Dual Mono vs. Monoblock amplifiers

Is there a difference between two independent amplifier channels in a single chassis vs. a true monoblock amplifier?

[@Antoon55]

Maybe it depends on the quality of the amp. A high-end stereo amp might sound better than lower tier mono blocks. I have a 25 years old Krell KST-100 stereo power amp in my system. This year I started a project to modernize my old system. I tried various system changes and ended up with buying a nice streamer/dac/pre-amp and a a recap of the Krell power amp and a recap of the filters of my Duntech speakers. I compared some modern mono block power amps with my old Krell and every time I'm astonished by the performance of the old stereo Krell.

[@eyelovelil]

I have the Aragon 4004 dual mono amplifier your writer mentioned which I’ve had for 32 years. I bought them while stationed in Germany from dealer Lothar Wegner & for the money & as a used product they have been well worth it. I have thought of upgrading, so to speak, but as satisfied as I am with them I’m more likely to upgrade the amps themselves. Thanks for your video & as always I walk away more knowledgeable than I were at the start. BTW, I took your advice & moved my system from between my speakers 🔊 & I am now in HOG Heaven of what a difference it made. Keep sharing the knowledge.

[@jeffwalther]

That was an excellent explanation. I wish I could visualize electronic circuitry that well back when I did that stuff.

[@bassieadriaan4278]

kzbin.info/www/bejne/paeZZ2yue8uiqck

[@high16200]

Thank you sir for a nice review on these amps.

[@savvassidiropoulos5952]

I view mono-blocks as the good way to go when power requirements start to become serious. Transformer size and weight as well as heatsink sizes tend to become simply un-manageable to merge two of these in a single chassis. That chassis would need to be hefty in its own right just adding more size and weight to the system and then moving one of these would be a project by itself. And, of course, two monoblocks sitting by the loudspeakers solve the issue of cable lengths from the power amp to the speakers. Much simpler to transfer line level signals over longer cable runs.

[@MICHAELMG62]

Paul, I expect you will know about this but in case you don't this is a fantastic example of what your describing Mitsubishi DA-A15DC I have and use one "amazing sound"

[@flashnc]

Good news :) , in my land PS audio doesn't reach here so I have to opt for other brands and one of them that impressed me and compare well with brands like Denon, Nad, Cambridge etc is what I have now the ATOLL IN200 Dual Mono ... and the result on the same speakers is simply incredible... from the smoothness, the deep and strong bass, and soft mids.. a brand that didn't pay attention and after testing it.. just said WHAT HAPPENED HERE !! Top And by the way congratulations on your company and quality... and for the excellent tutorials and tips you make... may the king live many years

[@donalddeorio2237]

I have an Adcom gfa 535 which has two transformers, two sets of storage capacitors and two sets of transistors but a single power cord. It's pretty hefty for one rated at 60 watts per channel, it does sound good

[@CraftyZA]

It kind of makes sense. However, the power distribution solution of your choice, still comes from a single power source. The NAP250 I build a few years ago was built in duel mono. Each channel has it's own 500VA toroidal transformer, it's own power supply board, and it's own speaker protect. When you plug in 2 mono blocks, the power still comes from the same source. Also the signal path is a good 15 inches apart for each channel. Lastly I have over spec'd the capacitors in the power supply in order to make sure there is always enough power and no ripples can be introduced.

[@CaptainJamesTKirk-en4kt]

I agree with Paul, any separate chase will help with isolation, so most Int. Amp don't sound better than most Monoblock, but they get very close in sound when you go the dual mono bloc. This is going to depend on how it's made as well. That's why I like dual mono Int. Amps are better than stereo Int. Amps, if built well they can sound very similar to separate monoblock, in some cases doing A/Bing most people can't tell the difference in "hearing" per se. I compared recently a pair of Monoblocks, compared to an Int. Dual Mono, which is about 99-95% of the sound of monoblock amplifiers.

[@swinde]

At one time I had a Marantz Model 15. It was a dual monoblock with a common faceplate. It is an excellent amplifier, but does not like 4 ohm loads.

