Step Up Transformers….Are they Worth the Trouble?

@mdalton 

Any early impressions on HM-7 vs Rothwell? 

With all else being equal (which it almost never is), core size can definitely have an impact on performance. Good luck getting an actual core weight sans all the casing, potting, etc.

EAR MC-3 and MC-4 add weighting to the box so stiff audiophile cables don’t wrestle it around - which is really nice. Almost all the CineMag MC variants use the same size can - but interestingly Quadratic (MC-1) has their CineMags custom made with at least double the usual height (presumably with a proportionally larger core). It featured stronger than usual bass response, along with a slightly relaxed treble (this behavior was consistent across MM stages and cartridges).

Lundahls (9206, 9226, 1931) use amorphous cobalt cores, rather than laminations, which must weigh differently - and I also wonder if this core material explains my aversion to them.

@lalitk 

am on road for couple days so only got one lp side in.  Way more dynamic, without losing koetsu magic.  So very good initial impression.  However, have a noise issue (hum at high volume no music).  pretty sure it came at 1:30 ratio, 29 db gain, which is too much.  Think In gonna have to pop it open and change setting to 1:15 ratio, 23 db gain.  Waiting to hear from Constantin who reached out to Swissonor to make sure that’s how it was shipped before I open it up.  

@mdalton 

Cool!! From my perspective, SUTs actually increase the Koetsu magic. But that hum is not "normal", even at the 30x / 29dB setting, and even with the volume turned up loud (my preferred setting lol). As least, it should not be invasive from your seating position. Anyways 30x SUT's like the Hashimoto will perform well with the 0.3mV Koetsu Platinums, though it's pretty "hot" at that setting. 15x - 20x is ideal. For your Urushi, 30x is way too hot. The 15x setting is ideal for you!

There will be ample opportunities to correct the hum - through various grounding schemes, IC swaps, and making sure all connectors & jacks are tight. Hopefully that can be resolved easily. 

@dover  : Of course that the transformers are a fraction of those kg..The realsubject of my post is its  wide frequency range. I still own that AU-1000 hard wired by me from the transformers to output connectorsandmeasured from around 3hz to over 300khz.

The Denon unit transformers are just " incredible " with no developed hum/noise and way low THD.

No one of the SUTs owned by the gentlemans that posted here comes near to the quality Denon performance even almost no one are flat in such wide frequency range that's unique and in benefit of MUSIC reproduction..

Several audiophiles on this " SUT's party " have any idea what I'm talking about when theyare so happy with those SUT they own that does not permits that the cartridge can shows at its best.

R.