6 Ohm 3-way speakers with tube amp - use 4 Ohm or 8 Ohm taps?

The bug has bitten again. My palms are itching. I'm thinking of getting a Coincident Dynamo SE power amp with 300B tubes, 8 WPC, to pair with my Zu Omen DW II in the bedroom system.

If that happens, it will free up my PrimaLuna Prologue Four push pull amp, 35 WPC. I will then want to pair it with my Wharfedale Diamond 10.7 towers, 6 Ohm, 90 dB.

Which tap would be better with them - 4 Ohm or 8;Ohm? Also up for discussion is whether it's a good pairing to begin with? Wharfedales like powerful SS amps, usually, and that's what I have them paired with now - a Parasound 2250 v.2.

If anyone has Diamond towers hooked to a medium powered tube amp - please chime in, I want to hear your feedback especially.

 

I found for my 6 ohm harbeths that the 4 ohm setting sounded more lively and dynamic than the 6 or 8. Going from 4 to 8 was noticeable—less so 8-6-4. My amp has a knob to do the change so it’s pretty easy.

My speakers are not 3 ways but they are less efficient then yours and I’m also running “mid power” tubes too at 32 w.

 

4 ohms will likely yield the most efficient transfer of power and result in better bass and milder highs. But try both, it won't hurt anything, and results can vary from expectations, in practice.
-Bill

 

For whatever it may be worth, McIntosh usually advises the use of 4 ohm taps when nominal speaker impedance is below 6.3 ohms.

 

I would tend to suspect the Mac people of knowing what they say regarding amps...

 

I'm running a Mac C28 pre into a PrimaLuna Prologue Four with KEF R5 three way (8 ohm) speakers. I have used the 8 ohm tap but like Bill said 4 ohms yield better bass and milder highs. It won't hurt the amp to use the 4 ohm tap.

 

Rating a speaker at 6 ohms is just another way of being able to publish a higher efficiency rating, rated at 8 ohms the speakers real efficiency is probably 87 or 88db. Use the tap that sounds best.

 

I have a PrimaLuna Dialogue Integrated, that I run with 2 Monitor Audio Silver 6 towers, rated at 8ohms and sometimes I switch to MA Silver 2, that are rated at 6 ohms. I find that the Silver 6 sound better at the 8 ohm taps, but the Silver 2 sound better at the 4 ohm. Also I need to rise the volume knob when I run the 2´s but both pairs sound very nice with my amp.

My 2 pair of speakers have the same efficiency rating, but somehow this explains why I have to rise the volume knob when I listen with the Silver 2 that are rated 6 ohms.

 

Ideally you could look at the speaker's impedance curve, if the impedance drops down to around 4 ohms in the upper bass, lower midrange, where there's lots of musical energy, you might be best with the 4 ohm tap. In fact it looks like that speaker is down to around 3 ohms at 120 Hz -- Wharfedale Diamond 10.7 loudspeaker Measurements .

 

Thanks.

 

I have the same MA speakers and a Primaluna Prologue Premium power amp. They do indeed have an impedance curve that dips to around 4 ohms in the lower midrange. Upscale Audio, who sold both products, also recommended the 4 ohm amplifier tap.