[@michelkh87]

The HK 990 is a great example for a true dual mono with 2 seperate toroid transformers for each channel, and a seperate 3rd transformer for the preamp and the dac section. This integrated amp can literally drive a trailer!

[@BoudewijnvanHouten]

Nice follow up indeed. I reacted on your first post stereo- vs monoblock amplifiers not knowing that you also did the logical follow-up on this matter. As said I had a Levinson ML-3 and Krell KSA-100 which were both dual mono's amps and the biggest disadvantage was probably their weight because of squeezing two already potent psu's in one chassis. I now have a Conrad Johnson Premier One b tube amp that weighs in even more than the Levinson ML-3 I had which was almost not reviewed by the late J. Gordon Holt of Stereophile due to it's weight which exceeded his own weight. How insane is that having an amplifier that weighs more then you do yourself. Gordon argued that Conrad Johnson should have split this amp in two monoblocks to make it more manageable. 65 lbs should be the max. weight for an amplifier he stated. That and the fact that you can place monoblocks near to your speakers to have a shorter ls cable where the by far the most current flows would be another pre for monoblock configuration. Money wise though is that with a dual mono you only have to pay for one chassis and with mono-blocks for two. Chassis and cooling elements are expensive items built by professionals almost always outsourced by the manufacturers so they are factured in into the total price.

[@rayhunter7371]

I agree with Paul. In the 30+ years I have been into HiFi I have found the same. Generally speaking, monoblock amps are best, but dual mono is closer in performance to monoblocks than they are to stereo amps sharing a PSU. If one is on a budget and/or lacks the space but still craves performance, hunt around for a good dual mono.

[@rayhunter7371]

@British Naturalist awesome. So each amp is driving a speaker? I can do that with my Plinius SA-50's because they are essentially stereo amps with the bridging feature built in, which I don't have to use. I would experiment with that if my speakers were bi-wire able.

[@rayhunter7371]

@British Naturalist yes that would be what I would try. Like you say, vertically bi-amping so the channel separation remains. I drive my amps with XLR's so would probably need y-cables to feed 4 inputs instead of the 2. Only the 2 on the preamp.

[@raphaelmeillat8527]

Super clear as usual! Thanks Paul for this.

[@WimHulpia]

monoblocks are better mainly because you can put the closer to the speakers, reducing cable lenghts from amp to speaker. With a dual mono amp you need more cable.

[@odis929]

It's far better to have longer speaker cable than signal one!

[@sc0or]

IMHO the best combination is 4 mono blocks that allow bridging. When you have speakers with bi-wiring, you can select amps that match lows/highs the best (of course the amps must support easy transistors PCB replacement). Or you can bridge identical ones and feed more powerful speakers. Or any other combination. Krell, Leach, CFA - you name it. As gameboy cartridges. It's not difficult. All you need is standardized mounting points. They are huge because bigger cases are better sold. But take a look at Quad for instance. Something like this. 50-100 Watts per mono 1/2 channel is enough. A small heat sink and a silent 90-120mm fan are optional to make them really compact and replaceable.

[@heywoodjablome5630]

I didn't immediately recall the difference between the two, despite owning an excellent (refurbished with all new parts) Australian Modular Electronics ME850 dual mono amp. It also explains why there is not much difference between the ME850 and the Parasound JC1 monos, at least at the levels at which I listen.

[@Foxtrot1967]

If having multiple channels crammed in a single chassis was so bad, I wonder why the Highly Renowned Denon POA-A1HDCI Reference is STILL one of the best produced. Follow the money people.

[@brentcollins9727]

Never heard of it. Lol

[@ZeenFang]

Hi Paul, I have a silly question here. Can you use or is it better to use 2 sets of monoblocks (4 of 1-channel monos) to drive 1 set of speakers as a by-wire and by-amp connection? Where, 1 set of the mono amplifiers drives the mid to high frequency and the other set of the monoblocks drives the low frequency? Cheers, Zeen

[@arcorob]

Great video. Now I have to search your channel for why monoblocks are better than stereo :-)

[@viktor928]

Is it a good idea to bi-wire my Infinity Alpha 50 speakers with two bridged stereo mono blocks? To be more exact I have 2 NAD 2200 pe and one NAD 1155 along.

