Sjöström Audio - QSX Mark II Phono Amp

[GlidingDutchman]

Reading threads here seeing how everyone searches for the ultimate phono amp I started to wonder why nobody say anything about "our own DIY man" Per Anders Sjöström's QSX Mark II Phono Amp.

It is a very elegant design that solves most problems - to me, compared to all other designs the best!

Lets discuss this amplifier! Per?

http://sjostromaudio.com/joomla/inde...d=69&Itemid=27

Dewald

[GlidingDutchman]

Nobody?

D

[jacco vermeulen]

What's there to say ?

It uses a cement truck of weeny transistors, but a lot of them are for various current sources and quite a few in parallel at the input stage to lower the noise level.
Fully symmetrical, DC-coupled and the cascodes makes it mighty fast.
Only thing i'd rather have seen would be an all symmetrical and vertical EQ instead of horizontal, but i'm not in a lecture mood.
Trouble for you is that you'll be heading into expensive turntable waters if you assemble the Sjöström MKII.

I hate it, and i hate P-A, but the QSX-II would fit rather nicely with my even more Extreme pre-amplifier and ExtremA power amp setup.

[GlidingDutchman]

Originally posted by jacco vermeulen
What's there to say ?

It uses a cement truck of weeny transistors, but a lot of them are for various current sources and quite a few in parallel at the input stage to lower the noise level.
Fully symmetrical, DC-coupled and the cascodes makes it mighty fast.
Only thing i'd rather have seen would be an all symmetrical and vertical EQ instead of horizontal, but i'm not in a lecture mood.
Trouble for you is that you'll be heading into expensive turntable waters if you assemble the Sjöström MKII.

I hate it, and i hate P-A, but the QSX-II would fit rather nicely with my even more Extreme pre-amplifier and ExtremA power amp setup.

So to sum it all it is more-or-less perfect in every way? Truely the ultimate phono pre-amp?

Hate Mr Anders? I am very well sure you are just kidding around.

Expensive turntables waters? I design turntables so it is not a problem for me...

D

[jacco vermeulen]

Originally posted by GlidingDutchman
just kidding around.

Yep, but don't tell anyone.

Depends, if you look at the numbers there's not much left you could wish for.
Just how well the specs will be is up to the one who builds it, which is pretty cool for a DIY design, no ?
If you like top notch linearity, really low noise, minimal distortion and you have no problem with NFB and DC-servos, then this looks like a very nice design.

I'm constantly amazed at the designs available to DIY persons nowadays, in particular when comparing something like this QSX phono-pre with e.g. an Elektor phono preamp with a mega-number of BC5** devices from the very early 1980s that took weeks of soldering and hand selecting TO92s.

Such a progress, but different people still have different preferences.
Me, i like MC cartridges, and balanced phono amps for moving coil.