Why use monoblocks?

[JustAnAudioLover]

Hi there!

I have what may be a silly question, but I'm genuinely curious.

Let's say you have want to have 100W for each of your two speakers. You could use:

* Topping PA5 II: 2x 100W
* 2x Topping B100: 2x (100W each)

In the end, you get roughly the same amount of power (based on these products' specifications). But the PA5 II route will get you there with a single device for ~$180, while the B100 route will need you to handle two devices, and for an amount of ~$600.

My question is: why use monoblocks at all?

It's inconvenient (two devices instead of one) and more expensive (at least in this example). Even if you want to power more than 2 channels, you could just buy multiple PA5 II and get more output power in mono mode than each B100.

I'm sure there's a very good reason for these monoblocks to exist, but I can't figure it out.

Could someone enlighten me? Thanks !

 

[Blumlein 88]

One reason is if you want to put the amps right near the speakers so you have short speaker cables. Or if such an arrangement fits the space better. There won't be any sound difference if amps are of about the same power capability for your speakers.

 

[JustAnAudioLover]

One reason is if you want to put the amps right near the speakers so you have short speaker cables. There won't be any sound difference if amps are of about the same power capability for your speakers.

Good point. But having shorter speaker cables would mean having larger RCA cables, so what's the point?

 

[Sokel]

Good point. But having shorter speaker cables would mean having larger RCA cables, so what's the point?

That's the reason most monos have (or at least they should) balanced inputs.

 

[SorenTyson]

I like mono blocks as they remind me of days of yore

 

[Blumlein 88]

Good point. But having shorter speaker cables would mean having larger RCA cables, so what's the point?

Long enough speaker cables with speakers might alter the frequency response a little. Longer RCA within reason won't. They might pick up some noise though usually not. As Sokel said a good reason monoblocks would have XLR inputs. In most circumstances either is capable of working just fine.

 

[boxerfan88]

monoblocks -> almost total channel separation

*almost because they’ll still share the power grid

 

[JustAnAudioLover]

monoblocks -> almost total channel separation

*almost because they’ll still share the power grid

Is there a real audible improvement compared to integrated stereo amplifiers?

 

[Purité Audio]

No, provided the amplifier in question can properly drive the loudspeaker.
Keith

 

[Overseas]

Probably monos are more versatile in a multi channel system, you can use them in various scenarios.

 

[Overseas]

Is there a real audible improvement compared to integrated stereo amplifiers?

Except separation, no. Still, many established brands boast about their double mono designs for stereo amps. Not sure if balanced design is the same with double mono.

 

[boxerfan88]

Is there a real audible improvement compared to integrated stereo amplifiers?

I don't care

I am just stating: monoblocks -> almost total channel separation

I am not walking into the audibility trap ... that might trigger a barking session.

 

[Apesbrain]

My question is: why use monoblocks at all?

They look cool.

 

[Sokel]

Except separation, no. Still, many established brands boast about their double mono designs for stereo amps. Not sure if balanced design is the same with double mono.

There is an advantage, at the high power ones, thermals.
No matter the class.

 

[mhardy6647]

One reason is if you want to put the amps right near the speakers so you have short speaker cables. Or if such an arrangement fits the space better. There won't be any sound difference if amps are of about the same power capability for your speakers.

That's not a very audiophile reason, though!
@Apesbrain gets closer, I think. Plus, you know, someone made more money than if they sold you one stereo amp.

 

[audio_tony]

Better stereo separation and reduced interaction between channels under heavy load are the primary reasons.

Placement close to speakers resulting in short speaker cables can also be an advantage (depending on the length of the low level cable run).

There are a few amps with dual power supplies which are effectively mono blocks as well.

 

[FrantzM]

Hi

There are some use caseS for single channel aka "monoblocks" amplifiers:
You may want to place the amplifiers close to the speakers. The sonic merits are debatable, in most home cases, I believe these to be non existent).
The ergonomics also, are debatable. You still have to bring power and signal to the "monoblocks" via longer, perhaps more expensive cables. Yes, you would use shorter speaker cables but... likely same sonic results...
...

The truth is that, on paper and in term of measurements. there are some technical reasons why a single channel amplifier could provide better performances than multiple channels in one case:
Power supply is not shared between multiple channels, so more power available at any given time to that specific channel...
Less potential crosstalk because of that..
Less distortion... maybe
Less noise ... maybe...
To sum: potentially better performance because of the above ? Better thermal management ? Maybe ...

The reason why there are monoblocs?
Marketing:
According to the American Marketing Association (AMA.. a bit of an irony that it shares acronym with the American Medical Association),

Marketing is the activity, set of institutions, and processes for creating, communicating, delivering, and exchanging offerings that have value for customers, clients, partners, and society at large.

Audio companies are commercial, for profit entities. They must make money and through marketing and their watching their markets they find ways to derive more profit. A "monoblock" pair, usually cost more than its similar performance-wise, "stereo" amp. So more money for all stakeholders...

They look cooler..
They look more ... "Audiophile"
As for the audible benefits... See above for marketing.

My $0.02

Peace.

 

[Overseas]

They look cooler and seems run cooler, so to say

 

[diablo]

I have two pairs of speakers in my lounge, one set for the TV and the others for music. They are powered by two Fosi V30 stereo units - though one does both lefts and the other the rights. So sort of quasi-monoblocks.

Does it make any difference? Probably not. I have a sub so they are both crossed at 75Hz and don't use much power.

If I wasn't using a sub then it might make a difference, maybe?

 

[Hear Here]

Good point. But having shorter speaker cables would mean having larger RCA cables, so what's the point?

I agree with the "longer interconnect, shorter speaker cable" principle, but of course the interconnect should be balanced (XLR) if the runs are long. Your amp examples are very low cost and I doubt they'd be of balanced design.

As you get higher quality kit, the advantage of mono amps increases as balanced connection is more likely to be an option and can be taken advantage of.
But to answer your question, at the level you are talking about, most of your cash goes into casework, power supply and sockets, so duplicating these appears daft if the actual amp spec between the mono and stereo versions is the same - and I don't mean just the quoted output wattage.