Dunlavy SC-IV Help


Hello gang,

I just did a passive Ohm reading on my pair of DAL SC-IVs. they are the signature version with the peerless woofers and vifa tweeters. Although the manual claims a mostly resistive load that is a nominal 5 ohms and varies little between 3 and 7.5 ohms across the audioband, I read a clear 2.3 to 2.5 ohms nominal on both speakers. All drivers are original and to my knowledge the crossovers have never been "tweaked". I use a Fluke 114 and have confirmed several other pairs of speakers with the ohm test.
Do any other DAL owners feel like slapping a meter on their speakers and letting me know if they see a similar reading?
Thanks in advance
128x128meadowman
That is about right for DC. (Remember the impedance is a function of frequency and you are only seeing the DC behaviour when using a multimeter)

See this plot
Shadorne,

Thanks. That makes a lot of sense. Now I can try the tube/hybrid Tm Evans Linear A on the SC-IVs.
Meadowman, I owned the sibling Duntech Princess speakers for many years and possibly because they had different drivers and therefore crossovers, the reputation for DAL speakers was they required less power and were an easier drive. My Princesses were rated at 4 ohms but the factory response curve showed two dips below 3 ohms, one at about 50 Hz, the other close to 10K Hz. The Princess was rated at 90 dB efficiency but any amp I tried with much less than 100 wpc simply fell on it's face, I believe in part due to the complexity of the crossover.

I know nothing about the Linear A other than Tom Evans' generally good reputation so what can you lose by trying?
Hello Meadowman,

I have had a pair of SCIV's for at least 10 years now. They are great speakers and are very easy to drive. I have had great luck using a Bel Canto SET40 which is a stereo amplifier using a single 845 directly heated triode in single ended mode per channel. This amp is very robust, putting out 35 watts rms with peaks of 75 watts. Very extended at the extremes with majic in the mids. I have also used a custom EL84 amp that puts out about 12-15 watts of pushpull. It has a beefy power supply and does amazingly well with these speakers too. The impedance is relatively low, but it is very flat, which tube amps like, and makes life easy for the amplifier.

Enjoy your speakers.....they are awesome!