Beginnners question - Phono stage


I am kind of new at this hobby and have a dumb question. Why is it that when I listen to my CD player or tuner, the volume control on my amp is usually set at approximately 40 out of 100 and it is plenty loud. However, when I am listening to vinyl on my turntable, I have to crank up the volume control to 70 to get the same sound level out of my system. I have an AR turntable with a MM cartridge. I tried another turntable with a MC cartridge (making sure "MC" was selected on my phono stage) and it was even worst...I had to crank the volume control to 80! My amp is a Pathos Classic One MKII, a Musical Fidelity XRayV3 CD player, Linn Pekin tuner, Totem Hawks and an MF XLPS phono stage. Is this normal or do I have a problem ? Is this possibly linked to the phono stage itself, cabling or simply due to a cartridge/phono stage mismatch ? Thanks for your help.
sympaticonorm
Thanks again for all your help ! I think that I will be learning for quite some time in this hobby...and it is so interesting !
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an inexpensive and decent sounding step up transformer can be ordered from audio cubes for 131 landed; it is the denon AU300LC

www.audiocubes.com

it is not the last word but it does not cost 500 to the sky, either
An excellent online resource for cartridge/phono stage gain compatibility is the preamp gain calculator at

http://www.kabusa.com

Definitely worth checking out.
After letting the XLPS phono stage turned-on for a day, and more listening time, I would say that the MM side of the phono stage is fine as is. My next move is to find the right cartridge for the SME III and see what results I get with my Linn LP12. Thanks for all your help everyone...I really appreciate it !
A good step up transformer will work nicely. I have a K&K step up that uses Lundahl transformers ($250 as a kit, but can come assembled for an additional cost). It is tiny so it is unobtrusive and can be configured for 14db, 20db or 26db of gain. The others mentioned by Nsgarch are good brands as well.
Another solution, barring adjustable gain, and one actually preferred by many highly sophisicated analog audiophiles, would be to use a high quality step-up transformer (Bent, Audio Fidelity, Jentzen) before the phono preamp. I'm sure you can find many threads on the subject here on AgoN.
Generally speaking, you need to look at the output of the cartridge and then look at the gain provided by the phono stage and match them up. You can look here for a guideline:

http://db.audioasylum.com/cgi/m.mpl?forum=vinyl&n=271912&highlight=gain+elison&r=&session=

and my experience leads me to believe that with very low output moving coils (say .3-mV or less) you'd be safe even going another 2-3 db. or so.
You guys on Audiogon are great !! I now have a better understanding of what is going on. The MF XLPS does not have a gain adjustment external or internal. Overall, I am fairly happy with the sound I get from the MM cartridge but I definitely can't use my present MC cartridge (Denon 301) with this setup. Is there a formula or a way to determine best match for a specific cartrige and phono stage. I guess the sensitivity of each is a key element. Or, is the best approach simply to look for a phono stage that has a gain adjustment. I have a Linn LP12 with an SME III tonearm that I want to get operational and certainly would not want to end-up purchasing a cartridge that is not really compatible with my phono stage..nor do I really want to start going thru a trial and error game with phono stages...Thanks again !
I definitively second Photon46, he nailed it right on. Too much gain is often more of a problem. If your amp has an active pre-amp stage, it may actually sound better with the volume turned further up.
You guys nailed it... guess there's no need for me to chime in except to say I would agree with Lugnut and Nsgarch.
Happy Listening!
In addition to what Lugnut said, you might check the owner's manual or with the manufacturer to see if you can make an internal adjustment to increase the gain on your MF XLPS.
Obviously your phono stage doesn't have enough gain to match the high voltage output of a CDP. If you are pleased with the sound and don't have any unacceptable circuitry noise then you are fine. It is common and may not be a problem at all.
Your phono stage multiplies your cartridges' signal a certain fixed amount, so the volume level from your phono input varies according to the output of your cartridge. Most MM cartridges output somewhere between 4 to 6.5/7 mv, so that can account for quite a large variation in where you need to adjust volume. When I went from a Goldring 1042 to a Grado Sonata, I had to turn up the volume quite a bit more. I doubt that you have any cause for concern. Using your volume control @ 70% should be well within it's range of optimal operation. Be more concerned about the opposite problem, too much gain. That potentially causes sub-optimal system signal to noise ratio. Some pre-amps allow the user to adjust volume for each input to alleviate this minor annoyance.