Why you need a mono amp in your system - Fosi Audio ZA3 review

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Could you please assist me
If I buy two ZA3 and use them as mono blocks. Is it a simple flick of a switch to mono and XLR ?? without changing any ops
2. Which would you prefer as mono blocks
ZA3
Or V3
Thanks in advance ๐๐๐
@AudioMasterclass replies to @grandmasterjo1: It would be better to consult Fosi directly for technical information as there may have been updates since my review. Regarding monoblocs, Fosi sent me two V3s and I am using them in in one of my systems with no problems.
@grandmasterjo1 replies to @grandmasterjo1: Thank you for your response and reply. Truly appreciate. ๐๐
Will revert to Fosi
Thanks
@EtaiAflalo-yc2qg: A comment for comments sake
@FBAV: Isn't a stereo amplifier just two mono amplifiers put together? And on the good old quality equipment you can switch them to mono. No need for these fancy things. Just ger hold of a good quality older amplifier that can switch to mono.
@FBAV: If you are an av producer you need to be able to check if it also plays back well in mono, in case accidentally some source is OUT OF PHASE. Also if a record is mono, you don't want an amplifier to be on stereo, because it will add a lot of extra noise and distortion.
@nickacht3301: When I'm drunk, I'll put something around ...๐๐ Why should I do that? ๐ค
@gpunique: I'm learning about balanced inputs. You mention this with XLR inputs. I wont be using those but will connect my DAC to the RCA input. IS that balanced as well? when an amp is "balanced" does that really only mean it has xrl ports? Can balanced also refer to headphone out (i know this doesn't have that but some DACs say they are balanced)? thanks for my noob question.
@AudioMasterclass replies to @gpunique: The RCA is not balanced as there must be three electrical connections. The RCA only has two. The purpose of balancing here is to reduce interference. Headphone outputs can be balanced. The purpose is so they can be 6 dB louder.
@cunawarit: My view is that, since I don't have an audiophile ear, I probably wouldn't notice the difference either way. Modern amplifiers are so advanced that issues like cross-talk are negligible. So, why spend twice as much to prevent something I can't perceive? I fully understand the benefits, but they simply won't apply to me.
@topobrundle2254: I see people who think that to listen to music you have to spend thousands of dollars on audio equipment and then you will have a pass to the world of audiophiles.๐๐
@frankd.b.9233: stereo is 2 x mono what now
@philthompson8574: Im still non the wiser buy a cheap amp or an expensive one? and if the latter what do you get that the Fosi doesnt offer?
@claptrap22: Took delivery of two of these today for my desk top system driving a pair of KEF Q350's. I'll say this - these amps have no business being as good as they are for the asking price.
@brianparenteau5310: No masterclass level knowledge whatsoever was offered in this video. Way too basic.
@AudioMasterclass replies to @brianparenteau5310: Let us all have a more basic and insightful comment then. Come on, dare you?
@marceloarenas5486: Thanks for this!!!!
@chinmeysway: ah so youโre a partially recovered audioperve
@chinmeysway: i like it other than that damn orange knob color!
@theman-pc2ej: Got one of these yesterday and it's great . Volume all the way up and speakers are silent!.. cranked it up and it sounds amazing.. definitely a keeper for my home studio!
@FBAV replies to @theman-pc2ej: That means your source signals Left vs. Right are out of phase
@theman-pc2ej replies to @theman-pc2ej: @FBAVย nothing is out of phase it's just a good quiet amp. 3k laptop, 1k interface and 1.4k studio speakers.. the amp couldn't get no better. My crown and my qsc both have a touch of white noise but this one is silent..
@FBAV replies to @theman-pc2ej: @theman-pc2ejย you don't understand what I mean. Question was why you need a mono amp? Normally you don't... I just gave two cases in which it might be useful
@theman-pc2ej replies to @theman-pc2ej: @FBAVย ahhh I see.. thats my bad man.. yea or in the case of running 2 of them to get more wattage.my speakers are vienna accoustics at 160w so this is a perfect match..
@philipw7058: If you put any electronics next to a speaker driver will introduce vibration into the circuitry which will find its way out the speaker,so learn about audio before giving information to people about proper placement
@AudioMasterclass replies to @philipw7058: Oh sh*t. That's it for active speakers then.
@philipw7058 replies to @philipw7058: @@AudioMasterclassexactly,high end is not active speakers ๐
@beprotishen: weak amp
@sabrowenie: Best unboxing ever!
@AudioMasterclass replies to @sabrowenie: Until my next one.
@fredashay: Wait! Why would banana plugs be illegal?
@AudioMasterclass replies to @fredashay: They are not, but there is legislation around them in Europe. Reason? You can plug them into a mains socket. Don't try it.
@fredashay replies to @fredashay: @@AudioMasterclass Oh! Thanks for the quick reply! I'm in America, and despite everyone complaining about our horrible outlet design, it's very difficult to plug anything into our narrow slits.
@fredashay: Actually, I have a retro hi-fi system with two mono amps (they're actually bridged stereo amps).
@ashneel: For the price.. it's a lil gem
@sepg5084: Where are the frequency response quantitative measurements tho? You already have a workable setup with that signal generator and oscilloscope, but only tested two frequencies somehow. 30 measurements from 20hz to 20khz and a spreadsheet graph could greatly help your content.
What sounds good to one person might not sound good to another.
@AudioMasterclass replies to @sepg5084: No thank you.
