Wanted [Found: MAT02]

[TwentyTrees]

No longer looking!


Hi all,

As per subject, I'm looking to buy a pair of unused MAT02 transistors. A pair of MAT12 would do in a pinch, though I'd prefer not to mix and match (ie one of each). I'm based in the UK. Please send me a PM if you have any you're prepared to part with!

Thanks,
Andy

 

[Gustav]

I checked my local, danish supplier, and they had nothing.
Banzai in Germany has both, buit they charge an arm and a leg..

https://www.banzaimusic.com/MAT02FH.html
Search the forum? Replacements were tried and discussed for the SSL9K I am sure.

 

[TwentyTrees]

Thanks Gustav, that's a really helpful lead. I'd prefer to use MAT rather than an alternative if possible, as I'll be building something to match another unit that uses MAT02, but it's definitely worth keeping alternatives in mind (particularly at those prices!).

Cheers.

 

[Rob Flinn]

I understand that you want to use a MAT 01/12, but I have used this as a sub and it worked really well. I couldn't hear a difference compared to a 9k using the MAT02.

https://www.ebay.co.uk/itm/332830887373
I originally bought a MAT02 from a supplier in Manchester, but it looked very fake, & when I tested it the Hfe was only about 60. Strangely the supplier was annoyed at having to refund me, & had blocked me from being able to buy bits from him.... I think it's quite difficult to find real MAT02 nowadays.

 

[TwentyTrees]

Thanks Rob, that's a helpful datapoint. If you and Gustav are both telling me to look at alternatives, I guess that's the way to go!

Really appreciate the advice.

 

[scott2000]

Wayne has some og 394s on his site

 

[Whoops]

Hi all,

As per subject, I'm looking to buy a pair of unused MAT02 transistors. A pair of MAT12 would do in a pinch, though I'd prefer not to mix and match (ie one of each). I'm based in the UK. Please send me a PM if you have any you're prepared to part with!

Thanks,
Andy

Like others have said, the MAT02 is unfortunately long obsolete and unavailable.
Also the LM394

It's a bit risky to buy on the web, because you can get some fake ones, I've got some fake ones some years ago. So always be careful when you see MAT02 for sale.

If the MAT12 is a dual, low noise, super-matched transistor pair, and it's readily available then go for that one. I don't know the other alternatives that exist at the moment.

Another solution that I've done that works great is to buy a pack of 30 or 40 units of BC550C transistors, measure all of them and match HFE (curve tracing with Peak DCA is even better), when you get pairs that match very very closely then you use those 2 and glue them together. You can eve put some metal or aluminum/copper foil around them.
BC550C is low noise like the MAT02
The measuring and selection makes them matched
And having them glued and foil around them will make them always at the same temperature level.
You then have your own DIY MAT02

Good Luck mate

 

[Rob Flinn]

Maybe this is another option although it seems only available in SMD form https://www.mouser.co.uk/new/analog-devices/adi-ssm2212-transistor/

 

[KA-Electonics.com]

Another solution that I've done that works great is to buy a pack of 30 or 40 units od BC550C transistor, measure all of them and match HFE (curve tracing with Peak DCA is even better), when you get pairs that match very very closely then you use those 2 and glue them together. You can eve put some metal or aluminum/copper foil around them.
BC550C is low noise like the MAT02
The measuring and selection makes them matched
And having them glued and foil around them will make them always at the same temperature level.
You then have your own DIY MAT02

Good Luck mate

Not a solution for the MAT-02 but continuing the DIY dual transistor theme....

ZTX851 matched pairs glued into an acorn "cap" nut:

I match them using a chopper circuit which compares paired devices to create an AC waveform of the delta-Vbe. It makes spotting trends easier than reading a bobbling DVM. Transistor Vbe Matching Using A Commutating Chopper-Based Circuit - Pro Audio Design Forum

The nut lowers thermal drift which measures like 1/f noise. This post shows a quieter servo response with the added mass of a nut: Flat Balanced Input Moving Coil Phono Preamp Construction Information - Page 6 - Pro Audio Design Forum

I use aluminum cap nuts now which are a little harder to find.

 

[Whoops]

Not a solution for the MAT-02 but continuing the DIY dual transistor theme....

Why can’t it be applied to the MAT-02?
There’s other specific technical details that I’m missing?

I remember a thread with people showing doing this to replace MAT-02 and LM394, unfortunately I’m not finding it at the moment

ZTX851 matched pairs glued
The nut lowers thermal drift which measures like 1/f noise.
I use aluminum cap nuts now which are a little harder to find.

Great idea, looks pretty cool
Thank you so much for sharing

 

[KA-Electonics.com]

Why can’t it be applied to the MAT-02?
There’s other specific technical details that I’m missing?
I remember a thread with people showing doing this to replace MAT-02 and LM394, unfortunately I’m not finding it at the moment
Great idea, looks pretty cool
Thank you so much for sharing

You could. It would require something like a ZTX1053 to get the gain. The 50 µV match might be a little harder.
The ZTX851 Hfe usually runs 140-200 - the ZTX1053 is more in the range of the MAT-02.

With the ZTX851 I've been able to match 100 - 250 µV pretty easily. 50 µV might require going through a lot of devices.
1 mV matching of the '851 has better than an 80% yield.

 

[TwentyTrees]

Not a solution for the MAT-02 but continuing the DIY dual transistor theme....

ZTX851 matched pairs glued into an acorn "cap" nut:

Genius!

I've gone with AS394 for now. If there's an issue with matching the unit with MAT02 once I've built everything up, I'll cross that bridge then.

Thanks for the help all.

Andy

 

[KA-Electonics.com]

Alfa make so many cool things. Semiconductor production - ALFA -Riga Latvia Europe
Cabintech is a very good resource. Cabintech Global LLC

Let us know how the AS394 work out.

 

[TwentyTrees]

Thanks, will do!