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MAT02, 03 Elektor preamp schematic

Elektor has in time past published two hi-end preamps using MAT02 and MAT03 dual transistors for the differential pair using +-15volts supply; one was with a DC offset nulling preset somewhere in the negative supply line and the other was with a servo using OP77.

I have somehow lost both the Elektor issues but would like to have the schematics. I have three assembled boards of the one with the servo. I would also like to try out the easier offset nulling arrangement.

Could someone please send me a scan of the entire articles OR if someone wants to sell their copies of Elektor containing the above, I will gladly buy them.

Thanks,
 
Dear Samuel!

I found a schematic in the Elektor's summer issue 1994. I think this is the drawing you mentioned.

Greetings from Vienna.

Wopo

:smash:
 

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If you need any more questions answered, i built the preamp.

I did the discrete versions with Mat02, Mat03.
And the full scale preamp with MC/MD version,
with MAT02/MAT03/OP27/OPA627 with relay switches.
Later i tossed out the voltage regulation and stepped up to batteryfed.
 
Jacco,

Which are the full scale versions that you mention? I have never seen them in Indian publications of Elektor.

I have not been able to source MAT03 so far. The ones that I bought were actually MAT02s reprinted as 03s; makes no sense. Hence, I used BC560 in the place of MAT03. This time around I'll use MPS8599/8099 (I forget which is the PNP type).

What do you think of the overall sound quality of the discrete preamp as compared to top of the line commercial offerings?

Could you please send me schematics and notes on the full versions and high quality supply schematics as well? Thanks in advance.
 
Elektor had "The Preamp" in the 80's, published in three parts; december 1986,januari 1987, februari 1987.

At the time a very pricy pre-amplifier to build, because of the choice of parts.
The design has relay switched entrances and exits, a phono stage that is switcheable from MC to MD,with a RIAA correction within 0.2 dB.
The basic design used 3 Mat02 double transistors and 4 OP27, and a whole array of different types of caps.
In august 1987 came an additional headphone amp for the preamp, that used OP50's.
In 1988 there was another additive, a nonbalanced to balanced
converter, and vice versa, again with OP27, and the AMP01,OP227 AND LM325(i think).
Later came the possibility to swap the 27's for OPA627, i used Burr Brown versions for all the active components from the beginning. Regular was PMI, some even used 5534(not recommended).
The build cost then including the chassis was well over $ 1000 , if all recommended parts were used.

Dieter Burmester was the leader in Europe in opamp preamp technology at the time.
Elektor's "preamp" was among the top of the range of the preamplifiers using precision operational amplifiers.

It performed very well combined with discrete class A power amplifiers on dynamic loudspeakers and Quad ESL's, the phono stage was particularly good for those years.

I have listened to it connected to the best of the Thorens range, combined with topnotch CD players/DAC's(tube versions), and connected to a number of class A amplifiers (pushpull, hybrid, tube, Aleph 0s )
In my view after replacing the BB OP27 for BB OPA627 when it came on the market it became a preamp that still ranks among the best in opamp pre's around.
Should be, the OPA627 and OPA637 still go for $45 each here in Holland.
The last mod's i did on the pre before going back to discrete again was forcing the IC's in class A and swapping the integrated LM317/337 voltage regulators for a battery powersupply with 22 individual discrete regulated current lines.

I think till now it was the best achievable with opamps.
Better means leaving IC's, going discrete to fewer stages, going single ended.
(For that i have been sucking on NP's mind since day one.)

I'll have to dig for the schematics, may even have pcb layouts.

The basic phono/line stage has been built by quite a number of people.

jacco
 
jacco,

I figured out what you are talking about. It is an IC based preamp, that Elektor called Top-of-the-line; its MM/MC stage used parallel connected MAT02s to reduce noise. Elektor issued a prelude to that publication on cost reduction with less exotic parts.

The preamp in question here is NOT that one but the ones posted on page 1 of this thread by wopo and moamps on my request. It is a totally discrete class A preamp line stage which utilises MAT02 and MAT03 for the input differential pair.

If it is possible, try out this preamp. It is simply fabulous.
 
I stated in my previous posting that i built both the early discrete/integrated version as well as the later discrete preamp circuits.
The fully integrated preamp Elektor designed in the 90's i built too.
Nowadays i stick to discrete, though i still love the opamp/mosfet class A headphone amplifier i built.
Probably will step up to discrete single ended for that too, as with single ended power and pre-amplifiers
jacco
 
Hello Samuel,


I have build this preamplifier about a year ago,
(the one with the bias servo) and I also think it is the best I have ever heard.
It is a pity that the MAT02-03's are out of production.

The sound is very detailed and transparent, I use on the input side the "The first cable" of van den Hull, and on the output a MIT terminator II cable, and as power amplifier I use an own design, based on differential input and 2SC5200/2SA1943 output transistors.

I have tested much combinations, but according to me (my taste
:D ), this is the best combination.

Best Regards and much listening fun with this preamp:
Nexus