@DiscipleRay: What do you think about this amp running main stereo LR channels from the pre-outs of a 7+ channel AVR? Would it help much in taking the power demands off the AVR? Would running two as mono blocks improve things even more?
@larrygaines7462: I drive 8 ohm 3 way 70hz up and use monoblocks @ 48vdc , if you want more purfi ,hipex etc. My subs are duodayton18s. I am designer(50 yrs)
@wric01: It rocks 90% vs my latest and greatest gan amp. It's a multi do all play amp, once you tinker opamps mono xlr, then duo with mono or biamping without needing thousands to entry. It powers my magnepan lrs+ via single amp It's a winner. Duo Mono immediately adds realism faster impactful more fullness to everything.
@graememorrison333: Shhh. Put myself on the waiting list for two ZA3s, and then had second thoughts so cancelled. Suggested to Fosi though that if they brought out dedicated power monoblocs with XLR inputs then I'd buy a pair. Fosi quickly and kindly replied they're releasing that exact thing in a couple of months.
@AudioMasterclass replies to @graememorrison333: Yes it does seem that Fosi listens to their customers.
@MichaelManningPA: I know these little amps are all the rage right now. I have read a lot of these reviews, and I keep saying to myself, "why not just get a Crown XLi1500 Two-channel, Power Amplifier?" It's bridgeable, not "chifi," THD is <0.5%, 20 Hz - 20 kHz; it's 300 w @ 8 ohms, 450-Watt at 4โฆ. The Crown amp is time tested and a real workhorse and cost around $419 with a six-year warranty. This just seems to make more sense in the long run. What am I missing? Realistically, two ZA3's in Monoblock won't outperform one Crown. In that instance, for about $120.00 more, the amp outputs 900 watts bridged. $419 too much? Alternatively, get a XLi 800 for $339.00 and call it a day.
@msdprojekt replies to @MichaelManningPA: Donโt crown amps have fans? Bit noisy at low listening levels. There are of course plenty of other class D amps that could be classed as endgame and will last you a lifetime.
@memcdm replies to @MichaelManningPA: I have a Crown driving LRSs and a pair of Philharmonic Sound BMR Monitors via email eternal switch. Shocked by the great Sound even when compared to my Class A-B 40 pound dual mono.amp recently totally rebuilt. The Crown Sound very clean, clean and detailed. The 2nd level output indicator lights don't light up at eve. 95+ SPL on the Monitors. Drives the LRSs easily to levels too loud for my ears as well. Paid $499 when purchased and now $600. With a bit less power you could pay even less. ๐
@petertys: Do you have an issues when you slow down the volume the left channel is unbalance audio compare with right. Please comment..thanks
@Astrodicted: Dear personification of the cynical Masterclass teacher. I recently bought a 300ohm headphone, my pc mobo does not oompff it very well. Would you be so kind to consider a vid about decent desktop solutions?(kinda lacks on youtube imo) Btw, not willing to sell my kidney.
@AudioMasterclass replies to @Astrodicted: This is a good question. A high-impedance headphone needs more voltage to drive it so that is almost certainly where the problem lies. At present I don't have any high-impedance headphones but when I do I'll make a video on the topic.
@VicariousAdventurer: Most reviewers screwed up the basics of power measurement. Refreshing to see someone actually correct. UK versus US education?
@AudioMasterclass replies to @VicariousAdventurer: As I've only had UK education I can't comment on that. I'll stand by my preference for continuous average power measurements though. They many not reflect the listening experience perfectly but you know where you stand.
@VicariousAdventurer replies to @VicariousAdventurer: Also, everybody mods the input opamps, but I've only seen one guy for not cheaping out on the output. Having looked at TI's app notes, I have a hard time believing that any audible change (as opposed to changing a THD digit) will occur with improved input opamps; however, inductance drops as a core heats on the output is a real thing and might explain another reviewers results (and give me just that bit of buyer remorse for getting an Aiyima over a Fosi)
@VicariousAdventurer replies to @VicariousAdventurer: One guy praise Fosi for not cheaping out on the output stage
@VicariousAdventurer replies to @VicariousAdventurer: RMS makes sense - audio signals are >20 Hz. I was not going to post more stuff, but as I looked at LC output stage design notes and DIY audio forums and NAD/Purify bragging, I realized that the output frequency curve at high frequencies is only flat for a particular impedance. If the impedance is higher or lower than the design of the LC output is for, the frequency response will vary. NAD claims they've fixed this with a feedback network. but Fosi and Aiyima don't have the time/money for that, so you should have easily driven 8 Ohm speakers for the best results.
@soongpark683: Fosi aiyima bad sound
@ke5ufg: In mono does the sub out output in mono also?
@mattfranklin3622 replies to @ke5ufg: The Sub out is always mono, hence one output. ๐
@ke5ufg replies to @ke5ufg: @mattfranklin3622ย Sorry for my confusion: If running one Amp in stereo mode, does the sub out combine base from both left and right channels into 1 out for the sub? If so, running amps in mono block, you'd only get base from whatever channel is feeding the Amp. You'd lose base intended for the other channel? Or is base not recorded in stereo?
@ke5ufg replies to @ke5ufg: @@mattfranklin3622 I appreciate that and I don't want to be a hassle. Is base recorded in stereo? is different base information being sent from the source to the left channel than the right? If so, I assumed a stereo amp would combine left and right channels into one mono out for the sub. Is this all wrong? is the base information identical on the right as the left channel coming from the source to the amp?
