Classic Audio MC Pro Phonostage Review

[JSmith]

At what gain did you test it ?
There are 2 settings: 63dB or 73dB, but your measured gain is right in the middle.

It was stated at the beginning of the review just before the dashboard;

Tested gain setting was 63.

JSmith

 

[AudioSceptic]

Have you ever considered that such thing can be actually benificial for some recordings? For example, it can create a sense of weight, bring fullness, etc. and it's a mixing engineer, who decides whether to cut or leave it

I suspect that that might be why this recording is an audiophile favourite.

 

[Dave147]

Let's swap in some LM4562s and retest! They look like NE5532s in there. Is there any difference with OP Amp rolling?

Check out his website to find out why not to bother. He explains all.

 

[Dave147]

I have the MM version and it's very good sounding. I was supplied with the measurements of my actual one. It is expensive but I don't mind paying the extra just for the quality of this phonostage. Plus it helps Michael improve his products and make new ones. It's a quality product that has a lot of attention to detail. Plus his website is definitely worth a look for an insight into why he used the components he did. And why not to change them !

 

[F1308]

We're talking audio output levels at 2V upwards as regards dacs and amps, the spectacular results with Class D amps 'helped' by less sensitive inputs needing less gain I understand. Input sensitivities of old were in the hundreds of millivolts back in the day (and Hegel and others still abide by that to a degree, hence the higher noise figures from memory due to the gain structure)

In a phono stage, we're talking a measurement average level in the groove of 5cm/s, where most 'MM' types give 3 - 5mv output and where MC types are around a tenth of that and sometimes lower, so extra noise is inevitable, especially when the inverse RIAA curve is applied, boosting lower frequencies and reducing higher ones. This is a MOVING COIL phono stage and for such a type, this one is excellent! The 'sinad' of a vinyl record (*estimated* at various frequencies) could be as high as 65 - 70dB at high frequencies with a new top quality highly profiled stylus and a spotless new record played but once and as low as 10dB or worse down at sub 50hz levels, the midrange somewhere between 20 and 40dB depending on all manner of factors from stylus to the player itself... I'm not able to give chapter and verse let alone proper technical evaluation, but do hope Mr Fidler and others with proper test gear can properly expand definitively on this.

Very interesting.
Many thanks.
But in mid 2023 those numbers are poor,
another technology already available.
Keeping my vote.

 

[Ismapics]

Hello @amirm and community

Question, does that mean that the most SINAD you can extract out of a Turntable is about 73db? Regards, iml

 

[keiron99]

Very interesting.
Many thanks.
But in mid 2023 those numbers are poor,
another technology already available.
Keeping my vote.

You seem to have taken a strong disliking to this product. Could you please explain why? What's the other technology you refer to?

 

[dsnyder0cnn]

I've been really enjoying the Parks Audio Puffin, but I've kept my eye open for an analog alternative with balanced outputs that I could have on-hand for comparisons. Objective measurements between the Puffin and this MC PRO are quite similar, so I would expect them to also sound similar.

 

[dsnyder0cnn]

You seem to have taken a strong disliking to this product. Could you please explain why? What's the other technology you refer to?

Perhaps he thinks this is a DAC or preamp instead of a phono stage?

 

[dsnyder0cnn]

the most SINAD you can extract out of a Turntable is about 73db?

Considering complete vinyl transfer function from production through playback, a SINAD of 73 dB is highly optimistic, even when everything is just right (almost never the case).

 

[restorer-john]

I just checked and my image was from the MM PRO unit. It used 5532D in the section that I captured.

The excellent high resolution shots here show you the ICs, and also he's been kind enough to mark on the PCB the type numbers on the MC Pro:

MC Pro Moving Coil Phono Stage by Michael Fidler

Low noise discrete input moving coil phonostage, with linear power supply, high RIAA accuracy, mono switch and low frequency crossfeed

michaelfidler.com

 

[JSmith]

The excellent high resolution shots

Classic Audio MC Pro Phonostage Review

You should ask yourself why so many devices send in by the manufacturer fail on Amirs work bench That doesn't mean, that some devices aren't prepared. Btw: I didn't say, every device would be prepared. But you don't know, which one. Even a failed device could have been a (poorly) prepared...

www.audiosciencereview.com

JSmith

 

[EJ3]

I wanted to see the MM version with those options.
Probably not the thread to ask about this.

I thought that this might be of interest (I think that it is well worth the time to peruse his site);
I pulled these items from the FAQ page of Michael Fidler - Classic Audio Ltd.:

Company
About
FAQ
Articles
Contact
Products
Ordering
PRO series
SPARTAN series
Testimonials
External links
Facebook page
YouTube channel
Twitter
Review index
Copyright © Classic Audio Ltd - 2023

Can I customize cartridge loading?​

Absolutely not. This rather tricky subject is soon to be covered in a series of articles on moving magnet and coil input circuitry, but it has been revealed through quite extensive research that variable loading is quite undesirable for 99% of applications. Variable loading inevitably deviates away from optimal rejection of radio frequency interference, increased insertion loss in moving coil inputs, and can increase noise and seriously distort the high frequency response of moving magnet cartridges. For the latter, my phono stages are optimized for a total input capacitance agreeable to virtually all MM cartridges on the market once tonearm and cable capacitance are taken into account.

