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Trying different output impedance taps with tube amps

My Antique Sound Lab Tulip 2A3 SET amp has 4, 8 and 16 ohm taps. I had been running the 8 ohm taps, and had a friend over to listen. He suggested the 4 ohm taps might be a better match for my speakers (Audio Note AN-Es). He was right, and it made a really nice improvement.

If you have multiple taps on your amp(s) and have never tried the other ones, or haven't for a while, it's worth a shot. Even if you are using the recommended or “right” ones for your speakers, you might be surprised.
tommylion
noromance's avatar
noromance
9,538 posts
 
My Quad ESLs (1957) need 16R taps on my tube amps with 8 and 4 ohms sounding progressively duller and colored. The difference is night and day. I guess it limits them to amps with 16 ohm taps.
commish1965
20 posts
 
My zu druid V speakers sound much better with the 8ohm taps on my prima luna HP.  It's not even close.
jandewitt
25 posts
 
I only have a 16 ohm tap on my old OTL tube amp and I am using a 16 ohm broadband loudspeakers from Ocellia. So I can’t compare, but I can say is that this works very, very well.
atmasphere's avatar
atmasphere
11,632 posts
 
I believe that Ralph has pointed out in the past that using the higher ohm tap results in less distortion, increased bandwidth and better efficiency.  
@charles1dad  Actually what I've said is that all amplifiers (tube or solid state) make less distortion into higher impedances; in the case of tube amps you also get wider bandwidth and greater efficiency.

Another way of putting this is if high quality audio reproduction is your goal, your amplifier dollar investment is best served by a loudspeaker of higher impedance- 8 ohms as opposed to 4 and 16 ohms as opposed to 8.
An additional benefit of 16 ohm loudspeakers is the speaker cable is far less critical for proper system sound whereas at 4 ohms its critical!
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