Tube preamp topologies and music


I am searching for a tube power amplifier. I know very little (nothing) about what the pros and cons of tube topologies as they relate to certain types of music.

as an example, let’s take hard rock/heavy metal. It seems to be the consensus that say 300b single ended amps would be the wrong choice even if you had 100+db efficient speakers. Why is this?

Also, tube compliment. 211? EL84? 300B? I understand that they have power output differences, but what else?

 

I welcome everyone’s input.

gochurchgo

AudioXpress magazine had a good article on building a single-end 211 amp some years ago. The authors cautioned that such a project was not for the inexperienced! I suggest you track down this article! I no longer have my copy. Another valuable source of information on tube amp design are the issues of Sound Practices - recommended! Lastly, find issues of Glass Audio - more information on design and construction of tube amps.

A push-pull 211 can have double the power in watts of a PP KT88/6550 amp. With correspondingly more expensive parts/output transformer. Doubling the watts only gives a 3db increase in volume level. Not much!

A OP - As to your specific question, single ended 300B amps tend not to be very well controlled in the bass - even with efficient speakers.

A 300B valve is only good for a couple of watts before it starts to distort. A say eight to ten watt advertised SE 300B amp will not deliver that wattage at 1%THD.

So they are not a good choice for rock music.

The following link will give you a good overview of technical issues related to SE amps - a "high powered" one in this case.

 

There's a Jadis Defy 7 for sale now on eBay for $2636 + $105 shipping from The Music Room in Colorado. Six EL34:s per channel for 100 watts. It looks real nice with black transformer covers and gold chassis!