Thanks
@mattfranklin3622 replies to @ke5ufg: @@ke5ufg Yes, the left and right audio signals, including bass, coming from the source to amp are completely separate. The sub out however is mono. I canโt be 100% certain but logically speaking the mono signal comes from both channels combined. Why do you ask?
@ke5ufg replies to @ke5ufg: @@mattfranklin3622 Thanks. I have two running mono block. With my limited understanding, I am concerned that if I use the sub out from say the left side amp that is only receiving the left channel, I may be missing base detail from the right channel that would have, on a stereo amp, been combined for the mono sub out.
@JustABowlOfCherries: I find mono to be better than stereo.
@jameswarren1831: The Quant Asylum Q304 is $600 and does a great job testing audio gear and by the look of your T-shirt I think you can afford it.
@AudioMasterclass replies to @jameswarren1831: Don't worry! eBay has kindly provided me with a Ferrograph RTS2. It will be making its debut soon. Oh yes, and a new batch of t-shirts.
@jameswarren1831 replies to @jameswarren1831: No excuses! You have to sell your soul to the audio gods! Iโm tall so my t-shirts are 3x the price and itโs limiting my ability to buy nice gear.
@m4nc1n1: This is the nicest-looking amp they have made yet. And the mono switch on the front is the dumbest decision they made yet!
@MarkThomas-hm3ju: This is probably wrong but just in case it's right I read where there are two TI 3225 chips one for each channel If that is the case what is the point of using the ZA3s as mono blocks. I know two power sources are often advantageous, one for each mono block but the Class D is very efficient. There probably is only one TI chip surely for each ZA3.
@chinmeysway replies to @MarkThomas-hm3ju: audioperves are just never satisfied
@billsmith5166: Getting complicated here, but since Fosi seems to be listening, how about an HDMI in and out along with an internal equalizer so that we could adjust via a TV interface Now that you've agreed to that, how about a mic input so that we can balance the room via a contained frequency response display also shown on the TV, or.. even an app. Now that you've also agreed to that, how about creating a DSP contained in the chassis with your wonderful amps? It would be just the thing to eliminate crossovers in DIY speaker design. There, that completes my list for now.
@billsmith5166: So if I provide 48V at 10A would I pretty much avoid the need?
@bobk3840: I donโt know why everyone raves about the Fosi amp. In mono is does NOT bridge the channels to increase output. It just uses one of the two channels. So buying two gives you the same output as one amp in stereo. I guess you get the privilege of spending twice the amount of money.
@Douglas_Blake_579 replies to @bobk3840: That is not how it works. In "mono" mode they are using a special high current mode of the TPA3255. In PBTL mode the chip parallels the two stereo BTL channels doubling the current capacity for low impedance loads... making it stable for 2 ohm loads.
You are correct there is no power advantage at 8 or 4 ohms... but if you have hard to drive speakers with impedance dips below 4 ohms the PBTL mode could be very helpful.
@jimbanville: So has anyone actually tested this ampโs ability to deliver more current to 4 ohms when in mono mode? All the tests I see, show a very minimal increase in watts in 4 ohms in mono mode vs 8 ohms.
@Douglas_Blake_579 replies to @jimbanville: That's right ... the mono mode is not like in AB amplifiers where bridging ups the power... it is a PARALLEL mono mode designed to give increased current capacity for speakers below 4 ohms impedance.
@jimbanville replies to @jimbanville: @@Douglas_Blake_579 Great. I need more than a datasheet for a chipโs capabilities. I need an independent test to show this fosi amp has substantially increased current capacity into 4 ohm loads in mono mode.
@Douglas_Blake_579 replies to @jimbanville: @@jimbanville
No sir ... what you need is a lesson in Ohm's law.
The data sheet tells the whole story. It's not an advertising document. It is an engineering paper that describes the capabilities of the chip to other engineers so they can use it properly.
@jimbanville replies to @jimbanville: @@Douglas_Blake_579
No sir. I understand ohms law. You are ASSuming this particular board and its power supplies are designed and equipped with all the necessary components to use this CHIP to its fullest capabilities. So you actually think no one should even have to measure the output to verify a board (and itโs PS), no matter how cheaply built, is fully capable of delivering the chipโs power specs. Gotcha๐๐ผ
@Douglas_Blake_579 replies to @jimbanville: @@jimbanville
Oh my, now you're starting to sound like one of those "conversation is competition" trolls.
I get it... you want proof.
Unfortunately you appear to be expecting the ZA3 and it's cousins to behave like Class AB amplifiers where "mono mode" actually means Bridged Stereo. The TPA3255 amplifiers we're seeing on the market are already bridged in stereo mode. That's what BTL -- Bridge Tied Load -- is all about. You can't bridge an already bridged amplifier... the chip is already producing maximum wattage at 8 and 4 ohms. What you can do is parallel the power outputs in PBTL mode for more current delivery, leaving you with a mono output that can handle very low load impedances. Your mistake here is in expecting an already bridged amplifier to act like the old school bridged stereo amps, and I can tell you from a couple of years experience with this chip... that simply is not how this works. In BTL or PBTL modes the output power will remain the same for 8 and 4 ohm loads... but in PBTL it will deliver surprising power at 3 and 2 ohm loads.
Things have changed ... try to keep up.
@adivarso8175: Fosi markets this as PBTL on the spec sheet. Not a true mono then?