[@heronvontremonia9975]

if you are in a country that has a 3 phase system , it would be also beneficial, to make sure, that the two amps are on different phases.

[@kencohagen4967]

Two monk amplifiers would provide better stereo separation. Your still going to be limited by the source fo the signal to be amplified. In other words if you have a crappy DVC/CD player and it only has a stereo separation of 60 db, it wont sound as good as one with 90db of separation. The same for turntables, cassette decks, radio preamps for AM and FM r exception. Now I have a Ustinov for Paul. For my guitar amplifier ad rack mounted effects I have a firman line conditioner and voltage correction. Should I use one of these to make sure the input voltage is correct and conditioner for noise elimination in the power line. I also have a huge line conditioner from a old main frame business computer. I’ve actually have two of them but one should be enough. Would it be a good idea to use one of these? Thx!

[@jondrake890]

paul what do think emotiva h-c1 monoblock amplifiers

[@mtabernig]

Yes, however the power cords goes to two separate outlets on the same plug that goes to the same wire that goes to the same breaker on the panel. That argument is all snake oil, you plug both individual amps into the wall both using the same breaker. What is the difference with 2 amps in 2 separate chassis with 2 independent power supplies in again separate chassis ??? The common denominator id the power cord and the cord is normally more than adequate to carry substantially more current than what the amp will utilize. One cord or 2 cords all go to the same breaker using the same wire in the wall.

[@Littlelewie151]

As far as I know the amplifiers are isolated from the line voltage in the power supply, but I dont know.

[@beslemeto]

Absolute nonsense!There is no difference between dual mono and mono amps in my opinion and i prefer dual mono due to better mobility!

[@beslemeto]

Hello guys i have a question! Can i perform bi-amping with dual mono amplifier? I have Yamaha MX-1 and i want to bi amp some Infinity speakers with them.Thanks in advance!

[@backrack01]

Whats the big difference between bridging two power amplifiers into mono compared to having mono block amplifiers? Just less noise?

[@leowetzel2497]

Paul, Back in 1974 I was a 14 year old audiophile, however I didn't have the financial resources to buy a system that was satisfying to me, but I did have a halfway decent stereo which had a AR-1a turntable. Fast forward four decades, I lucked out at a estate sale in North Carolina and I bought the system that I wish I had in 1974, but this great deal included a receiver and speakers from 1974! I absolutely love it, and feel they were reconditioned because they look and sound like new! The receiver is a Sansui Eight Deluxe and the speakers are Heil AMT-3 Rock Monitors. I added a Crown AB type amplifier with 450 watts RMS per channel. Do you think that this is a decent system for someone who still lives on a shoestring?

[@chadbarker4023]

Hell yeah! I mean no. You need to sell it to me. Hahahaha

[@connorduke4619]

What I find interesting how large and expensive power amps can be and how much anxiety audiophiles spend on them... when speakers, dacs and preamps impact the sound more. And further that most preamp-power amp (dual or mono) struggle to match the performance of a humble Marantz integrated amp which - I can attest to from years of experience - makes even poorly recorded Rolling Stone albums sound engaging.

[@AT-wl9yq]

What I find interesting is why people like you just make stuff up and act like you know what you're talking about, and are not able to back up one word of what you say.

[@connorduke4619]

@@AT-wl9yq I've owned a lot of Marantz amps, there ya go buddy.

[@AT-wl9yq]

@@connorduke4619 Like I said, you can't back it up. If you could, you would have already done so. OK Buddy.

