MM Phono input vs. MC Phono input

[MarSanZ]

I just purchased a Sumiko Blue Point Special Evo III cartride with a 2.5mV output. Some consider this high enough to run through a MM phono stage. I am using a Mcintosh C2300 preamp, since the cartridge is Moving Coil it makes sense to use the MC phono input. Are there any advantages over using the MC phono input over the MM phono input? Does it matter?

Thanks.

MarSanz

 

[ETI_5000]

2.5mV is easily high enough to use into a normal MM phono input. The MC input is only for low output MC cartridges, which typically put out only one tenth the voltage your Blue Point does. Using the MC input will most probably overload it, and cause distortion, as it's designed to amplify about 10 times more than the MM input, which your cartridge doesn't need. In fact, the instructions for the Blue Point will most likely tell you to use it into the normal phono input. Don't think of them as MM and MC inputs, even if that's what the labels say. Think of them as low input and high input phono stages, and your cartridge is a high output cartridge, so should be plugged intio the high input phono stage.

-Don

 

[iLUVanalog]

2.5mV is easily high enough to use into a normal MM phono input. The MC input is only for low output MC cartridges, which typically put out only one tenth the voltage your Blue Point does. Using the MC input will most probably overload it, and cause distortion, as it's designed to amplify about 10 times more than the MM input, which your cartridge doesn't need. In fact, the instructions for the Blue Point will most likely tell you to use it into the normal phono input. Don't think of them as MM and MC inputs, even if that's what the labels say. Think of them as low input and high input phono stages, and your cartridge is a high output cartridge, so should be plugged intio the high input phono stage.

-Don

correct....definitely use the moving magnet phono stage for the high-output MC.

 

[Mr. Lin]

I'll echo this one more time, you definitely want to use the MM setting, MC would be too much.

 

[MarSanZ]

2.5mV is easily high enough to use into a normal MM phono input. The MC input is only for low output MC cartridges, which typically put out only one tenth the voltage your Blue Point does. Using the MC input will most probably overload it, and cause distortion, as it's designed to amplify about 10 times more than the MM input, which your cartridge doesn't need. In fact, the instructions for the Blue Point will most likely tell you to use it into the normal phono input. Don't think of them as MM and MC inputs, even if that's what the labels say. Think of them as low input and high input phono stages, and your cartridge is a high output cartridge, so should be plugged intio the high input phono stage.

-Don

Okay, I tried both the MM and the MC phono stages. I didn't realize the distortion I was getting until I tried the MM phono stage, scary CLEAN and quiet now, wow! Thank you Don. PS - I was getting use to the warmth of the distortion however.

One thing I would like to get clarification on is this; the C2300 enables you to change the MM phono stage's PF (capacitance) between 150-750, the MC phono stage allows you to change the Ohms from 25-1000. My cartridge specs states the load impedance is 47 Ohms, which from my limited understanding is the RIAA standard for a MM phono stage, the spec sheet doesn't mention anything about the PF (capacitance) load for my cartridge.

Since I am using the MM phono stage with a high output MC cartridge, what do you recommend for the capacitance load; 150, 200, 250, 300? And does it matter? If so, how? I am assuming it does because you can change it. What would the changes be in terms of sound as well? I am using a capacitance load of 250 at the moment.

Sorry about being super descriptive and asking so many questions. I am trying to learn as much as possible from the experts. Getting into vinyl has so many unknown layers that I didn't plan for, but the rewards are WELL worth it. Any information would be GREATLY APPRECIATED!

Thanks.

MarSanZ

 

[Mr. Lin]

I think you mean 47kohms. Yes, that's the standard for MM cartridges. Does the BPS give an impedance range or simply say 47kohms? In either case, I would definitely urge you to try different settings (with capacitance too) and see what sounds best to you.

 

[lini]

MSZ: You can try different load capacity settings, but it shouldn't make a difference. Reason is that foremost MCs and MCHOs have a much lower inductance compared to MMs, so that the electrical resonance frequency will be far above the audible band anyway. Pretty much the same, albeit to a lesser degree, goes for quite a few MIs.

