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Step Up Transformer Question

Ok, so bear with me as this is new terrain for me. I was quite happy with how things were sounding and then I accidentally bumped the stylus of my Cadenza Black and snapped the cantilever clean off. I did some research and ultimately decided to have Steve at VAS at fix my cartridge but it was going to take a few weeks and there was going to be no way to play the Christmas vinyl that my wife loves so much. She told me to buy another cartridge so we could have Christmas records. I was stunned. I found a great deal on a Winfeld Ti on this site and pulled the trigger. I've got it on my table and it sounds amazing. 

After speaking with Steve though, I'm going to trade in my Cadenza and have him build me a wood body cartridge to have something different. It will also be 0.2mv output. I think I've got the 2nd arm situation sorted (gonna buy a Wand and a pod to mount it on) which leaves the phono pre. I love my Rogers PA-2 and it is switchable between MC and MM with 2 different inputs in the back. Finally got the SUT part. I've been looking and trying to figure things out. I spoke with Roger and he said the transformer built into the PA-2 is 1:10 and with that I can achieve 70 or so dB of gain. I did a lot of reading and looking and while I'm sure a 4k+ SUT is amazing that's just not where I'm at with all the other expenses at the moment. I saw the Bellari MT502 was a stereophole recommended component for many years and Amazon had one on sale for like $349 or something. Figured can't hurt to try it, it's Amazon so I can always return it. I plugged it in with some admittedly questionable interconnects I had lying around and when I put the phono stage k there was a bit more hum than I'm used to but I said let's have a listen. Holy shit. This little thing blew my mind. Better impact, tighter bass, more space around instruments so better staging, improved transients. This puts me in an interesting place. 

This is an extremely inexpensive piece and it has changed my system quite a bit. I think the little extra gain I get even at 1:12 brings the cartridge to life. My question is where do I go from here? Bob's makes the sky 30 which is switchable from 1:15 to 1:30 which I like because I can play with the gain tubes in my preamp and potentially go to a quieter 12au7 than the 12ax7 that's currently in there. Will that be a real improvement? Less hum? Had also considered ordering a Rothwell from jolly old England but can't find much on them. Thoughts? I'd like to keep this sub 1k or so for now. Maybe I'll save up for a big boy SUT later. 

rmdmoore
terry9
2,333 posts
 

There seems to be a lot of markup in some SUT's. Why not buy bare transformers and put them in a box yourself? More control, more satisfaction, less money.

Sowter makes good ones. Lundahl makes several grades from good to great. I've used both. The Lundahl 1931Ag is quite unforgiving. Why not email Lundahl and ask? They are very nice people, and helpful too. So with Sowter.

Good luck!

dogberry
647 posts
 

And it might not matter if we carefully calculate the effective loading on the cartridge:

 

At the end of it all, if it sounds pleasing to you, it is good and you might as well be happy.

terry9
2,333 posts
 

Another thing - the higher the gain, the higher the distortion. Just something to keep in mind; don't buy more than you need.

lewm
13,021 posts
 

Dogberry, The information contained in the referenced thread from Steve Hoffman Forum echoes precisely what Atma-sphere and Jonathan Carr (two authoritative sources) have been writing on this forum for years, loading an MC (at any resistive value above some multiple of 10 or greater of the iinternal R of the cartridge) should make very little to no difference in frequency response. Yet, there are an endless number of posts stating otherwise. I suggest to anyone interested in this topic to search these archives for their words. Even below a load equal to 10X the internal R of the cartridge, where you start to get significant loss of gain, due to shunting of the cartridge output to ground, the gain penalty is very gradual as you go down from 10X to 1X (cartridge internal R = load R), where 50% is lost to ground but also there is a potential loss of HF response due to capacitance at the interface, and almost all phono stages have at least some input capacitance.  The input Z does affect the phono stage in ways described by Atma-sphere.

pindac's avatar
pindac
2,864 posts
 

@dogberry In a earlier post on in this thread, I make it known how impressive the Sculpture A SUT has been as a Copper Winding and produced as an ideal match for a 0.2mv Cart'.

In the same session a Silver Winding SUT from Sculpture A that was not the ideal match, was also used on the same 0.2mv Cart', which proved to be equally impressive for different reasons for how it produced a sonic.

From all of my experiences had using SUT's, these are the most attractive I have from recollection.

Using ones ears to assess whether the interface is an attraction or not, really does seem to be the method. 

I have had SUT's demo'd that are ideal matches for the Cart' in use, where there is noticeable overbearing perception of Bass Weight being produced, as well as a unattractive Looseness of the Bass Notes. Certainly not my flavour of choice.

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