300B Tube Amps with 15/16 Watts Per Channel?


Felix Audio makes the dual 300B amp "Lybra"--are there any other manufacturers of that gear?.Does anyone have experience using two each 300B tube amps modified to be two monoblocks with 15/16 watts output power each? If yes, did you hear any difference in the exquisite 300B sound other than more power? All experiences and thoughts appreciated. (Yes, expense is already noted)

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I built a parallel 300B SET based on an ANK kit with a lot of modifications. I don’t have much experience with a single tube SET, but my amps sound very nice. Check out my virtual system. 

What you want is a Parallel Single Ended 300B amplifier...Look at:
 BorderPatrol S20EXD...
Fezz Audio Lybra...
World Audio Design...
Audio Space Reference 3.1 & Audio Space AS-6M...
Manley Labs Neo-Classic SE/PP 300B.........

You could also do a pushpull 300B amp that will get you closer to 25 watts.

Spatial Audio lab produces dual 300b  monoblocks designed by Don Sachs, ‘Blackbirds’  24wpc. 
 

If you don't mind assembling a kit, Bottlehead makes a 300B model called the Kaiju that can be configured to work as a 16W monoblock amp. I have the Kaiju configured in stereo mode and am very pleased with its sound quality. I can only imagine that the Kaiju in monoblock form would sound just as good or better, but with more power. Bottlehead kits are very complete with superb instructions, which makes for a relatively easy build.

Absolutely one of the best is Aric Audio. Aric makes a 300b parallel SET amp, the Super 300b PSET.

Allnic Audio A-6000 monos run 2 or 4 x EML 300 BXLS per side.  

Best tube amps I've ever found.  Highly linear and powerful w the beauty of tubes. 

Thanks to everyone who replied to my question and provided so many good recommendations..Looks like I need to spend more time at audio shows and retailers :)....

Art Audio Diavolo Copper Ref SET. Verdantaudio.com

I think it maxes at 13wpc, but you must use the EML 300BXLS. You would need to discuss having the amp wired to the higher voltage psu transformer windings and bias circuit adjustment for that tube to get the higher wattage. The Western Electric 91a Boasts 20wpc with their 300b and special circuit and solid-stage rectification, (I prefer tube rectification for SET), but that 20wpc is at 10% distortion which is an order of magnitude more than necessary to get the 2nd/3rd harmonic distortion which provides the euphonic magic along with that floaty liquidity and palpable midrange and eerie micro-dynamics . I don't do parallel SET (anymore) after owning the ALLNIC (Quad-Parallel 300bxls monoblocks which will give you 60wpc, but only by using quad-pairs of eml 300bxls (KR AUDIO BXLS MAY ALSO WORK). $25k New or $10k-15k used and theg are made in  S.Korea). I don’t recommend parallel-set because it’s not as pure sounding lacking some magic (though better than pushpull or ultra-linear or the phony triode-mode by disabling 2 stages using a pentode) , very expensive, it’s a class A amp with massive heat output aka a space-heater, retubing is way more expensive especially for EML or KR 300bxls. I’ve done all of this before. Do you like running the ac in winter all the time? 

i now own a muzishare R100 805 model Don’t be confused the 300b is only a Driver-tube for the 805 triode) It produces a real 50wpc and for the money or 4x the money, I really love it. I run TOTL Psvane Acme 805 ($650-$850 ebay) and its the best bang for my buck ive ever had with a SET AMP. It Drives my Legacy Audio Whispers XDS dual-open-baffle speaker exquisitely . Specifically it drives each speaker’s 4x 7” mid-woofers, and the dual AMT custom midrange and tweeter. The open-baffle 15” bass drivers (humblebrag, all eight of them) are actively powered by 500wpc ICE Class D amplifiers. The speakers are 4ohm 94db.
Ive been doing SET Tube amplifiers for most of my 40 years in the hobby. If 50wpc is overkill, the R100 845 version ($2800-$3500) or the $5k-$6k Flagship X30 845 muzishare.will give you 25wpc. I like the PREMIUM PSVANE ACME 805 tube A LOT! I may buy the X30 845 next myself. (Skip the Line Magnetic or Willsenton) Best of luck.

 

Don't listen to @brianlucey 😝, I am struggling to remember if I bought his used pair of Allnic A6000 monoblocks. I could be wrong! This much I will admit: i neglected to mention the model in my previous post, I couldn't be happier with the transaction, great packaging and like new condition, he is correct regarding running two pairs vs quad 300bxls, they are meticulously crafted, and we're very impressive driving anything, but between the heat, retubng expense, and that they were IMHO almost too clean, aiming for superb dynamics trading something in tonal colors, and some delicacy with micro-dynamics. I believe the feedback design might be what caused this.

I sold my A-6000 for lower wattage single ended triodes - all you describe is regained.  Parallel circuits are difficult to engineer and that is the trade off.  But the A-6000 is far superior to push-pull - in my exceedingly subjective opinion. 

The other option is to look at 845 amps that use 300b(s) to drive the 845 tube. 

I had some 300b PP Zero NFB Mono’s with 20 Watts @ 4 ohms built by Ken Uesugi of Japan and they sound stellar and the price is a STEAL; my inter stage transformers are silver and made my Luxman which are different than the ones show in the link below:

https://otomon.net/products/detail/72

I have been using mines for 11 months and they have been rock solid smiley

Wig

@wig I am looking for 300b Zero NFB amps myself and the Otoman labs amp might be the ticket. Since most in US will be buying blind, could you describe a bit more of your experience with these amps ? What preamp are you pairing with it ?