@Douglas_Blake_579 replies to @adivarso8175: Yes it's true mono. PBTL is the TPA3255's mono mode,
@stevenewtube: Please do the impedance verses frequency video ๐
@IAmThankfulToday: I quickly realized that I had no interest in the product but stayed for the sarcasm...reminds me of a more verbose version of Granny Crowley, The Dowager Countess on Downtown Abbey. The script was quite funny and so promising that I subbed. Will be more than worth it when he gets his timing down
@allanmoorhead9492: It's surprising how small an audio power amp can actually be, if you take out the PSU and the radio and phono sections, and the input selection switches. Car audio amplifiers can be very small yet put out a very high level, far more than is needed for the small interior of a car for comfortable listening levels. It seems that many home audio power amps are made larger just to look more powerful.
@Douglas_Blake_579 replies to @allanmoorhead9492: These little guys are "chip amps" based around an amplifier IC chip. They are basically a chip in a box... don't need to be big.
@dost328 replies to @allanmoorhead9492: I thought I heard you said "McIntosh"๐
@VintageGearMan replies to @allanmoorhead9492: @@dost328 HA!
@PhilipBallGarry: XLR inputs can be especially useful with an amplifier powered by a switched mode power supply. If you've ever run your hand gently over the case of a device powered by a SMPSU you feel a tingle. That's because they're not fully isolated from the mains supply. It's not harmful of course, it's only a few milliamps but it does represent potential for noise to be imposed on any signal with a common ground. The three terminals of a balanced connector allow true isolation from the chassis of the equipment.
@Douglas_Blake_579 replies to @PhilipBallGarry: Horsepucky. There are regulatory bodies all over the world that would not let a product that posed a shock hazard onto the market.
@RomiPetrut: Thank you very much.
@AudioMasterclass replies to @RomiPetrut: You're welcome.
@RomiPetrut: Hi, it's a very good review.
I have a question: if I use two za3 as monoblocks with a tube preamp is it a good idea?
...and how is recommended to set the volume controls, at max on za3 using as main volume the preamp?
My respect
@AudioMasterclass replies to @RomiPetrut: Set the preamp volume to minimum then set the power amp volumes to max. Play some audio and advance the preamp volume slowly. It's almost certain this will be OK and you can continue to use your system like this, controlling volume with the preamp. Caution is always good though.
@Douglas_Blake_579 replies to @RomiPetrut: David is correct. But there is a plan B that works too...
Start with the pre-amp at 3 o'clock volume and the amps at 0. Advance the amplifiers until you get the maximum level you are likely ever to use. (for me this ends up around 11 o'clock on the dial). From there use the pre-amp to adjust from zero to your limited maximum.
This has the advantage that the kids won't be able to get you in trouble with the noise police.
@clemmtec9506: Dose the amp sound better than crown xls1502 ?
@Douglas_Blake_579 replies to @clemmtec9506: Less hiss ... but aside from that, when level matched, it's about a tie.
@JukeboxAlley replies to @clemmtec9506: โ@@Douglas_Blake_579no kidding? I had the 1502 and it's very good, so a set of these on a good preamp can most likely hang with the 1502 you think?
@Douglas_Blake_579 replies to @clemmtec9506: @@JukeboxAlley
The Crown is more powerful ... but at reasonable listening levels, yes I do think the Fosi will compare favourably.
@Off2Witness: Started my addiction with a pair of AR 3a, powered by a pair of MAC 60's. Yummy
@stu-po: These sold out really quick! I'm blaming your very informative review ๐
@fosiaudio replies to @stu-po: They are on pre-order on our website.
@immanuelsuresh7739: Will this be better or equivalent to Marantz PM 6007? In terms of power and sound quality.?
@wadesouza6402 replies to @immanuelsuresh7739: At the risk of being attacked by the Class D lovers, I would go with the Class AB Marantz for the combined package of including a solid more built out preamp with tone controls, good solid power supply with headroom and proven longevity, remote, quality components plus the 3 year warranty. I have 2 of the larger PM series amps, the 8005 and 8006 and they are excellent integrated amps which delivers more power and current than rated. They are obviously larger and thus take more space but they are also more adjustable in tone which many audiophiles hate but can help with crappy early recordings on CD, poor live recordings, etc. The comparison is kind of apples vs oranges. I have used these little chip amps in a garage with cheap speakers as well as on a deck where its all background lower quality listening. To me that is kind of their reason to exist. I have not found listening to them side by side that Class D is to me as transparent and good quality sounding as the AB amp. The Marantz is a good entry level amp which will likely service you much longer than this Fosi. If all you want to do is turn it on and listen to music go with the Marantz.
@immanuelsuresh7739 replies to @immanuelsuresh7739: @@wadesouza6402 somone selling used MZ PM7003 is it worth considering? Will be a better choice than PM6007? My speakers are q3050i.
@ChiefExecutiveOrbiter: Pual McCartney's ears are WORNG!!!
@davelistenstohifi: Thanks for the review. How does it sound though?
@AudioMasterclass replies to @davelistenstohifi: Not bad.
@jimhines5145: Listen to the best Toy Matinee release you can find through this amp. It's a true test!
@JayBeezy31: Would you PLEASE test the SMSL AO200 mark 2 ??? Uses the German infeneon chip and supposed to be โbetter โ than the amazing Texas 3255 chip, and the integrated amp Ao200 mk2 is only 200$ US dollars right now. I have the aiyima a08 pro itโs amazing for 92$ used , but I am eyeing the fosi zv3 or smsl ao200 mk2. I have Sony cs5 speakers 6 ohm
@Roddy451: 2:35 ๐คฃ๐คฃ๐คฃ๐คฃ๐ฟ๐ฟ๐๐ 14:37 ๐คฌ๐คฌ๐
After watching that display of a great, wry sense of humor, why the heck wouldn't I subscribe?
