Acoustic Sounds

MoFi Electronics

MasterPhono

MoFi MasterPhono
By: Michael Fremer

August 17th, 2023

MoFi Electronics' MasterPhono™ Combines Versatility And High Sonic Performance

transimpedance and voltage gain inputs, remote controllability and much more

Put yourself in the shoes of an audio designer like industry veteran Peter Madnick. You are tasked with creating a phono preamplifier at a given price point. In the case of the MoFi MasterPhono phono preamplifer, around $6000. That puts it not at the “luxury” level, but well above “entry level.”

 Absent price constraints a designer can offer high sonic performance and a generous feature menu, but as the price drops, the higher becomes the tension between features and performance.

Madnick set high design bars for both features and performance and then got down to figuring out how to offer both for $6K For instance, the best way to minimize noise and increase S/N ratios would be to locate the power supply outboard in its own chassis, but a second chassis and an umbilical would add to the final price and perhaps limit other features.

 His “workaround” puts two boxes within a single framed structure sufficiently separated from one another and ground-isolated. The power supply and microprocessor control business are upfront, adjacent to the front panel’s buttons and knobs, while the low voltage signal processing circuitry is in the rear, just behind the panel mounted RCA and XLR inputs and outputs. The most sensitive circuitry containing discrete JFET amplification and passive RIAA are separately housed within a temperature sensitive, shielded copper enclosure.

Copper tube conduits, one on each side of the interior frame adjacent to attractive outer wooden side panels (available in both walnut and black finishes) and one in the center, move shielded D.C. back to the main board on one side and on the other A.C. from the rear panel IEC jack to the upfront power supply. The middle tube routes remote control function ribbon cables.

 Feature Packed Functionality 

You have a choice of three chassis mounted rear panel inputs: a transimpedance MC input for which you can choose either single ended RCA or balanced XLR input (but simultaneously not both), plus a single ended RCA and balanced voltage gain based MM/MC input that’s front panel switchable. In other words, you can simultaneously use both voltage gain inputs and switch between them on the front panel.

Each input “remembers” its settings, including (if applicable) gain, loading, mono/stereo and subsonic filter. A front panel mounted rotary switch sets 40, 50,60 and 70dB gain (nominal, depending upon whether you are using the unit single ended or balanced). A second rotary knob selects loading of 15 0hms, 30, 50, 75, 100, 500,1K Ohms, 10K Ohms, and 47K Ohms + 150pF. There’s also an “options” position that selects the rear-mounted RCA jacks where you can insert your resistive choice loading plugs. This is far more convenient than having to open things up to install resistors into board mounted sockets. Subsonic filter and mono buttons sit between the input and loading knobs. The only missing option is capacitive loading for the MM setting, which is pre-set to a very reasonable 150pF.

Directly above the input knob and adjacent to a pair of large VU type meters is a multi-function “meter” button. A brief press toggles on and off the meter backlight. Simultaneously pressing and turning the input knob adjusts LED and meter backlight brightness.

 Pressing and holding the button puts the meters into “mode 1”. Playing the first track on the Analogue Productions Ultimate Analogue Test LP you use the gain knob to adjust the meters to 0dB. Pressing the “meter” button again puts the meters into “mode 2”, which sums the outputs and puts the channels out of phase with one another. If the meters show zero output, your channels are electrically balanced. If there is output you’d adjust azimuth to produce a total “null” between the channels and zero output.

While that produces perfect electrical channel balance it does not guarantee maximum separation as anyone who’s used an oscilloscope to set azimuth can attest. Often one can achieve better L-R, R-L separation numbers with the balance off by .5dB or so. Nonetheless, this is a convenient, easy to use feature that will give users a reasonable approximation of ideal azimuth setting, and sometimes perfect electrical balance does produce maximum separation.

If all that functionality wasn’t enough, there’s also a nicely milled aluminum remote control from which you can select input, gain, loading, subsonic filter, mono, mute and even extinguish the front panel LEDs.

