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OTARI Products

Shop Otari Products

T/REDS™ - 2" Universal

Replacement capstan and idler rollers for all OTARI MTR-90's & MTR-100
Available Online
Unquestionably the best looking (see below), best performing aftermarket rollers you can buy. Extremely efficient RED thermoplastic elastomer, our rollers are supplied with special soft-tip set screws which allow them to be used with all MTR-90 series (mkI,II,III) and MTR-100 machines.

Additionally, T/REDS are the only replacement rollers which may be safely rotated on the capstan shaft to minimize rotational error and optimize your machine's flutter performance. (wow & flutter analyzer required)

Always in stock & ready to go!
__Photograph courtesy of Simon Buvoli, Camorino, Switzerland
via email:

"We are very impressed with the “Reds” we installed on one of our MTR-90 mkII’s (“Annie”). We have been running ATR tape for the last six months. We installed the “Reds” last week and have received many positive comments on how much better “Annie” (MTR-90 mkII) is handling the super slick ATR tape. The sound has “firmed-up” and seems “much more defined” with the Reds.

Thanks for engineering the best, tape machine replacement components!"

Brett Johnson, Chief Engineer/EIC Audio SMARTruck
Dept. Audio Arts & Acoustics, School of Media Arts
Columbia College Chicago
Chicago, Illinois

__Photograph courtesy of Simon Buvoli, Camorino, Switzerland
via email:

"Just wanted to let you know that I received and installed the T-Reds yesterday and man do they run smooth.

They even handle the thick ATR tape beautifully!! Installation was easy.


Mills (Mills Logan, Nashville, TN) July 2014

Mills Logan is well known for his work, with: Toby Keith, Luke Bryan, Taylor Swift, Travis Tritt, Sammy Hagar, Lonestar, Keb Mo, Art Garfunkel, Sister Hazel, Rascal Flatts, Rodney Carrington, Steve Azar, Ashley Cleveland, James Otto, Clint Park, Collective Soul, Pat McLaughlin, Kenny Rogers, Pam Tillis, Michelle Wright,
Matthew West, Shelly Fairchild, Neal McCoy, and Leann Rimes....

via email:

"Two years ago we purchased a set of your T/Reds for one of our (3) Otari MTR 90 II's. They are everything you said! They still look new, they clean great and I'm definitely a satisfied customer, thanks!

We now have to resurrect another of our Otari's for some transfer work and need another set (possibly 2)...."

Bert Drake, Engineering
Golden Era Productions
San Diego, CA

via email:

"The T-Reds arrived yesterday, and this morning, I finally worked up the courage tov operate on the "tach roller assembly".   In 30 minutes, she was up and running like new!

The new rollers seem to be formulated with just enough 'tackiness' to allow for flawless movement and counter accuracy without annoying adhesion to the tape.  So, there's no more clicking, popping or snapping sounds from the drive (capstan) roller.  No more missing seconds and mis-cues from the counter and autolocator.  Of course, the following has no bearing on performance, but these buggers look really cool up there.

Thanks for all of your help, concern and return messages.  It's great to have someone in your corner when things get ugly and you need some support.


JMM Studios
Metuchen  NJ   08840

T/REDS rollers on MTR-90
Promotional PDF

T/REDS installation PDF

MTR-90 Set-Up PDF

Black/REDS™ 1" (Sorry, no longer available)

Recommended for all DTR-900 & Mitsubishi 1" digital recorders.
Available Online
High performance designed to take full advantage of the higher wind speeds available on the fast winding OTARI & Mitsubishi digital machines.
Black/REDS rollers
Download PDF

Quartz/Pyrex Lifter Sleeves

Available Online
A pair of centerless ground & polished quartz/pyrex sleeves for your MTR-90. Harder than chrome steel means longer life and less wear and tear on your tapes. Guaranteed accurate high speed tracking.

Easy install with provided instructions.

