MC Cartridge Gain... Higher or Lower?

I can't find a whole lot on the subject, and what I do find is a bit conflicting.

Currently I have a 0.3mv output cartridge. According to the KAB calculator, proper gain should be 61dB. My upper options with the Lehmann Black Cube SE II are 56dB and 66dB. Is there a good reason to go or not to go with one over the other? I don't really want to invest in another phono stage. Or do I need to?

 

A lot depends on other factors, such as, the amount of gain from your linestage/amplifier, the sensitivity of those components (how much voltage is required for full output). Generally speaking, with that cartridge output you should be able to work with either phonostages. I would prefer the 66db output phonostage with.3mv myself, because that would provide a better margin in case the linestage or amp doesn't have much low level gain itself (that output will not be enough to overload any linestage/amp using that cartridge). In my own system, I have a headphone amp that is very low in sensitivity and so it has to be operated close to wide open when I play records with my current cartridge which as an output close to .3mv feeding into a phonostage with 60 db of gain.

 

You're fine. Try them both and use which one you like more. The only possible issue is if the higher gain causes breakup or distortion because it's overloading the preamp as Larry mentioned, but I doubt that will happen with just that little bit extra gain. I'm using a Jolida JD9 with ~70db of gain with my .3mv cartridge and it sounds excellent.

 

Yep, I'd say try both (start with preamp volume low 'just in case' and raise to normal listening level). The higher gain should result in a lower setting of the volume control, it may be 'dramatic' or not so much ... try turning up the volume control higher than normal setting, without a record playing, and listen for hiss, hum, or whatever. If that noise (if any) starts up at a much higher volume control setting than you would ever use, that's a good thing! See what the volume control setting is compared to when you use other sources. If the preamp has a 'trim conrol' for each input that's a good thing too, can match levels between inputs so you don't get blasted when switching to CD or whatever. Otherwise just note the position or setting and set accordingly.

IIUC, actually 6dB of difference should be about twice/half as loud ... or is that 10dB? I know in power, 3dB is 2x, but we're not talking about power. I'd say either setting should work just fine, as others pointed out, maybe the higher gain could 'overload' the preamp input but that's probably not going to be the case. The higher gain setting may be a little noisier but again if you don't hear anything bad at normal volume control settings or even much higher than normal then I'd say all is well and try both ... and also some preamps are quieter or sound better with a particular volume setting, so there may be an advantage there for one gain over the other.

happy listening!

 

Neither are ideal. I have found that with most systems you want to be within 3 dB, preferably 2 dB relative to the KAB calculator. 5-6 dB out and things start to get dicey.

That being said, try both as others have suggested. My gut feeling is the the low setting will be the worst compromise: more noise, very compromised dynamics and kind of a listening through a wet blanket sound. On the other hand, the higher setting may be a bit aggressive, with a "hardening up" of the sound.

The one thing that might work in the favour of the lower setting is if your cartridge actually has a slightly higher output than rated. I have a couple of Denon 103R's here that come with an individual spec sheet and both output about .30 mV vs. the typical .25 mV spec'd by Denon.

 

I hear the within 2 rule as well. I can get all around the ideal number for mine and end up with 58.4 db gain. I can do 59.4 and 60, but I go with the slightly lower value because I get less grain at those high-energy moments. I hate to say it because I'll get flamed, but you can get those inline attenuators and bring it right down to 60 db. If you end up feeling that it sounds better at that level or detect issues with the high or low gain settings, you might then consider a different phono preamp.

 

What cartridge are you using? Just curious.

Some numbers: the KAB calculator recommends 56dB for a 0.5mV (1kHz @ 5cm/s) cartridge. The difference between 0.3 and 0.5 mv is 4.44dB. It also recommends 66dB for a 0.16 mv cartridge. The difference between 0.3 and 0.17 is 5.46dB. So it looks like the better choice is 56. But, like others suggested, try both and see.

 

I'm using an Ortofon Cadenza Bronze with a Lehmann Black Cube on a VPI Scout 2.

