What MC step ups and head amps has anyone tried, and what differences did they hear? I have 4 transformers and 3 head amps now, doing comparisons, and ulimately confusing myself about which I like best.
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What MC step ups and head amps has anyone tried, and what differences did they hear? I have 4 transformers and 3 head amps now, doing comparisons, and ulimately confusing myself about which I like best.
Could you tell us which preamps (and the rest of your amplifying chain) you have? And, of course which cartridge!
John
Guys,
This is a subject dear to my heart - I'll get to it later! :)
Marco.
Mayware 'T24' Transformer which uses a technique called 'reflected shunt equalisation' which uses a low inductance transformer enabling the use of carts from 2-40 Ohm.Has user changeable tappings ( Not really a good thing, but!)This was one of my best trannies regardless..
gain varies from 30dB for 2/3 Ohm to 20dB for 40 Ohm carts..I did use this with the Mayware 'MC-7V' cart to superb effect.Superb dynamics also.Just another one of my past exploits...Funny how we de-grade as we up-grade!
I'm developing an odd fascination with MC impedance matching transformers. This is particularly strange as the cartridge I use (Audionote Io) dictates the use of a very high ratio (100:1) transformer and the only people to make such a device are Audionote or Kondo. I found some loose transformers from the old silver wired Audionote Japan S6 on ebay which I put into a box and which suit that cartridge perfectly. Kondo still makes a version of this called the SFz (v. expensive) as do ANUK with several models.
ANS6
http://i75.photobucket.com/albums/i3...son/16_3-1.jpg
Internal View
http://i75.photobucket.com/albums/i3...son/0d_3-1.jpg
Loose transformers
http://i75.photobucket.com/albums/i3...son/5c_1_b.jpg
So why the interest in others?
There were many different manufacturers of high quality studio equipment in the 50's and 60's. Most of these produced (or had produced) microphone matching transformers which facilitated the use of low impedance microphones with high impedance inputs. People have realised that these are applicable to use with MC cartridges and the prices of these loose transformers is creeping up. Models such as those by Altec, peerless, Jensen, RCA, UTC, Dukane all offer outstanding performance and are relatively simple to wire into a chassis. I recently bought a pair of Dukane 3A25's for a few pounds. These gave glorious results with an AT OC9 that I'd never previously wanted to listen to for more than a few minutes at a time.
Dukanes
http://i75.photobucket.com/albums/i3...n/P1010215.jpg
A friend has some UTC A10's and has just bought a pair of the danish Jorgen Schou transformers which I'm keen to hear. It seems that the core materials used in the laminations as well as the winding techniques used (particularly in some of these older designs) can really preserve an incredible depth of tone from an MC cartridge in a way that wouldn't have seemed possible based on listening to the cartridge under normal circumstances.
Have a look here for more inspiration
http://members.myactv.net/~je2a3/mic-mcstep-up.htm
Keep an eye out for auctions like this.
http://cgi.ebay.co.uk/ws/eBayISAPI.d...MEWA:IT&ih=018
From the Pure Sound point of view, I've found a European supplier of a goodish quality 1:15 transformer which would certainly do for most newcomers to the joys of MC's and which would go well with our phono stage.
I've also found a UK transformer supplier who can make me some custom wound 'specials' with fancy core material and winding arrangements. The only problem with these is the outlay involved and the fact that they would cost half as much again as the phono stage we make! For me its not a problem as I appreciate the difference a good transformer can make but whether there's really much of a market for a £600-700 transformer remains to be seen.
If there's a good set up with a (mostly expensive) MC cartridge that price is not a problem. A problem though is the quality of the transformer, the shielding and the room it takes. In the past a transformer had the advantage, over tube and transistor amps, of a low noise level. But that time is past! Nowadays it's easy to construct a MC preamp with a noise level of -75 dB at 0,3 mV//100 Ohm.
John
Dear Vinyllist
Nothing is perfect. And every configurattion has it's advantages and disadvantages. So there are always some kind of consessions when designing an item.
Now let's have a look at some of the possible (!) qualities of both.
The step-up transformer:
1. It's passive so there's hardly any non-linear distortion
2. Bandwidth is ALWAYS limited
3. A good one is relatively big and needs space
4. It's supsceptible for "fields"
The active solution:
1. Distortion can be very low, around <0,01%
2. Bandwidth is wider then any vinyl record holds
3. If the "lay out of the PCB" is okay no shielding is needed
4. It needs a power supply and that supply should not be coupled with the RIAA pre-amp thereafter.
In the end it all comes at a price. A good MC step-up transformer will cost >1500 € and an active MC pre-amp, including RIAA, comes at around the same price. At present we offer a complete pre-amp kit, without the cabinet, for 895 €.
John
A precisely matched high grade step up transformer is far superior to any MC stage. Fact!
I can see your trying to sell your products, but please put that aside..