@retro80s80: https://youtu.be/fICMe0QvYrE?si=tbHcvVch8HALIHnY
@LenovoLenovo-g2f: This Fosi is for stupid buyers.
@Douglas_Blake_579 replies to @LenovoLenovo-g2f: As opposed to spending $5,000 to get similarly capable audiophile equipment?
@CleartoneAudio replies to @LenovoLenovo-g2f: Trolling...very nice of you.
@Douglas_Blake_579: From the Williston Labs channel, we now have confirmation that flipping the stereo/mono switch while the ZA3 is powered up is not safe . It puts the chip into protection immediately and we can't be sure it will always come back on after a power cycle.
That switch has no business being on the front of the amp, right in the middle of "Daddy what does this do?" land.
@mergru6371 replies to @Douglas_Blake_579: Chinese kids don't do things like that. They raise kids different. Not judging btw, I think Western society has a much bigger problem raising the youth
@ropeburn6684 replies to @Douglas_Blake_579: โ@@mergru6371 That's interesting from a cultural point of view, but irrelevant in the context of an internationally sold product.
@tubewatcher3100 replies to @Douglas_Blake_579: @@mergru6371 Far from being an admirable trait, "don't touch that!" is exactly why Chinese and South East Asians lack intellectual curiousity and creativity. It has all been beaten and screamed at, out of them since young. A human block of wood does not define a well behaved child.
@CristiBaciu: Imagine a version 2.0 with just HDMI input to connect to tv arc hdmi to control with tv remote
@ufopulse: cheap chinese junk that clips more then ur grandmas coupons before holidays
@Douglas_Blake_579 replies to @ufopulse: Nope. I have a TPA3255 based amplifier with clip and protection lights, here. My music collection is curated at -16db just like streaming services... and even with everything maxed out, the amplifier clips about once ever 10 seconds, on musical peaks.
For the record... that's 110 watts per channel and it's straight up freaking loud!
@neilw4569: I like the Grant Wood painting in the background!
@richardgrumbine4867: Looks like a great little amp... I would have liked to have seen a more standard on off switch... and perhaps no need for volume... and put the mono stereo switch on the back as I would think you would need to be touching very often if at all once you have it set up... but doing so inadvertently like have bad results!
@timwoodward3381 replies to @richardgrumbine4867: Yep...power amp only. no knobs, RCA/XLR, mono/stereo on the back ๐
@theman-pc2ej replies to @richardgrumbine4867: Power button is just fine..long push on volume knob and walah
@geevee1045: Enjoyed your interesting review. Thanks. Just wanted to add that the Fosi Za3 is the first cheap class D amp I've heard that reproduces male voices with body (elevated lower mids perhaps?). It actually sounds rich on my Kef LS50 Metas and manages to inject some warmth into my Maggie LRS+ speakers. So, this is a great relief compared to stereotypical class D leaness, in which hollow body guitars for example, sound like solid body guitars. Just received it today, but so far it's a very pleasant sounding amp. Well worth the cheap investment, for what you get in return. And the sub-out is a nice bonus too.
@JukeboxAlley replies to @geevee1045: What preamp are you using?
@geevee1045 replies to @geevee1045: I'm not using a preamp with it. I'm running a Dragonfly DAC from my laptop into the stereo Fosi Za3 (48v supply), then into my speakers. I've also tried setting the Fosi volume to full and also to 3 o'clock, while controlling the volume with a Nobsound ALPS27 (50k) volume control but didn't like the results.
Having lived with the Fosi Za3 for awhile now, I'm recognizing that it's not as powerful, hard-hitting and spacious as my cheap class A/B SoundArtist SA-200IA, which I prefer with my Maggie LRS+. Both amps were connected to a subwoofer. The Za3 is on the softish side and I'm beginning to wonder whether the warmth might possibly be a result of intentional 2nd harmonic distortion. Need to do further testing against my Aiyima A07.@@JukeboxAlley
@JukeboxAlley replies to @geevee1045: @@geevee1045 I would definitely recommend running a preamp on the za3, that would make a tremendous difference in gain and impact, always does, as it's still basically separates, the za3 by itself just isn't going to cut it, all of those need a decent preamp behind them.
@geevee1045 replies to @geevee1045: I ran a passive preamp with it, but I believe you're talking about an active preamp with gain. What preamp are you using with the Za3? I assume you're objecting to the NE5532 preamp and volume control quality in the Za3. Well, my Dynaco Pas3x tube preamp is presently out of commission, but I'll try the preamp section of my original NAD 3020, or the pre-out of one of my vintage integrateds when I get the chance, thx. @@JukeboxAlley
@geevee1045 replies to @geevee1045: I ran a passive preamp with it, but I believe you're talking about an active preamp with gain. What preamp are you using with the Za3? I assume you're objecting to the NE5532 preamp and volume control quality in the Za3. Well, my Dynaco Pas3x tube preamp is presently out of commission, but I'll try the preamp section of my original NAD 3020, or the pre-out of one of my vintage integrateds when I get the chance, thx. @@JukeboxAlley
@ShanePleasance: My experience with stereo and mono switchable power amps has been to have 2, but keep them stereo mode into biwirable speakers.
@hallmufc replies to @ShanePleasance: How that set up work?
