My year-long receiver/pre-pro experiment.

slipperybidness

slipperybidness

Audioholic Warlord
Just a note to OP the pioneer you have is a MOSFET A/B amp not class D and all receivers are not class D
Ouch! When you see a gross error like this, it makes me take the entire post with a large grain of salt.
 
slipperybidness

slipperybidness

Audioholic Warlord
I tried a ICE based D-Sonic with my Revels a few years back and something was not quite right with the bass.

- Rich
That is VERY ODD. I wonder if it was something with THAT design or THAT amp was faulty.

Typically, the problems associated with Class D amps are all associated with the high frequencies, not the low frequencies.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
That is VERY ODD. I wonder if it was something with THAT design or THAT amp was faulty.

Typically, the problems associated with Class D amps are all associated with the high frequencies, not the low frequencies.
Well, I don't know. I mean what's more demanding as far as power requirement? The tweeter and midrange require a lot less power (I heard 10%) than the bass. And the bass is where you typically see the minimum impedance dip and wide phase angles.

So if any amp (regardless of class) can't handle the load, I would say the bass would suffer.

BTW, who came up with the idea that high frequencies anomalies were associated with class-D amps?

I bet it started out with people listening to some crappy Yamaha pro cab speakers that measured 80Hz-10kHz +/-3dB and then dropped to -10dB at 12kHz. :D No wonder they associated bad treble with class D amps when it was the crappy speakers. :D
 
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RichB

RichB

Audioholic Field Marshall
That is VERY ODD. I wonder if it was something with THAT design or THAT amp was faulty.

Typically, the problems associated with Class D amps are all associated with the high frequencies, not the low frequencies.
I am not sure, the Pioneer SC-07 had linearity issues when driving 4 ohm loads (discovered by AH).
D-Sonic is not longer using ICE amp modules and their newer design is supposed to be stable into 2 ohms.

I'd like to class-D amps measured into load, multi-tone, basically beat the tar out them.

- Rich
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
I'd like to see class-D amps measured into load, multi-tone, basically beat the tar out them.
- Rich
I'm reporting you to PETA - People for the Ethical Treatment of Amps. :eek: :D
 
slipperybidness

slipperybidness

Audioholic Warlord
Well, I don't know. I mean what's more demanding as far as power requirement? The tweeter and midrange require a lot less power (I heard 10%) than the bass. And the bass is where you typically see the minimum impedance dip and wide phase angles.


BTW, who came up with the idea that high frequencies anomalies were associated with class-D amps?
You are correct that the bass does indeed require more power. So, if the amp were under-powering the speakers then that could explain the problem. BUT, that would not be a problem inherent with Class D topology but rather a problem of too little power (ie trying to drive the amp beyond its limits). Too little power can be a problem with ANY class of amp.

I'm sorry, I should be more clear and precise with high frequencies and Class D amps. Problems with the high frequency response WAS a problem at the birth of the class D topology. As far as I can tell, MODERN Class D amps have over-come those problems that the first few generations of class D amps suffered from.

So, HISTORICALLY there were problems with class D reproducing the high frequencies. Since Class D are "switching amplifiers", the "switching" needs to be orders of magnitude quicker than the highest frequency (20kHz), and it took a few generations of designs to get that figured out.

As far as Class D amps having problems reproducing bass (low frequencies), that has never been an issue associated with class D. Furthermore, class D amps are very popular in the car audio community and in the SPL competitions (driving subs).

On a side note, I'm danged interested in those new NAD Master Series that AH just announced. They are using Hypex nCore amps!
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
You are correct that the bass does indeed require more power. So, if the amp were under-powering the speakers then that could explain the problem. BUT, that would not be a problem inherent with Class D topology but rather a problem of too little power (ie trying to drive the amp beyond its limits). Too little power can be a problem with ANY class of amp.

I'm sorry, I should be more clear and precise with high frequencies and Class D amps. Problems with the high frequency response WAS a problem at the birth of the class D topology. As far as I can tell, MODERN Class D amps have over-come those problems that the first few generations of class D amps suffered from.

So, HISTORICALLY there were problems with class D reproducing the high frequencies. Since Class D are "switching amplifiers", the "switching" needs to be orders of magnitude quicker than the highest frequency (20kHz), and it took a few generations of designs to get that figured out.

As far as Class D amps having problems reproducing bass (low frequencies), that has never been an issue associated with class D. Furthermore, class D amps are very popular in the car audio community and in the SPL competitions (driving subs).

On a side note, I'm danged interested in those new NAD Master Series that AH just announced. They are using Hypex nCore amps!
Yeah, I tend to think that amps are amps. But you know....... What are you going to do? :D
 
P

PENG

Audioholic Slumlord
Well, I don't know. I mean what's more demanding as far as power requirement? The tweeter and midrange require a lot less power (I heard 10%) than the bass. And the bass is where you typically see the minimum impedance dip and wide phase angles.

So if any amp (regardless of class) can't handle the load, I would say the bass would suffer.
But aren't your Funks class D? I would hope their bass don't suffer because of that..
:D
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
But aren't your Funks class D? I would hope their bass don't suffer because of that..
:D
Oh, no, that is one reason I don't own subs with built-in amps (active subs). 100% of my subs are passive so that I can use my own class A/B amps or any amps I freely choose. ;)

Yeah, so the Funk are passive and I use my ATI AT3002 to power them, not class-D or digital amps. :D
 
crossedover

crossedover

Audioholic Chief
Oh, no, that is one reason I don't own subs with built-in amps (active subs). 100% of my subs are passive so that I can use my own class A/B amps or any amps I freely choose. ;)

Yeah, so the Funk are passive and I use my ATI AT3002 to power them, not class-D or digital amps. :D
Ah yes those under powered subs. What would 1500 watts of class ab cost:eek:
And what of the crown amps you had lol
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Ah yes those under powered subs. What would 1500 watts of class ab cost:eek:
And what of the crown amps you had lol
Yeah, I'm sure every sub uses or needs 1500 watts of power. Just like every speaker uses or needs 1000 watts of power.

I wonder why most people have their sub volume at 25% and their sub trim level at -6.0dB? Oh, wait, it's because their subs need 1500 watts of power.

They are not under-power if they don't require it. It's the same principle as speakers and power requirement.

Quality over quantity. ;)

It all depends on distance, room size, volume, driver thermal and physical limits, etc.

Let's put it this way. A single NHT 10" sub with only 80 watts of power (set to 50% volume) shakes my 18' x 20' x 12' ceiling room like an earthquake. So, no, the Funk subs do not need 1500 watts of power for my room unless I plan on demolishing my house or something.

Oh, I sold the Crown XLS 2500 amps to a church. They needed the amps more for that huge room size. It was for a good cause. :D
 
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