EI Vs Toroidal

The toroidal in my F5 clone hums surprisingly loudly. Virtually no noise at all through the speakers, but you can hear that toroidal humming away from 2 or 3 feet away. It almost makes a grunting sound when I power it up.

Toroids saturate easily if there is DC on the AC line. A common cause of this might be a heater running at half power- it is only drawing power on one half of the AC waveform. This causes half of the waveform to have a lower amplitude- and thus can be regarded as DC on the AC line.

Its easy to block with a simple device, and may silence the transformer. The amp might also sound better too, as the transformer might then deliver a cleaner waveform to the power rectifiers.

The grunt at turn-on is common with many transformers, toroidal or EI core.

Huh, I had always thought that Toroidals made the best transformers.  Then a newer company called Schiit(of which I've become a fan after trying one of their DACs) released a 100 x 2 wpc amp featuring an IE transformer, stating that they prefer that over the toroidal design.  

I was surprised, but apparently that little amp holds its own.  Now I read this thread, and realize that the science isn't as settled as I thought!

Silk Transformers-anyone used them?

Ptss - yes, I looked into the Equitech product line a while back while researching the benefits of various power conditioning approaches and read most of the web site info back then.

Scaling up a transformer design to the power levels at which their products operate, significantly increases the mechanical noise factor and the footprint. So for their products, toroids are an excellent choice.

Even though some electrical efficiencies are also achieved, I believe noise and size are the main issues that are easily overcome by the use of toroids.

It’s not so much that one design is clearly better than another, but more of a choice as to what the designer is "prepared to live with" and what steps they are prepared to take to address the shortcomings of a particular transformer type

Except - in those rare cases where the designer pulls out all the stops and designs the transformer of their choice to provide the very best performance.

Two companies that I believe excels in power supply design are...
- NAIM - mostly use toroids for their power supplies
- Macintosh - mostly use EI for their power supplies (or used to)

Also, there are still some "uses" where EI has been the preferred type for a very long time, such as amplifier output transformers.

From what I have read, it appears that where the entire audible frequency range must be handled, as opposed to the 50-60 hz of the mains supply, EI appears to be better suited. But that may be changing as toroid (and other designs) progress.

Personally - I do not allow the minor differences between the various types to sway me.

My approach - If a component sounds exceptional, then the designer has achieved their goal - regardless of transformer type.

With the "quality" of component I now find myself purchasing, I have to believe the designer has already obsessed enough over their selection - that’s good enough for me :-)

From a DIY
Regards.

I read the article. The EQUITECH website provides information you may enjoy reading. Allow time for a through investigation. Your thoughts?

To clarify....

except for the slightly louder hum when using the EI transformer.

This was actually a physical hum from the transformer vibrating on the shelf and not anything electrical that was propagated through the system

Cheers

Infection, whilst the quality of the trasformer is key, I believe the type tends to be somewhat imaterial.

The proliferation of toroids in today’s components probably has more to do with slim case designs, but also their lower audible hum levels makes them more desirable to component designers.

I have two source components, one with EI and one with toroid and believe there is little difference in their perfomance that can be attributed to the transformer type.

The component with the EI transformer is very quiet, i.e. no hum, an indication of good EI transformer design/build practices.

In the past, I have replaced the wal-wart AC "power supply" with an EI transformer and later with a toroid. What I discvered is, there was no audible difference in the performance of the component , except for the slightly louder hum when using the EI transformer.

I believe the key really is the quality of the transformer design and build, which is difficult to discern from a simple visual inspection of a component.

Having said all of that, the artile indicates EI to be superior, however, I would not allow that to guide any decision I might make about a component based on the transformer type alone.

I let my ears do the listening 😊

Hope that helps