Review: Marantz PMD-300CP Cassette Tape Recorder

Mike Rivers

After having this cassette deck around for a few weeks, I moved all my notes,

test data, screen shots, and photos from the workshop to the writing office and

sat down to a blank screen thinking about how I could start this review. I came up

with three ideas: I could give you a description, tell you what it sounds like and

how it works, and verify its specs. I could dive right into my “Trust But Verify”

mode and explain the various lab tests I performed on it, leading into a detailed

discussion of how the test results agreed or not with the published specs and

how they help to explain how it sounds. But I decided that the best place to start

is to address the problem for which this cassette deck is a potential solution.

The Problem

Unless you’re part of the culture (or more likely, the cult) that has a special

fondness for the sound of cassettes, you might wonder why anyone would be

interested in buying a new cassette deck in 2019. You probably haven’t listened

to a cassette in years, or maybe you’re young enough never to have been

exposed to the medium at all except in on-line discussions about how horrid they

sound, which often dovetails with a discussion about how horrid MP3 files sound.

Musicians and music lovers who came of age between the mid 1960s and up into

the ‘90s are the ones with the problem. You know that box of cassettes in a

closet that you haven’t listened to in more than 20 years, but you never had the

heart to throw them away? Nostalgia catches up with you and you wonder if

there’s any good music there – after all, you must have enjoyed it at one time.

Perhaps there are recordings of your high school or college bands, “car tapes,”

or pre-recorded cassettes of hit albums that you loved and never got around to

getting on CD. There might be recordings of concerts you attended or favorite

radio programs, or some family history like grandpa telling stories or playing the

accordion. You have the cassettes, but your last cassette deck, working or not,

went to Goodwill or the dump years ago. Or you rescue that forgotten player from

the basement, only to discover that it no longer works. Long periods of idle time

take a toll on the mechanical tape transports.

In June of 2018 I attended a three-day workshop on audio and video archiving,

restoration, and preservation. While much of the focus was on the technology of

playing obsolete media like cylinders and lacquer disks with the surface flaking

off, there was plenty of attention paid to analog tape. The focus there was both

on preservation of historically important recordings and re-releasing near-

contemporary major label material as means to make new money from old

projects. Those are expensive projects that are usually funded by grants or the

record labels that own the masters. But a few of us got to talking after hours

about “the rest of us” with personal collections of recordings, too long dormant,

that may have some personal or even historical value. These analog tapes, reel-

to-reel or cassette, rarely have sufficient tangible value to warrant paying a

professional to transfer them to digital media, but wouldn’t it be fun to enjoy them

again, and perhaps share them with others, let your kids or grandkids hear the

music you played when you were their age, or maybe even put a few of your

original tunes up for grabs on your Facebook page.

So, to get started on your archive digging, you need a cassette player. Ten years

or so ago, it was easy to find a working one in a thrift store for twenty bucks or

less. While it might be a bit worn and not up to its original performance specs, it

would work well enough for you to assess your collection. Those days are pretty

much gone, though. While you can still find used cassette decks for sale on eBay

or Reverb.com, on a recent browse of the sales, mostly what I saw were high

grade models selling for near-new prices of $500 to $2,000. I own a working

broadcast-quality workhorse TASCAM 122 Mk2 which, despite its nearly 30

years of age, I’ve managed to keep in decent working condition with love, care,

and a shop full of tools and test equipment. To keep it company, there are three

non-working, fairly high-grade cassette decks on my shelf of things too good to

throw away that maybe I’ll fix some day. Yeah, right!

A couple of months ago, a friend came to me for advice about digitizing a couple

of hundred cassettes. She’s a blues collector, documenter, and performing artist,

and wants to start a new project in which she wants to use material from these

recordings. Much of this collection is oral history – interviews and stories from

friends and family members, along with music casually recorded in living rooms -

not up to “release quality,” but valuable for its content. She no longer has a

functional cassette deck and wanted to get one suitable for her digitizing project.

She’s not a techie so I thought it would be best to buy something new rather than

take a chance on a used machine.

Cassettes aren’t a branch of recording technology that I keep up with, so I went

in search of something to recommend and I was shocked to find how few new

cassette decks are on the market today. I was able to find only two new models

that seemed worth considering, the Marantz PMD-300CP ($150) that I’ll be

reviewing here, and the TASCAM 202mkVII ($500). Given the price differential, I

decided to take a look at the less expensive Marantz first to see if it would be a

good recommendation for budget-minded friends and clients.

