Why are better transformers better?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by NoahL, Jan 30, 2008.

  1. NoahL

    NoahL Member

    Messages:
    1,423
    Joined:
    Jan 19, 2007
    I've read about how the transformer is key to amp tone and how an upgrade to an expensive one can make a difference. What is inherent in the materials and design and build of the expensive boutique transformers that makes them so much better? Here's why I ask. I was installing a second chime for my doorbells, and so I needed a more powerful transformer. Hardware store only had the 12v cheapies, when I realized I had a 24v behemoth in my garage that I'd bought when I tried to fix an old boiler. This is a $130 transformer, which the supply store wouldn't take back, even though it had been wired in for five minutes and metered out at a healthy 25.8v. Now it's powering my doorbells, and they sound great! (LOL). I haven't listened closely (how hi-fi is a door chime anyway), but they sure do ring. Maybe it's the extra 1.8v -- maybe my whole house is about to burn up, who knows? But it made me wonder -- what's in that $130 transformer that isn't in the $15 special from Ace? Clearly the expensive one is heftier than the Ace one would be, despite their similar voltage ratings...
     
  2. jscorno

    jscorno Member

    Messages:
    149
    Joined:
    Feb 19, 2007
    Location:
    MA
    I've think you've answered one this yourself: it's louder isn't it?

    :)
     
  3. NoahL

    NoahL Member

    Messages:
    1,423
    Joined:
    Jan 19, 2007
    It certainly is, but I wasn't sure if it's just because it's 25.8v into two chimes and not an old cheap 12v into one. I was also assuming there are tonal qualities that expensive transformers provide -- but how? Thanks for responding -- I'm not saying you're not right ...
     
  4. wladok

    wladok Member

    Messages:
    20
    Joined:
    Oct 3, 2007
    The doorbell is probably just an actual bell being hit by some sort of electrically driven actuator... like a solenoid. Driving it with more power increases the volume of the doorbell by hitting it harder.

    But a tube amp is much more complicated. The tone comes from the way the circuit components (including the transformer) interact with each other and respond to your playing....... In this case its not as simple just the voltage of the transformer... it also depends on the frequency dependence of the transformers electrical properties. This depends on the type of magnet, wire material, wire thickness, number of wraps, etc...

    I'm not an amp builder, so I have never tried switching out different transformers, but I can imagine it might make quite a big difference.
     
  5. Adwex

    Adwex Member

    Messages:
    520
    Joined:
    Jun 15, 2007
    Location:
    Long Island, NY
    Apples and oranges...I think. In a guitar amplifier, the audio signal that eventually makes it's way to the speakers is actually travelling through the output transformer. I don't think the audio you hear from your doorbell is going through the coils of the transformer.

    Also, a larger transformer is probably capable of carrying more current than a smaller one, for a given voltage change.

    I'm also curious how the output transformer in a guitar amp can affect the tone.
     
  6. NoahL

    NoahL Member

    Messages:
    1,423
    Joined:
    Jan 19, 2007
    I hear ya. The doorbell bit just put the question in my head, when I wondered what makes one 24v transformer cost $130 and another $15 ...
     
  7. donnyjaguar

    donnyjaguar Member

    Messages:
    4,244
    Joined:
    Nov 4, 2005
    Location:
    Canada
    I've definitely answered this question on this forum. Do a search.
     
  8. rooster

    rooster Member

    Messages:
    2,123
    Joined:
    Mar 9, 2005
    Location:
    Arizona
    Better transformers are better because they're better.

    Feel better?

    rooster.
     
  9. PRNDL

    PRNDL Member

    Messages:
    502
    Joined:
    Aug 25, 2007
    Location:
    SW Florida
    Transformer pricing is usually based on the following:
    - iron and wire: often the most expensive
    - circuit complexity: SE vs PP, ultralinear, number of taps
    - frequency response

    For more power (current) you need thicker wire and more iron, which increases the base cost.

    HiFi transformers are usually very complex and have much broader frequency requirements than guitar, hence their high price.

    As for the $130-25V vs. $12-12V, driving an audio opamp (or transistors) with higher DC voltages results in increased headroom and volume. IC chips, however, may suffer.
     
  10. rooster

    rooster Member

    Messages:
    2,123
    Joined:
    Mar 9, 2005
    Location:
    Arizona
    More "bet" = better.

    rooster.
     
  11. Nolatone Ampworks

    Nolatone Ampworks Silver Supporting Member

    Messages:
    2,736
    Joined:
    Jun 4, 2006
    Location:
    Flowery Branch, GA
    The brings up another question:

    We usually refer to output transformers in this sort of discussion.

    Does any of this apply to power xfrmrs? Provided the PT supplies the needed voltages in abundance, is there anything to gain by upgraded the PT?
     
  12. Rod

    Rod Tone is Paramount Silver Supporting Member

    Messages:
    16,612
    Joined:
    Nov 29, 2004
    Location:
    Santa Fe New Mexico/Kittery Maine
    Better doesn't always sound better...Case in point...One of my amp builder friends here..[who's a genius]....was asked to order and install a pair of Mercury Magnetics output and power transformers into an old Fender Tweed Pro 1/15...that sounded fine stock.....Well, some $400 later with the new transformers, the amp didn't sound as good as it did stock.....
     
  13. jay42

    jay42 Member

    Messages:
    6,800
    Joined:
    Dec 20, 2006
    Location:
    Sandy Eggo
    There's always that risk...beauty in the eyes...or ears of the beholder. I've replaced two OT's in working amps. In both cases I was very happy, but I knew I was rolling the dice. fwiw, I can't see changing a PT in an amp that's fine. You'd have to have some specific reason, like needing more filament current.
     
  14. Rossl

    Rossl Member

    Messages:
    298
    Joined:
    Nov 2, 2005
    Location:
    Northern NJ
    I agree sometimes better is not better. If you increased the voltages in your amp, it most likely will not sound better, unless you wanted more headroom and a little colder sound.

    It depends what you are trying to do...............you should describe what you have know and what you would like to do.

    BTW, if you chimes are rated for 12v they may fail sooner with the higher voltage
     

Share This Page