Spectron vs any good tube amp.

Orpheus,
A good 300b SET amp can handle an 8 ohm load(even 4 ohm if it stays relatively flat).There`re so many 300b amps available and the quality-performance spectrum is very wide.The key is selecting one with top quality transformers and also a 'stout power supply'. There`re plenty of upper quality built SET amps to choose from.
My speakers are 94 db efficient and the amp just seems to coast with them. My room is 25x14x8 and opens(no wall) into a 26x18 room. I listen to jazz(a whole lot!) big band and increasingly more classical music. Generally my listening levels are 75-83 db and 10 feet from the speakers. At those levels the amp is using perhaps 1/10 of a watt. so there`s much headroom available.
Best Regards,

"My present speakers are 92DB, 8 ohm "

You don;t need ss power amplifier, IMO, if you like tube. Its very benign load.

I don;t know well 300b SET tubes but regarding the power needed for reproduction of the musical peak - your speakers will need much, much more then 1/10 of the watt or even 10 watts. Read small article on the subject written by Simon Thacher of Spectron (He is also tube man and work with Jud Barber of Joule-Electra on OTL tube amps)

http://www.enjoythemusic.com/magazine/manufacture/0708/index.html

All The Best,
Mike

Mike ,
Hello, It always come down to individual preference and listening levels. Not everyone wants or seeks very loud levels or peaks of 100db or more to enjoy their music. Cubic volume of the room is a factor(that`s why I listed my room size). With reasonably normal hearing and a good resolving system I believe low 70s-low 80s db is plenty loud,comfortable and 'safe' long term for your ears. These levels still allow headroom for louder musical peaks in maintaining music`s ebb and flow.

For jazz and classical you don`t have to blast the music to enjoy it. If your interest is pop,rock,electronic,hip-hop etc. at very loud levels then of course you`ll want(and require) more power. Really high volume levels/peaks IMO are too risky to one`s ears, but that`s obviously a personal decision.

My point to Orpheus is that under reasonable conditions he should be fine with a high quality 300b SET amp that usally provide 8-10 watts of power. If he wants 105-110 db peaks he`ll want a different amp.I have on a few occasions listen at 95-100 db and the sound was unsressed and very clear but I would`nt do this on a regular basis. Of course I don`t know what Orpheus`s preferences are.
Regards,

Charles1dad, just a FWIW: one of the reasons that you are less likely to listen to an SET at higher volume levels has to do with the way SETs make distortion as power increases.

As power levels drop towards zero the distortion becomes unmeasurable. As power increases, the lower-ordered harmonics (which are euphonic and so contribute to a 'lush' character in the amp) appear; somewhere at about 1/4 full power the higher-ordered harmonics come into play.

Now music has a lot of transients in it, so if the speaker is well matched to the amp these power levels will only be seen at the higher levels. The ear uses the 5th, 7th and 9th harmonics to figure out how loud a sound is, so when these distortions appear (and only on the transients) the result is that the ear perceives the sounds as louder than they really are and so there is no desire to turn it up any louder. This is why SETs have a reputation for being a lot more dynamic than their power capabilities would suggest.

Thank you Athmasphere for your posting. I always learn something new and ineresing from you.

However, my posting was completely misunderstood by Charles1dad (or, alernative I was unclear). I was not talking at all about loudness one would prefer in his own system and in his own room. Its subjective and I will not go there (but thank you again for explanation of what we hear when using SET)

I spoke ONLY about the reproduction of the musical peaks by real musical instruments. For example, I believe musical peak of Stenway is about 109 dB loudness at the position of about 10 feet from the piano.

So, if someone wants to reproduce accurate (i.e. not subjective) loudness of Steinway piano peak of 109 dB at 10 ft from speakers then one must produce appropriate and very specific power output from his/her power amplifier during this peak period. Measurments are provided by Simon from Spectron in his article but no way its 1/10 of the watt for 92 dB efficiency speaker with 8 Ohn nominal impedance.

Mike