The Marantz name and trademark has a long history of top quality products in

the hi-fi field, but it’s been bounced around from company to company in recent

years and Marantz Professional is now under the InMusic brand umbrella. It’s in

pretty good company, with other brands you’re likely familiar with – Akai

Professional, Alesis, Denon Professional, M-Audio, Rane, and, among others,

the ION brand of low cost consumer grade home audio equipment. Here I

discovered another budget priced cassette deck, the ION TAPE 2 PC, which, for

about $30 less, appears, from the web site photo and specs, to be identical to the

Marantz Professional PMD-300CP. It’s been around since 2015 and appears to

be out of stock everywhere, so perhaps ION simply decided to revive it under a

new brand and name.

What It Is, and Isn’t

OK, so let’s get started with the review. The Marantz Professional PMD-300CP

(“Marantz” or “300CP” for shot) is a two-deck cassette player/recorder that

follows the form and function of many others that have come and gone. Deck A

on the left is playback-only, while Deck B on the right offers both playback and

recording. There’s a convenient cassette-to-cassette dubbing feature should you

desire to preserve and enhance the low-fidelity qualities of the cassette medium.

For extra-lo-fi and saving time, it will copy a tape at double speed. I did check out

the recording capability, though if your project is to digitize tapes, think of the

second deck as a backup for when the first deck wears out and you still have a

batch to go.

A key feature of the 300CP is plug-and-play cassette digitizing with no additional

hardware except a computer. A USB-A cable is included, along with a download

link to a very simple recording program, making this a very attractive package for

those with a closet full of cassettes and little or no knowledge of computer audio

interfacing. Whichever deck is used for playing the tape will be fed to the USB

output. I found no significant difference between Decks A and B, not surprising

since both transports appear to be identical except for an erase head on Deck B.

The rack ears are included, but are packed separately, along with screws to

attach them, should you want to rack mount the recorder.

The rear panel is pretty sparse - RCA jacks for input and output, a USB-B socket,

and a record level control to adjust the signal level between tape playback and

the A-to-D converter. Since tape levels tend to be all over the place, it’s an

important control for optimizing the level of the digital recording.

Overall dimensions are

16½”W x 8½”D x 5¼”H.

It’s quite a lightweight

according to my kitchen

scale - 7 pounds, 4

ounces without the rack

ears. When it comes to

electromechanical devices, I find that weight is often a fair indication of quality.

Given that my TASCAM 122mk2 weighs in at 16 pounds, 10 ounces, I was on

my guard when checking out the Marantz.

The LED meters have six segments, four green and two red. They display the

playback level when playing a tape in either deck, and the record level when

recording on Deck B. The first segment

 



turns on with the power switch and

remains on, serving as the pilot light and not really a level indicator.

The Noise Reduction switch engages a decoder for playback. All but the oldest

and crudest cassette decks offer Dolby B noise reduction, and when Dolby C

came along, it was included as a choice on better grade cassette decks. Since

the 300CP has no Dolby B/C switch, I asked Tech Support about it. Dolby no

longer makes the encoder/decoder chips that were standard (and the only way to

use the Dolby name and trademark) during the long run of cassette deck

production, so Marantz had to come up with a substitute. I didn’t test this

extensively, but it appears to be reasonably accurate with the couple of Dolby B

tapes I tried. Without going too far astray here, I’ll tell you that it’s all too common

to find Dolby-encoded tapes in a collection that aren’t annotated as such. If you

flip the Noise Reduction switch in order to decide whether an unmarked tape is

Dolby or not, intuition will usually lead you to leave noise reduction off in

playback because it sounds brighter that way - and you could be wrong. This is a

problem high on the tape archivist’s list.

The first thing I did after unpacking the deck was put it on the bench, fire it up,

load up a nicely recorded cassette that I knew pretty well, and started to plug in a

set of headphones to give it a listen. Surprise! There’s no headphone jack!

There’s no end to what cost-cutting a manufacturer will do in order to meet a

price point, and a half-dollar’s worth of parts can increase the end price by ten to

fifteen times that. Of course the analog outputs can be connected to an outboard

amplifier or powered speakers for monitoring or listening. Still, this might be a bit

of an inconvenience as there’s no on-board playback volume control.

A related quirk is that when recording on Deck B, whether the source is from

Deck A or the analog inputs, the analog outputs are muted. If you want to monitor

what you’re recording (and you should), you’ll need to monitor the USB output via

your computer’s audio outputs.

