Switched Amps. Where Could The Difference Be Coming From?

[Dimitri]

What's the rated power of the speakers ?

 

[Sokel]

Is there a possibility that you overestimated the 502?
(Luckily their datasheets don't resort to the BS 1/5 usual power ratings and they state real numbers even if they have a note about it and about sufficient cooling ,so 2x50 watt for the 252 and 2x100 watt for 502 continuous )




It doesn't take much if you're using EQ,RC,etc.

 

[Deleted member 48726]

Is there a possibility that you overestimated the 502?
(Luckily their datasheets don't resort to the BS 1/5 usual power ratings and they state real numbers even if they have a note about it and about sufficient cooling ,so 2x50 watt for the 252 and 2x100 watt for 502 continuous )


View attachment 341613View attachment 341614

It doesn't take much if you're using EQ,RC,etc.

Hmm. Is that value adhering to some standard? 100 watts continuous is also quite a lot. I mean if we are to consider their max power ratings as "dynamic power" capabilities there should be a healthy headroom for most setups even if EQ or room correction is applied.
Also we don't know what speakers OP has?

 

[Sokel]

Hmm. Is that value adhering to some standard? 100 watts continuous is also quite a lot. I mean if we are to consider their max power ratings as "dynamic power" capabilities there should be a healthy headroom for most setups even if EQ or room correction is applied.
Also we don't know what speakers OP has?

100 watt is nothing in a moderate room using EQ,RC and high dynamic content.
OP has stated that his 252 was already clipping.
In such situations the rule of thump is not twice the power,but more likely 4 times the power and up as it has to override the before clipping but also leave a small amount of headroom.

That without considering speaker's limits.

 

[Deleted member 48726]

100 watt is nothing in a moderate room using EQ,RC and high dynamic content.
OP has stated that his 252 was already clipping.
In such situations the rule of thump is not twice the power,but more likely 4 times the power and up as it has to override the before clipping but also leave a small amount of headroom.

That without considering speaker's limits.

I know and I follow that rule as well. Plus some!
But, if the 502 has a rating of 100 W continuously and is capable of supplying dynamically 350 to 500 W max ( 1% THD) That should be a reasonable headroom for music.

But given the information from OP it is probably not enough of an upgrade.

For reference-->

Buckeye Nc502mp Review (6 Channel Amplifer)

This is a review and detailed measurements of the Buckeye Hypex NC502MP based, 6-channel amplifier. It was kindly purchased and drop shipped to me by our dear moderator, @AdamG247. I don't know what it costs. Not sure what there is to say about the case: Or the back panel: Other than...

www.audiosciencereview.com

EDIT:
Here is a dual channel NC502MP (Though measured with one channel driven)-->

Hypex NC502MP Power Sweeps and Distortion Measurements

Hypex NC502MP Power Sweeps and Distortion Measurements

analog-precision.com

 

[SIY]

If OP produces comprehensive electrical measurements I will buy you a drink SIY.

They don't even have to be comprehensive. Just a simple measurement using music that he thinks shows the effect (equipment needed: soundcard/interface and four resistors) and waveform comparison using @pkane 's incredible software. If there's clipping or overload or whatever from the amp, the differences will be trivially easy to see.

 

[antcollinet]

Is there a possibility that you overestimated the 502?
(Luckily their datasheets don't resort to the BS 1/5 usual power ratings and they state real numbers even if they have a note about it and about sufficient cooling ,so 2x50 watt for the 252 and 2x100 watt for 502 continuous )


View attachment 341613View attachment 341614

It doesn't take much if you're using EQ,RC,etc.

But the short term 250 or 500W power can last a long time - as stated based on cooling. One assembler said they tested for something like 10 minutes and it didn't limit. So as long as you don't need more than the continuous rating for average listening level, you don't need to worry about peak limiting.

 

[Sokel]

I know and I follow that rule as well. Plus some!
But, if the 502 has a rating of 100 W continuously and is capable of supplying dynamically 350 to 500 W max ( 1% THD) That should be a reasonable headroom for music.

But given the information from OP it is probably not enough of an upgrade.

