McIntosh MC 601 Using two taps at the same Time


Has anyone use two taps at the same time 4ohms and 8ohms taps on a Mac amp? I usually use a biwire for my Vandersteen 2CE Sig II but I would like to separate the biwire as in, tap the lows on the 8ohms tap and tap the highs on the 4ohms tap to get a little more low end (bass). According to McIntosh, since Mac uses the autoformer, you can use two taps at the same time.
miketuason
I have MC501 mono's powering Vandersteen 3A signatures.I use two stereo pairs of speaker cables to bi-wire them.After trying all possible combinations.I use the 2 ohm taps for the lows,and the 4 ohm taps for the uppers.Sounds the best for me.I also utilized the same taps when I was using an internal bi-wire cable previously.As Mac states,using multiple taps is not an issue.
Great question. I have a pair of MC2200 amps driving 2Cis bi-wired using two separate pairs of cables and it never crossed my mind to try the two different taps at the same time. For some reason I thought it could damage the amp(s). Learned something new and will definitely try it when I get home. Thanks for asking the question.
Just as a follow up, I didn’t get a chance to actually try the different connection options but found these comments in the MC2200 owners manual. Not sure if they apply to other Autoformer design McIntosh amps:
"If a load impedance is used that is lower than the output
impedance tap, then reduced power and possible distortion
will result. If a load impedance is used that is higher than
the output impedance tap, then neither the signal nor the
amplifier will be harmed but the power available is limited."
And this:
"DAMPING FACTOR:
STEREO
16 at 1 ohm output, 50 at 2 ohms output, 30 at 4 ohms output,
16 at 8 ohms output".

So it looks like the taps have different output impedance and the taps with higher damping factor should theoretically give a "tighter" bass, all things being equal. Assuming the same behavior between MC501 and the MC2200, this might explain why denman prefers the 2 ohm tap for the lows.

So to make it more simple, if you have an 8 ohms Speakers, you use the 8 ohms tap and if you have a 4 ohms Speakers, you use the 4 ohms tap and so on. Yes?
So to make it more simple, if you have an 8 ohms Speakers, you use the 8 ohms tap and if you have a 4 ohms Speakers, you use the 4 ohms tap and so on. Yes?
That's the idea but the fact is that an 8 ohm speaker has a varying impedance across the frequency spectrum so the outcome is not always predictable. When I tried the different taps - 2, 4, and 8 ohm, with my 2Cis - biwired to a single tap, I could hear an audible difference mostly in the size and shape of the soundstage with the 8 ohm giving the widest and deepest. l'll try the multi-tap scenario soon, just dragging my feet to cut/break the nicely soldered connections. 
Miketuason, it is difficult to connect 2 spades in one tap, for biwiring, perhaps that is what the OP is referring to as well.

Search for spade to banana adaptor for McIntosh and there are plenty of low price high quality options out there.