The Marantz accommodates two different tape types, ferric oxide (standard) and

chromium dioxide (CrO

, sometimes called “chrome”). These refer to the

compounds used to make the tape’s oxide coating (the recording surface). The

two oxide formulations require different bias and equalization settings in order to

obtain optimum performance. There’s a third tape type, metal particle, which this

deck doesn’t accommodate. There are individual tape type buttons, labeled

CRO2, for playback (on either deck) and Deck B recording – in for chrome tape,

out for standard. Most original tape labels include the oxide type so you

determine the proper switch setting, crossing your fingers that the tape was

recorded with the proper setting, and if you’re recording a cassette, set the tape

type in accordance with the label. Cassette shells have notches in the top edge

to indicate the oxide type and some decks have a sensor that detects the oxide

type to set EQ and bias automatically, but on the Marantz, you need to set it

manually.

These are “soft” switches that default to “off” (standard) on power-up. The

appropriate author-thing to say here is “Don’t ask me how I know this” so I’ll tell

you. I was making some measurements with a chrome tape and was puzzled by

unrepeatable results until I noticed that the CRO2 indicator LED was off after

coming back to the bench after powering down for lunch.

There’s a tape position indicator. It’s a counter rather than a time display, and it

only functions for Deck B. It doesn’t provide sufficient resolution to cue up a song

in the middle of the cassette, but will get you in the ballpark. For no particular

reason, I gravitated toward using Deck A for most playback, and it would have

been useful to have the counter active. A dime’s worth of parts could

automatically switch the counter to the deck in use, with a default to one or the

other when copying a tape.

A few words about the digital USB output: The converter (actually classified as a

codec) is a single IC, a Burr Brown (TI) PCM2900C, combining a 16-bit converter

with an internal USB2.0 interface. It’s clocked from the USB stream, and

operates at either 44.1 or 48 kHz sample rate as set by the recording program.

It’s a class-compliant audio device and it requires no special driver for Mac or

Windows operating systems. I tried using the almost-universal Windows ASIO

driver ASIO4ALL, which didn’t recognize the device. The chief benefit of using an

ASIO driver is lower (and adjustable) latency, which is unimportant for playback.

Marantz’ goal was to make digitizing tapes simple for the non-tech user, and

that’s what you get.

Although the PCM2900C is bi-directional (it’s a D/A converter as well as an A/D

converter), you can’t use the Marantz as an audio interface. The analog inputs go

only to Deck B, with no signal path from the analog inputs to the USB output.

On the practical side, the noise and distortion in the digital signal path is better

than a cassette will ever be, so there’s nothing lost with the “CD quality”

digitizing. I would prefer 24-bit resolution, though, so I could be more

conservative when setting the digital record level. Furthermore, if cleaning up the

digital transfer is in your plans, some software processing tools work better with a

higher resolution file, and at 2x sample rates. Bottom line - the USB digital output

is for convenience. If you plan to do some serious rescue work on your

recordings, I’d suggest using the Marantz’ analog to feed an outboard computer

audio interface for flexibility in setting sample rate and resolution. But remember

that the best interface money can buy won’t get you a better digital copy than

what comes out of the tape deck.

Under The Hood

There isn’t a whole lot of there, there – the two tape transports, a power

transformer, a fairly sparsely populated main circuit board, the front panel board

with its switches and meter display, and a small digital board for the analog-to-

digital-to- USB conversion.

Decent quality Chinese-made components populate the cleanly laid out main

circuit board. Circuitry is largely discrete (note the plethora of transistors) with a

couple of dual op-amps and FET switching ICs.

Tape recording and playback electronics isn’t terribly complicated, and today’s

low-noise analog ICs make it relatively easy to achieve a good signal-to-noise

ratio. What’s important is how the circuit and mechanical design are integrated

into the final product. Sometimes, here, cost cutting takes its toll.

The most important part of analog tape deck design (and maintenance, as well)

is to assure that the tape makes perfect contact with the heads and moves

across them in a very precise manner. The PMD-300CP’s transports are pretty

light-duty, built from stamped metal and plastic parts that don’t give a lot of

confidence in this area. It uses a single brushless DC motor with belts, plastic

pulleys, and clutches to drive the capstan and reel spindles.

Note the

erase head

to the left on

Deck B, and

the lack of

guides in the

head area (of

either

transport).

The rather

skinny drive

belts are

evident in the

rear view.

Transport

control

buttons are

mechanical

and feel

rather stiff to

operate, but

they do what

they’re

supposed to

do.

