SET 45 Amp Driving Dynamic Speakers

I thought 45s made 2W and one should run them at under 1W draw to keep distortion from growing much.

Is this what you mean by 0.75W?

You can get 2 watts out of them but if you really want to hear what they do its a good idea to run them at a lower voltage (where they will also last longer); in most applications in the old days they were run pretty conservatively. I used to have an old radio that used one and I think it was only good for 0.8 watts or so. But after 70 years in the field it still tested good...

Great thread.  Thanks to all.  I too am using 45s on AN-Es but I can hear the limitations. 

The BIG problem with 45 SET amps is finding the right speaker.  Those that can deliver close to a full range sound at reasonably high volume level and with decent tonal balance are primarily giant horn-loaded systems.  The trade-off is very high price, and having to place a very large system in an appropriate space.  If that trade-off is not feasible, one has to live with volume limitations when using moderately efficient speakers or the tonal quirks of some high-efficiency alternatives like single driver systems.  I have found such systems to be interesting, but, too colored and too restricted in both top and bottom frequency response to be usable with all kinds of music. 

I bring this up because I have, since this thread ended a few years ago, heard some notable exceptions.  The single driver, back-loaded horn systems by Charney Audio are very good all around speakers, capable of playing all sorts of music, and they are quite efficient.  I heard them working with SET 300b amps.  They come with various choices for the single driver.  I particularly liked the one with the AER driver.  For a much lower price point, I like the Rethm Bhaava.  This uses a high efficiency full range driver to cover the upper bass to treble range and has a built-in powered woofer to handle the low end. Like the Charney speakers, these are compact systems that can work in a large variety of rooms.  

Thank you for this.
If you've heard the Cube Audio Nenuphar single driver speaker, I wondering if you can speak to how it compares sonically to the Charney.
The folks at AVS showrooms seem to like single-driver speakers and I've heard them speak of both of these speakers.  They really love the Nenuphar.  I'm quite familiar with it but not the Charney.  

I have not heard the Nenuphar.  I am certainly interested in that speaker because it has gotten some favorable comments.  My understanding is that it employs transmission line loading which means it will not be as efficient as the Charney speakers.  But, if it offers good sound, I am certainly interested.  I should have also mention that I have heard, and liked both Voxativ full-range systems and a few other full-range systems employing Voxativ drivers.

I am surprised how much improvement full-range systems have undergone in recent years.  I the past, I've generally liked systems employing "full range" drivers as wide-range drivers in multi-way systems, but, I did like pure one-driver only full-range systems.  The Voxativ system I heard changed my mind to some extent, and the Charney, even more so, has altered my view.  Now, I need to hear the Nenuphar.