SUT - electrical theory and practical experience

… , L+R Channel Gain,…

@pindac is a gain imbalance common in cartridges?

(I have a cart with some channel imbalance, hence the question.)

I am not educated enough to answer your question, these are the types of question I would take direct to my Third Party Cartridge Service I depend on.

Third Party Cartridge Services from what I have discovered through investigation and discussion with the Technicians does suggest there is a Channel Imbalance being checked and corrected as part of the Serice on offer.

There are Third Party Services who are happy to show evidence of their work, and some will put out photos of the Readings that are being achieved as part of the refurbishment work.

 My reasoning for the purchasing a Phonostage with a L+R Channel Gain Control, is to do with my totally trusting the Designer /Engineer and accepting the options incorporated into the device to deliver as per the designer's intent.

Additionally, as I am usually working with Dual Mono Volume Controls in the Pre- Amp's used and will one day soon have a my New Design Balanced / Single Ended Pre-Amp' Built, to be used with the Modified Power Amp's, which will have a Balanced / Single Ended Input, the option to tweak a loading on a Channel was to me a worthwhile tool, as the conversion to a Balanced Signal Path as the additional option has been projected for a very long time. 

I am avoiding the subject of Phon's and Balanced Signal Paths at present. 

Anyone who have tried a SUT with the Aesthetix Io?

@rauliruegas 

Btw, @intactaudio  : you capacitance parameter of 80pf coukld be not real to make SUT measurements as the 300k load.

as stated in the text you pulled the above numbers from, those are the actual values of the referenced phono stage cable combo not some "made up numbers" 

Normally what sees the MM stage + SUT is a load of 47k and capacitance around 200pf. Then measures arwe different that with your " choosed " parameters.

Again this is covered in the text referenced by @antinn on the first page.  It is indeed true that 47kΩ || 200pf may be a typical number, it simply represents a situation that has a good chance of being less than ideal for use with a SUT.  Gaining a fundamental understanding of the tradeoffs of the cart /SUT/phono interface goes a long way in furthering the trend of commonly occurring mistakes that historically has given SUT usage a bad rap.

Unfortuntaelly cable manafucterer almost never gives the cable capacitance but almost all are higher than 150pf and even over 200pf.

then you need a basic understanding on how load capacitance adversely effects a SUT and you also need to find a new cable manufacturer.

dave

To the notion that cartridges are “natural” current generators I would say that the general statement can only be applied to LOMC cartridges with very low internal R in relation to V output. I would also note that in a “trans impedance” stage , the first stage converts current to voltage. Thereafter and in the RIAA filter, the signal is handled as a voltage exactly as in a conventional phono stage.