Nagra Jazz

hopefully someone can answer the following Nagra Jazz questions for me. I have been told that there are optional transformers which can be build in the Nagra and have a positive effect on the sound. Has anyone done this? Another question: is there anybody who uses the Jazz in combination with Spectral power amps?
Thank you for your input!
The Jazz has balancing input and output transformers.  So if you have a balanced source or a balanced amp, these should be a help.  I used to own a Nagra PLL with balanced output transformers...

Nagra winds their own transformers, they are very good at this.

The Jazz is a fantastic preamp, I've heard it many times at my dealers...I recently just bought a Nagra Classic Amp.  It's a special piece.

Sorry I can help you on the interfacing with a Spectral Amp...
Thank you! I love the looks of the classic amp. Does it have enough " juice"? Or in other words, are 100W sufficient for your speakers? Thanks again!
I prefer electronic balanced circuits over transformers.
My Classic amp has plenty of "juice"  I have a big room 25 ft wide, 30 ft long and 12ft ceilings plus a tough speaker's a fantastic amp.
Jfrech...I have seen that XLR connections are standard with the Jazz. Was this also the case with the PLL and was it possible to use XLR without the transformers?
I am really going to give the Classic Amp a listen! Now playing with Spectral 360 mono blocks.
I sold my Ayre MXR's for the Nagra Classic...Maybe that says a bit what I think about the Nagra...
Honestly I don't remember on the XLR's...for the PLL...I think the answer is yes...but the balancing transformers were a option like your Jazz.   Nagra knows what they are doing on dealer loves his input/outut transformers on his Jazz.  I just haven't heard it in my home...If you have a balanced source or amp...I think you are best to get this...
Thanks again! Since I am talking to a Nagra expert... why did you sell your PLL and which pre are you using now? Have you ever changed tubes yourself or is this better done by a specialist. At the moment I am offered a second hand jazz, pll and a cdp. A lot to consider...
Just bought a second-hand Nagra Jazz and CDP. Hope to receive them this week :-)
Only reason I sold the PLL was I fell in love with a preamp that cost 3x the PLL (Robert Koda K10), the Jazz wasn't out yet also.  Was sad to see the PLL go...really liked that preamp.  Any now since I bought a Nagra Classic amp, I could have had a all Nagra system :-)

It's pretty easy for you to change the tubes. Make sure the power is off !!  take to top off (just 4 hex bolts) and the tubes are simply pull out and push in the fresh tube.  Takes just about 2 minutes in total.  (make sure you don't get the tubes mixed up...they aren't all the same types)

I would not buy anything but Nagra tube sets.  They rigorously test and match their tubes.   I've tried others, and always go back to the Nagra factory tubes.   

You might consider a Nagra MPS (multi power supply) to power both your Jazz and CDP.  Should be a nice upgrade down the road.   Also a Nagra VFS (vibration free system) is another very nice upgrade.

Congratulations !!
Thank you Jfrech!
Luckily the VFS were included in the deal. As for the power supply, both the Jazz and CDP include  the Nagra ACPS II power supply. Now only one thing to do...sell my Spectral 360s and buy the Classic.
Enjoy the festive season!
Is it true that the Nagra Classic amp use SMPS power supply ?
This is a quote from their brochure on Nagra's website:

"The unit operates in pure class A over a very large power band and beyond in class AB. Each of the output stages is based on tandem MOSFET transistors of exceptional characteristics. Generally, assembly of
an equivalent output stage requires several pairs of transistors, which is difficult to achieve precisely. The simplicity of the CLASSIC AMP’s design is the key to its musicality. The input and driver stages also contribute equally to the overall performance and precision.

The Nagra CLASSIC AMP is characterised by its stability, irrespective of the loads placed upon it. The power circuits drew particular care in the design stage. They are based upon an innovative concept: An over- dimensioned transformer and a diode bridge are placed upstream of the PFC decoupling stage, used to actively correct the power factor. The filtering is achieved with a bank of capacitors, totalling 300 000 μF.

Designer and manufacturer of Nagra products

This supply concept, which ensures efficient energy transfer, allows immediate reaction on even the most abrupt transients."