Is a Step-up Transformer needed?


Hi, I am using a Denon DL-103 with an Output Voltage of 0.3mV and a recommended load resistance of 100 Ohms or more except when transformer is provided (direct quote from instruction manual) and a Pro-Ject Tube Box SE which can be set to either 100 Ohm, 220 Ohm or 1kOhm. I am confused about the output voltage issue. Can I use any of these settings without the step-up transformer? Thanks.
128x128tarraga
I used mine with a Bob's Devices Cinemag 3440A SUT into my phono input and it sounded great.  The sound had more authority and detail through the SUT.  I believe the Denon is a 30 or 40 ohm load.
40 ohms load. You should go for a SUT. There is an interesting thread regarding the usage of SUTS or not on Agon.

you have 60 db's of gain with the box.

Use that and you can pay the load by ear, besides the recommended setting.

You may just have to use more of the volume knob for desired 
loudness.

Dear Thuchan, Do you have some general criteria for SUT's use?

Should they be used by all LOMC or is the output not relevant?


Dear Thuchan, Do you have some general criteria for SUT's use?

Should they be used by all LOMC or is the output not relevant?


An SUT (Some call them Head Amps) are needed if your phono stage doesn't have enough gain to deal with a low output cartridge. For example, if you have a phono preamp that supports MM only and you have a LOMC, you would need an SUT because a lot more gain is needed for that type of cart. 


This particular case is interesting because the OP has a phono pre that should support a LOMC, but in reality the lower the voltage, the higher the quality of phono stage is needed for comparable SQ. Especially since his phono pre uses tubes. With a cart output of .3, you're asking a lot from the phono stage. It will be pushed right to its limit. 

In my opinion, its 50/50. Try the Pro Ject first, by itself, and if it sounds OK that's all you need. If you get some noise or distortion, then it would be wise to switch back to MM and use a SUT.