Primaluna Prologue 2 Upgrades

I too rolled the input tubes to Mullard for the AX7's & some French 1956 military's from La Radiotechnique for the AU7's, as suggested by Kevin Deal . The AU7's were not as important as the AX7's .
These made a huge difference in the warmth and tonality of the sound . They did not affect the great top end extension but did increase the base a bit . It also responded favorably to the EL-34's by Electro Harmonic's . The people at Upscale Audio stated that a power chord upgrade did not do much and therefore did not recommend it .

These changes increased the warmth/tonality , which is what I wanted to do . I felt that the stock tubes tended to make it sound like a SS unit . To me it is better but not generally what someone is looking for when trying to upgrade parts . For that type of better I would just change amps all together . You did not state what type of change it is that you are looking for with the upgrade .

Good Luck

Thanks for the replies.

I have gone through the tube changes, have Mullard NOS input/driver tubes and Svetlana EL34 output tubes. As you say Saki70, it does make a difference to the performance character of the amp, much more preferable to my ears.

I was really asking if anyone had done any major component changes such as cap and resistor changes to, probably, better specified/quality components.

The Prologue 2 is such a great amp once the tubes are changed to other ones, I was wondering if anyone had taken it any further, or whether it is possible to improve the performance.

EL34 NOS Tesla's were very good, but not at the level of NOS GEC KT88, so, before you do any change, I hope you have the funds to do that roll. KT88 are simply much better tubes, power and delicacy, where EL34 cant match.

I also tried NOS Tung Sols 6550 Smooth Black Plates and Sylvanias, but again, KT88 GEC's simply eats them for breakfast.

Looks like "Maxmad" acts as his screen name. GEC's are like a holy grail of tubes, probably about the same cost as the OP's amp in total... if you can find them. The Tung-sol KT-120's cost about $240 for a quad and blew away handily the Gold Lion KT-88's which I paid more for and in the past year.And while EL-34's sound sweet, I really can't live with a tube that snoozes on percussion.