Dynaco ST-70 and 6ohm speakers

High, I have a restored st-70 and a pair of Viena Acoustics Bach speakers that are labeled 6 ohms, should I use the 8 ohm or 4 ohm taps on the dynaco?
Thanks for your help,
Try them on both taps and see which sounds the most like music to you. That's what I did when I owned my modded ST-70 and Maggies(nominal 6ohm). I chose the 4ohm lead, and then installed Vampire 5 way binding posts(no chassis butchering necessary).
Hi and Thank you for your responce I have tryed them both and the 4 ohm taps do sound better to me. Its interesting that the Dynaco was able to drive magies Ive never had a pair but understand they are work best with high current amps.
Regards--- Guycom
Hi, It is true that a ST 70 will drive Magnepans. I used my modified ST 70 to drive a pair of MG12's. It did a pretty good job driving them but I wanted more bass control and I ended up with a Moscode 300 hybrid amp mainly because I wanted tighter bass.

I added two Dali 12" acoustic suspension subs and I had a crossover made based on the impedeance of my ST 70 and the Maggies started to roll off around 50Hz and the subs took over from there This solved the bass bloat problems. The MG12's blended very well with the subs and they had pretty good dynamics too. Of course I used the 4 ohm tap and I would not try that in a larger room. If you want to rock no way will the Dyna do the job without clipping.
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The ST-70 was working with the Maggies for me(at the time) because I was using it only above 200Hz. Well- That was with a 6db/oct slope, through a Dahlquist DQLP-1. Solid State on the bottom. I used(and modded) the combo with a variety of speakers for about 16 years.