@ShanePleasance replies to @ShanePleasance: Lets say you have 2 x 30 WPC stereo amps that can be switched to mono. Switching them to mono gets you a change to the total output power, and usually a change to the noise figures, not always an improvement. Power usually isn't the issue anyway. Take one stereo amp for each bi-wirable speaker. Y shaped RCA's from source, so one input RCA to 2 Output RCA's - one plug to left amp left channel which connects to the tweeter, other to the right channel of the same amp with connects to the Bass driver. Same with the other amp and speaker (right channel). Then you have - ostensibly - 2 x 60 WPC power amps - and can be done with any two of the same (or same gain) power amps, even if they are NOT mono compatible. Then of course you can have one stereo amp for tweeters, one for bass..... or consider dumping the speaker crossovers and exploring an active crossover twixt pre and power amps, but thats another video... ๐
@Douglas_Blake_579 replies to @ShanePleasance: @@hallmufc
Shane has it...
Remove the speaker jumpers.
Amps in stereo mode:
Pre0ut left -> za3#1 L+R -> za3#1L -> left tweeter + za3#1R -> left woofer
Pre0ut right -> za3#2 L+R -> za3#2L -> right tweeter + za3#2R -> right woofer
I just want to add a small note of caution here... the outputs of these amplifiers are in BTL mode. That is they are already bridged. You cannot connect the two black binding posts together, that will cost you an amplifier... So get a meter or continuity buzzer and check your speakers before powering this up, to be sure the bass and treble sections are fully isolated.
@markovlasic1978: 2 mono fosi ZA3 for 2 speakers as mono blocks
@earthoid: Decades ago I had two NAD 3040 integrated stereo amps that NAD made easy to bridge for mono so I did. Note: the 3040s already had twice the power of the beloved 3020s. Unfortunately the bridged sound was terrible and was only suitable for maybe a PA system. So I left that mess behind but still can't shake the nasty taste that bridging left behind. Therapy might be needed before I can bridge to mono again.
@Douglas_Blake_579 replies to @earthoid: I think you'll find things have moved on considerably since "decades ago".
@gregbailer8701: Fun Fact: this amp is $100 and gets hot. To all of the 48V( brick) "mono-block" dreamers beware. Your schitt gonna blow up at max level...very soon. It cost Fosi money to drill those holes. Must be a reason?
@Douglas_Blake_579 replies to @gregbailer8701: Naaa ....
@JC-xf5jc: Love thus GUY๐๐ผ
@sguttag: In the fun fact department...the XLR connector (which gets its name from Cannon where that was its connector type)...It was not developed as an audio connector, persay. Have you ever checked the specifications for the 3-pin version? 15A...a bit excessive for mere mic or line level audio! Even its voltage rating is up to 133V on the 3-pin.
@chinmeysway replies to @sguttag: three pin version? all xlr is that
@sguttag replies to @sguttag: @@chinmeysway Not at all. There are 3, 4, 5, 7...etc. 5-pin is popular with DMX lighting systems, for example. However, 3 pin XLRs have notably larger pins than their higher pin count version.
@TheRockerxx69: I love mono!!! I Need 6.
@Projacked1: How does it work with impedance dips at certain frequencies? Still struggling with that one. ๐ค
@Douglas_Blake_579 replies to @Projacked1: First ... way too much import is applied to speaker impedance variations. For the most part, amplifiers are voltage sources. As long as they can produce the required current, impedance is largely unimportant.
I have a pair of towers that dip to about 3 ohms in the upper bass region. Far as I can tell my TB10D, which is also a TPA3255 based amplifier, is unaffected by it.
@holycowmanheck: @10:56 The 20kHz sine wave seems to have a negative bias. The Vmax and Vmin don't seem to line up with what's shown. It looks more like 32V and 41V.
@Douglas_Blake_579 replies to @holycowmanheck: What do you expect from a $65.00 portable scope?
The display is not centered on 0 volts.
@robertbox5399: If you put 100W into those resistors without a heatsink, they most certainly will burn through that book!
@AudioMasterclass replies to @robertbox5399: Don't worry! I'm a quick worker.
@robertbox5399 replies to @robertbox5399: Until you forget the thing's been left on... The green ones change colour when they get properly hot and you can smell the warmth! Proper audiophile comment that.
@AudioMasterclass replies to @robertbox5399: And then the magic smoke.
@Douglas_Blake_579 replies to @robertbox5399: Sine wave testing is particularly brutal. Most amplifiers are not meant to sustain full on maximum power for more than a few seconds. So one takes their readings then lets things cool off.
I have pairs of those resistors on rather large heatsinks and I've burned fin marks into a piece of scrap wood while working on amplifiers. So far they seem to handle it well enough.
@robertbox5399 replies to @robertbox5399: @Douglas_Blake_579ย Yes, the difference between PA amps, guitar amps, and home cinema stuff. PMPO rules!
@thomaslutro5560: Orange knob.... Am I the only person suddenly thikning about US politics now?
@noelmurray1 replies to @thomaslutro5560: You know it should be a BLUE knob!
The only problem is it would cause too much distortion and interference.
Better to go back to the orange.
@riccitone: lol! No โkโ ๐
@LucienBill: The unboxing music is the perfect level of loud and annoying ๐คฃ
@AudioMasterclass replies to @LucienBill: I aim to please.
@4ujase: Oh my goodness, I upgraded my Fosi V3 to the 'C'est magnifique Atoll IN100SE! What a sublime amazing sounding beast of an AB amp but not cheap. Two ZA3 in mono I would have considered in a heatbeat, if only it had come out sooner.