I've tried both ways. At 66dB, I barely need to move the pot to get it at a nice level, 10 o'clock maybe. At 56dB, 1 o'clock gets about the same amount of loudness.

It sounds more lively at 66dB but I think it's perhaps a placebo since its louder. I know when I record with it at 66dB sine 45rpm singles will be too loud for my Duet since I can't turn anything down and I get clipping. Most LP's seem to peak right around -2dB.

 

Thanks. Isn't the Cadenza Bronze 0.4 mV?

 

Yep. He should use the 56db setting. Lower almost always sounds better anyway, unless you ever get to the point where you are using a lot of linestage gain. He should be near unity gain on his linestage with the 56db setting, which is optimal.
-Bill

 

Bill,
Do you think you could elaborate a bit more on some of this? I recently was and am still deciding on which settings to use as well. I went from a Dynavector 10x5 to a kiseki blue ns - so from 2.5mV to .44mV . I have a rogue audio triton which was on the lowest gain setting - but had to turn the volume way up with the new cartridge so i then bumped the gain up a notch. Which leads to my point/question - is it better to have the gain set lower and turn your amp up higher or move the gain higher and keep your amp lower? and why ?
I have a Rogue cronus magnum and know that you sell Rogue so that is also why I am directing this at you
thanks

 

Gain matching, in my experience, is a big deal. Too much can be seductive for a hot minute, but like KT88 said, just a little less than optimum works so nice.

 

.1 mV doesn't sound like a lot but it is. So the cartridge is .4mV.

No question the 56 dB setting is what you want which, coincidentally, puts you within 2 on the KAB calculator as well. It should sound significantly better, and more natural than the 66 dB setting, which would probably sound a bit edgy and aggressive by comparison.

1 o'clock on the volume is a reasonable spot to be as well. If you were at 4 or 5 o'clock and running out of gas that's an indication that you need more gain.

 

I would set it at 55db and 300 ohms. Because it'll sound better that way.
-Bill

 

you know its interesting that you suggest that. the shop where i get everything recommended i leave it at 47k. in reading i saw that 10x the internal is where it should usually be so 400. so i tried it at 1000 and then at 300. each step lower seemed to take away the cartridges space and flattened out the soundstage. i ended up moving back to 47k. is that unusual?
ps - im not trying to threadsteal i can make a separate post - but i thought maybe my question of gain in general might be helpful or at least bring out more information.

 

Well, gain is different from loading but they both effect the sound of a cartridge, obviously. I prefer to use as little gain as I can to achieve the needed results, which usually results in lower noise and a less strident or grainy sound. I also tend to load down a cartridge as much as I can within its range to get it to produce deeper bass and effect a softer top end. You can of course go too far with that and it is system dependent. So if the cartridge already has a soft top end, then going a touch higher in loading can open it up. In your case, you may have some warmer sounding speakers and the amp is certainly a touch soft at the highest frequencies, so I can see having too much of a good thing in that case. If you find that it sounds more natural by only loading it at 47k, then that's what you should do as no harm can come from it. There is typically not much difference in 1k and 3k settings for instance and when you go all the way to 47k, it can be just a slight bit more extended on top by comparison. Loading down a cartridge with 100 ohms and below though and things change much more dramatically.
-Bill

 

Well it seems that I'm an absolute idiot! I could have sworn I read it was 0.3mv, but there it is right in the specs, it's 0.4.

So thanks to everyone for getting me the correct info!

Now about this 300 ohm loading... ? I think I only have a few options on the Black Cube, 47k, 1k, and 100R. I was told to use 100R. 47k is only if I have it in MM mode, and I'm not sure what 1k is, or what it does with the 100R also active.

 

LOMC Ortofons like to be loaded down so just set it to 100 Ohms and forget it. Only if you had options below that would I start to experiment.

Bill (KT88) was responding to a different poster with a different cartridge when he recommended 300 Ohms.

 

Ortofon recommends 50-200 ohms ... 100 ohms

 

Exactly, the 300 ohm recommendation was for a different cartridge. The Ortofon Bronze will like to see the 100R setting.
-Bill