Tag Archives: txsound

An unhealthy obsession

with fake Sennheiser MKH416 microphones

UPDATE: 7/18/2017: REFUND RECEIVED!!!  In recent weeks, at least 2 more sellers of fake 416’s have popped up on ebay, all from China. That makes at least 4 ebay sellers to date.  

Fake MKH416 refund received! Thanks,  Lam Tin Hung!

Fake MKH416 refund received! Thanks, Lam Tin Hung!

UPDATE: 7/10/2017 An Ebay return claim was filed based on counterfeit goods, and the fake 416 is on its way back to China. They fronted the return cost of shipping (US$54), and say they will refund the purchase price upon receipt of the mic. They have been very cordial in the transaction. 

Last month I knowingly purchased a fake MKH416 so I could compare it with a real MKH416. It just arrived today, with case, in a padded envelope.

OK, we’ll get right to the good stuff first. If you are here looking for an competently made, uncompressed audio comparison between a real 416 and a fake 416, its just below.

Listen/Download the Real vs Fake MKH416 Comparison Audio File Here

After listening to the file, and maybe reading the below saga, bookmark this page, as I will be documenting my efforts in refunding the $490 spent on this mic from ebay. In the process, I’m developing somewhat of a relationship with the seller, and hope to get an interview.

The file is a 24bit, 48k stereo wav file, with the fake mic on one channel, and the real on the other. See if you can determine which is which. The file is 45MB, about 2:00 minutes. Recorded interior and exterior at different distances, on and off-axis. Use your favorite playback utility that allows you to solo A/B either channel into both ears. Or split the stereo track into two mono files and solo them. Can you identify the real 416? Left or Right?

The two mics were recorded using a Sound Devices Mix-Pre D into Audacity running on a Macbook Air. The mics were plugged straight into the side of the Mix-Pre D, setting them about an inch apart.

Which mic is which? Is the fake Mic 1 on the Left, or Mic 2 on the right? Any mixers out there confident enough to take a chance on being wrong? Leave a comment.

Background

Fake MKH416’s have been in the marketplace for at least 3 years. They were/are sold primarily through ebay. Prices were initially very low, about US$300. When users discovered that the market was tainted by fake 416s, the sellers responded by raising the price of the mics on ebay, to make them seem more like their genuine counterparts. Sennheiser eventually took action and managed to respond with various cloak and dagger stuff on which they don’t wish to expound. They expanded their website to respond to counterfeit inquires, and added holographic labels to the boxes, stuff like that. At least with the 416, their efforts seem to  cut down much of the distribution of fakes.

Real 416 (L) and fake (R). Notice paint underspray inside XLR, and silver vs gold pins.

Real 416 (L) and fake (R). Notice paint underspray inside XLR, and silver vs gold pins.

However, there are sellers on ebay peddling fake 416’s. Who knows if there are hundreds stored in some Shenzhen warehouse?

I have a sideline business that upgrades the older 416 T-power mics to 48 volt phantom at www.416Tupgrade.com. Resultingly,  I’ve been particularly interested in the daily street value of the 416 microphone, as I have ended up with a pile of them from R&D efforts. I’m interested in how the sale of counterfeits  and other marketplace factors effects the mic’s value. So I’ve been following the sellers of fake 416s on ebay for a couple of years. And my fascination with the affair led to me buying my own counterfeit 416, just to get my hands on one, and test it, compare it, and follow the seller’s trail through an ebay purchase. Down the rabbit hole I go!

A quick review of everything we know about spotting a fake Sennheiser MKH416:

They are typically sold on ebay from sellers in China. The box is the old-style blue striped Sennheiser Box. The plastic case often has the blue “Sennheiser” painted poorly. The label on the box may have the “U3” inverted to “3U”  The foam windscreen is squarely cut and looks cheap. See photos below.

Fake 416 Windscreen

Fake 416 Windscreen with its chopped off head…

DSCN1624

Many have said this case paint job is sloppy. This one looks pretty good.

Rusted staples on the manual, WTF?

Rusted staples on the manual, WTF?