For reference-->

Buckeye Nc502mp Review (6 Channel Amplifer)

This is a review and detailed measurements of the Buckeye Hypex NC502MP based, 6-channel amplifier. It was kindly purchased and drop shipped to me by our dear moderator, @AdamG247. I don't know what it costs. Not sure what there is to say about the case: Or the back panel: Other than...

www.audiosciencereview.com

View attachment 341624

I saw the numbers as well but I also saw a reference to Audiolense and such.If by any chance he DSPs not only by cutting peaks but also filling dips,well...
The momentary 1% power doesn't tell me much,I prefer the knee measurement every time which in your example is a bit abnormal too (rapid rise in distortion after the 10 watts with 2 channels driven,was that the one with the ferromagnetic connection? )

 

[Deleted member 48726]

I saw the numbers as well but I also saw a reference to Audiolense and such.If by any chance he DSPs not only by cutting peaks but also filling dips,well...
The momentary 1% power doesn't tell me much,I prefer the knee measurement every time which in your example is a bit abnormal too (rapid rise in distortion after the 10 watts with 2 channels driven,was that the one with the ferromagnetic connection? )

I agree. But surely there should be enough power!? Further investigation can continue when we know the OP's speakers and EQ details. Somethings missing for sure.

For reference I just updated my post to include a dual channel NC502MP as well.

 

[Sokel]

But the short term 250 or 500W power can last a long time - as stated based on cooling. One assembler said they tested for something like 10 minutes and it didn't limit. So as long as you don't need more than the continuous rating for average listening level, you don't need to worry about peak limiting.

Yes,but look at the conditions:



Even mounted on a 100mm heatshink,etc or active cooled the rating is at 1Khz.
I wonder if that fix that goes around lately with the added capacitance if used for lows has to do with the complains about these amps clipping by the time they shouldn't .

The given is that the previous one was already clipping.

 

[Deleted member 48726]

Yes,but look at the conditions:

View attachment 341627

Even mounted on a 100mm heatshink,etc or active cooled the rating is at 1Khz.
I wonder if that fix that goes around lately with the added capacitance if used for lows has to do with the complains about these amps clipping by the time they shouldn't .

The given is that the previous one was already clipping.

I notice the load resistor addendum as well..

 

[Deleted member 21114]

Are we skipping the foreplay of determining if a problem actually exists and jumping straight to the heavy petting of spec sheets and graphs?

 

[Sokel]

Are we skipping the foreplay of determining if a problem actually exists and jumping straight to the heavy petting of spec sheets and graphs?

Last time I checked we're at ASR,charts and data are not banned.

 

[Deleted member 48726]

Are we skipping the foreplay of determining if a problem actually exists and jumping straight to the heavy petting of spec sheets and graphs?

What else is there to do? -We are missing information from the OP. Now it seems we already have a sound collection of data to refer to when OP hopefully returns with more information.

 

[Sokel]

What else is there to do? -We are missing information from the OP. Now it seems we already have a sound collection of data to refer to when OP hopefully returns with more information.

Yep,and lets not forget that doubling the power results in a 3db SPL rise,not much if in the previous condition was already clipping.

(I have to ask,how does the clipping was evident?Does the NC252 MP built has an indicator? )

 

[boxerfan88]

Are we skipping the foreplay of determining if a problem actually exists and jumping straight to the heavy petting of spec sheets and graphs?

This post really had me in stitches

 

[Deleted member 48726]

Yep,and lets not forget that doubling the power results in a 3db SPL rise,not much if in the previous condition was already clipping.

(I have to ask,how does the clipping was evident?Does the NC252 MP built has an indicator? )

Yeah. An alternative explanation could just as well be that the line level signal output or input is clipping.

 

[Sir Sanders Zingmore]

Maybe a silly question but it needs to be asked, are you sure you didn't connect the speakers out of phase?

 

[Speedskater]

You can set A/B test levels with any Digital Multi-Meter (DMM) that has a low voltage AC range. It doesn't need to be accurate or True RMS.
Just use a test track that has a mid-frequency tone (400 Hz - 2kHz) or pink noise and measure at the loud speaker terminals.

 

[Trdat]

Bookshelf-3WC

www.troelsgravesen.dk