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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?

Thanks,
Andy
andymckay
9 responses Add your response
andymckay OP
10 posts
 
viridian,

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?
Post removed 
andymckay OP
10 posts
 
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,
Andy
Post removed 
andymckay OP
10 posts
 
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.
millercarbon's avatar
millercarbon
12,531 posts
 
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.
Post removed 
andymckay OP
10 posts
 
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?
millercarbon's avatar
millercarbon
12,531 posts
 
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.
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