Shipping manifest from "Bill"

Shipping manifest from “Bill” over in Hong Kong

These titled photos are being sent to eBay along with the return authorization

These titled photos are being sent to eBay along with the return authorization

I've been alerting eBay about these auctions for months. This time, I'm the buyer!

As an observer, I’ve been alerting eBay about these auctions for months. This time, I’m the buyer!

Spelling errors in the manual

Spelling errors in the manual

More spelling errors

More spelling errors

Fake box label. The early fakes had the U3 inverted. They've since fixed that.

Fake box label

Fake 416's come in this colored box. -Pretty dog eared. The inventory's probably been moved around quite a bit

Fake 416’s come in this colored box. -Pretty dog eared. The inventory’s probably been moved around quite a bit

Here’s some internal construction photos of a fake 416 (top) and a real 416(below)

Fake top, real bottom.  The interior probably came off their production line for vape pens.

Fake top, real bottom. The inside assembly look straight from a mass production line for electric vape cigarettes.

Teardown, Fake top, real bottom. Fake is an electret condenser design.

Teardown, Fake top, real bottom. Fake is an electret condenser design.

The fakes have none of the RF suppression properties of the real thing. They will noise-up around plug-on transmitters and walkie-talkies.  The output is about 3db lower than the genuine. (compensated for in the above sound file.) The painted lettering on the mic’s side is uneven and the letters are taller than the originals. The “Made in Germany” insignia is roughly stamped,  unlike the authentic mic.

Oh, and they sound very similar, if not almost just like the real thing. Did I mention that its very difficult to to tell the two apart by ear? Well, it is.  Anyone purchasing one of these fakes who didn’t know any better (like a student, amateur docmentartian or a wedding photographer) would be very happy with it.

The fake sounds miles better than the noisy 416 wannabe Aputure DIety. Those guys could learn a thing or two from our counterfeit friends. Much simpler design, too. See Rastop’s cool teardown video of a fake below. (He’s Gotham Sound’s repair technician). We immediately see that the build quality of the circuit board is pretty nasty.  The FET and 1 gigohm resistor indicate a passive electret capsule is mounted above the circuit board.

I see no need to replicate Rastop’s efforts. I’ll soon be making my ebay refund request, and I want to keep the sellers from making a damage claim. And if ebay’s policies follow through, or the seller responds negatively,  I may be able to keep the mic anyway, like a war trophy.

Some details on the counterfeiters:

The ebay auctions will always describe the 416 as “99% new”, or even “90% new”, as they feel this exempts them from having to respond to counterfeit claims.

The current (June 2017) ebay seller’s ID is vpower.hk8 or emma2012g.

They also have an alternate ID of w3vpower.hk 

The seller seems to be a Chinese company that makes parts/batteries for electric bicycles. 

They sell bicycle parts, kitchen utensils, hello kitty ice cube trays, camera filters and fake Sennhieser mics on their ebay seller pages.
 
The company’s web address is http://www.vpower.hk
 
They provide phone, email, and physical address info on their site. Email: contact_us@vpower.hk
Phone: +852 98199088
Address:
1st Floor, 12 Unit, A Building
Yupi Industry
Dongcheng Street,
Yongkang City
Zhe Jiang,China
The individual who handles the paypal account calls himself Tin Hung Lam and gives an email address of in31amp@outlook.com
The fake microphones are currently shipped from (probably a showroom)
HOCO Technology Limited
Room A 10/F Tower A Billion Centre
1 Wang Kwong Road
Kowloon Bay , Kowloon Hong Kong
Tel 00852-36102558
Email borofonebilll@hotmail.com
HOCO Technology is a firm in Shenzhen who makes a wide variety of products and mobile phone parts. More info about them at their homepage and at this supplier aggregator site. 
authored by Pete Verrando

Zoom F8 backup bag rig

I’m pairing up the Zoom F8 recorder with my size-modified Lectrosonics Venue Field receiver. See txsound’s Venue mod for details on how I trimmed about 1″ of thickness off that box for potential bag use.

