MC Step-up transformers

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Do you like the idea of winding 1-2 km magnetic wire 1/4 the size of a human hair 3000 turns on a three chamber bobbin with a few pct tolerance on a core made of a couple dozen paper-thin layers? At least that's how Telefunken used to do it. That's on the extreme end. Most are not made that way.

With good to great step-up transformer around for about $100, you probably have to want to make your own for it to make much sense.
 
There always seems to be some Peerless 4722 on eBay.

Haufe transformers turn up fairly regularly. T42 has a step-up ratio of 1:20, T41 1:10. My guess is that they come from old Klangfilm gear. They were used as input/balancing transformers.

All tend to bring around $100/pair. More if they are boxed or mounted.

I believe Shindo and Auditorium 23 source their transformers from Haufe. The legendary, and ridiculously high-price, Neumann BV-33 was probably sourced from Haufe as well.
 
Mc transformers for less than 500 dollars? How about Lundahls? They have several different winding ratios available

LL1678 1+1+1+1 : 16+16 Moving coil input. Amorphous core. about 60$ each.
LL1681 1+1 : 13+13 Moving coil input. Mu metal core. about 85$/each.
LL9206 1+1+1+1 : 10+10 Moving coil input. Amorphous core. about 60$/each.

I will shortly be using the LL1578 (not the 1578XL, I don't know if the XL will work as an mc stepup trans). The 1578 is listed as a microphone input transformer, but can be used as an mc stepup too. 1:10 or 1:5 ratios is possible. I got lucky, was offered a non-RoHS pair for less money, didn't hesitate.
All of these are probably very good. Prices for these are in dollars as I found them on http://kandkaudio.com/. http://www.lundahl.se/ is the manufacturer web site.

Or how about the Sowters?
8055 Studio Phono 1:10, "fully balanced", about 57 pounds/each
9575 1:20 Low Z, about 49 pounds/each
9570 1:10 Low Z, about 49 pounds/each
9580 1:12.5 High Z. about 49 pounds/each
All of these are also probably very good. Prices for them are in Sterling Pounds as I found them on http://www.sowter.co.uk.
 
I don't know if I’m barking up the wrong tree here, but I've seen microphone transformers with reasonably good specs starting at about $10 and up.

I can only assume the more you pay for a transformer, the better it should be but these low budget items have got me thinking they might be able to substitute the less expensive MC step-up items.

Would I be wasting my time if I was to go out and purchase a pair of CP8201 microphone transformers .
 
I'm not sure low-price mic transformers have good enough frequency response. I any event, step-up transformers need not be expensive.

The common Beyer mic transformers are probably the best budget step-up transformer out there. You can get pairs for under under €25 on eBay. http://cgi.ebay.com/Beyer-Dynamic-V...ryZ15198QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

As long as you stay away from the likes of WE, UTC and Telefunken, transformers tend to be fairly cheap. The "legendary" Neumann BV-33 sells for around €1,000. That's for a single! I'm pretty sure it was sourced from Haufe. The same transformer without the Neumann logo costs around €50-100. Same thing with the WE 618B. I believe the Langevin 402B is identical. Price: €1,000 or €50-100.

I did some quick shopping and found these:
http://cgi.ebay.com/VINTAGE-BOGEN-T...1QQihZ013QQcategoryZ67815QQrdZ1QQcmdZViewItem

http://cgi.ebay.com/TEN-VINTAGE-INP...1QQihZ017QQcategoryZ67815QQrdZ1QQcmdZViewItem

http://cgi.ebay.com/Two-15095A-Alte...3QQihZ019QQcategoryZ67815QQrdZ1QQcmdZViewItem
 
I've got a pair of Jensen MC step-ups in an extruded sescom case that I'm not using (I sold my turntable). I'd be willing to sell or trade them. they are the 44K-DX units (http://www.jensentransformers.com/datashts/44kdx.pdf) They are a 10:1 step-up for low impedance cartridges.

I've got some pictures of them in the case here:

http://casastokes.dyndns.org/photoalbums/index.php?album=/Audio/MC_Stepup

I have tied up the wires rather than cutting them, aside from the fraction of an inch used to solder the wires to the connectors, they are stock length.

They cost about $100 each new. Got anything to trade?


Sheldon
 
phn said:
I'm not sure low-price mic transformers have good enough frequency response. I any event, step-up transformers need not be expensive.

The common Beyer mic transformers are probably the best budget step-up transformer out there. You can get pairs for under under €25 on eBay. http://cgi.ebay.com/Beyer-Dynamic-V...ryZ15198QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Here's a interesting link (read) on the use of microphone transformers used as MC step-up transformers. Moving Coil step-up transformers
 
what about 1:1 to 1:2 loading of a 47k/~5mv unit? anyone ever tried it? Why? Yah never know till yas dunned it. Ie, I'll never rule it out unless I hear something that sounds definitive. Pun intended.

Might help those POS high inductance units finally sound OK for once. (It might be noticable at this point..that I'm a super low output MC fan, or rather, super low number of turns would be better way to say it)
 
MC Stepup Transformers

Hi All

I have a Supex SDT 1000 'booster for MC cartridge'. Nicely made. Looks like some h/q Tiffany rca's at the back + earth terminal and in front an on/off saying "boost/off".

The device is nicely made with an alu faceplate and an outer fluted rubber jacket which one can slip off. The casework under the rubber is completely soldered closed and goldplated.

And the darn thing hums. Not seriously, but it's there. If the armlead is unclipped from the stepup's earth tag, it sounds like a wannabe Moto Guzzi. Fortunately I have other stepup devices.

@Sy: Nice new avatar, my man :D Could it be Brutus:cannotbe:

bulgin
 
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