@fosiaudio replies to @4ujase: Fosi audio's fault!
@ENGLISHISBEST: This is audiophile stuff . I enjoy music more than the inners of technology, thats why I buy hifi equipment of hifi quality off the shelf, they do all the technological thought processes & design as its their career. I open a magazine & go on internet to see what is the best rated for the money I have for a component with no real headache worrying about what makes it tick. I then sit back & enjoy my music rather than assessments of the machine. It's when you read comments like you need a machine that reads 10 farads you know it's O.T.T.
@edmatzenik9858: Mono is sadly lacking in many setups. I think you particularly need a mono switch in a car because not everyone can sit in the middle. And as for cross-talk, in some rooms I've longed for that. In some rooms you just have to put the speakers too far apart, so a bit of cross-talk could be a good thing if you could control it. Maybe.
@PlatinumMastering: Itโs true some amps have very big crosstalk โฆ and yes 2 mono blocks are better
@paulfriedman4767: You Sir, are informative and entertaining.
Bravo
@sjors01: Hi Audio Masterclass, the back is much more interesting you said, than the front, but the inside is even more beautiful and educational. Could you include this in the next reviews?
@thelowprofile9767: How do you set it up as monoblock considering that it has left and right rca inputs? Do you just use either the red or the white rca for input?
@Douglas_Blake_579 replies to @thelowprofile9767: The back of the amp is marked ... you use only the right speaker terminals and only the right input channel.
So a dual monoblock setup looks like this...
Preamp out right -> za3 #1 input right->speaker output right->right speaker
Preamp out left -> za3 #2 input right->speaker output right->left speaker
@thelowprofile9767 replies to @thelowprofile9767: @@Douglas_Blake_579 thank you so much. Exactly what I wanted to know. I asked the same question to another vlogger but he canโt seem to understand the question. But you got it right away and answered it in a very clear and detailed way. Youโre the best.
@thelowprofile9767 replies to @thelowprofile9767: @@Douglas_Blake_579 Hi, was this documented anywhere? I was watching another review although it was for another brand which is Aiyima A07 MAX. The reviewer says that he uses the left input instead of the right input. I understand that they are different brands but just wanted to clarify. Ultimately, if I had to set up a monoblock configuration, I can try either left or right input.
@Douglas_Blake_579 replies to @thelowprofile9767: @@thelowprofile9767
Input/output choice in mono mode is not a function of the chip itself, so different designers can implement this differently. Best advice: follow the manufacturer's instructions.
@thelowprofile9767: The knob will match the Klipsch speakers.
@improbablehandle: Thanks for that handy nose hair trimmer link.
@Jan-ic9iq: I have the Fosi V3 with 48v powersupply , hooked it up to JBL L90's ๐. To my amazement it is capable of handling them. It does get warm, the powersupply stays cool. Two ZA3's would be nice to let those drive the L90's. Unfortunately you can not do bi-amping as far as I know.
@marklawrence17: I'm an EE. I've had superlative stereos since '79.
Bridged amps, which this is not, deliver twice the voltage and therefore four times the power. The price is each side of the amp sees half the speaker impedance. So, for example, if you bridge into 4ohm magnepans each side of the amp sees a 2ohm load. Few moderately priced amps can reliably handle a 2ohm load. So bridging is for high impedance speakers that don't drop much below 8 ohms. Few modern speakers fit that description. I've never been a fan of bridging. You're all too likely to have stability and overheating and current clipping problems.
Paralleling, as this amp does, results in each side seeing double the speaker impedance. For example, when driving our 4ohm magnepans, each side of the amp sees an 8ohm load. This is much easier for most amps to handle.
You would run this amp in mono mode to handle very low impedance speakers. I've seen some speakers drop below 1ohm in the audio band, dropping below 2 ohms is not uncommon, dropping to 3 ohms is rather common. This amp in mono mode would be a good choice for such speakers, and a lot cheaper than an ampzilla 500 or a mark Levinson.
On the other hand this amp in mono mode would be wasted on a high impedance high sensitivity speaker like any Klipsch. There would be twice the cost and no benefit.
All these considerations really only count if you play your speakers loud. I have a small stereo in my bedroom which averages about 50db never gets over about 80db. Power considerations are just silly.
This amp in mono mode would be a decent choice to drive the magnepans in my living room, which sometimes get quite loud. However, in mono mode each side of each amp sees an 8ohm load and that results in the minor high frequency rise of a couple db. Personally, at age 68 I can't hear anything over about 11khz and I've never measured anyone my age who can. Few over 25 can hear above 16khz, and few under 30 can afford a stereo that works well over 16khz. I've measured several dozen people. No one over 15 in this country can hear 20khz. You may have ribbons that go to 50khz or plasmatronics that go to 200khz, but you can't hear it.
I have trouble imagining someone with $20k speakers using this amp in mono mode. But for my bedroom stereo, elac ubr62 playing soft music, this amp in stereo would be a good choice. For a budget stereo with ss-cs5 or bs22-lr or elac debut 5.2 or emotiva b1+ or Klipsch r41m or rp600m, this amp in stereo would be a very appropriate choice, IMHO.
@robertbox5399 replies to @marklawrence17: I'm an EE. What is current clipping? Shouldn't high current cause the feedback loop to increase the drive, ending up with voltage clipping?
