Step-up Transformer, what's lost?


Hello all:

I'm currently on my third phono-pre, and I still don't have enough volume! My cartridge is a low output MC (0.23mv), so, by the time I get the volume to my listening level, I get a hiss from the tubes, or a scratch from solid state during the quiet passages of music.

I'm thinking about adding a step-up transformer but I'm afraid of losing detail.

What is the collectives' experience with the trade-off when adding a transformer?
consttraveler
G m c,
most of the times, the step up just does the trick being passive voltage amplification device connected to the minimal amplification circuit having less length of a higher gauge wire than it would be in the cartridge coil with the high output and moreover matching impedance with no additional adjustement to the load section of the phono.
MM phono-stage(especially stand-alone) coupled with step-up transformer can do about the same trick as it would the whole MC phono but and again but depending on the quality of the transformer which might be even more sophisticated to build than an electronic stage. Currently if the author uses MM version of Herron I believe that the cartridge is not properly loaded as well.
Dynavector as far as I know also produces step-up tranny with built-in set of wires. Ortofon T1000 has built-in set of wires as well. If you will order brand-new Quicksilver you can also request built-in set of wires thus you will avoid extra connection.
Marakanetz, i understand what you and TWL are saying, but in my mind, (following the mantra of Keith Herron (Why am i thinking of Kieth Herring?)), more interconnects, more connections, more wobbles, are not good. Is less better? I would sell the mm, and buy an mc, let the connections be solder, silver solder, I hope, and eliminate variables.
Thanks' to everyone for their responses. In answer to some of the questions from above:

Yes, I am using the Herron MC Phono-pre. I had it set-up at the factory to match the recommended loading of the Karat cart. at 100 Ohms. In discussions with Kieth Herron regarding my wish for more volume, he suggested I clip the leads to the resistors which gave me about 6db and un-loaded the cart. Truthfully, the volume is very close to being acceptable now, but I prefered the sound with the cart. loaded. The mids and highs lost some extension and sweetness, solo strings do not have the immediacy they had.

My Pre-amp is a Mark Levinson 380S, which if I remember correctly, adds about 17db gain. My digital front end plays at a reading of 55 to 58db on the 380S, my Rega P-25 through the Herron, plays at 65 to 68db on the 380S, to get the same perceived volume and detail. Unfortunately, I start getting noticable background noise from the Herron at a reading of 60db (lower starting point and louder noise from the Coph Nia and Rega Fono). From that, I have concluded that I need a boost of at least 10db.

Yes, I am using balanced interconnects between the 380S and my amp, and the P-25 is isolated. FWIW, I get no background noise from the digital front end (Levinson 37 Transport and Chord DAC 64) when played at any level.

From the responses above (and I really appreciate your help!) it looks like my choices are 1) get a good transformer at +$1K; 2) get a higher out-put cart for the same or more $'s; or 3) re-solder the resistors and live with the noise (least acceptable alternative).

Thanks for everything, David.
Make sure phono preamp and preamp are physically
separated from one another. This will lower noise floor.
The problem with most step up transformers is the the bass gets softer. And in my experience, a low output moving coil is better sounding than most high output models. It is best to get a preamp that has enough gain in the phono stage or get a line level preamp and get a stand alone phono stage that will have enough gain for low output cartridges. The Reference Phono that Audio Research makes uses a Jensen step up transformer to have enough gain with low output coils. While I have not heard this preamp, and Jensen makes some of the best transformers available, I feel that they are charging a lot of money for something that only costs a few hundred dollars and anyone can order from Jensen on their website. I realize that the transformer is not the only thing about this preamp and that it is highly regarded.