Lately I took home a pair of great looking and very impressive sounding Crystalvox (small russian brand) speakers. The speakers are big, use 3 8 inch woofers and have incredibly smooth highs. The problem is that they are rated 12 Ohm nominal and 8 Ohm minimal. With McIntosh the bass is rather loose. I put on my Mac 6900 on 8 Ohm and while I like the sound overall I can't help but wonder - what kind of amps do people usually use with 12 Ohm speakers?
Am sure that someone else will, chime in here but that Mac is wasted or even inappropriate with that speaker.Can run on probably (without knowing sensitivity rating) but S.E.T amps or 6 watts to 18 Watts would be a choice (really affordable stuff like Almarro).For solid state T power like Redwine or Pass First Watt would probably sound great (and give better bass control if not harmonics of tubes).Then you could go with a 40-60 watt push pull tube amp etc.I have heard some folks just think that 12 ohm coil speakers don't control bass (Google Zu Tone and you'll get and add for a pair of 12 ohm Tone monitors but that could much smaller bass drivers than you have or what's inherent with 12 ohm).So I think that you don't need that big an amp and could get a better match.The load versus the amp design and bass control well I want to hear others or will call my sound engineer buddy about that.But something from 15 to 60 watts depending on what kind of sound you like is what I think will be best.How'd you end up with these anyway?Check reviews of the Zu's to see matches with other 12 ohm designs. Chazz
Bob_reynolds, its pretty easy when you've been doing for a living. If you look at the speaker, it is 12 ohms in the woofers and 8 ohms in the mids and highs. I had to surf their website a bit to figure out what speaker it is and it did not hurt to have someone on staff that knows a little Russian.
Anyway, an impedance curve like that is easy for tubes in general.
If you have a mismatch, wouldn't it be easy to just install a resistor in parallel across the speaker terminals to lower the impedance that your amplifier is seeing? Or use the optimal amplifier - an OTL.
Conventional tube amplification has a transformer to reduce the native output impedance of amplifier to the 8 ohm standard. OTL means output transformerless. In order to avoid output transformers and the problems they can introduce, some people choose to use an OTL and appropriately high impedance speakers. Since you have the 12 ohm speakers, you should talk with Atmasphere. He makes the amps you need.