Mofi MasterPhono

 Set Up and Use

Set up was straightforward so no need to go through the obvious, though I did run it both balanced and single-ended “out”. When you first turn on the MasterPhono the front panel runs through the full LED set and lands on whichever input you last used. If you’ve used the transimpedance input all the LEDs surrounding the loading knob are extinguished. The instructions mistakenly say both resistive loading and gain LEDs are extinguished in this mode but not so. The gain LED setting remains lit, and you can adjust. That will be fixed in subsequent manual printings. It’s a minor point, but I wish both front and rear panel illustrations were presented in the manual (only the rear is) and both were more clearly drawn than the current manual’s rear panel illustration.

MoFi MasterPhono

 Sound

If you are interested in a phono preamp that imparts to what it’s fed noticeable warmth or enriched textures and detail robbing sweetness, the MasterPhono is not for you. Let’s start there. It strives for timbral neutrality and mostly achieves it, meaning it delivers a cartridge’s essential character—if I had to ascribe a tonal character, I’d say the MasterPhono is ever so slightly on the warm side of neutral. I was able to use it with more than a few cartridges, a few that are under review now, among them the $3995 Analog Relax EX 300 (.5mV output 15 ohm internal impedance) and the $2995 Miyajima Labs Carbon (.23mV output, 16 ohm internal impedance). I also ran the Lyra Atlas Lambda SL, Audio-Technica AT MC2022 and Ortofon Diamond.

The EX300 and Carbon, both wood bodied cartridges, are more similar in personality than they are different, though they do not sound identical. The MasterPhono in either voltage or current mode allowed their well-balanced but “woody” qualities to express themselves, though 15 and 16 ohm internal impedance pushed the limits of effective current mode operation and through the voltage gain input both sounded somewhat fuller, richer and I suspect more like what the designers were trying to achieve.

The ability to easily switch between current and voltage modes is not unique to the MasterPhono but it’s a useful feature offered by only a few phono preamps I know of, especially at or near this price point. When I used the current mode input with the Lyra Atlas Lambda SL with its 1.52 ohm internal impedance and .25mV output, I got to hear the “maxxed out” MasterPhono. I doubt many buyers of the $6000 MasterPhono will use it with a $12,995 cartridge (or a $300,000 OMA K3 turntable, though mine is a far less costly, though equally good sounding prototype) but it was interesting to hear the combo!

I spent a few hours the other day comparing four pressings of Van Morrison’s 1970 release His Band And The Street Choir: an original radio station service white label promo (an RL Sterling Sound mastering), a standard original green label RL pressing, the Tom Biery produced Warner Brothers reissue cut in 2008 by Kevin Gray at AcousTech mastering located at RTI’s pressing plant and finally the brand new Rhino High Fidelity issue cut by Gray at Cohearent Audio. I took notes, with all observations based on the Lyra Atlas Lambda SL into the current mode.

This is an exceptionally fine Elliot Scheiner recording produced at the late Phil Ramone’s A&R Studios that’s only sounded better and better as my system has improved over the past 50 plus years with more and more previously hidden detail exposed and a greater ability to hear into the expertly crafted mix—like the subtle use of variable reverb applied to “I’ll Be Your Lover, Too” and the dramatic acoustic guitar punctuation, the dynamics of which now produce a major “jump” factor but years ago were just “there”.

Right from the opening bars of “Domino”, which begins with a cleanly rendered guitar line and an in the room wood block, you know you are in for a great sonic ride. This is as natural a sounding studio recording and three-dimensional mix as that era produced. The MasterPhono delivered all the mix’s subtle layers and did an especially good job on the high frequency percussive transients. The cymbals on “Call Me Up in Dreamland” particularly impressed with just the right combination of sparkle and transient precision. The backup singers were all easily heard as individuals and not as a mass of voices.

