Differential Pairs

[Piersma]

In the recent past i have used MAT02/03 (Analog Devices) diffential pairs for the input stage. They exibit good features except for the Vce. (40V) These transistors are closely matched and have a good long term stability. I found out that these pairs sound excellent in comparison with other pairs i have used.

I have also seen Zetex components in other commercially audio equipment for instance the Quad amplifier. In most cases the sound of this equipment is pretty nice.

Regards
Piersma

 

[Piersma]

Closed

This posting was intended as a reply on the threat that EchoWars started namely : Input Differential Pairs and Zetex transistors.

I am really sorry for the mistake.

Piersma

 

[peranders]

If you need higher voltage, just use a cascode with plain transistors. Rather easy.

Note also that these MAT have rather high caps and "low" fT, not so fast but I gather that's not a big problem for you.

 

[Piersma]

FT ?

Per,

Of course you can cascode the diff pair for higher voltages, you are right about that.
I am a little confused about the "low" transision frequency, the FT of the MAT types is minimal 190 Mhz. The output capacity for the MAT02 is 23pF. FT for the ZTX1056A is 120 Mhz.

Regards
Piersma

 

[Terry Demol]

If you need higher voltage, just use a cascode with plain transistors. Rather easy.

Note also that these MAT have rather high caps and "low" fT, not so fast but I gather that's not a big problem for you.

Depends where you run them. MAT02 has ft >300MHz
if run with a decent current.

T