MPP

[Joachim Gerhard]

Ultra low noise amplifiers

This is mighty interesting.

 

[merlin el mago]

Thanks to share Joachim.

 

[Joachim Gerhard]

It is more or less the same that Horowitz-Hill found and we a long time ago.
So Trolls, order them in quantity.

 

[saptemari]

Hello everyone,

I would like to build a MC Pre after this circuit of Mr. Hiraga Pr?ampli MC Hiraga

Can you please help with some suggestions, maybe including a reliable source for 2SB737?

Thank you!

 

[as_audio]

Any other low noise bipolar transistor can be used.

You can convert to npn transistors also:
- leave the circuit and transistor connections as they are,
- reverse polarity of both supplies in the schematic and
- reverse polarity of all electrolytic caps.

These hints are for the first picture in the linked article.

 

[RCruz]

It is more or less the same that Horowitz-Hill found and we a long time ago.
So Trolls, order them in quantity.

My choice for better bass:
ZTX1051A

ZTX690B

 

[Joachim Gerhard]

Saptemari, what cartridge do you use ?

 

[saptemari]

Saptemari, what cartridge do you use ?

I have two MC cartridges: Audiotechnica OC9 mark II and Denon DL-103R. I am currently using a pair of Hashimoto HM-3 SUT’s alternatively with a pair of Siemens T42/2e.

What do you think? According to your experience, would this SS preamp be better sounding than the SUT’s?

 

[esl 63]

Where have all the Low Noise Transistors Gone?

Interesting if SMD transistors has even lower noice?

 

[saptemari]

Thank you all for the help. I ordered four pcs. 2SB737. I hope they are genuine, they seem to be the real thing.

Merry Christmas to everyone!

 

[FdW]

Maybe a datasheet is useful here
See also here: https://linearaudio.net/sites/linearaudio.net/files/volume1ltejg.pdf

 

[MiiB]

I use the zeetex low rbb transistors in a phono stage, but I have also used biss transistors.. somehow they tend to sound more crisp and direct. Jfets are dull and noisy but not leaking. A real issue with bjts are base current. I have solved this by running them in floating balanced inputs and then really make an effort to pair the input transistor-pair. I have also made a servoed version where I mirror in the driving currents of each transistor and then let ithe nput DC differential drive the currents. The bjts are so quiet that only one pair is needed

 

[Joachim Gerhard]

The base currents can be trimmed too as we do in the Paradise.

 

[MiiB]

Yes i know

 

[RCruz]

I use the zeetex low rbb transistors in a phono stage, but I have also used biss transistors.. somehow they tend to sound more crisp and direct. Jfets are dull and noisy but not leaking. A real issue with bjts are base current. I have solved this by running them in floating balanced inputs and then really make an effort to pair the input transistor-pair. I have also made a servoed version where I mirror in the driving currents of each transistor and then let ithe nput DC differential drive the currents. The bjts are so quiet that only one pair is needed

I did not find jfets to be dull.... and they do sound good if well used

 

[Joachim Gerhard]

I made quiet JFet phonos too. You just have to parallel quite a few, cascoded, and you need to find the right types. That is very difficult concerning P-Channel types nowerdays.

 

[Joachim Gerhard]

Of cause you can make single ended ones with only n-types and still have DC coupling.
One example is the Pearl Two ( not my design ).

 

[RCruz]

I like the Pearl phono.... very good design.... maybe it could be improved with a good psu.

I am sure the psu is an integral part of any amp because it sings along with it.

I use a pair of jfets in the input of my phonostage... and it is quiet.

 

[kamis]

I like the Pearl phono.... very good design.... maybe it could be improved with a good psu.

I am sure the psu is an integral part of any amp because it sings along with it.

I use a pair of jfets in the input of my phonostage... and it is quiet.

How does it compare to Paradise?

 

[RCruz]

I have two MC cartridges: Audiotechnica OC9 mark II and Denon DL-103R. I am currently using a pair of Hashimoto HM-3 SUT’s alternatively with a pair of Siemens T42/2e.

What do you think? According to your experience, would this SS preamp be better sounding than the SUT’s?

Hi saptemari

This prepre can be very good if you care about the psu