2. amps-preamps
  3. 1187899177

A question for technically astute

I have recently repurchased a Sophia Baby amp on A'gon at a really cheap. I suspect the cheap price the result of it being a 220 model. I think somebody move back from Europe with it. They bought a step transformer so it would work on 110. Anyway when I listened to it , I could swear that it had much better dynamics and slam than the first one I had. It seems like it can get much louder before compressing. The speakers might be a little more sensitive than before but not much. Is this my imagination or could this power arrangement make a difference?
128x128larryrx7
herman
2,252 posts
 
I don't think you can make any meaningful comparisons between 2 amps with different tubes played through 2 different speakers and going from memory on the sound of the first set up.
larryrx7's avatar
larryrx7 OP
137 posts
 
Thanks for the response..the step up transformer is boosting the voltage to 220 so I guess it could be producing a cleaner 220. As to my memory of the prior amp. It had the exact same tube complement. The only difference is the first was a 110 and this one is 220. Your right it is difficult to draw a comparison, but the difference particularly in bass slam seems noticeable for whatever reason. I wonder if the 220 produced by the step up transformer is giving the amp better juice to draw on? Does that sound reasonable?
pauly
1,012 posts
 
Hi Larry. Yes, it could be your step up transformer. When using a transformer, you need to over spec the transformer otherwise it will effect the sound in ways you mention. While this may be totally overkill, I wouldn't consider using one unless its capacity is 9 to 10 times that required by the amplifier. When over spec like that, they do not restrict the amp and serve to reduce the noise on the power lines.

You could could try a larger capacity xformer and see if it sound better or you could contact the vendor and see if the amplifier power transformer could be wired to 110v. I suggest you do the latter. Many amplifier transformers have multiple wiring options to accept 100, 115 and 220 volts.

Regards
Paul
larryrx7's avatar
larryrx7 OP
137 posts
 
Hi Paul...I am really happy with the sound right now..I think it sounds better than the 110 version..I was just trying to find out if that's possible and why.
pauly
1,012 posts
 
Hi Larry. Sorry - misread your post.

The transformer is filtering out noise in the power lines. The short of that is that it translates to a B+ voltage in your amp with less noise and ripple.

That would not (to my knowledge) give you more dynamics or slam though, but it would allow the amp to resolve low-level detail a lot better.

I think the better dynamics and slam is probably due to your speaker presenting an easier load to the amp. Tube amps really come into their own when they drive speakers with benign impedance curves and good sensitivity. The difference between a well match tube amp/speaker setup vs. a not so good match is startling.

Regards
Paul
More to discover