The acoustic guitar on “Crazy Face” is placed well back in the mix but should be easily followed throughout. The MasterPhono managed it well. When Van’s horn enters shrieking on “Crazy Face” it should be well forward of the guitar and the fluttery modulation fast and well-focused but not at all edgy. Percussive acoustic guitar accents should cut through as musical punctuation marks and a tremeloed organ floating behind should percolate in its own juices. The MasterPhono presented all this harmonically fleshed out and spatially well-organized. A hallmark of a great phono preamp (or of any piece of audio electronics) is the ability to see deeply into a great mix and effortlessly sort out the parts without disturbing the cohesion with spotlighting. The MasterPhono did that with ease on this all versions of this album, though the new Gray mastering easily came out on top.

On the doo-wop/New Orleans-ish “Give Me A Kiss” there’s a Fats Domino-like piano part sitting in the background on the left channel that can easily get lost or lose note definition. The MasterPhono did a really good job there too. On “I’ve Been Working” you can almost hear someone pick up a tambourine and then start hitting it. On all of these pressings the exceptionally cleanly recorded tambourine zills were effectively engraved into the grooves but especially on the original and the new Rhino edition. The moderately priced MasterPhono delivered them with impressive transient precision—neither too sharp nor to soft and finely sized well back on the soundstage.

 When I was finished, I played selections from the four pressings on the CH Precision P10 also here for review. It costs $77,000. I would have written the same listening notes—which is not to suggest the two phono preamps sounded alike. Trust me they did not but both reliably expressed the relative pressing differences—though one with alarming precision painted on a black velvet backdrop.

Without switching back to the P10 I was perfectly content listening to this record, among many others of course, through the MasterPhono, feeling I was getting the full picture. When Peter Madnick was here delivering and installing it, we did a few back and forth comparisons and while he kept his opinions close to the vest he clearly heard the differences between $77K and $6K but we both were impressed and satisfied by the MasterPhono’s quiet backgrounds, nimble well extended bass performance, upper frequency transient precision, three-dimensional soundstaging, satisfying dynamics and overall timbral neutrality. Producing at this price point a high level of detail resolution and subtle textural authority while avoiding even a hint or glare or grain is difficult to accomplish. The MasterPhono does it. It's an exceptional value considering its features and performance.

After a few months of back and forth listening to both the current and voltage inputs it’s easy to conclude that if the MasterPhono can satisfy on a massive system into which it’s been, you could say, unfairly placed, in the real world context into which it will most likely find a home, it’s likely to please most listeners other than perhaps tube aficionados. While the MasterPhono’s overall timbral balance is on the slightly warm but very pleasing side, it doesn’t have the sonic glow those folks crave. Fair enough. But for everyone else the combination of an unusually full feature set and an impressive level of transparency and sophisticated imaging and staging combined with timbral generosity and transient delicacy should satisfy most listeners.  

 The MasterPhono and the Shure V15VxMR Caper

Shure V15VxMRWell into the review, a mini-controversy erupted over the “Original Source” reissue of Emil Gilels’ Brahms Piano Concertos with Eugen Jochum conducting the Berlin Philharmonic (DGG 4864502) a double LP set that the EBS team inscribed fully into the grooves—no compression no limiting, and no bass attenuation to be sure every turntable could handle it. Reviewer Michael Johnson’s Umami Red had trouble tracking parts of it. I played it through the Lyra Atlas Lambda SL on the SAT CF1-12 arm and sent a file to Michael who heard the same issues (they were more problematic for him than for me, (but then he plays in a symphony orchestra) so we decided to give it the Shure V15VxMR ‘trackability test’.

I installed the V15 on the Schröder/OMA “girder arm”, set the tracking force to 1 gram (1.5 actually, the brush lowers it .5g) and played and recorded the most difficult to track parts of side 3, which is cut almost to the label. The Shure did as advertised and tracked it best.

It was also an opportunity to audition the MasterPhono’s MM input and the results demonstrated both what MM advocates about their favorite—of course outstanding tracking, observational flat frequency response (not measured) and a full, rich “meaty” sound that lost MC sparkle and flash but gained undeniable weight and richness.