Overall build

quality is

good, fit and

finish are pretty good – things that I’ve come to expect from Chinese factory-

made electronics today. Had Marantz chosen a more robust transport, I expect

that overall performance would have been noticeably better, but I understand

how that would affect the price. In the field of consumer and even some pro

audio products, there are always decisions about component choice, and some

are made with cost in mine. The engineering department might be able to sell the

marketing department on spending an extra dime for a low-noise version of an

IC, but not an extra $25 for a tape transport with a robust cast frame and

machined guides.

In Use

To be honest, I haven’t listened to a cassette in probably 10 years other than in

the car or when making a digital copy for a friend or client, so I started out by

conditioning my ears. I picked out a cassette copy of a recording that I made of

one of The Newgrass Revival’s last shows in 1989 before disbanding. This copy

was made on my (now defunct) Sony TCM-5M, a high quality portable cassette

recorder, as a secondary backup to a DAT. I loaded it into my TASCAM 122 Mk2

deck, hit Play, and sat back to listen. I was actually rather impressed - it sounded

better than I thought a cassette could sound. Good cassettes can sometimes

sound pretty good when recorded with good equipment.

Then I loaded the tape into the Marantz, started it playing, matched the level to

the TASCAM playback as best I could using an SPL meter, and thought “gee,

this sounds like a cassette” – overall not as good as when played in the

TASCAM. The Marantz wasn’t missing any highs or lows, it wasn’t clipping, nor

suffering from audible wow and flutter, and didn’t have the brittle sound of high

order harmonic distortion, but it was missing some clarity. Not horrid, but not

impressive like the TASCAM. I thought that what I was hearing could be

intermodulation (IM) distortion, a form of distortion that I can’t immediately

recognize by ear.

Turning to what I expect to be its likely application - digitizing a cassette

collection - I connected the USB port to a computer (Windows) and, just as

advertised, it was promptly recognized as an audio playback device. With the

idea in mind that I might want to recommend this cassette deck to someone who

had a digitizing job ahead but didn’t have any experience with computer

recording, I fired up a copy of Audacity, a free and very capable recording

program that I’d recommend to a novice on a tight budget.

I copied about half an hour of the Newgrass Revival tape to the computer, then

rewound the tape and started both the Marantz and Audacity playing in close-as-

I-could-get-it sync. Switching the monitors back and forth between the analog

playback from the Marantz and the output from my shop computer’s interface, a

Mackie Satellite, they sounded very much alike. I attributed the occasional

difference to the fact that cassette playback is never exactly the same twice due

to its mechanical nature, while the digital playback is completely repeatable. I

have no quibbles with the Marantz’ digital output, except on general principle that

it’s only 16-bit at standard sample rates.

The rear panel playback level control is a very worthwhile addition. Since it’s in

the audio path ahead of the A/D converter, by watching the recording program’s

meters, the digital record level can be set properly to avoid clipping while keeping

a healthy program level. I really wish they had put it on the front panel, however. I

fear many users will ignore it, ending up with either clipped or wimpy digital dubs.

It could be ganged to the front panel Record Level control, with the same knob

used to adjust both the digital (USB) and analog (Deck B) record level, whichever

you’re using. This would be a good update if there were a Mark 2 version.

Knowing that there will be some users looking for a no-brainer solution to digitize

their tapes, I downloaded and fired up the EZ Vinyl/Tape Converter application

that’s offered for the PMD-300CP. It’s the same program that ION provides with

other audio products such as their USB turntables. The Windows version saves

recordings as WAV files only, while the Mac version gives you a choice of

several compressed formats (MP3, AAC, etc.) as well as WAV. Instructions are

included for using iTunes to convert WAV files to other formats.

This program is really simple and straightforward, with the only one option –

recording a tape from beginning to end in a single file, or splitting the recording

into individual files when the program detects a period of silence. This could be

useful when transferring a tape of a record album, though it may be more of a

nuisance if the material is a live show or spoken word. With automatic track

splitting turned off, you can split tracks manually while recoding by clicking a

button in the program. The program does what it claims and it’ll work fine for the

user who just wants to make a digital transfer and doesn’t plan to get any more

involved with computer audio production.

Recording from the analog inputs to Deck B is straightforward. The front panel

REC LEVEL control allows you to adjust the record level using the meters as a

guide. This control and the meters work whether the recording source is Deck A

or the analog inputs. The DUBBING button internally patches the output of Deck

A through the record level control to Deck B. The HI SPEED DUB button doubles

the speed of both transports for double-speed copying. I only tried this to verify

that it worked and didn’t make a critical comparison between the original and the

copy.

Recording Levels

A ¼” half-track analog tape

deck running at 15 ips is

typically calibrated for 1 to

3 percent THD at the

reference fluxivity indicated

by 0 VU on its meter.