Whereas for a typical MM with around 500 mH the different capacity settings on your Mac will have quite an impact: Assuming 150 pf for the cabling, which adds up to the load setting of the amp, you'd have the resonance at ca. 13 kHz in the 150 pF setting or at ca. 7.5 kHz in the 750 pF setting. If you do the same calculations for a typical Grado MI with ca. 50 mH, you'll get ca. 41.1 kHz and 23.7 kHz respectively. And for a Goldring Eroica H (an MCHO with 0.2 mH): ca. 649.7 kHz and 375.1 kHz. I guess that should answer the question...

Greetings from Munich!

Manfred / lini

 

[MarSanZ]

I think you mean 47kohms. Yes, that's the standard for MM cartridges. Does the BPS give an impedance range or simply say 47kohms? In either case, I would definitely urge you to try different settings (with capacitance too) and see what sounds best to you.

A few updates, I changed the PF load to 300 and the sound became much more detailed and richer and less grainy, I like it. You can do so much with the C2300. Two things that blew me away though, I was using a Cloud 11 iso-platform and had to send it back because it was cracked. Talk about disappointed, not because I had to send it back and wait for a new one, but because of how great it made my TT sound! I highly recommend it for the Scountmaster, it definitely works.

Secondly, I tried a pair of AQ Diamondback interconnects with the TT, I don't want to hijack the thread and start a interconnect debate, but they get two thumbs up from me:thmbsp::thmbsp:. Excellent presentation, opened up the soundstage and smoothed out the delivery of the music...BRILLIANT!

I am quite the happy campers these days...thanks everyone for your input.

MarSanZ

 

[Mr. Lin]

A few updates, I changed the PF load to 300 and the sound became much more detailed and richer and less grainy, I like it. You can do so much with the C2300. Two things that blew me away though, I was using a Cloud 11 iso-platform and had to send it back because it was cracked. Talk about disappointed, not because I had to send it back and wait for a new one, but because of how great it made my TT sound! I highly recommend it for the Scountmaster, it definitely works.

Secondly, I tried a pair of AQ Diamondback interconnects with the TT, I don't want to hijack the thread and start a interconnect debate, but they get two thumbs up from me:thmbsp::thmbsp:. Excellent presentation, opened up the soundstage and smoothed out the delivery of the music...BRILLIANT!

I am quite the happy campers these days...thanks everyone for your input.

MarSanZ

Glad to hear it. Audioquest makes nice cables, particularly the river series, which most of us (myself included) have to buy used do to the price.

 

[MarSanZ]

I have a follow up question regarding this post. I noticed that when I changed from a MM, 5.5mV to a MC, 2.5mV, I know have to turn my volume up further to get the same loudness. Is this normal? Is this why some use a step up transformer?

Thanks.

M.

 

[Mr. Lin]

I have a follow up question regarding this post. I noticed that when I changed from a MM, 5.5mV to a MC, 2.5mV, I know have to turn my volume up further to get the same loudness. Is this normal? Is this why some use a step up transformer?

Thanks.

M.

Yes, that's normal, and no, you absolutely do not need a step up transformer, those are for very low output MC cartridges. The cartridge has lower output, so you make up for that by increasing the volume a little.

 

[ETI_5000]

I have a follow up question regarding this post. I noticed that when I changed from a MM, 5.5mV to a MC, 2.5mV, I know have to turn my volume up further to get the same loudness. Is this normal? Is this why some use a step up transformer?

Thanks.

M.

Yes.

No.

It's normal that you have to turn up the volume more if you're only putting out just less than half the voltage - what else did you expect? Step up transformers are used to step up the voltage of low output MC cartridges, which might put out 1/10th of the voltage your high output MC cartridge puts out. That is, they may only put out around 0.2 to 0.4mV, so a step up (like my Denon AU-320) will raise the voltage by roughly 10 times to about the same as your cartridge. You don't need to use them on your high output cartridge - just turn up the volume slightly - it's designed to go into the same input as a MM cartridge, and using a step up on your cartridge will increase the voltage to overload (distortion) levels, particularly on loud signals, so don't do it. Just put some music on, and forget that anyone told you it was a MC cartridge.:thmbsp:

-Don

 

[quicksand]

Dusting this one off...

