mosfet audio quality

How does this IRF530-based circuit compare with, say, an LM3886?

http://www.irf.com/technical-info/appnotes/an-948.pdf

I thought this would make a good first project, but if it doesn't
sound so great, then why bother...?

Anyone have experience with this circuit?

Thanks,

Michael

 

[Eeyore]

mrdarrett@gmail.com wrote:

How does this IRF530-based circuit compare with, say, an LM3886?

http://www.irf.com/technical-info/appnotes/an-948.pdf

I thought this would make a good first project, but if it doesn't
sound so great, then why bother...?

Anyone have experience with this circuit?

I have extensive experience with audio mosfets including a design that
was capable of 0.0008% THD @ 1 kHz @ 350W (almost the limit of AP test
equipment). The unit's final THD was actually limited by some op-amp
stages, although more modern op-amps would fix that.

The IR circuit is in comparison complete rubbish and very basic,
although it teaches the basic fundamentals.

Isn't the LM3886 one of National's 'Overture' ? series used in the
'gainclone' type kits ? It's very well regarded. I know someone who just
built one and has nothing but praise for it.

Graham

 

On Jul 10, 5:08 am, Eeyore <rabbitsfriendsandrelati...@hotmail.com>
wrote:

mrdarr...@gmail.com wrote:
How does this IRF530-based circuit compare with, say, an LM3886?

http://www.irf.com/technical-info/appnotes/an-948.pdf

I thought this would make a good first project, but if it doesn't
sound so great, then why bother...?

Anyone have experience with this circuit?

I have extensive experience with audio mosfets including a design that
was capable of 0.0008% THD @ 1 kHz @ 350W (almost the limit of AP test
equipment). The unit's final THD was actually limited by some op-amp
stages, although more modern op-amps would fix that.

The IR circuit is in comparison complete rubbish and very basic,
although it teaches the basic fundamentals.

Ouch.

Isn't the LM3886 one of National's 'Overture' ? series used in the
'gainclone' type kits ? It's very well regarded. I know someone who just
built one and has nothing but praise for it.

Graham

Sounds good. I read bits and pieces of Slone's book online
(books.google), and requested a similar book from the library (it
should be arriving soon, from a different library branch).

Thanks,

Michael

 

[Eeyore]

mrdarrett@gmail.com wrote:

Eeyore wrote:
mrdarr...@gmail.com wrote:
How does this IRF530-based circuit compare with, say, an LM3886?

http://www.irf.com/technical-info/appnotes/an-948.pdf

I thought this would make a good first project, but if it doesn't
sound so great, then why bother...?

Anyone have experience with this circuit?

I have extensive experience with audio mosfets including a design that
was capable of 0.0008% THD @ 1 kHz @ 350W (almost the limit of AP test
equipment). The unit's final THD was actually limited by some op-amp
stages, although more modern op-amps would fix that.

The IR circuit is in comparison complete rubbish and very basic,
although it teaches the basic fundamentals.

Ouch.

Well it's little worse that Hitachi's early app notes ! Except that Hitachi
gave vastly more support info.

Isn't the LM3886 one of National's 'Overture' ? series used in the
'gainclone' type kits ? It's very well regarded. I know someone who just
built one and has nothing but praise for it.


Sounds good. I read bits and pieces of Slone's book online
(books.google), and requested a similar book from the library (it
should be arriving soon, from a different library branch).

Google 'gainclone' but ignore all the audiophool voodoo shit. Concentrate on
the engineering aspects of it, They're basically decent IC amplifiers.

The Nat Semi data is free online of course.

Graham