I would describe my listenng and music preferences as similar to yours. Tube Compliment for VTL 2.5 is listed as:
2 x 12AU7, 2 x 12AT7. I would think your Sylvania's would be pretty nice but I have no idea on your 6350s. Black plates and D getters are a good start on most input tubes though IMHO. NOS Telefunken 12AU7s and Bugle Boy 12AT7s might be a nice combo to try. They are smooth and lively and let the amp's warmth come through. In your amps, I think the JJ EL84s are as good as you can do for new production, I have these in a Ming Da amp and were a big improvement over Sovteks. You may have to go to NOS EL84s to do better. I will let others recommend NOS EL84s. These can get pretty pricey but not as bad as NOS EL34s or KT88s. Overall I am betting your current tube set is pretty darn good.
However, if I had your Spendors, I might look to go to an EL34 tube amp(s). You will generate more power and they will give you a fuller sounstage and mid range warmth in spades. Sveltlana or SED EL34s are hard to beat for new production and sound great to me. I wonder if the EL84s are giving you enough power to drive the those excellent Spendors at I am guessing 20/25 watts per side.
Another upgrade you may consider is adding a good inexpensive DAC (V-Dac ii maybe) to your mix and bypassing the Regas and just use it for a transport. This would give you better sound and also give you stored music playback capability if you want to venture there down the road. I know that was not your question, just a thought.
2 x 12AU7, 2 x 12AT7. I would think your Sylvania's would be pretty nice but I have no idea on your 6350s. Black plates and D getters are a good start on most input tubes though IMHO. NOS Telefunken 12AU7s and Bugle Boy 12AT7s might be a nice combo to try. They are smooth and lively and let the amp's warmth come through. In your amps, I think the JJ EL84s are as good as you can do for new production, I have these in a Ming Da amp and were a big improvement over Sovteks. You may have to go to NOS EL84s to do better. I will let others recommend NOS EL84s. These can get pretty pricey but not as bad as NOS EL34s or KT88s. Overall I am betting your current tube set is pretty darn good.
However, if I had your Spendors, I might look to go to an EL34 tube amp(s). You will generate more power and they will give you a fuller sounstage and mid range warmth in spades. Sveltlana or SED EL34s are hard to beat for new production and sound great to me. I wonder if the EL84s are giving you enough power to drive the those excellent Spendors at I am guessing 20/25 watts per side.
Another upgrade you may consider is adding a good inexpensive DAC (V-Dac ii maybe) to your mix and bypassing the Regas and just use it for a transport. This would give you better sound and also give you stored music playback capability if you want to venture there down the road. I know that was not your question, just a thought.