You’ll be able to hear the V15 and MasterPhono on a Gilels excerpt embedded in Johnson’s review (Not yet, because it was copyright restricted and we are trying to resolve it with DGG). The piano sound has impressive weight and body yet the transients are not softened. The combo paints a pleasing picture that even committed MC advocates will appreciate.  

On the His Band and The Streetchoir Van’s vocals and those of the background singers had convincing and honest textures, free of glare. On “Virgo Clowns” there’s a bass clarinet on the right channel and a mandolin on the left. I’m very familiar with it but the weight and texture of this rendering produced from this track a series of new pleasures.

 Conclusion

Designer Peter Madnick has designed an uncommonly versatile and fun to use phono preamplifier with a modern, full function, remote controllable feature set. Multiple inputs, voltage and current based MC inputs, a full range of gain and loading adjustments, a subsonic filter and a mono button plus meters there for more than just watching. Made in America build quality is also high and with its wood side cheeks it’s good looking too. The side cheeks are available in both walnut and black finishes:

MoFi MasterPhono BlackMasterPhono in Black

MoFi MasterPhono WalnutMasterPhono Walnut

The MasterPhono’s sonic performance in all modes matches the unit’s attractive looks and versatility. Through all inputs its overall sonic demeanor is on the ever so slightly sweet side, but it never sounded frustratingly soft or warm. Instead, its combination of timbral neutrality, background quiet, deftly delivered transients, pleasing image focus, effective, stable imaging and generous soundstaging and especially its deft balance of all these important phono preamp qualities will let your cartridge’s sonic personality shine.

These days on the Internet some people won’t pay attention unless you scream conclusions like ‘GIANT KILLER!’ ‘YOU WON’T BELIEVE YOUR EARS’, ‘IF THERE’S ANYTHING BETTER I HAVEN’T HEARD IT (AND I’VE HEARD FOUR PHONO PREAMPS IN MY ONE YEAR REVIEWING CAREER)’, ‘A GAME CHANGER!’ or ‘NO NEED TO SPEND MORE, THIS IS AS GOOD AS IT GETS’, but I don’t do that.

You will believe your ears and your ears will tell you this is a well-balanced, honest and “musical” sounding phono preamp that you’ll immediately appreciate and are not likely to get tired of for a very long time if ever. There are better sounding phono preamps, but you’ll have to pay a great deal more to get what makes them so.

I’ll conclude with: The made in America MoFi MasterPhono is among the most versatile, easy and fun to use phono preamp available today and it’s also among the most pleasing sounding for its price and well beyond. Highly  recommended. Includes 60 day money back guarantee through Music Direct

Features:

Fully discrete from input to output

Single ended RCA and Balanced XLR output

Switchable Gain 40db/50db/60db/70db

Passive RIAA using NOS polystyrene and polypropylene film/foil capacitors

Standard signal input via RCA & XLR (Voltage Input)

10 position loading adjustment, including "Custom" via RCA plug

"Current input" via RCA or XLR for low source-impedance phono cartridges

Stereo/mono switch, High pass filter switch

Left and Right meters for output monitoring and calibration purposes

Cascaded voltage regulation stages for lowest noise

Dual-chassis construction isolates power supply and audio circuits separately

Software upgradable via USB to add new updates and features

Specifications

Input: Current mode & Voltage mode, balanced and unbalanced
Gain: Selectable gain for MM or MC 40db, 50db, 60db, 70db
THD:
   10mV@1KHZ MM low: 0.005% A-Weighted
   10mV@1KHZ MM high: 0.005% A-Weighted
   1mV@1KHZ MC low: 0.010% A-Weighted
   1mV@1KHZ MC high: 0.013% A-Weighted
Loading: 15 Ohms, 30 Ohms, 50 Ohms, 75 Ohms, 100 Ohms, 500 Ohms, 1K Ohms, 10K Ohms, 47K Ohms+150pF, & "Custom"
Output Impedance:
   Balanced: 230 Ohm
   Unbalanced: 115 Ohms
Max Output: @1% THD, 10 Volts RMS
RIAA Accuracy: +/-0.05db
Frequency Response: 10Hz – 50KHz +/-0.20db
S/N ratio (20Hz-20KHz):
   Balanced MM: 85db, 93db
   Balanced MC: 81db, 85db
   Unbalanced MM: 75db, 83db
   Unbalanced MC: 69db, 75db
Dimensions: 17.5" x 3.5" x 15.75"
Weight: 15 lbs.

