2. amps-preamps
  3. 159455-47476

VAC 70/70 mk3 tube rolling question

I recently purchased a VAC 70/70 mk3 s. Where can I find more information about the tubes diagram for the amp? I know it uses two 6sn7 per channel. Are there any differences in functionality between the two 6sn7 used for each channel? For example, do I need to use a matching pair of 6sn7 per channel?

I have one matched pair of RCA red base 6sn7 and a matched pair of Raytheon vt231 6sn7. The RCA are good for lush mids with 3d soundstage and Raytheon vt231are good for speed and accuracy.

They were meant to be used for the Schiit freya plus which uses a pair of 6sn7 for output stage and another pair of 6sn7 for voltage gain stage. Now since I already get a VAC renaissance 5 preamp, I am wondering if I can use my two pairs of 6sn7 on the VAC 70/70 amp.

My question is can I use one RCA + one Rayheon vt231 for each channel of the VAC? Or should I use a matched pair of 6sn7 for each channel? What are the recommended settings?

Also, any experiences about tube rolling on the VAC 70/70 mk3 are welcome. Like which 300B amps or 6sn7 combinations give you the best results.
yuhengdu_tiger

Showing 1 response by drrsutliff

drrsutliff
893 posts
 
Call the VAC factory and speak to Kevin or Brent. I believe the order will be the two most outside (L and R) should match and the two inner should match, but my memory may be incorrect.  They are always happy to welcome new members into the VAC family and will share where they believe each pair will work best (splitter or gain) and exactly which pair of tube sockets is each... so yes one of each for each channel but you need to know which sockets are what in the circuit. If your “red base” RCAs are the 5692 military versions I would suggest those to be in the amplification section and use the others as the splitters.
The manual is on the VAC website if you have not already seen it. http://www.vac-amps.com/manuals/Manual_Ren70-70.pdf
More to discover