@marklawrence17 replies to @marklawrence17: @@robertbox5399 you're correct if the power supply can keep up. If not you get clipping at a lower voltage than you expect. Which some of us call current clipping, as the solution is a power supply with more current capacity.
@Douglas_Blake_579 replies to @marklawrence17: You need to look up the TPA3255 spec sheets ...
The chip itself natively supports ...
4xSE -- 4 single ended outputs
2xSE+1xBTL -- 2 single ended and one bridged output (2,1 stereo)
2xBTL -- 2 bridged outputs (stereo)
1xPBTL -- 1 Parallel bridged output (mono)
The base mode for stereo in these chinese amplifiers is 2xBTL ... that is each channel is already bridged.
For the mono mode they reconfigure the chip for 1xPBTL or Parallel Bridge Tied Load as a means to increase output current capacity.
@marklawrence17 replies to @marklawrence17: @@Douglas_Blake_579 I search my soul and I cannot find that need. Curious that we've never met, yet you claim to know my needs better than I do. . .
I'm not interested in the chip at this instant. We're talking about the ZA3 box. Perhaps it's already internally bridged, which means external bridging is not available. David asked if an EE would explain bridging v. parallel. I did that.
@Douglas_Blake_579 replies to @marklawrence17: @daleboylen6427
Sorry, but I thought you would want to speak from a position of knowledge ... I won't make that mistake again.
@mcgovernjimmy: Lots of infomercials about this product today among "reviewers". "Review for sale"...
@AudioMasterclass replies to @mcgovernjimmy: Fosi Audio sent me this amp. There is no payment or sponsorship.
@mcgovernjimmy replies to @mcgovernjimmy: @@AudioMasterclass Many, like yourself, have been organized by the manufacturer to talk about this product... with the obvious goal of the manufacturer to generate buzz and increase sales. You also stand to profit - which is fine... just be open about it. It would actually be more notable if you spent your own money on the amp. The fact that they sent it to you for free, and these videos happen in unison, is unseemly. It undermines your credibility and puts you in the position of being viewed as being on a bandwagon and "available for hire". This highlights a fact that people need to remember... reviews are just the perspective of another person, and they don't necessarily deserve the credibility that people assign to them. ย
So many videos about this product suddenly popped up... it's just creepy.
@Douglas_Blake_579 replies to @mcgovernjimmy: @@AudioMasterclass
_ "Fosi Audio sent me this amp. There is no payment or sponsorship."_
... other than a free $159.00 amplifier.
@Douglas_Blake_579 replies to @mcgovernjimmy: @@mcgovernjimmy
" Reviews are just the perspective of another person"
Not really ... Reviews are straight up advertising .
@pauln6803 replies to @mcgovernjimmy: @@mcgovernjimmy This is how Chinese brands get their products known without spending silly money on advertising and paying for What HiFi review stars.
If you've followed Amirm of Audio Science Review, you'll know that he has said he has good relationships with some of the Chinese DAC companies (ASR cut it's teeth on bench testing DACs).
He's said they reach out to him and send products for testing and are happy to answer almost all the technical questions he has thrown at them (ASR is a measurement based community review website, not "audiophile" fluff pieces) and are open to criticism/suggestions for designing the next generation.
The WiiM streamers exploded in popularity because Linkplay threw them at YouTubers.
I can't say that Linkplay were the first to utilise social media platforms in this way, but the rest have certainly cottoned on to this marketing tactic.
@jbrc1322: One feature missing here that would take this amp to the next level is a high-pass filter for the speaker outs when using a subwoofer. This would take a huge load off the amp if the high demand from the passive woofers was reduced. Distortion would drop substantially at high listening levels and there would be much more headroom for harder to drive speakers. But.... a little birdie told me I just might get my wish in the not so distant future.
@fosiaudio replies to @jbrc1322: Cant agree more.
@deareeMusic: Your sarcasm has reached levels where I have no idea when u are for real and when u arent and I want to keep it that way
@JayBeezy31 replies to @deareeMusic: Sarcasm level 9,000 , music enjoyment level, 10,000 !
@jz6373 replies to @deareeMusic: You really need enough power, processing, and separation in the mid-range to parse the dimensionality of his sarcasm. With the right atmos/ Dirac setup you can literally hear it coming.
@samlee2562 replies to @deareeMusic: Welcome to England ๐ค
@deareeMusic replies to @deareeMusic: @@samlee2562 haha best response
@DiscipleRay replies to @deareeMusic: You just have to understand British humo(u)r!
@mariokrizan399: ๐๐๐๐๐๐๐๐๐
@SubTroppo: The outro music didn't make me want to do anything nasty; which is nice. How hot does the power supply run?
@rabit818: If your fingers has peanut butter while turning it on, fingers slip and you turn the volume loud.
@AudioMasterclass replies to @rabit818: This is a problem I will never have.
@AudioGuyBrian: Good amp maybe to build a garbage can boombox with. LOL.
@jasontimothywells9895: Sir , one does not have to have two amps , for your old enough to remember when it was mono . ๐
@tonyfrench2574: He loves himself and all that irrelevant verbiage he generates
@AudioMasterclass replies to @tonyfrench2574: Who, me?
@rhwinner: I once caught mono at sleep away camp.
@ThaVoodoo1: I will be sticking with my Class AB power amp thanks.
@fosiaudio replies to @ThaVoodoo1: Haha, in which case you may turn to class amps?
@gomiwomi replies to @ThaVoodoo1: No one cares.
@fthfhhdf replies to @ThaVoodoo1: it's outdated