Korean compared to Brazilian amplifiers (Electrical theory stuff)

[SounDrive Pro Seller]

I have o-scoped plenty of brazilian and korean amps... not a huge difference in waveforms. Never seen a waveform like that from the 3 Taramp's I scoped.

 

[ciaonzo 5,000+ posts]

Nominal Impedance directly affects how the load reacts to power input considering a subwoofer and amp are a highly complicated, coupled electromagnetic circuit. It's only one of several variables that play a role, but it is there. Inductors by themselves get mathematically hairy real quick even without throwing in a non-constant BL curve, heat dissipation/buildup, the amps internals, etc....You can't just say P=I*V*cos(phi) or I=V/Z and expect that to be able to describe the situation fully, especially considering you're basically ignoring the time dependence of each EM entity. This is a dynamic situation where I believe your experience/knowledge in approximately steady state/well defined systems leads you to oversimplify what's going on.
The best answer IMO is it depends on way too many variables for anyone to be able to say definitively what's best for any person's setup.

I do agree; there are tons of other areas that need to be optimized first before anyone get their panties in a wad about brazilian vs korean. To be honest I thought the biggest issue about brazilian vs korean was the fact many people claim bad QC/reliability or inconsistent throughput across their frequency response which has more to do with topology. As far as power at higher voltages I don't think I've ever heard anyone complain about non brazilian offerings at higher impedances.:yumyum:JBL Crown

Nicely put, I concur.

 

[SounDrive Pro Seller]

Square wave on the HD "10k" //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

I was being facetious, and no it was clean power. I played a frequency was lower than I should have at full tilt and smoked the coils due to low impedance under tuning.

Given my voltage, I'm estimating 3-4k or more per sub, clamped. Well over what any 3" 4 layer coil is capable of taking for more than a few seconds.

 

[wew lad 5,000+ posts]

i dont really understand it but ive definitely seen it first hand, agreed that it's inconsequential in the whole scheme of things. however, ill specifically note that the waveform doesnt cleanly transition to a clipped sine wave like what i see with korean boards, just a weird fuzzy transition to a square

 

[ciaonzo 5,000+ posts]

I was being facetious, and no it was clean power. I played a frequency was lower than I should have at full tilt and smoked the coils due to low impedance under tuning.
Given my voltage, I'm estimating 3-4k or more per sub, clamped. Well over what any 3" 4 layer coil is capable of taking for more than a few seconds.

Datsalottapowa

i dont really understand it but ive definitely seen it first hand, agreed that it's inconsequential in the whole scheme of things. however, ill specifically note that the waveform doesnt cleanly transition to a clipped sine wave like what i see with korean boards, just a weird fuzzy transition to a square

I wonder if it's the amplifier generating that noise, maybe something with the mulitple rails switching on and off for the sake of efficiency. Similar to the crossover distortion found between fets in the output stage? I'm banking on you knowing what that is.

 

[adulbrich 5,000+ posts]

I was being facetious, and no it was clean power. I played a frequency was lower than I should have at full tilt and smoked the coils due to low impedance under tuning.
Given my voltage, I'm estimating 3-4k or more per sub, clamped. Well over what any 3" 4 layer coil is capable of taking for more than a few seconds.

Gotcha

i dont really understand it but ive definitely seen it first hand, agreed that it's inconsequential in the whole scheme of things. however, ill specifically note that the waveform doesnt cleanly transition to a clipped sine wave like what i see with korean boards, just a weird fuzzy transition to a square

Still ends up as a square. That's a soft clip that you posted a pic of iirc

 

[adulbrich 5,000+ posts]

I was being facetious, and no it was clean power. I played a frequency was lower than I should have at full tilt and smoked the coils due to low impedance under tuning.
Given my voltage, I'm estimating 3-4k or more per sub, clamped. Well over what any 3" 4 layer coil is capable of taking for more than a few seconds.

Gotcha

i dont really understand it but ive definitely seen it first hand, agreed that it's inconsequential in the whole scheme of things. however, ill specifically note that the waveform doesnt cleanly transition to a clipped sine wave like what i see with korean boards, just a weird fuzzy transition to a square

Still ends up as a square. That's a soft clip that you posted a pic of iirc

 

[SounDrive Pro Seller]

Datsalottapowa
I wonder if it's the amplifier generating that noise, maybe something with the mulitple rails switching on and off for the sake of efficiency. Similar to the crossover distortion found between fets in the output stage? I'm banking on you knowing what that is.

