglas_Blake_579 It actually does surprise me. I have heard comparison vids on just three separate Muse opamps and i could easily discern the difference between all three of those. Actually makes me wonder about the legitimacy of this comparison frankly. I hear VERY minimal difference and have decent ears and a resolving system. Going quickly back and forth between the Sparkos and the stock NE5532 several times....there ain't nothing getting destroyed.... at least on this vid. Not to say that is not a real world experience but just not on this vid for me.

[@Douglas_Blake_579]

@@RUMBLEGO1 _" I have heard comparison vids on just three separate Muse opamps and i could easily discern the difference between all three of those."_ The truth is that the op-amps they're letting you change are running as unity gain phase splitters to drive the BTL outputs in the TPA3255. At unity gain any difference between op-amps is going to be so tiny I'm not even sure you could measure it reliably. Now in a circuit with some gain, like a mic mixer or phono preamp there can be differences and sometimes they do matter... but at unity gain... not so much. I'd bet your experience from the Fosi video is genuine and perhaps the video for the Muse chips was altered a little bit. Don't forget... Muses is trying to sell chips... Fosi isn't.

[@Robert.Chauval]

Why use the discontinued OPA2604, you cant buy these anymore? My rock solid preferential opamp for upgrading 70 and 80s hifi gear is the OPA134.. class A output, very low Vnoise and Inoise, unity gain stable. Its half the Vn and In of the OPA604. TI are now recommending the OPA1656 as replacement for both the 134 and 604 series. Its got similar slew rate, half the Vn of the 134 and 1/4 of the 604 while In is the same as 604.. with 53MHz GBW rolling it will give much higher ngfbk margin at 20kHz than any 5534 that will drop THD significantly and with the higher GBW the larger more linear phase margins should mean it has a good listening experience also.. When upgrading any opamp thats driving cable/interconnects i use the LM4562, designed to drive 600 Ohm loads at low THD and noise.. both these opamps 4562 and 134 are cheap available and very good. Im not a fan of opamp rolling without a thorough understanding of the feedback network it has to serve. I expect a lot of the audible difference rollers may be hearing is due to an ill considered fit and undesirable complex effects. Theres a lot more to opamp upgrades than buying the latest shiny thing and just whacking it in. "opamp electronics" needs to be well considered also and we havent even discussed 1980s opamp power supplies and how to deal with them yet either........

[@pjman01]

Does anybody know where in the block diagram the opamps go? Just before the input to the power amp? Tone controls? One each for bluetooth and RCA input?

[@ricsim78]

To anyone on ASR who thinks all OP AMPS sound the same, you can clearly hear differences even in this video! The NE5532 these come with are not exactly pristine quality, yet still sound overall best in this video. I even found swapping to genuine NE5532 from Digi-key made my Fosi Audio Tube preamp sound even better and punchier. The LME49720 I found to be better in the bass than the treble, the metal versions with an adapter would be even better. Just do not expect it to make your system sound way better by doing this, the speakers and amplification are the most important and must be up to snuff. You can improve the sound a bit, but you can also make it sound worse.

[@pyntzer]

Do you have the opportunity to compare de NE5532 with Muses02? Thank you.

[@ricsim78]

@@pyntzerMuses 02 is better sounding than the NE5532. It sounds less digital and richer, I hate using phrases but it sounds deeper and more analog. The NE5532 sounds okay, nothing wrong, nothing incredible.

[@pyntzer]

@@ricsim78 Did you install the Muses 02? After your answer, I installed again the Muses 02, I will try one more time. First impression is a bit sharp. Thank you.

[@ebkesq72]

They all sound the same to me.

[@ricsim78]

@@ebkesq72 You need your hearing checked then. Or have a terrible system with low resolution.

[@johnoakes7922]

I recently purchased a pair of sparkos opamps. When I first installed them, I was not impressed. Actually I couldn't hear a difference. As more and more time passed while listening to every track detail by detail. I noticed how every single facet of the audio I was hearing improved tremendously (Soundstage, depth, imaging, transparency etc.). At first I felt let down after coughing up $160 for a pair of the sparkos SS3602. I am more, and more impressed every day with the Sparkos. I am so happy with my purchase. Well worth the cost. I have an EQ that has 12 replaceable NE5532 Opamps. I am thinking of replacing them with Sparkos SS33602, and the Burson V5i Opamps. I do like the NE5532 Opamps a lot. I just like Discrete Dual Opamps a lot more. CHEERS!

[@lukaszdziaba8687]

Can I use Burson Audio Supreme Sound V6 Vivid Op Amp on this model? Great amp btw, I really like it !

