Matching cartridge gain with phono pre gain

I currently have a cambridge 640p ( mm-39db mc-55db ) which I have been using with a audio technica at-120e ( rated at 5.0mv). I find that I have to raise the volume only a bit more than normally on some records other than that it gives me sufficient gain. I will be upgrading cartridges and I am wondering what cartridge would give me more gain with the cambridge 640p? Would it be a cartridge that has an output more than 5.0mv?? My choices include :
Dynavector 10x5 MC ( 2.5mv), Benz Micro mc20e2 high mc (2.2mv), Audio Technica 150mlx ( 4.0mv) Ortofon 2m blue ( 5.5mv) Thanks in advance.

 

If that cartridge has a 5.0 mv output, you're pretty close to the max you're going to find, except for maybe a Rega cartridge. which are around 6 or 7 mv output.

 

I think you'll find that the Ortofon is easily the loudest in that list, it's one of the distinguishing properties of the 2M range. They typically measure a lot higher than 5.5 mV in the reviews I've seen.

I'm using a 2M Red with the azur 540P (also 39 dB gain) and it sounds very dynamic and punchy. Practically the same level as my CD player and definitely louder than my old AT430E/OCC, which is very similar to your AT120E and also rated at 5.0 mV.

 

IMO the high output MC's would not be a good idea with the Cambridge. Keep in mind that the output of the cartridge should be carefully matched to the gain that the phono preamp provides.

Of all the cartridges you listed above the AT 150 MLX should, in theory, work the best as ideally it requires 38 db of gain. This is, in fact, going to require you to crank the volume up on your integrated or preamp a bit more, not less, but the sound quality should be good and, for lack of a better term, very balanced.

Too much output from the cartridge and you can overload the phono preamp. Yes, it might sound "punchy" but if you overdo it that punchiness can easily turn into strident, aggressive sound caused by distortion. Too little output (or not enough gain at the phono stage) and dynamics really suffer and, even with the volume cranked, it will sound like you're listening to your speakers through two or three blankets.

I would not go to a higher output cartridge than the AT 120E with that phono stage (and I have that cartridge here in a secondary system). You are pretty closely matched (about 3 db in theory-I think one can function being 3 db or so too high or low but once you get beyond that it becomes sketchy) now; going with a higher output may be "louder" but the sound quality may suffer overall.

For calculating output/gain issues, the phono preamp gain computer at

www.kabusa.com

is invaluable and, in my experience, pretty much dead on.

 

First of all, you shouldn't base or even limit your choices on gain alone. Cartridges do not provide any gain, rather they create output by loading the preamplifier. The preamp has all of the gain. You should choose the cartridge by the sound they create and the system that you are fitting it into and then limit that range simply by those cartridges that are compatable with your tonearm. The final choice is usually made by brand loyalty, price, if your favorite dealer carries it, output level, color (you should be getting the idea that it's getting more esoteric now ;-), etc.

I agree with The other two fellow members who suggested the Rega and the Ortofon as far as how they relate to your highest output question. They certainly do have plenty of output but I really don't think that is solely responsible for making them sound as nice as they do. I don't agree with what the other fellow said which suggested an over-importance of selecting the cartridge based on gain (sorry Blake). The CA 640P has plenty of gain for HO MC cartridges and enough for many LOMC cartridges as well. I think we do agree though that the idea of trying to get the output level of your turntable with your CD player, etc is not the best one for sound quality. You just need to rotate that thing on your amp which is often referred to as the volume knob a bit more. If anything, that actually helps most well designed amps to sound their best. If not, the amps likely have too much gain or a poor input arrangement resulting in excessive noise.

In short, select the cartridge that sounds best to you, helps to bring the sound of your system in the direction needed, and that is suitable for your tonearm. Most cartridges these days are designed with a medium mass tonearm in mind, so the last criteria is a pretty easy one.
-Bill

 

In the October issue of hi-fi news they measured the 2M Red to have an output of 6.6mV.

It was also the winner of their group test by the way, beating out the Grado Prestige Red, Goldring 2200 and forum favorite Audio Technica AT440MLa.

 

with your phonoe pre in MC mode with 55 db of gain, those Medium to High output MC cartridges you mentioned at 2.4 and 2.2 mv, it sounds like the right amount of gain to me. A .4 mv AT33PTG or a .25 mv Denon 103 would need more db of gain than the 55 for optimal playback.

 

Yes, I'm happy with my 2M Red. It struggled with sibilance for the first month or so, but after 2 months now (and probably 100+ hours), it has smoothed out very nicely. Together with the Cambridge 540P, I would characterize the sound as "warm and powerful". Coming from a leaner sounding Audio Technica myself, I can appreciate this "musical jacuzzi".

The 440MLa with its nude micro-linear tip for under $100, as you can get it in the US, is still the bargain though, in my eyes too.

 

I agree and that is the cart I am currently using, and the price I paid. In their group test they priced the AT440MLa at 100 pounds and the 2M Red at 60 pounds. I think they may have held that 40 pound price difference against the AT440MLa, even though in the US both of these carts can be had for around $100.

 

I found an interesting link on how to find the correct gain value for any cartridge :

http://www.avguide.com/blog/taking-the-guesswork-out-phonostage-gain

He takes the example of the Graham Slee : 41.5 db and a Benz cart 2.5mV
He finds the ratio between output voltage (1V) and the cartridge (2.5mV). In this case, the ratio is 400 (1 divided by 0.0025). Using a calculator with a “log” button, the logarithm of 400 is 2.602. He multiples 2.602 by 20 to get the number 52, which is the gain in dB required of the phonostage to amplify a cartridge with 2.5mV output to 1V.

