SEWA - Seven Watt Amplifier

[lineup]

Hi Mads!

Don't you want to make a PCB for the Atlantis MM pre??
I like your PCB design style!🙂

Greets:

Tyimo

Where can I find best info on
Atlantis MM preamp

I guess it is a RIAA phono amplifier, based on Tubes.
Am I right?

 

[hoktuna]

Hi mad_k!
I want to buy 6 boards rev.c

 

[Tyimo]

Hi Lineup!

Where can I find best info on
Atlantis MM preamp

I guess it is a RIAA phono amplifier, based on Tubes.
Am I right?

Mads posted it some "page" before.

No, it is a JFet based RIAA MM pre.

Greets:

Tyimo

 

[Mad_K]

Hi Mads!

Don't you want to make a PCB for the Atlantis MM pre??
I like your PCB design style!🙂

Greets:

Tyimo

I have made countless pcbs for Atlantis. Here's the rev.c layout (2 stereo pcbs):

 

[Mad_K]

Atlantis Rev.C assembly drawing:

 

[Mad_K]

Atlantis Rev.C BOM:

 

[Mad_K]

Atlantis Rev.C schematic again:

 

[lineup]

Hi Lineup!
Mads posted it some "page" before.

No, it is a JFet based RIAA MM pre.

I have made countless pcbs for Atlantis. Here's the rev.c layout (2 stereo pcbs):

Atlantis Rev.C schematic again:

Thanks, Tyimo for info and Mad_K
for full layout-pcb for Atlantis JFET MM Phono RIAA PreAmplifier

JFET amplifiers schematics are always interesting to look at
😉 Thanks

I put it into my Mad_K folder.
In my Tyimo folder I have several other good schematics.


lineup 😀 even has got a lineup folder with things contributed by him
not very empty folder!
http://lineup.awardspace.com/

 

[lineup]

Atlantis JFET RIAA phono preamplifier

I have had a closer look at Atlantis RIAA amplifier.

Is it okay to ask questions about it in here
or maybe better I would start a topic in Analogue forum
To explore a bit, this nice and straightforward JFET MM Phono RIAA.

There area couple of things I cant understand how it can really work.
Maybe because I have not designed very much using 2SK170GR JFET.


Regards
lineup 😎 will design some RIAA and/or Microphone amplifier project
for his website, later
http://lineup.awardspace.com/

 

[Mad_K]

The Atlantis is just a cascoded version of a well known standard JFET RIAA design called "The Pacific". There are a lot of variations floating around this forum and on the web 😉

Here's some links:

http://www.diyaudio.com/forums/showthread.php?s=&threadid=28223&perpage=10&highlight=&pagenumber=1

http://www.diyaudio.com/forums/showthread.php?s=&postid=252211&highlight=#post252211

http://www.diyaudio.com/forums/showthread.php?s=&threadid=36260&highlight=

http://www.passdiy.com/projects/pearlono1.htm

etc 😉

 

[lineup]

thanks
Mad_K

🙂

 

[Tyimo]

Thanks Mads for the Atlantis PCB!

You are great as always!🙂

Should I use IRF640 in the PSU of the BOZ?

Tyimo

 

[hoktuna]

Hej Mad_k
Jag glömde min adress i sista mailet.
Hans-Olof Karlsson
Lista Stenbo
635 14 Eskilstuna

 

[hoktuna]

The preamp. i am planing to use whith Sewa i a tube pre whith Lundahl 1674 trannii build last winter.I is from an artikel on raleighaudio.com

 

[Mad_K]

Thanks Mads for the Atlantis PCB!

You are great as always!🙂

Should I use IRF640 in the PSU of the BOZ?

Tyimo

Doesn't matter. Use what is most convenient 😉

 

[Mad_K]

Hej Mad_k
Jag glömde min adress i sista mailet.
Hans-Olof Karlsson
Lista Stenbo
635 14 Eskilstuna

Thank you Hans-Olof 😉

BTW, here is the PSU arrangement I have been using the last couple of years with my Atlantis preamps:

 

[aetosa]

Which is the suggested preamp for SEWA? BOZ or Atlantis?

 

[Mad_K]

Both 😉

 

[aetosa]

Atlantis has 40 db gain. SEWA needs preamp with 20 db (Post #578)
How can we change the gain in Atlantis?

 

[Mad_K]

The Atlantis is preamp with a RIAA equalized filter for use with turntables fitted with a moving magnet pickup. You use this between your turntable and the preamp (BOZ) driving your power amplifier (SEWA) 😉
If you don't own a turntable, you don't need it 😉