[@connorduke4619]

@@AT-wl9yq I had Marantz amps for years and Rolling Stones albums for years, they always matched well. Only later I heard of folk unable to play Rolling Stones on their high end systems because the amps playing the leading edges of Keith's guitar too harsh. Design legend Ken Ishiwata always found a solution to let Marantz amps play clearly but without transient harshness. That is more than enough backup , matey, I rest my grounding box

[@mauanderuk]

Takes a hack saw to my dual mono amp (it would still work!) no difference but like all things this would be model dependant. You mention noise but not about crosstalk one of the main benefits.

[@allansh828]

also think about long power cable vs long interconnect

[@thespotlightkid4138]

It definitely seems worth paying for the extra chassis of two monoblocks compared to the dual-mono 1-box amplifier where each channel's signal path is in close proximity of two power-supplies & share one mains input. P.S. Years ago i saw a Brit hi-fi mag's review of a dual-mono amp with separate IEC mains inputs (unique?), i can't recall the name but i don't know why they didn't go the whole monoblock hog ...being so obviously determined for each channel's power independence.

[@bingoberra18]

At what pricepoint do monoblocks start to make sense? I mean, I´ve been eyeing up the Hegel H190 at ~$4k. Would two monoblocks for 2k each make more sense? Or at what point can we say that two monos start to become a better package than a single? Also, do monoblocks make more sense for floorstanders, and less sense for bookshelf speakers with an active sub, or is that irrelevant?

[@microteche]

Good point, a single stereo amplifier could sound much better than 2 inferior mono blocks depending on the specifications and build quality. I have not ventured into purchasing mono block yet but if I did I would theoretically expect to double my budget for decent monos compared to the stereo power amp price that I would say is in my budget.

[@ryanschipp8513]

Great questions but I doubt Paul is going to answer anything. He never does

[@hugobloemers4425]

@@ryanschipp8513 It's that 1% that's missing.

[@bingoberra18]

@behexen250 Sure I´m just looking for some kind of benchmark for when you even get a decent mono setup. I think you need to get to a decent amount of money before even considering it, and at that point the powersupply might not even be a limiting factor yet. Lets say the PS audio monoblocks you get for 5 grand a pair. Now it would be interesting to compare them to a 5 grand poweramp or a 6 grand integrated amp for example. While at 3 grand you might not even get any monos to talk about, while you get a pretty decent integrated for that money, and maybe at that level the roughness of an integrated vs. monos hasnt started to show yet.

[@jimfarrell4635]

I went from twin Shanling monoblock 80watt tube amps to a dual mono DK design VS1 reference Mk III with two giant transformers and twinned tube preamp sections. The DK design is better ( which is why I still have it after 15 years) but its a much more powerful beast and, of course, partly solid state. I dont think you can really generalise. Too many factors to take into account. Of course one disadvantage is that the dual mono weighs something like 80lbs and is murder to lift. Its interesting that premium brands like Hegel seem to have chosen not to go down the monoblock route. In fact I might be wrong but I think they only make stereo integrateds. ( that could be bullshit but I dont remember seeing any reviews of pre/ power or monoblock models ).

[@irashapiro9189]

What about a dual mono with two power cords? Any input? I have seen them but can't remember the manufacturers.

[@louisperlman8030]

Gryphon Mephisto is one.

[@badrumurphy3813]

Carver had one; TFM-75

[@ThinkingBetter]

Looks like a Mac Mini from a decade ago. The new Mac Mini M1 is great as media player with a good DAC.

[@eliashabash7591]

The problem is there are duel mono designs with 2 separate power cables

[@vonclod123]

My dual mono has left and right power cords Carver Lightstar Reference 1

[@mikecoffee100]

Good Answer Good Answer just like in Family Feud ;)

[@badrumurphy3813]

Carver TFM-75?

[@veryunclear]

Any amp that makes ears bleed gets my seal of approval. :)

[@classa50]

And If u use 2 separate AC-inlets?? Like you would have with 2 mono's? So only the Case itself is the common thing..

[@aexetan2769]

Why is there money on the upper right corner?

[@Aloha96789]

If you were to do a blind taste test with nice bookshelf speakers and a nice powered sub would you be able to prove the monoblock system sounds better? Under these conditions I wonder if the argument would really hold up.

