Bobs Device SKY 20 or A23 (Denon) SUT for my Charisma 103 cart


I will be adding a Step Up device to my system soon. It's an Amadeus table, Charisma 103, which has ruby cantilever, but nearly identical specs to a standard Denon 103. These will feed my Croft phono integrated driving Harbeth P3's. I'm leaning toward the SKY 20, but does anyone have any experience here. I'm a little surprised these units haven't been compared anywhere that I can find. Art Dudley did a write up on the Sky, but in the article he made reference only to A23 Homage SUT.  Cheers -Don
fjn04
A bit late to this thread, but I just picked up a Bob's Devices Sky 20 and am thoroughly impressed with it. Quite remarkable how a tiny box like that can produce such a huge increase in resolution - without the usual SUT artifacts like high frequency rolloff, loss of detail or hum. And this is after owning a whole raft of highly-rated Japanese SUTs. There's a lot of hype in this hobby (business?) but Bob's Devices transformers are the real thing.
Hello Don,
can you sling some solder ?
If so, then I would take a look at Dave Slagle at Intact Audio. He can wind the step-up to fit your gain structure, not the other way around.
He is second to none winding transfos. Takes a look at Dudley's review in Stereophile of his Emia unit.
While Dave is a friend, I have no financial stake. I do have a lot of his iron in my projects though, because of the quality of his work.

Cheers,        Crazy Bill
You must live in a parallel universe to mine.  Listening to anything analog be it cartridges, turntables, arms, interconnects, SUTs, you name it is just damn near impossible these days.
I would try to listen to as many SUTs as you can - at shops or via trial periods.  SUTs are very personal preferences IMHO.  Also make sure your SUT is actually 10x, 15x, 20x, etc.  Sometimes they are not. I had to return a Sky30 because of it.  Using a Hashimoto now.

The SKY 20 has 2 settings: 1:10 and 1:20.  The reflected impedance (using a 47k ohms setting on the phono stage) at 1:20 is 118 ohms. At 1:10 it is 470 ohms..... With the exception of the 1:10 and 1:20 adjustable settings, I won't pretend to have my head around the rest. I'm not to worried about it in the case of the SKY, with the Trial period and the fact he has experience with my cartridge. I've heard of the Parks Audio, will definitely check that unit out along with the Audio Interface. This is great... thanks!!

 


I'm  sure works fine and it would depend on your gain structure but in my system I found the higher gain to work a little better and offer some extra dynamics 
analogluvr: I disagree! 1:10 is fine for the 103's. They have an average output of .3mv (x 10 = 3mv). Perfectly adequate for most phono stages!
Parks audio. Same as bobs devices(cinemag) but literally one third the price. And for the 103 I would think you would need 1:15 or 1:20
Save yourself some money and look into the Audio Interface CST 80 SUT. Comes in a 40 Ohm or 1:10 version that is absolutely perfect for the 103. 

I have both the 40 Ohm and 3 Ohm versions and they are by far the best SUT I have ever owned. 


Thanks for the advice so far. Bob (Bobs’ devices) carries my Charisma cartridge, and likes the Sky 20 for it. Then of course, the standard high impedance A23 is for the Denon 103. The MFA does indeed look interesting. The Baby Classic has great flexibility with adjustments, if I were to change my MC in the future. May be overkill for this system however.
Don,

A bit more expensive, but the second best transformer I have heard is from Auditorium 23 at about $1,000. The best being the Hommage

Best Regards,

Jim Perry
I would also consider the MFA 632 ($759) or if you can spring for it the Baby Classic ($1995) -- Jonathan does great work and can design the transformer to suit your specific needs. I have the Classic V2 and really love it -- but my dealer claims the Classic sounds better ...

https://www.stereophile.com/content/listening-172-music-first-audio-mc-step-632-vinyl-cleaner-pro

https://mfaudio.co.uk/mc-step-up-transformers/