Miam...
Better subjectively to both of us than the amorphous Lundahl we used in the first one. No one gave its nominal ratio when 47k loaded mind you. Could give about 9.5X when measured with the DVM (very high impedance) but dropped 30-40% in real use. When the naked input gave 43dB exactly as modelled when I measured it, the SUT got it up to 58dB total. It also rose THD significantly when we downloaded it at 18K. So we went to 47K as recommended in spec.
Further news are that the Itch also played very successfully a Sumiko Blackbird HiMC, of course without the SUT. No other changes were felt to be necessary.
So you mean the setup ratio is dependent of the load and amplification right ?
I am seriously considering "stepping up" my 48dB riaa with a 10x lundahl for use with a 0.15mV cart but the more I read the more I am convinced this is not an easy process.
I don't know, its a quirk that I did not have time to investigate enough. Maybe its individual to those tube phono matching that I had seen it. I am sure I got less than nominal ratio when in circuit in 3 cases and 2 types. Maybe its because the primary was floating, grid current, can't say as for now. There is also 1:5 and 1:20 configuration option in Lundhal.
Yes.. but it also affects reflect load to the cart.... IMO (as an unexperienced guy in this aspects) it might be quite difficult to match some carts to some TX.
But, wait a minute... if primary is floating and cart was surely not grounded, that is balanced transfer. The secondary sees a single ended circuit that has a signal ground. Mustn't we lose dB if it is magnetically analogous to converting from balanced to SE?
Nothing untoward with the cart and phono in the real system. Went to another system with HiMC, bypassed SUT, no problem reported from there again.
It will not be immune to the circuit, converts to SE. Can help not picking on the TT cabling run until phono I guess.
Only if all impedances to ground are equal. That means a carefully balanced primary winding on the transformer, which is not always the case.
What happens if you put a finger on one of the cartridge pins?
Will see next time I visit the installation. Or will ask. If its balanced good should make no noise? Can I put two equal resistors in the primary and ground the middle point?
DL-103 and Partridge 977 are also in love if 1:6 ratio is sufficient, seems to sound best run straight into 47K, and the best thing is a raw pair will run you less than $80 USD on eBay.uk..
You can, but that "fix" has a limited range and is quite incomplete. If the transformer primary is not well balanced, it's not well balanced, and there's not much you can do externally to fix it.
What is supposed to do when I will touch a cart pin if its well balanced? Will have to wait to know because its still loaned to another HiMC cart system playing without the SUT.