I tried it with a 5 mV cartridge and the result is 46 dB of gain needed, seems a little high to me , what do you guys think?

 

Don’t give a damn about those figures

If I calculated right, it says I need 50,45 dB of gain to drive my Shure V15VxMR. CA 640P has 39 dB.

Man, this value is huge! I’ll never buy so powerful phono stage to my cart!
Okej, I have rotate to the volume knob a bit more, as Bill says.
So what? It’s the sound that matters. Not gain. Having heard this basicly from all experts.

 

interesting. a few people (on this forum) have advised against using the MC setting of the 640p with the Dyna 10X5 cart (2.5mV). it's never sounded like too much gain to my ears, but I don't know the technical in's and out's.

 

As a former owner of a 2M Blue, I really preferred the Dynavector 10X5 over it. My Threshold phono preamp has plenty of different loading settings but the (2.8mv) 10X5 worked just fine with the MM 40dB setting and 47K loading. And for my favorite listening level I only have to turn up the volume by just a click more than with the old (5.5mV) 2M Blue.

YMMV of course.

 

That’s very interesting. It’s a lot cheaper too.
Something to think about for all of us, if we ever get a new cart.

 

just to clarify my lousy writing, I preferred the Dynavector ($395) over the 2M Blue ($199).

 

The effect of capacitance on an MM cartridge's frequency response is another aspect to consider. I have an AT150MLX and a Cambridge Audio 640P. In the 640P manual, it lists the MM capacitance at 220pF, which is already higher than the AT150MLX's recommended 100-200pF. Once you add the capacitance of the cable between the tt and phono stage, plus the capacitance of the internal wiring and connectors, the total is approaching 300pF. If you check the Hagerman loading site, for my case, the AT150MLX's inductance of 450mH, plus 300pF of capacitance results in a resonant frequency peak at about 13700Hz, which accounts for the cartridge's brightness in this setup.

Of course this is just an example, but it bears keeping in mind when choosing a cartridge to match with the 640P. I used some parallel resistors for awhile to tame the treble on my At150MLX, but I mostly use it for needledrops and I prefer to handle the smoothing with EQ.

I notice that the other MM you're considering, the Ortofon 2M, has an internal inductance of 700mH. According to the Hagerman site, with a 640P plus cabling, etc., giving a total capacitance of 300pF, the resonant frequency peak would be around 11k, which would be even more noticeable.

 

My fault, sorry!

There’s nothing wrong with your writing. I read 2M Black! (That’s me!)
Now it’s perfectly clear to me that Dynavector sounds better.

 

FWIW, I use a Benz-Micro M2 with a rated output of 0.8 mV and a c-j P15 phono preamp with a gain of 53 dB. I get plenty of volume when I play records in my system. With your phono preamp having 55 dB gain for its MC stage you could use MC cartridges with mid output (around 0.8 mV) in your system. IMHO, this would make a noticeable improvement in the sonic presentation of your records.

 

It does matter and is a well known consideration with MC carts, not so apparent with MM - as they don't represent such a wide range as MC - but still there. The cart and phono stage form an integral electrical system and any mV specification you see from the manufacturer is valid for a typical setup, not an absolute value. The real output of a cartridge is dependent on the characteristics of the phono stage you connect it to. In general, low gain will make the sound dull and lifeless, too much gain and it will start to sound pushy and congested. In the same vein the referenced calculation is a guesstimate at best.

Now the fact that many users prefer to run their HO MC cart into the MC input of the CA 640P is in my opinion attributable to the better gain match in this case (and not so much the different resistive/capacitive loading as many suspect). A 2.5 mV (at 47 kOhms) Dyna 10X5 will drop its output dramatically into a 100 Ohm load as given by the MC input of the 640P. Therefor you're not getting the full 55dB gain on 2.5 mV, but maybe on 1.3 mV only. This probably still improves on the normal 39 dB gain of the MM input, making for a more full bodied and pleasing sound. It's more a lucky coincidence than by design, I gather.

 

I think that you are over-analizing it. If you plan on using a cartridge with 5mv output, then any MM stage will be adequate. Buy the phono stage based upon its sound, not its gain. Gain means very little when you consider all of the other ways for a preamp to screw-up the sound. Just buy a phono stage already... geesh .
-Bill

 

+1 2M Red is the hottest MM I've had the pleasure of, produces pretty bang on compatible levels used with the 540p. Almost forgot I had a volume control

 

I'll have to take the opposite side in this contest. I had a Dyna 10x5 on my Sony PS-X75, loved it. My next cart was a 2M Blue on a Sony PS-X5. I use the phono stage on my Marantz 2235b, which sounds quite excellent, very spacious and warm.

To my surprise, the 2M Blue sounds better on my system than the 10x5. Perhaps it's just closer to my own ideal sound: strong and deep bass, clear and sharp detail, sweet and smooth, yet neutral and honest.

I've noticed that I felt the same way towards the AT 440mla over the Denon DL-160. In both instances, the MM cart sounded sharper, more detailed, more clear, more widely defined. And the MC carts were both high-output. I realized that cartridge loading was the key, and this is where HOMC carts fall in between the cracks.

I'm sure I still haven't heard the Denon or Dynavector at their full strength. But I know from my own experience that the "standard" MM and MC settings are not ideal, while a strong MM like 2M Blue will perform its best.

These are all excellent carts, of course. In the end, I think much comes down to personal taste.

 

Up for more people with experience using a CA 640p (or 651p) with a dynavector cart. I'm curious to try the 20x2H in the MC inputs as well.