The actual bag is a Canon 1EG camera gadget bag, about $64. (Don’t hate on me, K-Tek)

I created a little “front box” for easy access to transmitters and other stuff.  Before it gets used for anything serious, I want to run it through its paces as a backup to my Fusion rig. There’s always a lot to learn about the peculiarities of a new recorder.\

F8 bag rig and Deva Fusion rig

 

txsound zoom f8 venue bag

Seeburg 1000 “Window Unit” Background Music Player restoration

A recently edited presentation of our Seeburg 1000 BMC player. We call it the “Window Unit”

Seeburg 1000 players employ special 9″ records with 2.5″ center holes. The device plays both sides of each record, then lifts the stack to the top of the spindle for replay. Seeburg BMS (background music systems) were In widespread use in department stores, restaurants, and other retail and industrial locations from the early 60’s through the late 70’s. They have become very popular mid-century modern artifacts.   The thousands of  music selections were individually crafted by professional musicians and studios, and are utterly representative of  a unique and often forgotten part of American culture.   The 16 rpm records are widely available on ebay.

This is my 4th complete restoration of a Seeburg 1000 player.  Thanks for watching!

-Pete Verrando

A saga of Kentli Lithium-Ion 1.5 volt AA rechargeable cells.

Many folks are very excited to see the first rechargeable Li-Ion AA battery, made by Kentli. 

KENTLI-8pcs-1-5V-2800mWh-font-b-AA-b-font-rechargeable-Li-font-b-polymer-b

Kentli AA Lithium-ion rechargeable cells and charger.

 

 Here’s a cut-away view of their exciting new AA cell:

so_8

The guts of a Kentli Cell.

The Kentli AA Lithium-Ion cell was perceived as an exciting development, because all Lithium Ion cells are normally 3.7 volts. So even if the cell could fit into the AA form, the voltage was too high for 1.5 volt applications.  What Kentli did was cram a 3.7 volt Lipo cell into an AA enclosure, and also stick a 3.7volt-to-1.5volt regulator inside there as well.  The charging groove (see diagram) allowed the cell to be charged directly by the charger at 3.7 volts, bypassing the “motherboard” (regulator).

Why would we want a Li-on AA cell, anyway?  The perceived advantages:

1. Ni-mH cells, the current rechargeable of choice, provide only 1.2 volts per cell.  That missing 3/10ths of a volt can really add up when using multiple cells in series (battery)! The lower voltage also increases current draw, shortening the power-up time of the cell.

2. Lithium Ion cells maintain almost their rated voltage right up till they die  Other cells, the voltage slowly drops as the cell discharges.  Many digital devices will shut-off when the supply voltage falls to a certain level, leaving much potentially live-giving energy in the cell.

3. For their weight, Lithium-Ion cells currently provide the most deliverable power than any other type of cell. They charge fast, are very reliable, and last for many charge cycles. They are also tolerant to recharging at various states of discharge.

More Advantages:

4. Rechargeable batteries create less land-fill waste.

5. Rechargeable batteries create incomeas you can bill the client for these batteries like disposables.  So, they can routinely add about $20 or more to your daily rental income, without buying disposable batteries.  Over a year, that can add up (conservatively) to about US$3000. (that’s if you work only about 14 days a month as a professional location sound mixer)

So how well do Kentli Li-ion AA cells work?

As Chinese Industry is prone to do, Kentli did some slight-of-hand marketing with these products. They listed the capacity in milli-watt-hours, so they could print that big 2800 mWh on the side of the cell.  For people who don’t pay attention, this rating gives the mistaken impression that they are more powerful than 2700 mAh (milli-amp-hour) Ni-MH rechargeables. 2700 is a common value when looking for a high quality Ni-MH rechargeable.  At 1.5 volts, 2800 mWh translates to about 1867 mAh,  so the Kentli cell technically has less power. But Kentli claims their cell lasts as long as the Ni-MH, because the regulator allows the 1.5 volts to be maintained till the cell is completely exhausted.

The street price for these Kentli AA cells is about US$11 per cell, and the charger about US$20. More expensive than Ni-MH rechargeable. They are shipped directly from China through a few distributors, including sellers on ebay.

