Low output from B&O RX2 2/ SMMC4 Cartridge

Hello all,

Quick question:

But background first, I recently picked up an RX2 and a new SMMC4 cartridge. Everything has been tuned up and hooked up and plays. I'm using the phono stage built into my modern Onkyo receiver rather than a separate pre-amp, and that is my preference for simplicities sake (for others in the home who may be using it). The one issue that I have is the output. When I turn the volume to Max on the receiver, the output is what I would call "mildly moderate." It is by no means loud and there's a lot of room before it would become "unreasonably loud" or even just "loud."

I assume that this is because the cartridge output is ~ 2.2mV and the receiver is expecting something closer to that of an MC level around 5mV. 

My question: Would an MC to MM set up transformer be my best course to bring the level up? I ask because I'm seeing that the suts look like they're expecting a lower input than something around 2.2mV.

Any thoughts?

You shouldn't be having gain problems with 2.2mV output. Not if everything you said is correct. If the receiver has switchable MC/MM input though, and its on MM instead of MC, that would certainly do it.
Unfortunately, it is not switchable... Looking at the input sensitivity spec on the receiver it states:

3.5 mV/47 kΩ (PHONO MM)

If I were to make an assumption that this could explain the lower output that I'm experiencing, would I be barking up a completely wrong tree?
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Okay wait, sorry, it is MM after all? Which is what I was afraid of. Only worse, not switchable. So you have a gain problem. May need to get that outboard phono stage after all. Either that or a new MM cart. Don't even think about SUT, the headaches and cost are seriously not worth it.
Fair enough. Unfortunately, a MM cartridge is not an option with the RX2. The SMMC carts are the only choice.

I was hoping to avoid it, but it sounds like the external phono stage is my only option if I want to go above a "mildly moderate" level, which I'd like the option to do so.

Thanks for your help.
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Thank you for the response. It's certainly as detailed as I could ask for.

Had this have been a choice between a built in stage on the turntable itself, I'd definitely have been using a discrete preamp already, but I was trying to go with that of the receiver because it is likely "good enough".  My records are more "kids recording on a shoestring budget" and less audiophile pressing of Dark Side of the Moon, so they can only sound so good. And as I said above, simplicity for the sake of others was desired, if I could go that way.

The more I've looked at things, the more I've seen that you are completely right. I've been looking at the Schiit Mani as a "this will work for now" solution that I can try out and maybe find that it will work long term. It's certainly cheap enough to take a flyer on.

Thanks to everyone for taking the time,
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Thanks, I will.

To satisfy my own curiosity (and as a strictly academic sort of question), I've looked up the formula for calculating gain required to bring a signal up to a specific level. That brought me to one question:

To determine the level that I'd be shooting for, would I be looking at the line input sensitivity of the equipment I will be hooking the pre-amp up to?