[@beslemeto]

Absolutely no difference between dual mono and mono!

[@Gez492]

Why are there no monobloc pre amplifiers to my knowledge? I have a Roksan platinum series dual mono power amp with a huge Toroidal transformer bigger than the combined power of many so called "high end" mono blocs I feed it regenerated clean power. It is astonishing, has so much headroom and dynamics but it should given its build quality and it be takes two people to carry it. Cost 7.5k GBP when new, lucky I got it 2nd hand😜 point being it will run most monoblocs as close as its not worth the hassle.

[@shaynakash4222]

dual mono with separeted power suplly to each side like two different mono blocks but the transformer must be one if you dont want any delay difference even if its very minor....

[@PapaWheelie1]

How does DC have delay?

[@shaynakash4222]

@@PapaWheelie1 realy?the transformer puts out AC . the power supply makes it DC.... ON AC THERE IS ALLWAYS DELAY......

[@PapaWheelie1]

@@shaynakash4222 - that’s why the designers used dc components for the amplifier section. Once it is rectified it doesn’t matter what the phase is of power before the diodes.

[@bocolis88]

Naim Audio has a different approach with a dual mono design using external power supply housing (e.g. NAIM NAP 300DR). In this case you have the benefit of removing the noisy power supply module not only from affecting the other channel but both channels altogether. What’s your take on that? They went so far and stopped production of monoblock amplifiers (except for the money-no-object Statement line) because they found it made no difference. Instead they have active crossover options for specific speakers where 3 stereo amplifiers are used to power each speaker section with better results than passive monoblock driving.

[@halpearson4226]

A single 'overkill' transformer with an almost-insane 1st large reservoir cap (or cap array) in one chassis will work great with mono amps on separate boards in another box (1m away) +provided+ that there is significant and separate local decoupling (reservoir) for each amp and negligible inductance between the PSU and the amp boards. This two-box solution works better than single-box monoblocs, IMO, because the transformer and rectifiers aren't in the same box spewing and inducing noise into amp boards. Would a 4-box solution be better? Probably.

[@joelyoung3019]

Would using two separate 2 channel stereo amps bridged for two speakers, be the same as 2 monoblocks going to 2 speakers?

[@scottyo64]

Really once I went to monoblocks I won't be going back. Bridging is not the same.

[@YuengsNwings]

I think general acceptance is that vertical bi-amping is better than bridging stereo amplifiers into mono. If your speakers do not have the required binding posts for bi amping, then properly designed mono blocks will outperform stereo amps bridged to mono.

[@nightflyght5102]

For exactly the same budget, I'm not sure 2 monoblocks are better than a dual mono.

[@ThinkingBetter]

If the sky is the limit concerning your budget, go for discrete mono amps. For any actual budget, you get more per Dollar when you don’t need to pay for twice the cost of enclosures, certain of the electronics, packaging, manufacturing and shipping. Designing a stereo amp with careful power supply L/R separation for avoiding any perceivable cross talk is not rocket science.

[@HareDeLune]

Good advice.

[@ThinkingBetter]

@Fat Rat Yes of course. If the transformer has enough headroom and enough capacitance is used, it can do two channels well. When a transformer is dropping voltage at high power, it is not just causing L/R issues but also issues with that channel itself. Further up your electric grid, one transformer drives both channels and nobody talks about having separate grid transformers per left/right channel, right? 😎

[@ryanschipp8513]

Paul, so I have your Stellar s-300 Poweramp. I also have a pair of red dragon audio m1000 monoblocks. So based on this video The Red Dragons are way better than your Stellar amp?