[@cmalc8]

I wonder what it would sound like with a MUSES op-amp.

[@jedi-mic]

Interesting I prefer the ss3602 the more natural open sound and livelier more detailed. What are these amps liked run in monoblocks? Is there match or any improvement?

[@ayc3695]

you have good ear

[@richi5831]

I read the V3 comes with the TPA3255, where is that chipset in this sample? Why am I reading that it was designed with NE5532? Confused here..

[@fosiaudio]

TPA3255 is a power amplifier chip (AMP chip), and NE5532 is an operational amplifier (op amp) chip.

[@korling99]

Do I need a pair of the same opamps or can they be swapped in different combinations?

[@fosiaudio]

It is essential to use a pair of identical op-amps.

[@oahupc4688]

Fosi , so which in your opinion sounds the best for this amp?

[@clarencehoover6748]

Anyone who plans to remove an op amp from a socket should absolutely invest in a chip puller. It’s cheap and helps you safely remove the device without bending pins.

[@m4nc1n1]

If anybody wanst to know, the Blue Jeans Cable Ten White Speaker Cable fits the binding posts perfectly.

[@vincenthernandez3009]

I just ordered one on Amazon. Can you hook up a powered sub wooder to this amp/ Thank you.

[@arijitgayen644]

Are NE5532 and JRC5532 different sounding?

[@sloker874]

Does the Sparkos Op-Amps fit in without DIP Sockets? I don’t see much space there to fit them… thanks!

[@fosiaudio]

It is necessary to use DIP sockets or risers.

[@sloker874]

@@fosiaudiothanks! Looks like the amp already comes with risers??

[@oahupc4688]

You will need two or three risers each to get above the caps for sparkos

[@lelogis6872]

For me, the best is JRC4580d, concentrated and detailed musical, second is NE5532, airy and crispy, after muses02 and ss3602 opa2604 is worst position.

[@BigNorthumbrian]

I have two Aiyima A07s, I’ve been using one with OPA2604s for the last few months, which were a definite improvement over the NE5532s. I received a pair of Sparkos SS3602sa few days ago, so I’ve been comparing them by just swapping the amps over. Big difference, more open and airy treble, wider soundstage and blacker background, so getting more detail, bass is well defined. Expensive, but definitely worth it.

[@pastaman6099]

Which op amp would be the most efficient with low bass?

[@fosiaudio]

Sparkos SS3602

[@duboracle]

The NE5532 sounds best, but i ask myself if its normal ? Did the other opamps had the same burn-in time ? I think thats the case namely.

[@editorjuno]

Op-amps have "burn in time?" Seriously?

[@duboracle]

@@editorjuno New equipments always has to settle in for some weeks, but what could be a other reason that the NE5532 sounds better ? In other comparisons the differance whas way less then here.

[@hyperion7772]

Burning time doesn't exist for electronic components.

[@duboracle]

@@hyperion7772 You think, but there is no other way the results could be like this without this conclusion.

[@ferrarabacj]

Sorry, which does it come with it by default?

[@fosiaudio]

It comes with NE5532 Op-Amps by default.

[@ferrarabacj]

@@fosiaudio Thanks a lot! i wonder if this nice amp would be a good match for triangles Borea Br03. Is it a warm sounding?

[@AllHandlesHaveBeenTaken]

I have a pair of a07 MAXs. I ordered some moses02 and opa2604s from a trusted source. Still waiting for them. Even though opa2604 is not made anymore and hard to find genuine parts, there is a workaround. Opa604 is the single op-amp version of the opa2604 which is dual. Opa604 is still available and can be combined to create the equivalence of an opa2604. Brown Dog single to dual op-amp adapters can do just that. The opa604 is a SOIC package and Brown Dog has adapters with dual opa604s converted to DIP. I ordered a couple of those just to see how they fit. I have seen multiple people claim that the muses02 and opa2604 are the best match for the a07 MAX and I am going to find out.

[@donnywidodo8874]

any update would be appreciated

[@AnhNguyen-iw7cf]

Im playing two A07max in mono. Using LM4562NA very cheap opam but... Wow... Very detail and soundstage

[@machawley]

Which op-amp most closely matches the input signal? Discussing audio quality for each is actually a discussion of distortion. Let's lose the distortion as much as possible.

[@dixter1652]

would be cool to have a option to turn these intto Mono block amps so I could make a balanced pair for headphone amp...