 

lectrosonics smv verrando txsound

A Lectronics SMV transmitter. 1/3rd of the package is for the cell.

We bought 12 AA cells and 2 chargers to give these units a workout in our Lectrosonics SMV transmitters.  The SMV uses only one AA cell.  A disposable Energizer Lithium AA will power it for 5 hours (the longest). The best NiMH rechargeable will power it for about 3.5 hours.

And the result? A fresh Kentli AA, right out of the box ,will power the SMV for 3.5 hours. Same as a high quality, 2700 mAh Ni-MH rechargeable.

But here’s the rub, in a few easy steps.

1. In my application, Kentli AA’s take their internal cell from a full charge to near-exhaustion in every cycle. Over the long term, I think Li-Po rechargeables prefer a lighter charge-discharge cycle. so with this workout, these Kentli cells won’t last for very many cycles. A Lectro SMQV would treat the cells more gently, distributing the current draw between two cells, and possibly resulting in better performance.

2. Kentli AA’s use a 3.7v Li-Po cell and convert it to 1.5 volts. There is inherent inefficiency in this conversion process.  The Lectro SMV then takes the 1.5 volts and inverts it up to 5 volts, and 3.3 volts, to serve the various internal functions. Every time you convert a voltage, you lose some efficiency and power, in the form of heat.  The Kentli is already stretching the capacity to the max of its tiny 3.7 volt, 760 mAh cell, every time it is charged and used. With the SMV, there are multiple conversions, and those power losses add up.

3. These days,  the “power down” mode of many devices is not a true power-down. Even after its turned-off, the SMV draws a tiny “quiescent current.” This is simply power to enable the SMV to power back up with a momentary button-push. The Kentli sees this quiescent current, and therefore keeps its motherboard alive, affecting a continuous drain on its cell. So leave a freshly charged Kentli in the SMV overnight, and it will be dead in the morning.

4. Maintaining AA rechargeables for location sound use is a pain in the ass. They get lost easily. I lost one in the snow on the very first shoot! They are difficult to keep separate between used and unused. They require chargers to be travelled and plugged-in. They require extra time to sort and charge and check at call and wrap.  They create a level of uncertainty in the production process. Will this be the shot when the battery dies for good?

5. And obviously, in the SMV, a rechargeable will run for only 3 hours, and a AA li-ion disposable will burn for 5 hours.  In most cases, 5 hours is enough time to get us to lunch, when the battery can be replaced.  The SMV is designed to accept a cell that swings from 1.9 volts to .9 volts, and before it dies, will suck every last ounce of power from the cell!

6. Don’t talk to me about the Lectro SMQV, the double AA version. I know they will run twice as long. I don’t care. I like the smally-small SMV for so many reasons. I use it as a drop-weight when running the lav cable down shirts and blouses and pant-legs. The SMQV is almost as large as a UM400A, Lectros classic 9-volt transmitter, of which I already have a shit-ton.  The SMV is great for use on children, with their tiny pockets and elastic waistbands. It also has the lowest profile in a pocket or bra-strap.

Oh, and the Kentli Chargers tend to die. 

kentli charger txsound

The Kentli Charger with its ring-groove contacts. They contact directly with the Li-Po battery and charge at 4.2 volts.

kentli, location sound mixer, txsound.com

The innards of the Kentli AA charger

P1010256

A 5 volt phone charger inserted into the 5 volt rails of the Kentli charger. Fixed!

Of the two Kentli chargers I originally ordered, one died a couple of months in. The dealer asked for photographic proof that the charger was dead. They sent a replacement from China, which never arrived, and then sent me another.  Eventually I received both chargers, so now I had four. Then the other 2 chargers immediately died.  Taking this opportunity to either throw away the dead chargers, or take them apart, what do you think I did? The charger consists of a very flimsy switching power supply converting your AC house current to 5 volts DC. The voltage is then applied to a smart charging circuit for the AA cells. The flimsy switch-mode supply was the obvious culprit, so it was replaced with an outboard 5 volt phone charger, of much more robust design. So now we have 4 chargers.