[@JDG1971]

I Love High-end monoblocks Oohh yeah ✌

[@Xantylon74]

1:09 Don't compare apples and oranges! ^^

[@MAYDAYDEEJAY]

I think the question was referring to "cross talk" of dual-mono Vs two separate mono-blocks. And I disagree with Paul. My Dscope 3 can measure cross-talk down to -130dB, survey done by Klippel says that most of the experienced listeners (based on 25k ppl) can't hear below -40dB then I don't really believe that the difference between dual-mono and separate-mono can be heard if for example dual-mono would have cross-talk in the range of -80dB. But as always, we all are allowed to have own opinion. All the best from cloudy Scotland :)

[@HareDeLune]

I completely disagree with you and believe that you're taking the wrong approach, as well as espousing wrong-headed thinking about the subject. However, I *do* like Scotland. : )

[@HareDeLune]

@Fat Rat There's far more to Scotland than haggis, Mr. Vegemite!

[@HareDeLune]

@Fat Rat Wot? Me, a troublemaker?! Tsk-tsk. I'm as friendly as can be. 😇 😏

[@ChrisSmith-tc4df]

And don't forget the cross-talk within the stereo source. Some high-end DAC's have a surprising amount of L/R crosstalk despite their impressive single-channel specs. (Their banner specs are nearly always measured one channel at a time.) Although one always wants to minimize signal degradation, it doesn't make sense to plow an excessive amount of money into discrete mono block amps if one's source doesn't also support that degree of separation.

[@akeelshah7904]

I run a duel mono power amp and preprocessor i feel like most ppl would have the opinion as me that going from duel mono to monos wouldn't be as important now speakers and room accoustics yes definitely yes then go full mono

[@PapaWheelie1]

Dudes in the comments of every video this man makes: I have a blah blah blah with xtzzz blahs and yyz things. Humble brag humble brag. Tell me I’m awesome....

[@PapaWheelie1]

@Fat Rat - it’s a joke bro, settle down. What kind of gold plating cleaner do you use on your rca connectors?

[@spacemissing]

Why not go all the way and have your power company install a separate distribution transformer for each of your audio channels? Look, people, unless you have an outrageously overpowered system, it all comes from the same circuit, so any voltage sag caused by one channel will Still affect the other. There are reasonable demands and there are Unreasonable demands. Most of the demands made by audiofools are At Least Unreasonable and some are Just Plain Stupid.

[@spacemissing]

@behexen250 I like to point out how ridiculous some of this stuff is. My own components (far more than one system's worth) are mostly decent consumer-grade pieces, not high-end, and I am quite satisfied with the majority of them. Only on Very rare occasions do I have a chance to hear music I like on more expensive equipment, and when I do it usually makes recordings with which I am quite familiar sound utterly lifeless and unlistenable. I might wonder why, but at the same time I don't care because I would never buy something that had a bad effect. As an aside, I live in Santa Maria, CA, where PS Audio began, and I visited the place a few times. While I don't exactly remember meeting Paul there, I'm sure I did, so there is a nostalgia factor involved, and I find his pronouncements interesting whether I agree with them or not. In the end, this is all about entertainment and it must not be taken Too seriously.

[@dandonna852]

ATI AT6000 has 2 power plugs going into 1 chassis but has 7 channels?!

[@jamesplotkin4674]

Superior preamp and self-powered speakers provide optimal isolation.

[@rammisframmis8588]

If two 'monoblocks' are plugged into the same AC power circuit, then they are not 'monoblocks' anymore. What this is doing is STILL having common 120VAC to both amplifiers - the same thing as a single AC inlet plug on a 'dual monoblock' amplifier. The best that a home user can do is to plug each monoblock into a separate phase of the incoming AC line. There will STILL be coupling between the phases though because each phase is wound on the same transformer core on the power pole. There's nothing which can be done about that. In the end, all of this is a non issue except for the most horrible designs of power amplifier, and in the event that you have a crappy power amplifier, you probably aren't all that concerned about all this anyway. All of this is red herring stuff. I understand that PS Audio is in business to make money, but customers should be aware that practically all information in videos such as this are 90% marketing. For some reason, HiFi seems to attract more than its fair share of marketing hype, which is unfortunate.

[@KillerKiller655]

So funny what audiophile s believe ... Is like suoer car fans ......