[@matytinman]

Ranking: Sparkos SS3602, OPA2604 and... JRC4580D, NE5532 small differences MUSE02 the worst! Weird sound, where are the bass? Sparkos is too expensive, then OPA2604 is the best choice. To the future, maybe OPA2828 with DIP adapter NE5532 vs OPA2604 -> the second is more musical, better voice

[@matytinman]

Or OPA828 Dual OP

[@JMJM75257]

Has anyone tied the opa1656 with this amp yet? Looks comparable to the 2604 specs wise. I've got both on order although thinking the 2604 will probably be fake.

[@Ivan-ks1ix]

How are they? I’d like to order some but can’t find a reliable source and don’t want to pay Fosi’s prices.

[@JMJM75257]

@@Ivan-ks1ix Not as good as the 2604 imo soundstage seemed more closed in but it did in my view have slightly better detail at the cost of less soundstage and a softer bass presence.

[@ifyoudrivecar7849]

NE5532 simple the best!

[@MilesTeg_cy]

I get much more details with OPA2604. But that's just me. Different hardware and different pair of ears.

[@klepp19]

Please make a stereo amp or mno blocks so I can use my own pre amp!😊

[@fosiaudio]

😀We are developing mono block amp now.

[@Douglas_Blake_579]

You can connect your Preamp's main output directly into just about any amplifier. Use the amplifier's volume control to set your maximum listening level, then use the pre-amps switching and controls to run your system. The V3 is not a good candidate for this since the power switch is on the volume control.

[@4.20.69]

@@fosiaudio this is quite exciting news!

[@fosiaudio]

@@4.20.69 I know!

[@Jil8840]

THIS Amp has the TPA3255 chip, correct??? Why you didn't add it's original chip in this test to hear how it compares to the others and decide if its worth changing.....????

[@fosiaudio]

Yes, the V3 amplifier features the TPA3255 amplifier chip, and it originally comes with the NE5532 OP-AMP chip. In this video, you can observe the different performance and characteristics when using various OP-AMP chips such as NE5532, JRC4580D, Sparkos SS3602, MUSES02, and OPA2604.

[@Jil8840]

@@fosiaudio so the first in the test is actually the one thats inside originally, right?? It sounds the best.

[@editorjuno]

@@Jil8840 -- It's also the op-amp TI uses for its evaluation boards, even though they also make the OPA2604.

[@m4nc1n1]

Yes@@Jil8840

[@aitchr8770]

The op-amp is not the main amp chip.

[@carlocarnevali7790]

What about the LM5264?

[@eatdrinkwineguy]

Be great to have the files for download to hear properly.

[@danueyang7191]

sparkos ss6602 makes me feel narrow in reverbration

[@RemontKvartir39]

ne5532 стоит всего 2$ , о каком качестве звука идет речь? это сток..

[@HappyHighwayman]

They sound identical

[@Grumpy6]

NE5532 best,very neutral and balanced.JRC4580D the worst.Depends on the speakers amp and speakers too,which you not mention them.

[@johntan4835]

Why are no links on where to buy the other op amps , also will fosi be releasing v3 series with mono mono capabilities like sabaj in the near future???

[@fosiaudio]

You could order other op amps on our official website, we will try to release v3 with mono features. fosiaudioshop.com/products/op-amp-chip-muses02-opa2604ap-opa2134pa

[@Douglas_Blake_579]

Also try simply searching for them ... most of the online vendors carry at least some of them.

[@brunobassi2440]

The 5532 world is vast from shit to high quality. . I prefer nxp 5532a/bpa but not easily available. Muses02 is probably the best for classical music because it allows you to appreciate even the most hidden musical instruments behind .... but not suitable for Sunday audiophiles.

[@worldspacechina]

you boosted the bass of the BGM trying to impress the audience but that's a big fail.

[@lllllllllllllllllllll1lll1]

I noticed the same. NE5532 sounds much better than the others for that very reason. Op-amp rolling, at this caliber of op-amp, would have an extremely negligible effect regardless. NE5532 is more than enough for this application.

[@isometrus]

Well, we need more opamps included

[@Paxmax]

For me the Muse and JRC are no-go's. I think the Texas held up it's own very good, especially in clarity/legibility, tho at a price of warmth. I'd be hard pressed to motivate myself spending any serious bucks swapping the op-amps. Maybe OPA would be interesting to try out. Maybe I might get a "aah heck no" response finding out what the cost would be.

[@birdyflying4240]

i use opa2604 and love it, not expsensive as well.

[@Paxmax]

@@birdyflying4240 Alright! Thx for the heads up!