So I have a MC (low input) preamp on the way and only have MM cartridges on hand. The MC Phono module is rated for 1.2mV and less.

The output of the MM cartridge I would be using with it is rated at 6.8 - 7.2mV.

Question being - would I experience distortion at any volume level or could I use the MC/ MM combo safely without overloading it?

The pre is only for low input - doesn't have high input option.

 

[arcorob]

Just to clarify

DONT use HOMC or MM's with MC settings.

Part of what the MC stage does is step up the signal...from 10x t0 15x (some 20x

So a LOMC running at .3mv gets boosted to about 3 to 4.5mv - MM range.

SO you take a HOMC running already at 2.5mv...and what do you get ...? DANGER WILL ROBINSON...25 to 32mv !

Now running that HOMC on the MM side, at 2.5mv its going to be a bit low compared with a CD, line level but that's OK !!

Quicksand...DONT use the MM on the MC stage. Period. Just do the math above..also...you can see what your MM carts are rated at...they will ALL be above 1.2mv so that should tell you...INCOMPATIBLE

Hope this helps

 

[quicksand]

Understood - or so I think.

It is all about gain and capacitance (not sure how much I understand capacitance loading though)

Guess what I was asking is at low volumes would the combo be usable - for what you are saying it isn't safe at any level.

Then I ask what harm could come of it - or is it purely sound quality related?

Guess I wont be trying this one at home...

Thanks!

 

[Bob_in_OKC]

Dusting this one off...

So I have a MC (low input) preamp on the way and only have MM cartridges on hand. The MC Phono module is rated for 1.2mV and less.

The output of the MM cartridge I would be using with it is rated at 6.8 - 7.2mV.

Question being - would I experience distortion at any volume level or could I use the MC/ MM combo safely without overloading it?

The pre is only for low input - doesn't have high input option.

Sounds like you're using a Rega cartridge? What's this preamp you have on the way?

 

[4-2-7]

DONT use HOMC or MM's with MC settings.

Part of what the MC stage does is step up the signal...from 10x t0 15x (some 20x

So a LOMC running at .3mv gets boosted to about 3 to 4.5mv - MM range.

SO you take a HOMC running already at 2.5mv...and what do you get ...? DANGER WILL ROBINSON...25 to 32mv !

Now running that HOMC on the MM side, at 2.5mv its going to be a bit low compared with a CD, line level but that's OK !!

Quicksand...DONT use the MM on the MC stage. Period. Just do the math above..also...you can see what your MM carts are rated at...they will ALL be above 1.2mv so that should tell you...INCOMPATIBLE

Hope this helps

ha ha ha I use a HOMC on the MC stage and it sounds better than the MM side

 

[Bob_in_OKC]

I've heard of people thinking a HOMC sounds better on the MC input than on the MM input. If they give the MM side an extended careful listen they ordinarily realize it is better after all.

 

[4-2-7]

I've heard of people thinking a HOMC sounds better on the MC input than on the MM input. If they give the MM side an extended careful listen they ordinarily realize it is better after all.

I did, I ran my Blackbird a week on my MM. Then said what the hell might as well try the MC side and it was awesome. I am also and am sure it's wrong too,I have another setup like this. Blackbird to SOTA Head Amp then into the MM phono of the preamp. I have the amp at 100 ohms and at high gain, this has totally opened the depth and soundstage.

 

[Tedrick]

Understood - or so I think.

It is all about gain and capacitance (not sure how much I understand capacitance loading though)

Guess what I was asking is at low volumes would the combo be usable - for what you are saying it isn't safe at any level.

Then I ask what harm could come of it - or is it purely sound quality related?

Guess I wont be trying this one at home...

Thanks!

It's all about gain and resistive loading. Capacitive loading applies only to MM cartridges, and very few phono stages have adjustable capacitive loading.

The volume you'll be listening at makes no difference in this discussion.

While sound quality is an issue, overload is the elephant in the room. Using a MM or HOMC cartridge into a LOMC phono stage could overload circuits in the phono stage. The result will be distortion that could damage something down the line.