2. amps-preamps
  3. 157624-118117

Which one to choose between two 80K$ tube amps?

There are two interesting 80K$ tube amps on sale at Audiogon.

https://www.audiogon.com/listings/lis9jhj0-david-berning-co-211-845-otl-tube

The first one is David Berning OTL design with output of 60 Watts.

it looks beautiful. But I had never used OTL amp yet.

I am curious how it sounds with high efficiency speaker.

https://www.audiogon.com/listings/lisa27ii-jadis-ja800-flagship-tube-amplifier-six-chassis-best-ever-made-nos-new-old-stock-tube

The second one is Jadis JA800 with 6 pieces and 400watts.

I had used JA500  (only 4 pieces with 350 Watts) from 2000 to 2002 to drive B&W Notilus 801 with utmost authority and unbelievable slam.

It was kind of lifetime experience to own this beautiful and overbearing monster.

But I could not use it during summer time in modest size room.

Thus I let it go and got Silbatone 300B SET amp to drive efficient full range speaker.

350 Watt to 8 Watt

If you have money or hit the Jackpot, which one will you go for?




128x128shkong78
shkong78's avatar
shkong78 OP
1,485 posts
 
I had this post to find out which one people prefer between high power tube and Small power quality tube one.

I have Silbatone 300B SET with silver foiled output transformer.

With WE 300B made in 40’s, it give excellent details, transparent, wide and deep soundstage.

But it does not have enough headroom in my listening space with high vault.


I may get horn speaker with more than 105 db/W efficiency to work with Silbatone in the future.


Or I may drive using active crossover to feed only 50hz or high to Silbaton and 50hz below to my two 18 inches Scaena subwoofers.

Since I had never used OTL, I am also intrigued with one that made by Atma-sphere.


But I am not in a hurry since I am also happy with Line Magnetic 508 48 Watts SET after lot of tube rolling.

It give enough headroom and bass control so that I may not need to use subwoofer.
gasbose's avatar
gasbose
82 posts
 
Bah! silly question.., at that price you should buy BOTH!!
atmasphere's avatar
atmasphere
11,983 posts
 
But, is 3rd order harmonic distortion as easily/naturally tolerated by the human ear as is 2nd order harmonic distortion which is quite well tolerated. Some would say that in fact 2nd order Harmonic distortion is congruent with human hearing.
@charles1dad 
The short answer is 'yes'. The ear treats both *exactly* the same. What *does not work* is if the amp has low distortion, but the distortion it has is mostly higher ordered harmonics (5th and above). Such amps tend to sound bright and harsh, compared to an amplifier that has a predominate 2nd or 3rd. The reason that so many push-pull amps get docked for their sound as opposed to an SET is that when you combine a single-ended voltage amplifier with a push-pull output, that type of topology tends to produce a noticeable 5th harmonic, which makes the amp less musical.


The only way I've found to get around that is to avoid that sort of topology- either go entirely single-ended and get that 2nd harmonic or go entirely fully differential and get a 3rd harmonic (although at about 1/10th the level that the 2nd shows up in a single-ended circuit). Since the ear is relatively insensitive to either other than contributing to 'warmth', 'body' and the like, this seems to be the way to go since you can't put enough feedback on a tube amp to really tame the distortion properly (or most solid state amps for that matter)- you wind up just making it brighter and harsher.
david_ten
5,480 posts
 
@atmasphere   Ralph, thanks for the discussion on this. Helpful, educational and appreciated.

The only way I've found to get around that is to avoid that sort of topology- either go entirely single-ended and get that 2nd harmonic or go entirely fully differential and get a 3rd harmonic (although at about 1/10th the level that the 2nd shows up in a single-ended circuit). Since the ear is relatively insensitive to either other than contributing to 'warmth', 'body' and the like, this seems to be the way to go since you can't put enough feedback on a tube amp to really tame the distortion properly (or most solid state amps for that matter)- you wind up just making it brighter and harsher.

charles1dad's avatar
charles1dad
10,250 posts
 

Ralph,

Thanks for that explanation, it makes  sense,and explains (to some extent anyway)  what/why I heard differently between my SET (class A triode 300b) and my 100 watt push pull( class A/B pentode tubed 6550) amplifiers. Some degree of 5th harmonic distortion presence.

Charles.

More to discover