Cap change advise for a Symphonies V2 preamp?

Hi South43- As with tube rolling; much depends on what flavor of sound you are after. If softer/warmer: you might try some paper in oil(like NOS Jensens), for more resolution/detail/transparency: Vcap's TfTf and somewhere closer to the middle: Vcap's OIMP. I'm going to try Vcap TfCu's in my Cary monoblocks, as soon as they release the .47uF 600v value. Of course, what you can use depends on the room you have in your chassis, and the values required.

DON'T use a hot-melt gun! That kind of heat will cause damage to almost ANY of the higher-end caps. Rather, use double sided tape, or some of these sticky backed cable tie mounts( http://us.element-14.com/panduit/abmm-a-c/4-way-cable-tie-mount/dp/78F622?in_merch=Popular%20Products&in_merch=Popular%20Products&MER=PPSO_N_C_EverywhereElse_None ) and cable ties, pulled JUST tight enough to gently hold the cap(no crush). They should be available at any good electronics store. It's not surprising that the designer of the pre, does not want to communicate about you rethinking his design. Doing the caps that you do have values for should yield much. Go for it!

At the bottom of this page( http://www.partsconnexion.com/t/catalog/CapacitorsFilm.html ) there are a variety of caps on which you can click. I talked to them the other day, and was told they would be carrying the Vcap CuTf, "soon". ( http://www.v-cap.com/copper-teflon-capacitors.php ) I've also used DynamiCap, Multicap and auriCAP(all matched to 1%, by Michael Percy) in the past with great results(depends on what you're replacing). Something simple to bring life(blacker background/cleaner highs) to your power amp: Change the rectifier section to fast/soft recovery diodes( http://www.partsconnexion.com/t/catalog/semiconductors.html ), unless it has a tube rectifier. Tweaking/modding can be VERY rewarding, if one is interested in achieving the closest approximation of live music, in the home.

BTW: If the values that you have are .22uF/200V and .47uF/400V, the other two caps should be 1uF/400V. Keep your eyes open for a NOS(50's), Mullard(Blackburn plant) 6X4 rectifier, for the preamp.

Of course simple(less in the signal path) is best, and caps are what nature(as in, "live music") seems to abhor the most. Ergo: my recommendations are always to go with the best/least obtrusive in any application. Of the ones you've mentioned, I'd personally go with the auriCAPs. Be certain to observe the proper orientation of the caps in your circuit:( http://www.audience-av.com/capacitors/a_applications.php ), keep your leads as short as possible, and find some WBT lead-free silver solder(very low melting point). Have fun!

The site I posted(last) explains which lead(black) is connected to the outer foil of the(auriCAP) cap, which should be connected to the signal source in your case(coupling), for best noise rejection. Most of the better caps' leads are designated in some way to indicate proper orientation.