Berning ZH270 Synergy

As a Berning owner, I can say that few amps can match Berning amps.

However, an amp is only a part of the package, and must be paired to speakers that will match it electrically, as well as sonically.

The ZH270 has an output impedance of 1.8 ohms with normal feedback, and higher with less feedback(switchable). Therefore, choosing speakers with a "tube friendly" impedance curve, staying above 4 ohms at all frequencies would be preferred. If you desire to select less feedback, then a speaker with even higher impedance at all frequencies would be desired. For best damping factor and less strain on the amp, I'd suggest using a speaker with a nominal 8 ohm impedance, that doesn't "swing" into low impedance dips, especially at lower frequencies. Even though this ZOTL has remarkable properties for an OTL, you have to observe proper system matching to get the best from it.

I believe that Sonus Faber also voices some of their speakers with the Berning ZH270. Saw it in the factory tour article in a past Sterophile.

Budrew,
I have the ZH270 matched with Piega P10's-the older grand piano black, not the newer aluminum models. The Piegas are rated at 89 db sensitivity and are a 4 ohm load, and I use them in a 17x14 room. I had some trepidation when I ordered it about it not having enough power,etc, but with the 30 day money back trial period I figured it was worth a try.
It was the best decision i ever made. It is a beautiful matchup. I get the best out of the Piega's ribbons, and the Berning is so good at both frequnecy extremes, it has no problem with the Piega's two 8 1/2 inch Vifa cones, and it provides exceptional dynamics. Plus, you get the flexibility of three feedback settings to tailor the degree of control the amp has over the drivers and the resulting sound.
I loved the sound running my sources direct into the Berning so much, but i am a lazy guy and needed a remote volume control. I ended up with a Placette Passive Linestage, also available on a 30 day trial, to go with the Berning. It preserved the Berning sound, improved the detail and soundstage with no loss of dynamics, and allows me to control source and volume via remote.
I am in sonic bliss. i heartily recommend the Berning under the parameters described above. It is a remarkable product, as is the Placette. I hope this is useful to you.
Flemguy

Budrew,
I have the Berning ZH270 and Coincident Total Eclipse speakers. The Totals are 94db and the Berning sounds amazing with them.

I am running the Berning with Gallo Nucleus Reference 2 speakers and the sound is magic. The sound is lightning fast with fantastic resolution and dynamics. As soon as I get home everyday the first thing I do is fire up the system. I tried running my Sony SCD-1 directly into the Berning, but quickly went back to my Supratek Syrah preamp. As great as the Berning is I consider the Supratek the heart of my system and that is saying a lot.