Reference fluxivity,

expressed in Nanowebers

per meter (nW/m), is a

measure of the strength of

the magnetic field of the

record head when fed with

a standard signal level.

The original Ampex

standard is 185 nW/M,

though with the

improvement in magnetic

tape, higher flux levels,

which improve signal

-to-

noise ratio, can be used. In

the latter years, a reference

level of as great as 6 dB

higher than the Ampex

level was common.

A narrow track cassette

running at 1-

7/8 ips distorts

very badly at elevated flux

levels, though for the sake

of providing a good signal-

to-noise specification, the

Standard IEC/DIN

reference fluxivity for

cassettes was established

as 250 nW/m.

When playing a reference

tape at standard level, the

Marantz meters just tickle

[-3 dB] segment, where the

analog output level is

-10 dBV, the common

“consumer” operating level.

THD measures around 8%

on playback, which is why:

(a) When recording to tape,

you should keep the

meters

below –3 dB, and (b) Why

a “hot” tape played on this

deck will probably sound

distorted.

One gripe I had with operation, and this is clearly a personal bias, is that I just

couldn’t get my brain to accept a PLAY button at the left end of the transport

controls. I’ve spent too

many years using tape

recorders with the PLAY

button near the middle of the controls and the REC

button safely out of reach of a careless finger. I’d

probably get used to it after copying 100 cassettes or

so, though force of habit had me hitting STOP instead

of PLAY, usually ejecting the tape. Another minor gripe

with the transport controls is that the buttons require

quite a bit of force to operate. I had to put a hand on

the case when pressing the PLAY button in order to

keep the deck from sliding across the top of the bench

I was unable to take a good photo of the meters in

action, but here’s a close-up of the Marantz stock

picture. The leftmost

 



segment serves only as a

power indicator and is always on, leaving five steps of

metering. When recording to tape, the last green

segment, [-3 dB] is as high as you ever want to go.

When the level reaches the first red segment, [0 dB],

THD (total harmonic distortion) is greater than 10%.

This isn’t the “warm analog tape sound,” rather, it’s the

“crappy cassette sound.” Use the REC LEVEL control

and pay attention to the level when recording on to a

cassette! See the sidebar for the geeky explanation of why recording levels are

important.

The bar at the upper right corner of the display illuminates red when Deck B is

recording. The four bars at the bottom of the display panel illuminate when the

CRO2 switches are engaged, and when the normal or High Speed DUBBING

mode is engaged.

The Gory Technical Details

When I write a review, rather than paraphrase the manufacturer’s sell sheet that

you can read on their web site, I fire up the test equipment and compare my

measurements with both the published performance parameters and what’s

reasonable for the device I’m testing. One of the basic tools for measuring an

analog tape decks’ performance and adjusting it for best performance is a

reference, or calibration tape. My cassette reference tape is 30 years old, so any

measurements that I make with it need to be granted some wiggle room to

compensate for the tape’s wear and degradation. When a measurement seemed

questionable, I duplicated the measurement on my TASCAM 122mk2 using the

same calibration tape to validate (or not) the results.

Frequency response as measured with the calibration tape was ±2.5 dB from

30 Hz to 15 kHz with a 2.5 dB rise at 30 Hz and a 2 dB drop at 15 kHz. The two

channels tracked within 0.5 dB. This is quite good considering that a new

calibration tape would probably play closer to flat at the high frequency end of the

range. It’s not unusual to find a low frequency hump when using a calibration

tape due to the magnetic field fringing effect. It occurs when recording, too, and,

while there’s sometimes a low frequency equalization adjustment, it’s rarely

perfect. This rise around 50 Hz adds some extra oomph to the low end, often

desirable when recording certain kinds of music – “analog warmth,” you know.

Frequency response tones on the calibration tape are recorded 20 dB below the

250 nW/m reference fluxivity level so as to avoid making measurements with

“tape compression,” a different anomaly that’s loved by many engineers.

Recording tones on Deck B and measuring the frequency response of the

playback yielded results quite similar to the calibration tape playback with

exception of the low frequency behavior. Here, there was about a 2.5 dB dip at

around 60 Hz where the calibration tape showed a boost around 50 Hz. To be

consistent with the playback frequency response measurements, I recorded my

test tones at the same level as the calibration tape. With the same head used for

recording and playback, the low frequency fringing effect should be minimal, so I

suspect that the dip around 60 Hz might be due to AC line frequency hum being

recorded and then partially cancelled by residual AC hum in the playback

electronics. There’s a fair amount of line frequency hum that I’ll address further

on.