Manufacturer Information

www.mofielectronics.com

MoFi Electronics

1811 Bryn Mawr Ave.

Chicago, Ill.

Comments

  • 2023-08-18 05:23:35 AM

    Anton wrote:

    Yowza!

    I’ve been saving up for either the Luxman 5 input or Mu Fi Nu Vista….now this!

    I wonder if I’d get any credit for all the One Steps I bought.

    Great review! It created ‘want it!’

  • 2023-08-18 07:38:02 AM

    Andrew Curtis wrote:

    Spunky looking

  • 2023-08-18 07:44:12 AM

    Tim wrote:

    I heard it converts analogue input to DSD for processing..

    (jokes)

  • 2023-08-19 08:51:36 PM

    Jim Shue wrote:

    Michael, excellent review! How does this compare to the PS Audio Stellar Phono you reviewed favorably a few years ago?

    • 2023-08-21 03:37:16 PM

      Michael Fremer wrote:

      I'd be lying if I gave you a definitive answer. That was a few years ago and I didn't have the Stellar here to compare to this. However, the Stellar I believe is out of production now that Darren Myers has moved on from PS Audio to Parasound. The MoFi comes with a 60 day satisfaction guaranty (at least it does from Music Direct) so you can't go wrong getting one and giving it a listen for a month or two

      • 2023-11-21 10:44:29 PM

        Steve Ericson wrote:

        The Stellar is on sale at PS Audio at the moment for $1,999.

  • 2023-08-26 11:31:49 PM

    JuzDisGuy wrote:

    Excellent product. Too pricey for me but would still love to own it.

  • 2023-08-27 11:01:13 AM

    Marco van Schoonhoven wrote:

    That electrical balancing is quit interesting... Correct me if I'm wrong:

    With a regular electrical Azimuth measurement a comparison is made AFTER you adjust the ref tone on the meters of equipment used to produce same output on that track 1 of AP test record and then L vs R, R vs L and your looking for the minist output on both channels, try to get both into balance, and that gives you max channel separation (I use a T-100 for that) And with each azimuth correction you readjust the 1kHz test tone to produce the same output on meters and redo that excercise

    So here it is the adjustment of the meters not on equipment but by only changing the azimuth on arm without going further and do the L/R, R/L test? (which you can still do, it also has a VU function, so...)

    I always found that the downside of electronic azimuth measurement is the fact that the final result does not guarantee that the stylus is in perfect position in the groove (despite many think that this is what electronic measurement does, it does not), its basically only aligning the generators to the groove walls, and although that should result in a perfect stylus position, in reality its more not then is...

    After measurement and azimuth corrections, its still advisable to use some sort of view magnification to confirm the stylus is positioned correctly... And up to a small margin from off, you could accept that however it is preferable to have the stylus in correct position over the generators aligned to groove walls...

    And: lets say that with the 'regular' L/R and R/L measurements, on one channel you measure -40dB and on the other -30dB, if left in place, that would be a max of 30dB channel separation, correct? And you might only get to 32dB when starting fiddling around with Azimuth and that is (acc. to what I've read) still beyond the 25dB which we as humans experience as total channel separation so not really necessary to achieve that...

