SET 45 and their (real) required speaker efficiency


Hello,

Gosh, wasn't sure if to post in the speaker or amp sections. But here it is. 

I've got a Finale/Triode Lab F-300B Monoblock amp paired with the Omega Super Alnico monitors stated at 94.5db efficiency. It does very well with this amp and I'm very happy with the pair overall. With classical being 90% of what I listen to, I guess I haven't really pushed the system to its limits, but it delivers plenty of what I like with acoustic instruments. Harmonics (texture and timbre), tone, minor dynamic shifts (musicianship), etc.

My question is for SET 45 tube owners and recommended speaker efficiency. Do the 2 watts from these amps have a 'real world' threshold where they simply can't deliver under a certain efficiency rating? So, for example, my speakers state 2 watts and up are enough. But I've had a few people tell me that 94.5db is not enough for this SET. However, on the Decware site, it does put a pair of Omega speakers on it's site as, what I imagine being a suitable speaker to pair with their 2 watt amps. The amp I'm thinking of getting will have Hashimoto transformers and a 20 watt output transformer. Not sure if that will give a bit more for the speaker to use or not. Also, are speakers w/o crossovers something to consider if I need to go look for another pair of speakers? Finally, what would your experience with the 45 SET amp suggest as far as the optimal efficiency rating for these tiny two watts?

Geesh, it's 5:40 am, no sleep yet, please ask a question if all the above sounds like someone hasn't had sleep yet.

Anyway thanks folks, really appreciate any suggestions to an optimal efficiency.

take care,
rob


vvcv
I really like my 45 SET and Omega Super 3 High Output XRS. Very musical combo. 
Hello ricwa,

such great news thanks man. I think i'll call Louis for sure on Monday to try and get his honest opinion on the amp I'm looking at, and what he thinks. I just realized the new Super Alnico tower is 97db. Looks like two exact drivers w/one w/o the tweeter. May be interesting to try a get a demo pair to listen to. 
Thanks jmolsberg. Another declaration of confidence in my amp of choice and current speakers. 
Finally, what would your experience with the 45 SET amp suggest as far as the optimal efficiency rating for these tiny two watts?
As with all things audio, it depends. It depends on your ears, your expectations, your gear (listed), the size, shape and construction of your room, how loudly (or softly) you typically play music and, mostly, your ears.

I ran a pair of Omega Super Alnico 6 monitors as my main speakers for a couple of years, paired most often w/ both a 2W 45 SET mono blocks or a 5W SE EL34 amp. I loved them and thought they were great for most non-headbanging music but weren't quite cutting it with large orchestral and opera pieces. Maybe it was the single driver or maybe it was the whizzer cone. I ended up replacing them with something completely different that isn't low-powered tube friendly. That's not to say I don't miss the Omegas - I do.

But to answer your question, 2W is enough when it's enough. And it's not when it's not. If you like the sound of the Omegas but you can't play loud enough, get an amp that puts out more horsepower. I had a McIntosh MC225 (25 W PP) and it really changed how the Omegas sounded. Not better or worse, just very different. If you don't like the sound of the Omegas then changing amps probably won't make you happy. My motto is speakers first: find a speaker you love and will work with your music and your room and then find the right amp to optimize the speaker. Others here may have a different opinion.

I just got a pair of 45 mono blocks and am pleasantly surprised with how they compare to my 300b amps. To my ears, my 45 set amps can play subjectively louder than my 300b's with less distortion. I often don't realize how loud the volume is when I am listening. Maybe the first watt is better?

All that aside, impedance is just as important as high sensitivity in matching set amps with speakers. The 8 ohm rating of your Omega speakers would be good for a 45 set amp if it is a flat 8 ohms with no major dips. A sensitivity of 94.5 db, while not ideal, would work okay too if that is truly the sensitivity of the speakers. Actual sensitivity measurements are usually lower than what the manufacturer provides (see, for example, the recent Stereophile review of the Volti Razz speakers). The bottom line is that I would try to get some real world speaker measurements before proceeding, as your speakers are perhaps on the cusp of what would and would not work with a flea watt amp.