[@ricsim78]

To be honest, I tried a few different OP AMPS in my Fosi Audio preamp with GE Jan tubes. Swapping the stock OP AMPS from the generic (likely imitation) NE5532 to genuine Texas Instruments NE5532 from Digi-Key actually gave by far the best sound. I also tried the LME49720, sounded better in the bass side than treble. The OPA2132 sounded pretty good, but I most preferred the genuine NE5532. That makes sense, because those are the OP AMPS most of them are designed with (Fosi, Douk, most of the Chi-Fi amps). Swapping the tubes from the stock to the GE Jan gave the most impact to the sound.

[@birdyflying4240]

@@ricsim78 I did the same tube swap to GE but went back to standard tubes after some weeks listening. The GE's gave a less focussed sound, more wooly warm, but lacked clear imaging. Use them with the OPA2134PA and the OPA2604 in the Aiyima a07. Sound great, the tubes warm up but still with punch and dynamics. It comes close to a class A tube amp i owned.

[@Panslapper]

@@ricsim78 Mullard EF95 are nice too.

[@lextr3110]

try TL072 and opa604

[@philipkershaw7918]

Lot of snake oil thinking and confirmation bias going on here fella's. The fact is that the Fosi V3 is a great sounding class D amp whatever pair of op amps happen to be in circuit. To meaningfully conclude otherwise would require proper, double blind, listening tests. Whereupon, and as is often the case, all these notions of difference would, no doubt, be shown to be... well, lets just say unreliable. I bought my Fosi V3 out of curiosity to see how the TPA3255 chip in the Fosi compared to the TPA3251 chip in my AIYIMA A04. And to my ears, and the ears of a couple of trusted friends the differences [if any] are small indeed. And that's across different chips in different implementations! I suggest we steer well clear of the falibility of opinion and embrace instead proper scientific methodology and the law of diminishing returns.

[@aitchr8770]

"proper scientific methodology" which is?

[@philipkershaw7918]

Reading beyond the first two lines of my comment you will notice that I suggested 'double blind listening tests'. This would be a good start, would it not? But given the...shortcomings of our ears, well, the oscilloscope is our friend.

[@mikepxg6406]

Every mixing desk in the audio chain has gone through hundreds of NE5532. So you put in an unsuitable OPamp in a little box in your living room, you hear some high frequency noise and think it sounds better because you paid more for it, Unless you can test an improvement you are probably making things worse.

[@Scrufboy]

There is more bad with the pass-through. Please test this yourself if you can. First... The pass-through works both ways... You can input via the 3.5mm too. Then you would use the RCA as outputs. Just like the Aiyima A07. It is really only a Y cable. Not even a line out. So here is the nail in the V3 coffin. I found out last night that the RCA and 3.5mm pass-through of the V3 are wired wrong and when another device is plugged into the V3, while conducting an isolated L-R stereo separation test, reveals the crossed signals. This error doesn't happen when you only use the RCA(or 3.5mm) input alone... But as soon as you plug something into the V3 for output... L-R tests reveal the cross-fed signals. When testing, the left channel will play and a reduced signal will play in the right channel too and vice versa. This should not happen. Fosi Audio obviously copied the original circuit layout of the Aiyima A07. The A07 also had this error in their first run... They did fix it... So they say... For Shame Fosi! You will have to split your signal before your V3 and feed your secondary device that way. You cannot use the pass-through in the V3. The entire first run of this device is junk for anyone needing that pass-through to work as intended. Buyer Beware!

[@editorjuno]

The first runs of the super-popular Aiyima A07 had the same issue. It's clearly an inexcusable flaw, but hardly a coffin nail for the vast majority of users who will never bother with the 3.5mm jack.

[@Scrufboy]

@@editorjuno They still have the issue. So does the recently released A07 Max. Not A07 Pro.

[@editorjuno]

@@Scrufboy -- Not an issue here, and easily corrected with a simple cable solution. I declare a trivial case of mountain-molehill syndrome, YMMV. 😎

[@Scrufboy]

@@editorjuno Actually - this cannot be solved with a simple cable solution. Actually requires a revision. I've been working with Fosi for he past month. Revisions for both he V3 and the M-03 are coming.

