Apollon Hypex NC2K Monoblock Amplifier Review

[tomtoo]

I use the Earth itself as a subwoofer. Several volcanoes in the Pacific rim function as "ports!"

You can track when I'm watching a movie here:
https://earthquake.usgs.gov/earthquakes/map/?extent=12.85465,-136.14258&extent=57.32652,-53.83301

I love the sound!

 

[jomark911]

Yes but we talk about average, and 94db for a hifi speaker is a lot. There is a user in here with some nice big Horns that are specified at 109db, but hell thats not average.

Yes , my 1990"s JBL TLX 20"s were 93db's.
My wife's Focal utopia , same era were 92db"s .
My brother's in law focal's were 92,5db's , same era. The one with two 8" woofers .
This is far from 109db"s horns are pushing out.
My JBL's XPL 200 were 92db"s if memory serves.
My cousin"s JBL K2S 9800 are 92db . If memory serves .
My CORAL'S DX ELEVEN are 90db's , and my CORAL'S DXseven are 93db.s normal 97db"s max.
I can continue , but there"s no point.

 

[tomtoo]

Yes , my 1990"s JBL TLX 20"s were 93db's.
My wife's Focal utopia , same era were 92db"s .
My brother's in law focal's were 92,5db's , same era. The one with two 8" woofers .
This is far from 109db"s horns are pushing out.
My JBL's XPL 200 were 92db"s if memory serves.
My cousin"s JBL K2S 9800 are 92db . If memory serves .
My CORAL'S DX ELEVEN are 90db's , and my CORAL'S DXseven are 93db.s normal 97db"s max.
I can continue , but there"s no point.

Measured or manufacturer specification? But who cares? A average is a average. And i would say the average for a hifi floorstander is less than 90db. For a bookschelf less than 87db.

 

[jomark911]

Care to explain then what you meant by “normal” and “most”?

Check Stereophile’s average, which is derived from the thousands of speakers they’ve measured over the decades. 86.3dB/2.83V/1m, IIRC.

There's little to explain. Of course.
Normal is normal as normal , ie something that appears quite often . Most is something that appears more frequently than normal.
If you search, some new speakers specs , they state 90db anechoic 93db average room.
I don't rely on Stereophile"s measurements , since there isn't a term as average sensitivity in my vocabulary. As there isn't an analogue term in power amplifier"s power.
Average , I'm sure you know is a function of mathematics , just to compare some values that can not be compared otherwise.
Or anyway , a method of taking a mid point reference , for no reason.

 

[jomark911]

Measured or manufacturer specification? But who cares? A average is a average. And i would say the average for a hifi floorstander is less than 90db. For a bookschelf less than 87db.

Have you ever auditioned a cerwin vega ? their sensitivity is quite more than 92 db"s.
Not to mention some older infinity speakers.
What has gotten you with the average? Why do we have to average anything? Specially speaker's sensitivity's?

 

[audioBliss]

I wonder how many watts I'm using for my main speakers at typical listening levels? I have my speakers crossed over at 90Hz to multiple subwoofers. I wonder how many watts are being used in this scenario where the heavy lifting is being done by the subwoofers which run off a PA amp with very many watts peak power.

I'm thinking that the need for high power amps should be less in this scenario but I do get a bit curious how it would sound with even more watts to my main speakers. I've never heard my nc400 monoblocks clip though. I have 92dB efficient speakers(4Ohm nominal) at 4meter distance. I guess one would need a measurement of the speaker to know for sure.

Now as in the video the source material does play a major role here how loud the volume get's turned up..

 

[tomtoo]

Have you ever auditioned a cerwin vega ? their sensitivity is quite more than 92 db"s.
Not to mention some older infinity speakers.
What has gotten you with the average? Why do we have to average anything? Specially speaker's sensitivity's?

Couse when we talk about average we talk about average and not about high or low level exceptions.

 

[jomark911]

I wonder how many watts I'm using for my main speakers at typical listening levels? I have my speakers crossed over at 90Hz to multiple subwoofers. I wonder how many watts are being used in this scenario where the heavy lifting is being done by the subwoofers which run off a PA amp with very many watts peak power.

I'm thinking that the need for high power amps should be less in this scenario but I do get a bit curious how it would sound with even more watts to my main speakers. I've never heard my nc400 monoblocks clip though. I have 92dB efficient speakers(4Ohm nominal) at 4meter distance. I guess one would need a measurement of the speaker to know for sure.

Now as in the video the source material does play a major role here how loud the volume get's turned up..

Your speakers are rated at 4ohms , 92db. Hence their sensitivity is 92 -3=89db , because sensitivity is measured at xohms at 1 meter at 1watt.
1watt at 8 ohms is 2,83vrms. BUT the same at 4ohms is 2,83X2=5,66vrms.
So your speaker is 89db;s.

