What amp are you using with your Zu Essences?

Audiofeil's comment about OTLs and ZUs is incorrect. There don't seem to be any OTLs that will not drive the 6 ohm ZUs quite well.

Charles1dad, to answer that, if you can, take a look at the posts I have made here on audiogon and see if you come to that conclusion.

I don't like being called 'petty' but it may well be that that is the case. But there is more going on here than just this thread. In email conversation Bill expressed pretty much the same as he did in his last post just above, and I agree with him that he is not beholden to anyone regarding his own opinion.

However, you have to think that something is amiss with this statement:

For example, OTL amps are not ideal with the Omen Defs (6 ohm)

-not having heard any of our larger amplifiers with the ZUs, larger amps that handle 6 ohms easily, the statement is simply incorrect. Now if he had said 'smaller OTL's,' I would have cut him some slack, but even then with a set of ZEROs *any* smaller OTL can manage a set of ZUs just fine.

Now I have steered people away from our amps when they have had incompatible speakers, since it would do no good to sell someone on something that does not work- you only make them angry and there is no point in that. What Bill is not telling you though is he has not sold anything of ours nor have we heard from him in well over a year. He used to be one of our more active dealers. Its been my experience that when a dealer goes from active to inactive that its not out of chance.

We have a good working relationship with ZU and have had their speakers in house. Their speakers have always been an effortless load for most of our amps, but given that they are so easy to drive, the question most people have is how our smallest amp, the S-30, will do on the speaker. With the 6 ohm models you use a set of ZEROs and it works fine. With the higher impedance speakers you hook it up directly.
Zu has also built the speakers with higher impedances- it might be that it is just for the S-30 but I think they are targeting other amplifiers as well.

Charles1dad, What you say is true but about a different post- so in that we regard we are writing about two differnt things, but perhaps I take things much more literally than you.

What should be pointed out here is that a speaker that is 6 ohms is not going to match a transformer-coupled amp *ideally* either, unless that amplifier has a 6 ohm tap.

In the case of a small OTL, you only have to use a set of ZEROs. In the case of the ZERO, if you look that the website-

http://www.zeroimpedance.com

-you will see that the autoformer is treated more as a set of ratios than a specific impedance like 4 or 8 ohms. What this means is that if you have something like an S-30, and using the 2:1 ratio, that the amplifier will be driving a 36 ohm load. As far as the S-30 is concerned, this is ideal. The speaker does not need a *lot* of power, and the 45 watts that the S-30 will make in this example will really wake the speaker right up, better than most transformer-coupled amps.

Now you may not realize this but we used to make a product like the ZERO about 20 years ago, we stopped when the ZERO came out because it was a lot easier to explain the ZERO than it was our own product!

People were always asking 'Don't you obviate the OTL thing when you do that?' and the answer is no. Its funny how people had this story that an OTL had to be a certain way, and were equating the ZERO and its predecessor with regular output transformers, and there is a huge gulf between the two. The bottom line though is that it is just a way to make music, and I've never seen it as anything else.

That is why I always recommend to our dealers that they have a set of ZEROs on hand.