When it comes to noise, a bulk-erased tape plays back at about –50 dB

referenced to the maximum output level. The output is muted when a tape isn’t

running, so quiescent noise when stopped is essentially zero.

Distortion measurement was tricky. I have two hardware distortion analyzers, an

old Hewlett-Packard 334A and a relatively modern NTI Minilyzer ML1. For

record/playback at the –20 dB record level, the H-P measured around 0.05%

THD, which seems unrealistically low. The Minilyzer measured 6.5%, which

seemed unrealistically high. THD (not including noise) calculated from the

amplitude of the 2

and 3

harmonics read off the spectrum plot of the 315 Hz

test tone at 250 nW/M comes to around 1.5%, which is a bit above the

manufacturer’s stated THD of “<1% @ 1 kHz” but believable and not

unreasonable.

Since the frequency response and THD seemed acceptable, I started looking for

what made the Marantz not sound as good, when playing music, as my reference

TASCAM. I looked at the Marantz’ output with a spectrum analyzer and that’s

where things got interesting. Here’s a spectrum plot of the 315 Hz tone on the

calibration tape, using Sound Forge along with the spectrum analyzer plug-in

SPAN from Voxengo Software:

Great Googly Moogly! Look at all that garbage!

In a perfect world, the big spike at 315 Hz sould be the only pronounced peak

present in the spectrum, but nothing’s perfect. The 60 Hz AC power line

frequency is visible here, along with several of its harmonics. I’ve annotated the

and 3

harmonics, but they’re visible above the noise floor up to around the

harmonic. Given that this 315 Hz tone is recorded near maximum level, some

harmonics are to be expected, however, there are also spikes at frequencies not

related to either the AC line or test tone frequencies. Most of this spurious noise

is 40 dB or less below the level of the test tone, but it all contributes to the

THD+N figure.

For comparison, here’s a shot of the

same tape played on my TASCAM

122mk2 deck, which measures

substantially lower THD+N than the

Marantz. This plot is zoomed in to

show more detail where it matters. The

overall noise of floor of the TASCAM is

10 dB lower than the Marantz, and

only the 3

and 5

harmonics of the

test frequency are of significant amplitude. Cleaner spectrum equals cleaner

sound.

So where are all those spurious frequencies in the Marantz coming from? And

how much do they matter? The relatively clean TASCAM spectrum demonstrates

that they aren’t coming off the tape, so to eliminate the tape from the Marantz

measurements, I used a tool called a “flux loop.” It simulates the varying

magnetic field as a

recorded portion of

tape crosses the

playback head gap.

This allows testing of a

tape deck’s signal path,

independent of the

heads and tape path.

Other than one that

Ampex sold which

mates perfectly with

the AG-440 head

assembly, this isn’t a

commercially available

tool. The one I use is

home-made, from

about 30 turns of #24

enamel wire wound

around a scrap of

perforated circuit

breadboard material. It’s driven by an oscillator with a resistor in series to

maintain constant current through the coil at all test frequencies. It’s important to

keep the coil in a fixed position while making measurements, hence the spring

clamp you see in this photo. If you one a tape deck, I encourage you to make

and experiment with a flux loop. You can learn a lot from it.

In order to use the flux loop, the tape deck needs to think that there’s actually a

tape being played. In the PMD-300CP, the output is muted until a cassette is

loaded and the Play button is pressed, so with a piece of tape, I fooled the

mechanical sensor that tells the electronics that a cassette is ready to play.

There are a couple of other switches on the rear of the transport chassis that

operate when the Play button is pressed – one un-mutes the output, the other

starts the motor. With everything in place, the coil of wire couples the signal

generator’s output to the playback head and it appears at the deck’s audio

output.

Using the flux loop, I ran a frequency response check in both the standard oxide

and CRO

modes. Because the signal isn’t actually coming off tape, what you

see with a constant amplitude frequency sweep is the reciprocal of the

equalization curve. By using a table of frequency versus amplitude values for the

standard equalization curves, I confirmed that the equalizer section of the

playback electronics is doing its job properly. To avoid distortion in the

electronics, I set the generator level so that at the peak of the EQ curve, the

output level was –20 dBu.

By raising the amplitude of the signal feeding the flux loop and looking at the

output waveform with an oscilloscope, I was able to correlate the recorder’s VU

meter reading with the point where distortion begins. Here’s what a 30 Hz sine

wave from the flux loop at 0 dB on the VU meter looks like at the output of the

Marantz, and

for

comparison,

the TASCAM.

The Marantz

has a lot of

harmonic

distortion at

the lowest

frequencies.