 

Then, the Kentli AA’s start to show signs of age.

This is about the time that the Kentli AA cells stopped delivering 3 hours of power to the SMV’s.  This is not the cell you want in a transmitter that goes out on a competition shoot, where you don’t have access to the talent once the action begins. I would guess I got about 100 charges on my Kentli’s before they began to show signs of expiration. The chargers show a full charge even on the cells that have stopped performing. In a less-demanding environment, (like an LED flashlight or an ipod dock) they may give better service.

And Alas! one Kentli drops to the floor and pops open like a Zippo Lighter! (Also the shrink wrap on the cell will begin to tear and peel with daily use. )

kentli AA txsound.com

Pops open like a Chap-Stick!

kentli txsound sound mixer verrando

The Kentli regulator board.

UPDATE : Curious about the quiescent current draw of the Kentli Cell, on its own, we hooked up a micro-amp meter between the regulator board and the Li-Po cell. The result:

kentli AA self discharge txsound

Kentli AA cells discharge on thier own, with a constant current draw of 29 microamps from the internal “motherboard.”

You guessed it. The Kentli motherboard is drawing 29 microamps from the cell at all times.  By comparison, Lectro transmitters, when powered down, draw about 5 microamps from the cell.  This is in conflict with the advertising claim made on the Kentli promotional material:

discharge claim kentli txsound.com

Advertising claim from Kentli’s promotional materials

 P1010251And whats this? A 3.7 volt, 2.66 wH li-po cell! That’s 2660mWh, or 718 mAh! Not 760 mAh, as the label claims!

So there’s no doubt the Kentli folks are really pushing the envelope with this initial attempt at a 1.5V Lithium-Ion rechargeable. A little more conservative design paramaters are required for location sound use. But for flashlights and home use, I’m sure theres no telling! And no telling of what’s to become of my little AA canisters for a location sound mixer on the road!

16" transcription record

Presto T-68 16″ Transcription Turntable Restoration

 About 3 years ago, I saved the pieces of this 16″ transcription player & cabinet from a dusty internment.

The 16" platter, stripped, cleaned and ready for re-felting

The 16″ platter, stripped, cleaned and ready for re-felting

presto turntable

cabinet as found

16" presto turntable

Project in pieces before restoration

Presto top plate with idlers removed.

Presto top plate with idlers removed.

 

 

 

busy day at txsound

busy day at txsound

 

 

(Click the thumbnails above for a larger “before” view). ,  This Presto T-68 Transcription Turntable with Pickering 190D Tonearms was used at an Air Force base in Fort Worth. Found inside the cabinet was a 16″ acetate record, with the lacquer falling off the aluminum substrate. The disc labels indicated the acetate had various Reveille bugle calls, marching and teletype sound effects. The military base had its own radio station, or perhaps they used these effects over the public address system for PT!

acetate presto turntable txsound verrando

The acetate found in the cabinet.

acetate labels presto turntable

Old Acetate disc labels from in bottom of turntable cabinet

 

 

 

 

 

 

 

 

 

Upon complete disassembly, work started on the motor & start capacitor, with a gentle variac power-up to check for shorts in the windings, or a bad capacitor.  It’s an an Ashland Hysteresis Synchronous motor of 1/100 horsepower. after a complete overhaul, the motor ran continuously for a couple of days to observe operating temperature, let the bearings settle in,  and discover any latent noise or vibration issues.  New motor mounts were installed as well.

Ashland motor presto turntable

Motor removed for teardown, old lubricant removal, reassemble and re-lubricate. Slow power up with variac.

Three rubber idler wheels transfer the motor’s energy to the platter at 78, 45 or 33 1/3rpm, depending on which plane of the spinning motor shaft is engaged (see photo below).

presto t-68 idler wheels turntable txsound

Transport with Terry’s new idler wheels installed.

The existing idler wheels (above) were hardened and crumbling. The brass hubs were re-surfaced by Terry’s Rubber Rollers. The motor and idlers get the platter up to speed in about 1/4 of a platter rotation. Pretty quick, which was important for the operators ability to tightly cue the audio tracks.  