I'm going to guess that those noises were caused by EMI, similar to why sometimes the termlab magnum won't accurately read power. None of the amps I have tested thus far had this issue though. I wonder if it's only the older amps

 

[SounDrive Pro Seller]

Datsalottapowa
I wonder if it's the amplifier generating that noise, maybe something with the mulitple rails switching on and off for the sake of efficiency. Similar to the crossover distortion found between fets in the output stage? I'm banking on you knowing what that is.

I'm going to guess that those noises were caused by EMI, similar to why sometimes the termlab magnum won't accurately read power. None of the amps I have tested thus far had this issue though. I wonder if it's only the older amps

 

[ciaonzo 5,000+ posts]

I'm going to guess that those noises were caused by EMI, similar to why sometimes the termlab magnum won't accurately read power. None of the amps I have tested thus far had this issue though. I wonder if it's only the older amps

Yes, that makes good sense. I should have come to the same conclusion since I see it on ECG machines all the time.
Yeah, that's a solid usable output in that photo.

 

[SounDrive Pro Seller]

I'll have the HD10k back in my possession soon and I'll be doing pretty extensive comparison between it at 2 ohm and the 6500 wired to .5. I may even get a voice coil temp sensor to check how impedance affects thermal power handling given the same clamped power.

 

[Papermaker85 5,000+ posts]

I'm going to guess that those noises were caused by EMI, similar to why sometimes the termlab magnum won't accurately read power. None of the amps I have tested thus far had this issue though. I wonder if it's only the older amps

looks like some noise to me

 

---------- Post added at 08:19 PM ---------- Previous post was at 08:18 PM ----------

 

I'll have the HD10k back in my possession soon and I'll be doing pretty extensive comparison between it at 2 ohm and the 6500 wired to .5. I may even get a voice coil temp sensor to check how impedance affects thermal power handling given the same clamped power.

ill let ya do that for yourself. im sure you will agree with me

 

[Papermaker85 5,000+ posts]

Handheld Infrared Pyrometer

they have very high accuracy tempature elements but the coil is moving so its almost impossible to test.Handheld Infrared Pyrometer

if your strapped for cash these are actually decent enoughhttps://www.google.com/search?q=extech+clamp+meter&client=ms-android-att-us&sa=X&biw=412&bih=651&tbs=vw:l&tbm=shop&prmd=sivn&srpd=13882535069046214651&prds=epd:360424594591976696,paur:ClkAsKraX54c95JKJUAdYy8lNWoNQ7qLPXhdMCX6K9u47SQAjmYvYho2uWMHgh130AdLV4FbXlnxc4WrT9CjBcBmf5hPuK6vyDDB2PGvXzc7JvYOG1iRr7CClBIZAFPVH705NwdwxlRzy8tH7DRRNMwOnc1POA,cdl:1,cid:16694441871785956771&ved=0ahUKEwimuuTx4enLAhXEmoMKHbebCNsQgTYIhwMwDQ&ei=NHz8VqbQIsS1jgS3t6LYDQ

 

[Papermaker85 5,000+ posts]

Handheld Infrared Pyrometer

they have very high accuracy tempature elements but the coil is moving so its almost impossible to test.Handheld Infrared Pyrometer

if your strapped for cash these are actually decent enoughhttps://www.google.com/search?q=extech+clamp+meter&client=ms-android-att-us&sa=X&biw=412&bih=651&tbs=vw:l&tbm=shop&prmd=sivn&srpd=13882535069046214651&prds=epd:360424594591976696,paur:ClkAsKraX54c95JKJUAdYy8lNWoNQ7qLPXhdMCX6K9u47SQAjmYvYho2uWMHgh130AdLV4FbXlnxc4WrT9CjBcBmf5hPuK6vyDDB2PGvXzc7JvYOG1iRr7CClBIZAFPVH705NwdwxlRzy8tH7DRRNMwOnc1POA,cdl:1,cid:16694441871785956771&ved=0ahUKEwimuuTx4enLAhXEmoMKHbebCNsQgTYIhwMwDQ&ei=NHz8VqbQIsS1jgS3t6LYDQ

 

[wew lad 5,000+ posts]

Still ends up as a square. That's a soft clip that you posted a pic of iirc

a fuzzy square, sometimes with spikes at the beginning of the square and dips at the end of it. the amplifier is clearly being driven beyond its capability and thats really the point here