    Ever since announced I was looking out for the moment it came out. A comparison between Elac PP2 and this one would be interesting... same Peter Madnick and to what I've been told a few similarities in design... (not on the outside though) Since I'm looking for the possible 'last phono stage I will ever buy' (it does not really have to be, but that's the criteria I do use to get my next one) this one did showd up on the radar... Here where we live this is the “luxury” level, way above “entry level.” Thanks for that review...

    • 2023-08-28 12:56:02 AM

      Michael Fremer wrote:

      The design scheme in terms of functionality are pretty much the same between the ELAC and this but Madnick says the circuit is very different. Physical azimuth “perfection” is no guarantee of correct azimuth setting… for maximizing separation and balance…however some suggest having the stylus sitting perfectly in the groove is more important….

      • 2023-08-29 05:22:47 PM

        Marco van Schoonhoven wrote:

        Its always a bit of defining the acceptable... Quit obviously a stylus not sitting correct in groove after set the max channel separation (to spec) would result in a return of the cartridge... the stylus should not be too far of from a correct stand-up position otherwise you could be ending up damaging the record... correct? Years back I showed you some pictures of a well respected Japanese cartridge manufacturer in which there was as much as 6 degree off from 90 after electronic azimuth setting (and that one went back, in fact 3 more times after that)

  • 2023-08-28 04:34:23 PM

    Brian Weeks wrote:

    Michael, I was curious if you were able to get the backlight brightness to adjust as described. I took delivery of a MasterPhono last week and cannot get it to work. I have contacted MoFi and am awaiting a reply. Thanks!

    • 2023-08-29 04:33:44 PM

      Michael Fremer wrote:

      please email me at michael@trackingangle.com and I'll connect you with Peter Madnick and he will answer your question. I didn't try to adjust it. Probably should have, but I was ok with it as delivered....

    • 2023-09-04 05:05:30 PM

      Brian Weeks wrote:

      Update: Michael put me in touch with Peter who was very helpful in solving my issue.

  • 2024-01-23 04:03:55 AM

    John B Parks wrote:

    Great review Michael, and a general thank you for your honest analysis and advice over the years.

    Currently, I'm using a Yamaha C-65 preamplifier with MM & MC inputs with selectable loading for both. Yes, this an old piece of equipment; manufactured 1986-1989. To save space I won't list all the specs for the phono section as they can be found online, but it's it is worth sharing the MM selectivity has 3 settings: 2/47kohm200pf, 47kohm300pf, 47kohm220pf, 100kohm. The MC selectivity has just 2 setings: Ikohm & 100kohm. Signal to noise is 90 (MC) & 95 (MM) messured with IHF. The bottom line to my ears is a pleasing warm/neutral sounds phono section. I use this preamp unconstitutionally though. I only use it as a phono preamp sending its outputs to my main front end preamp. This enables me to adjust the volume control of the C-65 as needed for gain control.

    Recently, I've been been considered a dedicated phono preamp. I have a few to choose from. The top choice would be quite a reach at $18,000; The Allnic Phono Stage H-5500, or some other model in the Alnic line. These preamps, you may know, are tupe preamp. I haven't yet reviewed their entire lineup.

    The step-down from the Allnic is the Mofi Refrence. And the step-down from the Mofi is the Tec PE-505.

    I wonder whether you have had or will have an opportunity to review the Tec PE- 505. Without extending the length of this already lengthy comment, comparing a few features of these pramps provides the user with interesting options. Some are or may be advantages, one over the other, depending on the compromise one is willing to forgo.

    Off the bat, the Tec offers a unique de-mag function, but only provides one input while the Mofi has three. While the Tech goes for $2,090 the Mofi is more than double the price at $6,000.

    Years ago I had my sights set on an AudioResearch phono preamp, but made a workable compromise with my unconstitutional us of the C-65. But here I am again opening the door to at least considering a dedicated phono preamp or two. If my decision were solely based on money the compromise is obviouse but with the unique advantage of using the infinite volume control, not to mention the tone controls (sparingly) of the C-65. I wonder, could this be the biggest advantage, for me at least, over these seductive phono preamps?

    Thanks for reading.