4 ohm tap vs 8 ohm tap

Of course the output tubes are always connected to the full primary winding of the transformer. So everyone is talking about the secondary windings, 4 vs 8 ohms. However, when you put an 8ohm load on the 4 ohm tap (or 4 on 8) you have changed the impedance loading on the output tubes, even though you never moved their wires. This probably affects the operating characteristics of the tubes.

No taps on my Crown PS-200s. The spec sheet says it supports 4, 8 and 16 ohm impedance. 170 wpc at 4 ohm, 100 wpc at 8 ohm, 55 wpc at 16 ohm - max average at 0.1% THD. Just swapped in a lovely pair of new Wharfedate Liniton Heritage Speakers listed at nominal 6 ohm, dipping to just under 4 ohm.

Still breaking in the speakers but they seem to sound best with the Crown at full attenuation, unpowered Shitt preamp with the input pot about 50% and system volume controlled by the DAC streamer input level. The Lintons are 3-way double rear ported, warm and rich with a wide dispersion range. The '70s called, they want their throwback box speakers back :)

Nice  18 yr old thread revival…..

FWIW I tried the 4 OHM taps on my setup and although my speakers are rated as "8 ohm compatible" and are more like 4 ohm nominal. I felt they were a bit constrained on the 4 ohm tap and soundstage shrunk a bit. That surprised me.

 

After a few LP's I began to not hear the bass. So after you all confirmed that I would not damage anything, I switched back to the 4 ohm tao. The bass is back.

The suspension of any loudspeaker takes a while to break in. You might try the 8 Ohm taps again in a few weeks and see if the bass is still missing. The 8 Ohm tap is more efficient by a few Watts, depending on the output power the amp is capable of. That in itself isn't a big deal.

The load on the power tubes is much higher if the 4 Ohm tap is used on an 8 Ohm speaker. This might mean less power from the amp, but might also mean less distortion (less distortion = greater transparency). So its always worth trying.