Paul,
Thanks for routing the suggested change to The Man. <g>
I have gotten a few responses so far to the impedance question. I thought you might be interested, so here are all three:
Answer # 1:
If you stay with the original xovers, I would use the 16 ohm tap. If you switch to an xover that has a bi-wire strap connecting the LF and the HF, I would run the LF and HF on separate taps depending on room acoustics.
Answer #2:
For stock k-horns and crossovers I would say 8 ohm taps. I have tried different taps pon amps with my k-horns and 8 ohms always seemed to work best for me. IIRC the stock corssovers were designed for 8 ohms, of this I am pretty sure. I am also sure someone will chime in very soon with a definitive answer.
Answer #3:
If you are building some 2A3 amps, I would also take the time and spend the money to, at the very least, update the crossovers in your K-Horns. The basic change would be the capacitors, as these would have drifted out of spec over the years. hYou could actually do that first and compare the sound with your present amp.
The other possibility would be to build a totally new set of crossovers that are a constant impedance, something that your 2A3 amps (most tube amps) will like. I built a low order, constant impedance set of crossovers for my La Scalas, and power them with my 2A3 amps and they are simply magic.
The lower order crossovers work for me for a couple of reasons. I don't play music at extreme volumes, which means they still sound good. At higher levels, the driver overlap can get a little mushy and blurred. The crossovers that are higher order or extreme slope, for most people don't sound as good until they are driven at higher levels. Since the 2A3 amps are only 3.5 watts, this is more difficult and the amps will give out...
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I have to admit I like answer #3-- this is the kind of thing I would do, and it has been tested by a K-horn user. I don't know whether the fellow who recommended eight ohms had current crossovers, or my crossovers, however. I think I am going to wire them at 8 ohms for now, though I'm not sure what happens when you wire output transformers to 8 ohms and the speaker is really 16. I seem to remember one fellow on these forums asking about Z-out for the various impedance wirings, and his experience was the lower impedance he wired for, the better his Hereseys sounded. From this I conclude, probably erroneously, that it is better to wire for too low than too high. Hence, 8 ohms....
We will see! [grin]