 

[audioBliss]

Your speakers are rated at 4ohms , 92db. Hence their sensitivity is 92 -3=89db , because sensitivity is measured at xohms at 1 meter at 1watt.
1watt at 8 ohms is 2,83vrms. BUT the same at 4ohms is 2,83X2=5,66vrms.
So your speaker is 89db;s.

Hmm so maybe I would then benefit from a bigger amp during at least this scenario

 

[jomark911]

Couse when we talk about average we talk about average and not about high or low level exceptions.

Ok ok.
I see your point , but it's not the AVERAGE. There is no average . My friends horns are 105db, shall we put this in the equation?
Klipsch are also very sensitive , shall we put them in?
JBL's are also very sensitive , what about those?
K2 are 92 db , if memory serves.

 

[audioBliss]

The thing with sensitivity though is that this varies with frequency right? So whatever number you have that will probably not be enough information to know for sure.

 

[jomark911]

Hmm so maybe I would then benefit from a bigger amp during at least this scenario
View attachment 88725

If you are seated at 4 meters you loose quite of the part of the music signal . Yes the calculator uses some std"s , were does the 20db headroom come from?
Do you have some KW"s of power?

 

[CDMC]

How long until someone asks if there is a way to bridge two of these into a 1 ohm load?

 

[audioBliss]

If you are seated at 4 meters you loose quite of the part of the music signal . Yes the calculator uses some std"s , were the 20db headroom comes from?
Do you have some KW"s of power?

I put those numbers in myself- 20dB seemed reasonable. Like I said I have the nc400 monoblocks. According to the calculator I needed about 700W of power. Why would I need KW's of power?

 

[tomtoo]

Ok ok.
I see your point , but it's not the AVERAGE. There is no average . My friends horns are 105db, shall we put this in the equation?
Klipsch are also very sensitive , shall we put them in?
JBL's are also very sensitive , what about those?
K2 are 92 db , if memory serves.

Man sry but i think you have a problem to understand the AVERAGE! And sure there is a average.

 

[jomark911]

@ audiobliss Because you used a 20db headroom . That's why. Do you know what is a 20db headroom ? that is about of 6 times the power you have available.
That is why I asked.

 

[jomark911]

Man sry but i think you have a problem to understand the AVERAGE! And sure there is a average.

Ok this is it I f you think like it.

 

[wwenze]

Well actually there is not a cooling system at all.
At least one that I can see.
To the right side where the power board is.
On the left where the psu is , there is this vertical thing like a aluminum bar that probably works as what? that could be a heat sink.

That thing is part of the PSU
https://www.hypex.nl/product/smps3ka700/13
The vertical section of the plate itself will do, like, 5W, max, with forced air.

It's main job is to thermally connect the switching transistors to a bigger heatsink, which is usually the chassis.

I wouldn't consider myself corrected at this point, considering this passive case failed to cool a <100W CPU properly
https://www.kitguru.net/components/cases/dominic-moass/streacom-db4-fanless-case-review/2/

And this couldn't handle things at 30W:
https://nucblog.net/2020/07/akasa-turing-fx-review-frost-canyon-fanless-case/

This handles 65W, supposedly
http://turemetal.com/product-detail-UP3.html

So I remain skeptical that a 33cm by 35cm unfinned chassis can do close to 200W. But this is where my attention span ends so I won't be concerned until somebody actually tries 2000W on this. If anything that wire is more of a concern, but that one is Hypex design apparently anyway.

 

[Jake71]

Yes , my 1990"s JBL TLX 20"s were 93db's.
My wife's Focal utopia , same era were 92db"s .
My brother's in law focal's were 92,5db's , same era. The one with two 8" woofers .
This is far from 109db"s horns are pushing out.
My JBL's XPL 200 were 92db"s if memory serves.
My cousin"s JBL K2S 9800 are 92db . If memory serves .
My CORAL'S DX ELEVEN are 90db's , and my CORAL'S DXseven are 93db.s normal 97db"s max.
I can continue , but there"s no point.

Let's see some actual measurements of these speakers, most manufacturers wildly exaggerate the efficiency of their speakers, just look at Klipch, they are off by as much as 10dB, that is directly lying to the consumers, surely their own engineers knows this is wrong, but marketing needs this lie to sell more speakers. Other more high end brands wildly exaggerating their efficiency and lying to their customers are Volti Audio and DeVore.

 

[dinglehoser]

Isn't the rise in THD and the early roll-off caused by the Sparkos SS2590 input buffers?

This comment reminds me, I need to get my Nord NC500 back to Amir for a retest now that it's fronted by Neurochrome input buffers. In its original form (with the original Hypex eval input buffers), it was the DUT for his original NC500 test; its as-tested mid-power linearity didn't match Hypex specifications, and we conjectured the eval hardware had something to do with it. (Worth noting that Putzeys himself recommended against using the eval buffers for anything other than evaluation, but I digress ...)