SPECIAL ORDER ITEM: please contact us for information
__Quartz Pyrex Lifter Sleeves___

Replacement Swingarm Tension Springs

Replace old, fatigued springs on your MTR-90.
Available Online
Set optimum, tension and keep it that way. Quality tempered music wire means longer spring life and stability.
Sold as a package of (2)
Swingarm return springs
Download PDF

Motor Driver Power Transistors

Available Online
Replacement power supply and motor driver amplifiers. High voltage and current handling. Our house part numbers - manufactured by ON Semiconductor.
XB2552P (PNP rep. 2SB552)
XD2442N (NPN rep. 2SD552)
MDA transistors

Computer grade electrolytic capacitors for the MTR-90 power supply

Six direct replacement Computer Grade electrolytic capacitors. Metric sized with just enough elevated capacitance and voltage rating for longer life and improved performance.

Made in the USA by United Chemi-Con.

eMail us!
SPECIAL ORDER ITEM: please contact us for information
Power supply capacitors

Capstan Motor Alignment Collar

The cure for MTR-90 high frequency instability.
Available Online
The Alignment Collar locks into the transport's deck plate. Strengthens the motor mounting and makes the capstan azimuth & zenith adjustable. Easy installation w/ no deck modification.
SPECIAL ORDER ITEM: please allow 2-3 weeks for delivery
Try it for 30 days. If you don't agree it's amazing, send it back for a full refund.

"Capstan Alignment Collars for the MTR90's work great,
never thought I could achieve such a perfect tape path! Thanks!"

Greg Snow
Fredonia University, NY

"After spending countless hours and over $2,500.00, with a certain company in San Francisco, our MTR-90's tape path was still far from perfect and I was frustrated. I discovered the Capstan Alignment Collar at the PrecisionMotorWorks website and for a mere $375.00, I purchased and installed the CAC and "TONE DANCE" is gone.

Finally a company made sense... A must have for "the perfectionist".

Sheldon Zaharko
The Factory Studios, B.C., Canada

Capstan alignment cpllar

Servo-Disc Motor Kit for Otari & Mitsubishi professional recorders (Limited availability)

eMail us!
Heavy duty, USA made, direct replacement motor kit for the O.E.M. Yaskawa disc motor (Japan). Superior current handling capacity. Fits all MTR-90 /100 / DTR-900 & Mitsubishi Capstan motors.
SPECIAL ORDER ITEM: please contact us for ordering information
Servo disc motor kit
Download PDF

Head Shield Motors

eMail us!
Direct replacement Head Shield Motors for the OTARI MTR-90.
SPECIAL ORDER ITEM: please contact us for ordering information
Head shield motor
Download PDF

Unitized HardArms™ (Sorry, no longer available)

Don't throw money away on less than the best!
Available Online
Swingarms built right and they won't cost you a (swing)arm and a leg! Engineered for strength, these are as close to being a single, solid piece of metal as is possible. Straightness is guaranteed within .003" end to end in X & Y planes.
Back in stock with plenty available!
HardArms / MTR-90 swingarms
Download PDF

EMC Music Mastering Heads 2" - 24 Track (Sorry, no longer available)

Extended Response. Extended Life. Ultra-low distortion.
We were EMC's exclusive representative & sales agent to the music recording industry. Originally manufactured in San Diego, CA by Mr. Clay Whetstone, unfortunately these fine magnetic heads are no longer produced. Mr Whetstone has retired from manufacturing and we're truly sorry to have lost such a fine product.
Sorry, EMC heads are no longer in production. Please check with us for options.
EMC 2" magnetic heads
Download PDF

Product prices are shown at our online store: Shop_PrecisionMotorWorks

Download: Our recommended MTR-90 Set-up / Alignment Procedure.pdf

Ampex Products

Shop ATR-100 Products

NEW Poorman's Input-Output Calibration & Service Extender Board

A simple, now affordable solution to ATR-100 Input-Output calibration.
Available Online
If you want to get the most out of your recorder, you MUST properly calibrate the input and output electronics. This is how you calibrate and make adjustments to the ATR's Input-Output electronics. All aluminum support and a high-quality circuit board. Supplied with very detailed instructions for setting up your I-O modules.
In-stock & ready to go.
ATR-100 I/O service extender board

Input-Output Module - Front Panel Overlay Kit

Now on Sale at 15% off - Just $85.00/Set

Available Online

A face transplant for your Ol' Buddy. Your old worn out I/O faces can look exactly as they once did - every original detail is reproduced in the engraving. Washable and reasonably scratch resistant.

