Step uo transformers

[Graeme]

I may be taking the plunge into MC carts.

Im going to need some kind of step up, i assume transformers are the best option?


Not really paid much attention before, but looking around there seems to be quite a choice.

Lookign at sowters website it seems there isnt really a universal choice.

I know ill need 1-10 ratio but what about matching the carts impedance?

How important is this?
Can i choose something in the middle to widen the choice of future carts or would this restrict sound quality too much?

Main cart choices at the moment are either a Rega apheta or a modded denon 103.

The rega cart is probably more likely.

I have been offered a loan of an apheta from work but i have no step ups to try it with. This means i may end up buying the transformers first, otherwise i'd just work out which Tx's suit best.

So, to cut a long story short, is there a 'universal SUT' option or do i realy need to buy some that suit the cart?





Or, should i go with a head amp?

Thanks.

[pre65]

Hi Graeme.

I can loan you my Denon AU-300LC step up transformer if you want to try a MC.

It was designed to go with a Denon 103 and DTB had it on loan for a while so we know it works OK with that cartridge.

[Graeme]

I may take you up on that, thanks.


As your denon sut is obviously designed for denon carts, would its apparant mis match with the rega cart cloud my ability to judge the rega cart?

This is the thing, if one tx would be good for both the rega and the denon then i'd just buy that one.

[pre65]

Well look at it another way.

What step up ratio do you need for the Rega cartridge ?

[Graeme]

1:10, so good there, but output impedance is 15 v's the denons 30 (or is it 40).

This is the bit im struggling with.

Different tx's recomended depending on the carts output impedance.

How much difference does that bit make?

[pre65]

Mind you, the Apheta does cost nearly 10 times as much as a 103, but with your staff discount it may be a bit less ?

Just think, if you borrow one and you like it a lot, can you afford to buy it ?

Or, is the rest of the system up to the same standard ?

[cressy]

ive used the same sowters with all the mc carts ive had. coral 777ex, want another one but theyre like rocking horse poo, benz mc20, denon 103 and 103r and the ortofon sl15. ive never been able to 'hear' them tbh and have not done anything re impedance matching or owt. i dont think it'll make any difference to the enjoyment of the cart, or hinder your ability to listen critically to it. however there are gains to be made by changing the loading. a few owstons ago when i brought my lenco it was put on the end of simons phono that had a selector for the loading. upping the load from 47k to 100k (i think) had the coral singing a little sweeter. it wasnt a huge change, but it was appreciable.

id say borrow phils denons and have a listen. i doubt you'll be able to tell, unless you hear the cart with a different set, i.e cinemags or sowters. i particularly like llundahls but i cant afford them

[Graeme]

Thanks cressy, i figured it was more about perfectly optimising rather than a critical detail.

As for the apheta, yes, i get a very good discount. I can also have it made with reject parts with little scuffs for even more discount.

Option 2 is 103 with an expert stylus cantilever and paratrace, both should work out to about the same price to me i think.

I think my system is up to an apheta in quality, just not in price

Modded lenco in slate
Terminator tangential air arm clone
Upgradec WD phono III clone
Modded WD kel84
Tannoy dual concentrics.

At the moment i think my goldring 1012 is the weak link.

Silly question maybe, but the denon SU's, are they 'unloaded' or do they have an amount of built in loading, as they are a complete unit rather than just transformers?

Apheta needs loading at around 100 ohm i believe.

[pre65]

I don't think the AU-300LC has any "load" as such they "are just transformers". There is a way to calculate how the cartridge will "see" the load of your existing phono stage through the step ups but it's beyond me.

Perhaps Andrew L (or another phono expert) can come in on this question ?

[Mike H]

Is the 1:10 step-up a Voltage ratio or an impedance ratio?


As Phil says doesn't matter a whole lot what "impedance" a transformer is, mostly depends what load you put on the output end.

 

[Graeme]

Great, thanks.

Ill have another word with 'the man that can' next week and see if its still ok to borrow one.


Hope i dont break it