It’s not nearly as horrid looking above about 100 Hz. To put a positive spin on

what looks like substantial distortion, for recordings heavy on the bass (did they

have EDM 30 years ago?) you might actually like the punch that the harmonic

distortion gives it. But it’s still distortion.

With the flux loop setup, I was able to put the Marantz into Play mode without

actually playing a tape, and by jiggering the motor switch, I could look at the

noise spectrum with and without the motor running. With the motor running,

there’s a spike at around 107 Hz, with its harmonics up to around 3 kHz visible

above the noise floor. I’ve annotated the fundamental and its first three

harmonics here. Then I opened the motor switch and all of those spikes went

away, leaving only the power line frequency and a few of its harmonics.

Well, we have an “AHA!” moment here. All of those mysterious noise spikes

going well up the spectrum is coming from the motor. It’s at a low enough level

so that its inaudible on its own, but it contributes to the THD+N measurement,

and provides plenty of frequencies to contribute intermodulation distortion to the

tape playback.

Interestingly, the fundamental frequency of the motor noise follows the speed of

the motor, which is why I said the frequency was “about” 107 Hz. Putting a finger

on a pulley or the pinch roller to put more drag on the motor causes the motor

noise frequency to drop.

Still, the frequency response, noise, and harmonic distortion measurements don’t

suggest why a tape played on the Marnatz PMD-300CP doesn’t sound as good

as when it’s played on my TASCAM 122mk2. When playing the test tape, the

spectrum shows some close-in sidebands around the test frequencies that aren’t

present with when introducing those same frequencies with the flux loop. This

suggests that the sidebands are a product of frequency modulation of the

playback – “flutter,” in common lingo. A certain amount of flutter is present in all

tape decks; in fact some think that this is part of the analog sound that they love,

though in professional tape decks, it can be extremely low.

I’ve been using common and mostly free software tools (Room EQ Wizard, the

Voxengo SPAN spectrum analysis plug-in - Audacity, and Sound Forge) in

conjunction with bench test equipment - but I don’t have a tool for measuring

flutter other than to make a rough estimate from the spread and amplitude of the

spectrum of a single tone.

A web search for a software application that quantitatively measures flutter

turned up only source, the Virtins Technology Multi-Instrument program.

Unfortunately the only version that includes wow and flutter measurement costs

$500, more that I can justify for the little work I do on analog tape decks these

days. However, there’s a fully functional trial version that did the trick, presuming

that you have a speed/flutter test tape (I do – a 3 kHz tone). The program

performs a spectrum analysis of the tone when playing the tape, crunches

numbers, and comes out with a number for both weighted and unweighted flutter.

Here are the Virtins spectrum plots for the Marantz and my reference TASCAM

decks side by side for comparison.

Notice the difference in the width of the spectrum spike and the height of the

widened portion, which represent sidebands surrounding the test frequency

created by speed fluctuations as the tape moves through the guides and across

the heads.

The common flutter specification that you’ll find published for a tape deck (or

turntable, for that matter) is a bandwidth-limited measurement that measures the

amount of frequency deviation, but measures the frequency modulation only up

to 250 Hz. This is the kind of flutter that causes a steady tone like a piano note to

warble. It’s typically caused by bad bearings, a dirty or out-of-round drive wheel,

tape dragging on a reel flange or cassette shell, motor speed variations, or

irregular tape tension.

Unweighted flutter is calculated on the full bandwidth of the detected modulation

frequency, usually up to 5 kHz. It’s typically the result of inadequately supported

tape in the head path, tape scraping on guides, or not making perfect contact

with the head, all of which results in high-speed vibration of the tape in its travels.

This has a special name – “scrape flutter.” It’s the mechanical equivalent of

digital jitter, and has similar audible effects.

The Marantz weighted flutter clocked in at 0.25%, close enough to its specified

“<0.2%,” allowing for the stability of my test tape and the program’s method of

calculation. In comparison, under the same test conditions, the TASCAM’s

weighted flutter measured 0.08%. Unweighted (full bandwidth) flutter, however, is

a different story. Here, the Marantz measured 0.9% while the TASCAM

measured 0.15%.

Having observed and commented previously on the rather lightweight tape

transport design and build, I believe that excessive scrape flutter is what gives

the Marantz playback a tendency toward murky sound.

