Where to go from XP-15? XP-17? XP-25?


I've been happy with the XP-15 for a number of years - first supporting my modded AR ES-1, then a VPI Classic 3, and now my Avenger (my final stop, I hope). I love the fine adjustability of MC loading and the gain which will support running carts down to about .2 mV. But with the Avenger I think I've reached a point where I should consider a move, in part because everything I find about the XP-25 seems to indicate it is far and away an improvement over the XP-15. With the inclusion of the XP-17, however, I'm now a little hesitant.

I run two arms on the Avenger, so it might suggest going to the XP-25 is an easy decision, plus the well regarded sound quality (I've heard the 25 a number of times, but not in my own system). OTOH the XP-17 is based on some of the same technology that's in the XP-25, plus it's a one box solution (I kind of like that). The questions out there for anyone who can help - has anyone been able to compare the XP-17 to the XP-25? How do they sound compared to each other? Would the XP-17 be considered a step up or at least equal to the XP-25? If the XP-17 is generally considered a must try next to the 25, I can always run it face into the rack and keep the back end exposed for tonearm and loading changes (not pretty, but effective).

I'm also a little concerned about any change in sound from the previous generation Pass gear to the new (12, 22, 17, 27). I've read, for example, multiple views back and forth between the .5 and .8 series amps, a few saying Pass' reduction in negative feedback and modification to the second harmonic character in the .8 are not to their liking. I hadn't heard if there's been such a (perceived) change in the small signal Pass devices.
tonyptony

Showing 6 responses by dgarretson

From what I've been able gather, the main improvement of the XP-27 are dual mono power supplies that improve the already excellent noise rejection of the XP-25.  I'm happy with my XP-25, the more so after replacing the stock loading resistors, coupling caps, and input RCAs with better pieces.
Replaced the loading resistors, which are clearly labeled, with Texas Components TX2575 nude resistors, and replaced the stock electrolytic and MKP coupling caps with ClarityCap 4.7uf CMR.  Replaced the stock Cardas RCAs with Bocchino Tomahawks and WBT Next Gen. Next step is to try a Less Loss 64x firewall in the power supply.  No reason that I can see to abandon the XP-25. 
@inna All products are built to cost. Improvements are always available, whether through trade-in or thoughtful modification.

I did it myself. You need good soldering and desoldering skills.  The Pass unit is easily disassembled. There is space for the larger coupling caps mounted on perf board raised above a small section of the main PCB. The Bocchino RCAs are solderless with compression fittings and heavy silver plating over solid copper base metal. Just remember that you will void the warranty, and if it ever needs service, Pass’s formal policy is to first return the unit to stock condition. I doubt they would care about the resistor and RCA changes, but you might have to reinstall the stock coupling caps.

PM for details and photos if you decide go for an XP-25.

I assume that you're thinking of a used XP-25?  If you're buying new, definitely go for the XP-27.  You can always do the same mods to that should you feel the urge. 
Whichever you go for, add a Less Loss 64x Firewall to your Xmas list.  I spent the afternoon juggling three of these through the system.  Of six components evaluated with the 64x, the XP-25 benefitted most.