High Bandwidth Amplifiers

[FrantzM]

Hi

Little known outside Italy .. Wide bandwidth too

http://www.normaudio.com/normaudio/en/prodotti/revo-ipa-140/

1.8 MHz -3 dB !!!!

 

[amirm]

Thanks...why do they design for 350khz if its higher than need be?

It is an engineering challenge (so engineers like to brag about it when they accomplish it) and a marketing figure of merit.

What comes before the amp and after it severely limit bandwidth. Here is a sample spectrum from a Reference Recording Highres file I generated for another topic on ASR Forum today:

No usable information above 30 Khz.

With SACD/DSD it is actually a demerit to have such high bandwidth as it uses noise shaping to push garbage (quantization noise) above hearing range:

Pushing that ultrasonic noise into speakers is likely not a wise thing to do especially since you can't hear how loud it might be.

It is a figure I personally ignore.

 

[Elberoth]

I think you mean Mega hertz (MHz). I don't know of any audio amps that go into the GHz range.

Sorry, a typo. Amps barely reach a few MHz ... not to mention 1GHz (1000MHz)

 

[LL21]

Thanks for taking the time. As an RBCD player, all set for me in any event!

It is an engineering challenge (so engineers like to brag about it when they accomplish it) and a marketing figure of merit.

What comes before the amp and after it severely limit bandwidth. Here is a sample spectrum from a Reference Recording Highres file I generated for another topic on ASR Forum today:

No usable information above 30 Khz.

With SACD/DSD it is actually a demerit to have such high bandwidth as it uses noise shaping to push garbage (quantization noise) above hearing range:

Pushing that ultrasonic noise into speakers is likely not a wise thing to do especially since you can't hear how loud it might be.

It is a figure I personally ignore.

 

[Hyperion]

Hi

Little known outside Italy .. Wide bandwidth too

http://www.normaudio.com/normaudio/en/prodotti/revo-ipa-140/

1.8 MHz -3 dB !!!!

Norma makes fantastic - and more affordable than most on this level - amplifiers that really deserves more attention.

/ Marcus

 

[Elberoth]

Pushing that ultrasonic noise into speakers is likely not a wise thing to do especially since you can't hear how loud it might be.

Wide banwidth designs have nothing to do with the bandwith of the source material you are gonna use !

You have missed the whole point of those designs.

 

[JackD201]

The Levinson 53 can likewise be considered a wide bandwidth amplifier as the output devices are also rapid switchers in step with the 2Mhz power supply albeit the output is filtered if I'm not mistaken at around 100kHz.

 

[amirm]

Wide banwidth designs have nothing to do with the bandwith of the source material you are gonna use !

Yeh, I got confused thinking the amplifier amplifies what is fed to it.

You have missed the whole point of those designs.

Which is what?

 

[audio.bill]

Yeh, I got confused thinking the amplifier amplifies what is fed to it.

Which is what?

The engineering theory behind wide bandwidth designs is most commonly that for an amplifier to maintain proper phase response within the audible frequency range requires it to have a frequency bandwidth well beyond the range of human hearing. I'm not going to engage in any arguments about the validity of such a theory or the required bandwidth required to achieve proper phase response, but am just trying to address your question about the reason for such designs. Hope this helps!

 

[LarsS]

Norma makes fantastic - and more affordable than most on this level - amplifiers that really deserves more attention.

/ Marcus

As owner of a Norma Revo IPA-140 couldn't agree more. It's a properly engineered product, not sure its qualities is directly related to its wide bandwidth.

 

[gryphongryph]

Lars, can I ask what speakers you use with your amp?
Have been thinking about this amp to use with my Graham Audio LS 5/9.