  • permanent “peel & stick” adhesive from 3M
  • laser engraved (not printed) on super tough 30 mil mylar
  • easy install with provided alignment tools & “foolproof” instructions
Kit includes everything needed to "re-face" two Input-Output modules.

View PDF

MagREELS™ - Precision Auto Centering NAB adapters for the ATR-100 (Sorry, no longer available)

Available Online

Price Reduction!

Think NAB adapters are just for holding reels on the recorder? We are really excited about this new product and we're sure you will be too if you give them a spin. You simply won't believe how significant a contribution MagREELS™ can make to a smooth running machine until you experience it for yourself.

The world’s best tape recorder deserves the world’s most precise NAB adapters.

  • NAB Machined 6061-T6 aluminum alloy. Concentricity & axial runout is less than .003" TIR. Beautifully anodized for appearance and durability in your choice of three colors and laser engraved.
  • Three stainless steel ball detents spaced at precisely 120° provide equal outward pressure of 4-7 lbs at each point, to capture the reels and provide DYNAMIC REEL CENTERING automatically. No clamps to turn or expansion collars. “Snap” the reels on and lift the reels off - it’s really that easy.
  • NAB drive pins (3) are case hardened steel in black “no-rust” finish. You won't find any plastic on MagREELS™ NAB adapters.

Auto-centering MagREELS™ adapters will absolutely:

  • Expedite & simplify reel changes
  • Minimize Wow & Flutter by improving reel concentricity and decreasing the amount of work required of the constant tension reel servo
  • Dramatically improve tape pack at fast wind speeds
  • Add a great high-tech look!

Order the "Basic set" to support 1/4" & 1/2" tape widths. Add the optional .25" spacers with the "Complete set" to support 1" tape and optimize the handling of 1/2" reels.

"I put them (MagREELS) on the day after I received them - my Christmas toys. Wow! Fast rewind tape pack looks almost identical to 30 ips play tape pack and the reel wobble is gone. I would never have thought adapters could make that big of a difference.

Thanks for making these! I'm very happy with them.

My advice to all who run ATR-100's, it's a no-brainer, get yourself a set of MagREELS."

Denny Chandler
Las Vegas, Nevada

"The MagReels are very, very nice.

Thank you!"

Tim Leggett
Houston, Texas

Tape Project Forum
Topic: MDI MagREELs For ATR-102
March 24, 2012, 11:06:25 AM

Hi All,

I just wanted to mention I picked up a set of Jeff Gilman’s MagREELS ATR-102 10½ reel hub adapters and really do like them. I bought the set with the extenders so I can use them with ¼” and ½” reels. They really do center the reels on the spindles and give absolute no slip cogged drive by their design with the pin that slips into the holes in the reel platter. They really stop the reel wobble when the transport is running.

I wasn’t sure if anyone had tried them or posted about them. I really do like them.

Tim Leggett
VPI Aries 3 - SDS - Super Platter - Periphery Ring Clamp - Phantom Tonearm,  Ray Samuels XR-10B,  Benz Micro Glider H2 & Ebony 3H, Antique Sound Lab AQ-1001 DT, Vandersteen 2Ce - Triangle Celius 202, Technics RS-1520, Ampex ATR-102
MagREELS™ NAB in redMagREELS™ 1/4" spacer in black

Info & Specs.pdf


Read the MagREELS review
the April 2013 issue
TapeOP Magazine.

