How low are we talking? What cartridge is it?
Increasing a Low output MM
Hi I have a low output MM cartridge. I am looking at a low gain phono stage; a gift.
Is there anyway to increase the output of a low output MM cartridge?
Previous posts have suggested that a SUT will not work due to impedance changes produced by the SUT.
Any other options, other a new cartridge?
Thanks
Dear @mdrone : Which phono stage do you own? , normally a MM phono stage comes with 40db gain.
Regards and enjoy the MUSIC NOT DISTORTIONS, R. | |
I’m thinking, set yourself up for future MC cartridge while you solve this problem This seems to be a versatile unit, I’m sure there are others
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mdrone I am using a Tavish Design Adagio with a Soundsmith Carmen II cartridge with an output voltage of 2.12mv , the MM ( MI ) gain is 44db . I was unsure if the gain was enough when I switched from a Grado with an output of 5mv since I am going thru a passive attenuator . If you think that 44db is not enough I believe that Manley makes a phono pre that is adjustable up to 50db . | |
@mdrone : Thank's. According the real time measurements made by J.Atkinson in theory the true gain is a little over 37db so you don't have to have a problem running your cartridge other that maybe a higher than normal noise levels but the critical issue with your unit is that its RIAA accuracy is really poor and goes against the quality levels that your cartridge can shows:
https://www.stereophile.com/content/leben-rs-30eq-phono-preamplifier-measurements
R.
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Paradox phono-30 amplification is done via a pair of LSK170 JFET to providing 30dB gain and an external plug for loading your cartridge with any value resistor.
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The problem is that the Leben has abnormally low gain. Most MM phono stages offer around 40db of gain. I have had the Leben in my system and quite frankly it is quite vague - not worth the money in my view. Even a cheapy Soundsmith phono at around $1k was significantly better. My suggestion would be to get another phono stage or if you have the Leben, sell it and use the money for another phono. | |
Did you discuss budget. This versatile ModWright tube mm/mc was listed 4 days ago, plenty of gain (read the manual for facts). note: canadian dollars https://www.canuckaudiomart.com/details/649985374-modwright-ph-90x-tube-phono-stage/images/4486346/
https://www.modwright.com/sources/ph-90-tube-phono-stage.php ..................................................... Another versatile unit
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@mdrone as you have a Soundsmith cartridge you may wish to consider a Soundsmith Phono. https://www.sound-smith.com/phono-preamps/soundsmith-mcp2-phono-preamp. I’m using an MCP2 MKII with my Zephyr MIMC on my Gyrodec w/ SME M2-9-R tonearm and I’m very happy with it. In all honesty I expected this little SS phono to have a temporary place in my rig. It’s still here after 3 years.
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Now that I look more closely at the cited phono stage -- as others are saying, this Leben RS - 30 EQ is spec’d at only 23.5dB gain, which is way too low, crazy low. I personally avoid MM stages below even 40dB. However, the picture gets much more rosy if we check out Stereophile’s actual measurements of a review unit:
37dB is serviceable. You may still desire for extra gain when using a lower output MM or high output MC (below 2.5mV), but it’s workable. The Hagerman Piccolo I previously suggested has a lowest gain setting of 12dB which would add up to 49dB -- a bit on the high side, but could be beneficial over 37dB in certain cases. Unfortunately when we read a bit deeper into the Stereophile article the picture gets a bit less rosy again:
That’s poor signal-to-noise performance for an MM stage, much less one on the left side of the MM gain bell-curve. Adding an active head-amp gain stage will just make this worse. You might just try the phono stage as-is and see if your line stage + amp gain can cover for it. Given the measured performance of this unit, I think it would perform best with very high output MM’s 4mV - 5mV+. I know the Ortofon 2M series has a very high output level; I don’t know of others as I mostly stick to MC’s. Stereophile reported high overload margins for this unit, which is good -- that means it should be able to take high output MM's, or medium output MC's plus a 10x - 20x SUT ratio, without distorting. If this phono stage had low overload margins, it would have to be considered a failed product. | |
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Dear @mdrone : Do it you a favor and don't put any $ on your phono stage is, is not woth to do it and a waste $. Instead invest in a new unit as this one, please read the overall review including the measurements ( important. ):
https://www.stereophile.com/content/ps-audio-stellar-phono-phono-preamplifier
R.
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