Do you offer a PSU upgrade?​

No. This question seems to appear perennially as a result of the dubious marketing strategies of other companies, seemingly designed to wring as much cash out of buyers with little regard to evidence of benefit. Customers are happily informed that the 'standard wall-wart' supplies offered with all units are entirely optimized and there is no benefit to be obtained by using different, more expensive units. In fact, quite the opposite, as I have yet to see a transformer-based power supply that offers as low an idle power consumption and capacitive isolation from the mains as the types supplied.

Supplied PSUs are linear types as standard, and while they are contained within 'wall-wart' enclosures, giving the initial impression of low-cost design choices, they are a world apart from the cheap switching PSUs that are unfortunately so often included with modern audio equipment. Swapping them out for other types is highly discouraged as doing so can potentially overload the product's internal rails, cause the regulators to drop out, or inject excess noise. I don't believe in wasting my own, or customer's time making sub-optimal products. Customers are advised to spend their excess cash on records!

 

[restorer-john]

Classic Audio MC Pro Phonostage Review

You should ask yourself why so many devices send in by the manufacturer fail on Amirs work bench That doesn't mean, that some devices aren't prepared. Btw: I didn't say, every device would be prepared. But you don't know, which one. Even a failed device could have been a (poorly) prepared...

www.audiosciencereview.com

JSmith

This is what I am referring to. The angled shots, although higher resolution don't show all the type numbers as some are obscured.

 

[EJ3]

If the sensor resonance is 15 Hz its output needs filtering below 30Hz which is the frequency at which the headshell becomes a close approximation to stationary relative to the record.

Headshell, one of the reasons that I bought a Technics SL-M3 linear tracking (with a Titanium Nitrite tone arm) & T4P (P-Mount) turntable many years ago.
I also have a DUAL 1229 with it's stock tone arm.

 

[Mnyb]

If 30Hz is a good compromise for most cartridge and arm combinations , I'm ok with that .

I'm sure it can be both higher or lower , but rarely at the lower end ??
I'm not qualified at answering where it typically lands .

So if the typical resonances makes the playback system unreliable below 30Hz we might need that compromise even if <30Hz sound are in the pressing.
Like @Frank Dernie said it migth play these if they are on the disc but not at a correct level , possibly with higher amplitude ?

I also have qualms about modern vinyl done from digital sources do they really know what they are doing nowadays ?

I would draw the line at if the records is a digital production ill stick with a digital format .
And use vinyl for an old collection or old oddities and pressing that simply not exist in any other way , sadly i sold my vinyl collection, some disc where unobtanium ?
So if i get a vinyl player again it would be for nostalgia and just the charm of doing it

Btw what would the cutting lathe say about <30Hz would it perform well or will it also be compromised ?

 

[Mnyb]

Hello @amirm and community

Question, does that mean that the most SINAD you can extract out of a Turntable is about 73db? Regards, iml

MM or MC on MC I supose this is the physical limit , but the vinyl noise itself is also there .

For all the youngsters MC inputs are by nature noisier due to physics and you read the SINAD chart with that in mind .

I have fond memories off when swiching to MC increased the noise on your amp .

There are also the posibiluty of an input transformer ?

But it's a bit over my head , I suppose the Pickup coil itself gives a a physical noise limit as a generator of the signal and the whole system should be considered together as a unit and I don't know this topic well enough to explain more .

 

[EJ3]

I have the MM version and it's very good sounding. I was supplied with the measurements of my actual one. It is expensive but I don't mind paying the extra just for the quality of this phonostage. Plus it helps Michael improve his products and make new ones. It's a quality product that has a lot of attention to detail. Plus his website is definitely worth a look for an insight into why he used the components he did. And why not to change them !

And some interesting Do It Yourself stuff.

 

[DSJR]

Headshell, one of the reasons that I bought a Technics SL-M3 linear tracking (with a Titanium Nitrite tone arm) & T4P (P-Mount) turntable many years ago.
I also have a DUAL 1229 with it's stock tone arm.

According to tests in the 80's, the T4P mount offers a fair amount of lower midrange colouration as the joint isn't very good (as tested and it's enough to show on cartridge response traces). The trend for solid tonearms from pivot to headshell does have some advantages.

Interestingly, the Dual shell-carrier arrangement in your 1229 (and my 701/601/1214/1019/1009SK2 - Gawd I'm sad), gives these tonearms a lively structure above 1kHz, but fitting a metal mount pickup (AT20SLa back then and VM740 now, as well as a few MC's I've tried - EEK!!) seems to mute this aspect nicely...

P.S and off topic - make sure the 'rubber tubing' around the 1229's tonearm height assembly locating balls underneath is replaced as if not, the height lever will jam and the infamous 'dearing ring' on the bottom of the arm outer gimbal will fracture - it can be repaired now but it's a royal pain and needs fine engineering skills.. Forgive me if you know this already

 

[manisandher]

I have the MM version and it's very good sounding.

I've just ordered an MM Pro to use with my Decca/London Reference MI. The plan is to use it with my E1DA to digitise some of my older/more precious vinyl. Its high output level combined with its low output impedance should make it a better match for the E1DA than my current phono preamp.

Will report back once it's here and I've had a chance to try it...

Mani.