Armrest endcaps for the ATR-100

Available Online
Molded from rugged polyurethane - 75 shore A durometer. These will exactly replace your missing endcap(s) but won't have exactly the same look. So, we sell them in pairs only. You've got a choice of flashy red or traditional black. Replace missing original parts, or get a pair to freshen up the appearance of your machine.
ATR-100 armrest end cap, red
ATR-100 armrest end cap, black

Head Assembly Parts - Upper Limit Guide

Available Online
OEM ceramic parts are no longer available. We needed a durable, cost effective replacement. Our answer is precision machined, non-magnetic stainless steel, plated with a thick coating of heat treated electroless nickel for hardness and long wear. Hand polished for a brilliant and ultra smooth finish.

Slightly larger (diameter) then the original part for secure limit guidance at fast wind speeds, i.e. when the tape lifters are energized.

ATR-100 head assembly, upper limit guide

Head Assembly Parts - Lower Limit Guide/Post

Available Online
OEM ceramic parts are no longer available. We needed a durable, cost effective replacement. Our answer is precision machined, non-magnetic stainless steel, plated with a thick coating of heat treated electroless nickel for hardness and long wear. Hand polished for a brilliant and ultra smooth finish. The base is lapped by hand to "trim" the height of the part to within .000050" of exact specification.
ATR-100 head assembly, lower limit guide

Replacement Control Panel Overlay

The fastest, easiest way to give your ATR-100 a face lift.
Available Online
Instructions plus everything you'll need for removal of the old panel and installation of the new are provided. Permanent factory colors on 25 mil LEXAN.
Control panel overlay
Installation PDF

ATR-100 PC-control panel w/ VariSpeed & Search-to-Cue

A great looking, USB interface for fully controlling your ATR-100 from your PC desktop. Opens on top of your mastering applications and includes a fine resolution vari-speed and search-to-cue all in one compact package. Now, you can have everything you've wanted for your ATR-100 with the convenience of centralized desktop control.
Limited interest in this product idea didn't justify production. Some ideas live on as "concepts" only.
PC Control demo

"Click on" the image for a
detailed "look"...

Capstan with Optical Encoder Assembly (Sorry, no longer available)

Available Online
Simply the best available for your ATR. Guaranteed low flutter <.02% din pk. @ 30 ips (<.015% typical). Our unique , single mandrel production method for grinding and optical alignment of the tach, guarantees the most accurate, flutter free roller you can buy.

and, we'll prove it to you!

Your trade-in is requested.
ATR-100 Capstan

Timer Idler Assembly

Available Online
Guaranteed timing accuracy and concentricity for low flutter. Low noise bearings installed. The best you can buy for your ATR-100.
Your trade-in is requested.
ATR-100 tacho roller

Tape Guide Plates

Available Online
Due to the scarcity of OEM parts, we are now offering our highly polished, heat treated, electroless nickel plated guide plates for your purchase. Exact replacements for the original parts - they look sharp, work great, and they're affordable!
ATR-100 Tape Guide Plate

Complete Tape Guide Assemblies - "ready to go"

Available Online
Complete assemblies are available for 1/4" and 1/2" tape. Hardened, electroless nickel guide plates work great and look sharp. Bearings are appropriate precision class and selected for low noise.
1/4": p/n: ATR.TG.25
1/2": p/n: ATR.TG.50
ATR-100 tape guide - 1/2"

Tape Guide Bearings

Available Online
Precision, low-noise bearings for all rebuildable ATR-100 tape guides.
p/n: 626ZZ.A5.NS
Ball bearings

Non-rotating TFF Scrape Flutter Filters for the Ampex ATR-100

Available Online
Non-rotating, floating, teflon elements with adjustable zenith for accurate tape tracking - extremely low coefficient of friction. As the tape moves across the elements it pulls away molecular level particles of teflon. This process actually serves to "lubricate" the tape path thereby reducing tape shedding.
  • No low frequency flutter component
  • No low frequency noise or "tone" generation
  • Patent Pending
1" - 2trk.(top photo) p/n: ATR.TFF.SFF.1
1/4" - 1/2"(bottom photo) p/n: ATR.TFF.SFF.5
Sold as a set of (2) only
ATR-100 scrape flutter filters -1"
ATR-100 scrape flutter filters -1/2"

