Singel Mosfet outputstage.

Baard · 21st May 2004, 05:58 PM

Danish - GamuT Audio, former Sirius have been producing "High-end" amplifiers for more then 2 decades. And they have always been faithful to their special topology - single Mosfet output stage.

They are using industrial Mosfets. Could I use these Mosfet in a Pass amplifier with excellent result, and instead of more IRF Mosfets in parallel?

From their web site:
http://www.gamutaudio.com/
This new technology offers two major advantages:

A smooth and detailed sound quality, which until now only was available in a few low powered class A power amplifiers.

Improved reliability, 4 parallel transistors gives 4 times higher chance of a breakdown, compared to 1 transistor.

Nelson Pass · 21st May 2004, 06:41 PM

The Gamut apparently uses a single pair of complementary
output devices. I don't happen to see the merit of their
philosophy, especially since quite a few of the "industrial"
devices consist simply of paralleled devices in a single package.

Stocker · 21st May 2004, 06:48 PM

shhhhh-

the advantage comes in on the bottom line...

djk · 23rd May 2004, 11:55 PM

Industrial 'bloc' transistors are made for switching, not linear use.

IR told me that they won't even be sure the individual die are from the same date lot, much less matching Vgs.

Semelab being lateral devices is not as bad, however, there are no individual gate stopper resistors and they may oscillate.

Nelson Pass · 24th May 2004, 05:53 PM

I bought a few of these, and as far as I can tell there
is OK internal matching, but only because the machines
that take the die from the wafer do so in a systematic pattern,
not through any effort on IR's part. This is the same phenomenon
that you see taking parts out of tubes, where you can
sequentially trace the location of the parts on a circular wafer
based on the matching and you get a sequence that vaguely
resembles the periodic table of the elements.

djk · 29th May 2004, 10:17 AM

75V 470W IRFP2907-ND $3.96

100V 580W IRFPS3810-ND $4.04

500V 460W IRFP32N50K-ND $5.04

The industrial 'block' packages go for $35~$50 each

These are TO247 and 'super' TO247 packages.

The 100V one might work well in a circlotron.

21st May 2004, 05:58 PM	#1
Baard diyAudio Member Join Date: May 2002 Location: Oslo	Singel Mosfet outputstage. Danish - GamuT Audio, former Sirius have been producing "High-end" amplifiers for more then 2 decades. And they have always been faithful to their special topology - single Mosfet output stage. They are using industrial Mosfets. Could I use these Mosfet in a Pass amplifier with excellent result, and instead of more IRF Mosfets in parallel? From their web site: http://www.gamutaudio.com/ This new technology offers two major advantages: A smooth and detailed sound quality, which until now only was available in a few low powered class A power amplifiers. Improved reliability, 4 parallel transistors gives 4 times higher chance of a breakdown, compared to 1 transistor.

21st May 2004, 06:48 PM	#3
Stocker diyAudio Member Join Date: Dec 2003 Location: Austin	shhhhh- the advantage comes in on the bottom line... __________________ Jesus loves you.

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21st May 2004, 06:41 PM	#2
Nelson Pass The one and only Join Date: Mar 2001	The Gamut apparently uses a single pair of complementary output devices. I don't happen to see the merit of their philosophy, especially since quite a few of the "industrial" devices consist simply of paralleled devices in a single package.

23rd May 2004, 11:55 PM	#4
djk diyAudio Member Join Date: Feb 2001 Location: USA	Industrial 'bloc' transistors are made for switching, not linear use. IR told me that they won't even be sure the individual die are from the same date lot, much less matching Vgs. Semelab being lateral devices is not as bad, however, there are no individual gate stopper resistors and they may oscillate.

24th May 2004, 05:53 PM	#5
Nelson Pass The one and only Join Date: Mar 2001	I bought a few of these, and as far as I can tell there is OK internal matching, but only because the machines that take the die from the wafer do so in a systematic pattern, not through any effort on IR's part. This is the same phenomenon that you see taking parts out of tubes, where you can sequentially trace the location of the parts on a circular wafer based on the matching and you get a sequence that vaguely resembles the periodic table of the elements.

29th May 2004, 10:17 AM	#6
djk diyAudio Member Join Date: Feb 2001 Location: USA	75V 470W IRFP2907-ND $3.96 100V 580W IRFPS3810-ND $4.04 500V 460W IRFP32N50K-ND $5.04 The industrial 'block' packages go for $35~$50 each These are TO247 and 'super' TO247 packages. The 100V one might work well in a circlotron.