The Wrap

So here’s the deal. This is an inexpensive cassette deck. Build quality appears to

be decent with the exception of the light-duty tape transports. Unfortunately,

when it comes to tape, the transport is the make-or-break part of the playback

system. This one is OK, far from exceptional, decent living room quality, but

nothing “professional.” I think it’s a good buy for the price as long as you

understand and accept what it is. I expect that most people interested in buying

one will be using it for a DIY cassette-digitizing project. The scope of such a

project can vary widely, mostly with the size of the collection and what you intend

to do with the digital copies. If you’re willing to accept that the playback (and

hence your digital copy) of your cassette won’t be as good as it could possibly

be, you might be satisfied with a Marantz PMD-300CP. But if you have some

high quality cassette recordings, they’re probably worth playing on a better

machine than this.

What it will certainly be fine for, if you have a large collection of tapes that you

haven’t heard in years, is to catalog them. You can listen, at least with one ear

open, while copying them to digital format, take note of any exceptional ones,

and also weed out the ones that you can’t figure out why you ever saved. You’ll

get listenable digital copies, and if you discover a small number of gems that

deserve to be preserved with the best fideleit, you can take those to a

professional.

I can’t guess how the current generation of cassette fans will accept the Marantz

as far as making new cassette recordings. It’s not hi-fi, that’s for sure - it’s

cassette-fi, but it may be sufficiently low-fi to appeal to those in the movement.

That’s not intended to be judgmental, just the best reason I can think of why

anyone would want to record a cassette today. But if that’s what you want, the

Marantz will do it.

I knew pretty much what to expect when I undertook this review, and while the

PMD-300CP didn’t completely disappoint me, I wasn’t enthusiastic enough about

it to keep it for my own shop. Working with it for several weeks was a good reality

check for me. Since most of my analog tape experience has been with

professional-grade tape decks, both cassette and reel-to-reel, working with this

one was a bit of a revelation, and it provided opportunity to dig into the causes for

distortion that’s clearly audible but that you won’t find within published

performance specifications. It’s easy to find reasons for never wanting to deal

with tape again, but you have that closet full of cassettes, and the Marantz

PMD-300CP could be a cost-effective way to preserve them in digital form as

long as if you’re satisfied with the sound of the playback.

What I’d like to see for the purpose is a cassette deck with a well built and robust

tape transport (which the Marantz lacks), and solid electronics to support it

(which, mostly, the Marantz has). It could playback-only, with the cost saved by

eliminating an erase head and record electronics put into more precise

mechanical design and implementation. I think that incorporating the USB

interface is a good feature, as it simplifies the digitizing process for the non-

technical user. I’ve seen sweat break out when I tell someone “Just buy a cable

and connect the output of your cassette deck to the line input on your computer.”

However, I’d like to see higher resolution available for the analog-to-digital

conversion. I suspect that Marantz assumed that users would be making CDs

from their cassettes, so “CD quality” was sufficient, but I there will be a fair

number of users will want to experiment with digital processing to do some

cleanup work, and starting out with a higher resolution file often gets the best

results.

If Marantz or TEAC gets hold of this article, perhaps they’ll consider building a

less compromised and dedicated cassette transfer machine, if it’s not already too

late. If I hear about it, I’ll give it a good workout.

Finally, here are some useful related links:

An article all about flutter, from the too-soon-late Dale Manquen, one of the most

knowledgeable folks when it comes to what makes a good tape deck good.

http://www.manquen.net/audio/index.php?page=17

SPAN from Voxengo Software, my go-to spectrum analyzer. This is a free DAW

plug-in available in formats to work with just about any audio recording program

more advanced than the simple “voice recorder” or “CD maker,” including

Audacity (below)

https://www.voxengo.com/product/span/

Audacity – a fine and free open source and multi-platform (it even runs on Linux

systems) audio recording and editing program for when you want to tweak your

digitized copies of your cassettes. It comes with a slew of tools, many of which

are useful for cleaning up hum and other noises.

https://www.audacityteam.org/

Using A Flux Loop – The original Ampex training document that includes

information about the different equalization curves that have become standards

(and some not-so standard). Make a flux loop and check out your tape deck.

http://www.brianroth.com/library/flux.pdf

Virtins Multi-Instrument – This is the software I used for flutter measurements,

and it’s capable of measuring just about anything about an audio signal. The full

version is quite expensive, though you can have fun with the free trial version

that works for a month. You’ll need test tapes in order to establish playback

baselines accurately, but there’s a lot you can learn even if you have to make

your own test tape by recording and then measuring the playback characteristics.

https://www.virtins.com/multi-instrument.shtml

Standard test tapes – These are expensive but I’m including a good resource for

those not faint of heart or budget. You’ll also find cassette test tapes of varying

quality for sale on eBay.

https://www.gennlab.com/alignment_cassettes.html