2. amps-preamps
  3. 145841-18279

Recommendations on stuff to look at for upgrading a 300B SET amp

I built an Elekit 300B SET amp with tons of upgrades (e.g. Mudorf caps, Takman resistors, Lundhaul power supplies and output transformers, etc.).  I love the amp but I wanted to increase power from 8w a side to 16-25 while staying in the SET camp.  I'm just starting the process of brainstorming. I was thinking of 300B monoblocks,
845 tube integrated or similar.  I want to stay under $5k and would need to sell some stuff--I have a wonderful Primaluna HP integrated with a good chunk of tubes to sell if I did this. I love that amp too but I don't need the power with horn loudspeakers and found the 300B a better match.  

Here are some off the head thoughts:
Manley 300B monoblocks (have to be used to make budget)
Cayin
Line Magnetic 
Bottlehead 300B monoblock kit

I can do an integrated (but if it's an integrated I prefer a remote) or standalone amps and run them with a Schitt Freya I have for now.  Any advice will be appreciated in my research!  

128x128jbhiller
jbhiller's avatar
jbhiller OP
1,437 posts
 
@atmasphere , I know you to be super knowledgeable and I really appreciate what you are saying--so much so that it’s making me rethink the tube world, even if just for today. My speakers are 99dB efficient by specs. Maybe I’m just better off staying put.

I loved the push pull Primaluna with my PSB T2s (89dB) but I ventured into the 300B world and loved its intoxicating recreation of vocals. Maybe the solution is just to run two systems?

I almost know you have to be right about the 20-25% rule just by what I hear, which is nothing compared to your experience level as a builder of fine amps.


atmasphere's avatar
atmasphere
11,901 posts
 
Yes- I get what the allure of the SET is all about. That inner detail they are known for comes out of the fact that as power levels are reduced, the distortion decreases to unmeasurable. When the distortion is gone, detail is revealed. There aren't many push-pull amps for which that is the case, but there are a few.

The problem is that you can't get much bigger than the 300b; people have built SETs with dual 300bs that aren't too bad but they are only 3dB more powerful (which is to say, twice the power); the problem is that the way the ear hears, 3dB just isn't that much louder. If you really want to play things louder you need at minimum 6dB more power, which is 4x more power than you have now.  A 30 watt push pull amp that sounds nice isn't that hard to find, but an SET with that sort of power is challenging.


Its that, get more efficient speakers, or live with what you have....


jbhiller's avatar
jbhiller OP
1,437 posts
 
It may come down to living with what I have. At lower volumes the 300b SET is lovely. 

I’m curious to hear this as it is 4x my current output but still SET.  I’m not familiar with the power tube though. Drivers look to be 300bs though. https://www.line-magnetic.eu/en/products-line-magnetic-en/integrated-tube-amplifier-line-magnetic-en...

cal3713's avatar
cal3713
1,421 posts
 
@jbhiller I'd love to hear how that sounds in comparison if you ever take the plunge... Hope someone else weighs in too.
jbhiller's avatar
jbhiller OP
1,437 posts
 
@cal3713 

I'm going to hear several of the Line Magnetic products Monday morning.  I have to hear them 250 miles from home so I can't bring my loudspeakers but I will put them through the paces and check back in. 
More to discover