Quartz/Pyrex Lifter Sleeves (Sorry, no longer available)

MUCH harder than the common chrome sleeve - longer wear & for less money. Centerless ground and highly polished for accurate tracking. Instructions provided for easy install.
SPECIAL ORDER ONLY: Please check with us.
ATR-100 Quartz- Pyrex lifter sleeves

Molded Accessory Tray (Sorry, no longer available)

a really handy option
Available Online
Exactly replaces the flat, blank panel on the left side of most* ATR-100 decks. Keep pens, edit blades etc. where you need them and out of the tape path! Made by AMPEX and originally offered as an OEM option.
*if the front, left side of of your transport is occupied with optional Search-to-Cue - this item cannot be used.
ATR-100 accessory tray

EMC - ATR series Music Mastering Heads 1/2" - 2 Track (Sorry, no longer available)

Extended Response - Extended Life - Ultra-low distortion.
Call for Info
We were EMC's exclusive representative & sales agent to the music recording industry. Originally manufactured in San Diego, CA by Mr. Clay Whetstone, these fine magnetic heads are no longer produced. Mr Whetstone has retired from manufacturing and we're truly sorry to have lost such a fine product.
"Jeff -

I installed the EMC ATR-100 heads that we bought from you on the ATR that we bought from an eBay seller and while I did have several problems with his machine your heads were perfect. This is our first set of EMC heads and I am very pleased with the results......


Kim Stallings
Sony Music Studios / NYC"
Sorry, EMC heads are no longer in production. Please check with us for options.
EMC magnetic heads for ATR-100
Informational PDF

AMPEX ATR-100 O.E.M Maintenance & Shop manual

Available Online
THE ORIGINAL - taken from the LAST, published version. Provided as a searchable PDF on CD or Download (155mb).
p/n: downLoad: ATR.100.MANUAL.PDF_DL
ATR-100 Shop Manual

NEW EZ Tilt-Locks for the ATR-100 pedestal stand

Available Online

Setting the tilt angle of the ATR-100's console is important for ease of use and servicing. Locking it in place is even more important, particularly when moving it and the OEM pedestal stand.

These wing-head screws are machined at the ends to fit precisely in the locator holes, providing security and the ability to easily change the console angle without the need for that Allen wrench which you can't find most of the time....

Lot's more for the ATR-100 at our online store!

Tools for the Tape Path

Shop for Tools

NEW - 6" capacity Digital Caliper - SAE/Metric

Compare ours to calipers costing twice as much.
Available Online
  • Instant push-button conversion SAE/METRIC
  • Stainless steel construction 
  • Resolution to .0005" / .01mm
  • Accuracy guaranteed to +/- .001
  • "Auto Shut-Off" after 10 minutes of inactivity
  • Supplied in fitted, cushioned plastic box - includes (2) batteries
  • Made in Taiwan - calibrated in the USA

If you're running analog machines, you know you'll need parts from time to time. Figuring out what you need is often about describing the part with accurate measurements. Here's a very repectable tool for the job at a super price.

NEW - 34 piece Micro Tool & Driver Set

A handy set of often needed miniature drivers.
Available Online

Flat, Phillips, Torx, & Allen drivers plus a small magnifier and a couple of really neat extenders - including a flexible extender to get into some really strange places. Not a set you'll use every day, but when you need it, it'll be ready. Can't go wrong for the money!

Supplied in fitted plastic case. Made in Taiwan (not China)

NEW - NON-MAGNETIC Tape Path Alignment Reference Bar

A must for tape transport alignment.
Available Online
Ultra-Precision, machinist-type parallel bar. For gauging & setting tape path & head alignment. USA machined in our shop from high quality, flat ground, cast aluminum tooling plate and guaranteed flat/parallel on all six sides to within .0005". Non-magnetic and stable for long lasting accuracy, yet, "soft" enough to avoid damage to sensitive tape path components. For use on most 1/2" - 2" tape transports.