[@Scrufboy]

@@editorjuno Well, to be fair... The solution does lie elsewhere. But, it is best had now with a Tilear 1 to 4 lossless RCA Splitter. Personally, This device can and needs to be made better, quieter as it has potential. - Currently their opamp implementation means no back channel feeding. So it works. Simple cable solutions, not so much. Others are correct to state though, that for using these types of amplifier units with their simple pass through, alone. In a stereo rig, This might not pose an issue. Some though have also said they hear this effect at louder volumes even without the attachment to any amplifier. Certainly not when you attempt to stack the V3 upon itself. That is to say, any units designed today that have this simple RCA to 3.5mm passthrough that is labeled as AUX, pre/line out... When it isn't anything but a Y cable. It is this nature of that connection that makes pairing this with a dedicated sub amp difficult. That is after all, what the output is for. It only happens because of the summing of the channels on these subwoofer amps

[@joicejewerly5579]

Only change is the photos😂😂😂

[@cwbh10]

definitely the weirdest video ive seen featuring different op-amps.. performance is really going to be dictated by the surrounding components to the op-amp

[@g.fortin3228]

Sounds nice in vocals and treble but the whole thing, all of them, seems muddier at the bottom end than I prefer. It may just be the song choice.. I'd like to hear something different , this video 2.0 it's probably the music.

[@ebkesq72]

They all sound exactly the same to me.

[@jgbelmont]

Play the same section of each song genius!

[@Douglas_Blake_579]

Okay ... I get that Fosi is trying to break into the audiophile market... but this just isn't the way to do it. Climbing in the Oil pit with the Snakes is not going to win you any big praise or prize from audiophiles who still measure the quality of their equipment in Dollars Per Ton and argue over the best RCA cords.

[@davestevens4193]

Discrete design=better sound

[@editorjuno]

Audiophool nonsense. A huge percentage of our most widely admired recordings were created with studio mixing consoles that depend on *dozens* of ordinary, off-the-shelf NE5532s! An op-amp based on discrete components cannot even approach the extreme precision that can be achieved on a silicon die!

[@davestevens4193]

@@editorjuno ahhh...no opamps

[@editorjuno]

@@davestevens4193 -- With all due respect, WTF does that mean? If professional studio equipment manufacturers continue to use NE5532s by the dozen, exactly how does "ahhh...no opamps" support your original contention of "Discrete design=better sound?"

[@davestevens4193]

@@editorjunolook at any end game headphone amp. No opamps. Keep it civil.

[@editorjuno]

@@davestevens4193 -- "No opamps" is a marketing-driven "feature" that has no repeatable correlation with measurable audio quality.

[@ColocasiaCorm]

all sound bad. this comparison sucks.

[@fabioVTM]

Diferença nenhuma!! Coisa de bobo ficar trocando isso!!

[@fontanamarcos]

Vixe. Se não percebeu a diferença, seu ouvido tá zoado. Jesus.

[@fabioVTM]

@@fontanamarcos você é médico? Seu bobão!

[@fabioVTM]

Quase ia comprando isso amp operacional, pra trocar no meu aparelho, depois de pesquisar a fundo na internet, achei um vídeo de um cara especialista em amplificadores valvulado, e comprou um amp operacional dos EUA no valor de 80 dólares! E comparou com ne5532, ele falou que já sabia que esse componente não relevante pra melhora do som! Mais mesmo assim ele comprou pra mostrar o laudo e teste!

[@pyntzer]

@@fabioVTM tem o link disso?

[@alberto3028]

Deaf people expressing their opinions...

[@frankgeeraerts6243]

Opamps are ok even in high end and as tofday's universal complex digital/ processed circuits ...but they have no place or should NEVER be used in a quality musical reproduction system.........

[@Douglas_Blake_579]

Really.... you need to take a look inside some of your high end stuff... I'm betting there's plenty of op-amps there. No transistor circuit can match the gain, accuracy and low distortion of an op-amp.

[@frankgeeraerts6243]

@@Douglas_Blake_579 hahaha you're right i I don't use high end stuff but only components that play music ...worked long time for high end store but now I enjoy music and only vacuum state ( most build myself ) ....go and have a conversation with stupid people like P. Quortrup , D. D'agostino or J;Hiraga ...to learn about music reproduction or arethey fools also ?

[@MichaelBeeny]

Have you ever used or looked inside a professional mixing desk? It's full of 5532/4. No discrete preamp or amplifier can get the very close tolerances required to lower the THD and noise low enough, and cost pennies. I guess for high end stuff it simply has to cost a fortune. Does not sound any better but looks like it does.

[@Douglas_Blake_579]

@@MichaelBeeny It always kills me how these guys ditch on tone controls saying how they want to minimize the stuff in the audio chain, then go all gaga over discrete op-amps and high transistor counts.... go figure.

[@MichaelBeeny]

@@Douglas_Blake_579 You know when you are "flogging a dead horse" when someone comments "I had to raise my speaker leads a little more, as the sound was a little congested" It was time to block his channel, and have a cuppa T.