Cautionary note: metal laminated heads are VERY soft, so it is wise to cover the head gap with a strip of 1/4" or 1/2" splicing tape only. This will reduce the possibility of any surface damge. When completed, clean (with HR&R) and demagnetize the heads.

Generally available from stock, but please allow up to 1 week for delivery
Head alignment tools

Tape Path Gauge Block for Set-up of MTR-90 tape path

Available Online
Gauge Block designed with 1/2" tool steel base for stability and rigidity, enabling accurate set-up & maintenance of tape path height & parallelism. An amazing tool for problematic MTR-90 transports.

Rental unit is available. (USA only)

Transport alignment tools
Download PDF

Precision Spring Scales

Available Online
Swiss made, quality scales with "Zero tare", for setting critical tape path tension. Available in a wide range of values. Values below are stocked.
p/n: #41000 1000 gram (MTR-90 set-up)
p/n: #80005 5000 gram (Studer)
Precision spring scales
Download PDF

NEW Metric & SAE Wrench Sets

Available Online
Quantity of 9, well made, 12 point, forged and chromed pieces. Fully polished.

Molded plastic carrier. Well made in India.

Metric Set - p/n: TLS.WS.MET.9
SAE Set - p/n: TLS.WS.SAE.9
Open end wrench set

Magnetic parts picker w/ LED light

Available Online
The LED light, an extension length of 32 inches and a strong rare earth magnet makes this by far the best we've ever found. Comfort grip, will pick up and hold nearly 8 lbs while actually enabling you to see what you're trying to pick up!
A must for every tape recorder tech's toolbox.
Magnetic picker

Extendable Inspection Mirror

Available Online
Need to see around corners and under the chassis? This item does it and the back end has a small rare earth magnet enabling you to pick-up that tiny screw you lost. Extends to 19 inches.
Another must for every tech's toolbox.
Inspection mirror

Head, Red & Roll™ Cleaner (HR&R)

The amazing cleaner for everything in your tape path.
Available Online
"The Right Stuff". Advanced chemistry for the audio professional, HR&R is a highly effective audio/video and all around shop cleaner. A proprietary blend of ozone safe, azeotropic hydroflurocarbons (HFC's), HR&R super cleans and degreases safely without the risk of rust or corrosion. An industrial duty product which is non-toxic and non-flammable. The preferred head cleaner of The United States Library of Congress, American Folklife Center.

Head, Red & Roll Cleaner is available now.
To order: "Click here"

Ships non-hazardous & D.O.T. unregulated.

Tape path cleaner

MRL - Reference Alignment Tapes

always a 10% discount at our online store
Available Online
We've kept it simple. We recommend and sell only what we consider the most useful and cost effective versions of the MRL tapes - the one's we use in our own shop - and we sell them at a discount.

For most applications, we recommend the two-speed, 11 minute tapes.
Available in: 1/4", 1/2", 1" and 2"
Recommended test tones: 1khz, 100hz, 4khz, 10khz and 16khz
Record levels: 250nWb/m (+3) and 355nWb/m (+5.5)

Stop guessing and get yourself a new alignment tape!

MRL alignment tapes

Bearings and lubricating oils for Recorders

Bearings, lubricating oil and mechanical components

Available Online
In stock , a low-noise, precision bearing for virtualy every tape recorder application. No matter how obscure...Far too many to list here.

Got a bearing part number or a specific machine application ? "Click" the envelope and send us a preformatted email inquiry. We'll get back to you shortly.

Oil and lubrication requirements are very specific. Using the wrong oil in your application can be disastrous. Always use the manufacturer's recommended lube or check with someone who understands the compatibility issues before making a substitution.

We've got the right lube for all your Otari & Studer plain bearing motors.

You can buy bearings & lubrication at "Shop PrecisionMotorWorks"
Ball bearing selection
Otari lubricating oil
Studer lubricating oil

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