The tonearms are type Pickering 190D, originally wired for mono.  BTW, Mr. Pickering holds the original patent on the moving magnetic phono cartridge!  These tonearms were heralded for extremely low vertical to lateral moments of intertia, and minimal vertical mass.  Because of the big swing of a long tonearm, the tracking error is less than 2.5 degrees.

pickering 190D tone arm

Pickering 190D tonearms, mono wiring & magnetic arm rest.

pickering 190 txsound verrando

The Pickering 190D (click/enlarge)

The tonearm’s extremely low head-mass  can deftly handle a warped record very nicely.  The rear tonearm is intended for a 78 rpm cartridge/stylus.  The front arm is for a microgroove cartridge.  A top- mounted rotary switch selects which arm is fed to the pre-amp.  Before restoration, the signal passed through a Pickering model 132E passive equalizer before being pre-amplified by a mono model 230H Pickering tube preamp.

 

 

pickering 230H preamp. txsound

Ad for the original preamp. (click/enlarge)

pickering presto

Pickering passive cartridge equalizer.

presto tonearm selector

78- LP tonearm selector

presto power switch

Power switch with a hand-made plastic mount-plate

 

 

 

 

 

 

 

 

 

Both  tonearms get re-wired for stereo, no small task with hair-thin oxygenated tonearm wire. The rotary switch was replaced to enable stereo switching between tonearms. The mono Pickering equalizer was removed(which will fetch about $100 on ebay) and the resulting empty hole with a bat-handle power switch for the motor, a more practical use of the space.   The turntable previously was powered-up when the speed selector was enabled. A  black switch mounting plate was created to match the other label plates on the plinth.

 

 

A new stereo tube preamplifer is now required inside the cabinet, so a Little Bear Stereo Valve Preamp was shipped in from Hong Kong.  (below)

 

Little Bear Presto Pickering

The popular Little Bear stereo tube pre-amp from Hong Kong.  Very nicely designed!

 

presto rca patchbay txsound

RCA patchbay on rear panel.

 

To allow the user to select the internal or an external preamp, An RCA patch bay  is added on the rear cabinet panel. Also shown is the ground lift switch, power connector and chassis ground terminal.

 

 

 

 

 

 

 

pickering presto turntable txsound

Assembly and wiring of tonearms. Individual Channel signal/ground wires eventually made into twisted pairs for hum suppression.

 

The cabinet was a challenge, especially the plinth. The 3/4″ plywood base surface was covered in a thick, ancient, funky, dull- green laminate. The surrounding metal was painted industrial grey with a good deal of chipping & corrosion. The metal surrounding the laminate was refinished in hammer-tone grey .  The funky-green clashed with the other colors, so the wood top was refinished in solid satin black.  The platter had plenty-enough green in it after the re-felting, which is done with felt, spray adhesive, and careful lathe-style trimming with a razor. The plinth’s vertical edges were stripped down to the bare metal and polished to a bright shine, almost chrome. The polishing process was observed in a motorcycle restoration shop, and has been sucessfully used here on lots of projects.  (Enlargable thumbnails below)

2014-07-03_13-08-52_159

2014-07-04_13-36-10_96 2014-07-04_13-36-41_12 2014-07-04_13-41-56_855 2014-07-03_12-46-10_159 2014-07-17_21-07-16_881

 

 

 

 

 

 

 

cabinet7 cabinet8 cabinet9

 

 

 

 

 

presto24bh

Collection of 16″ transcription records are stored inside the cabinet. Those suckers are heavy.

 

The Presto- DuKane cabinet, preamp and associated wiring came together as pictured. The tonearms get fitted  with  Shure M91ED cartridges, the rear cartridge with a 78rpm stylus. The unit is extremely well grounded, including the motor shell, and cabinet ground is independent of signal ground. Wether using the internal or an external preamp, there are no hum issues. As a precaution, a ground lift switch was added to the rear panel.  Power lines are capacitor bypassed at the entry points and at the power switch.  (below pics are enlargeable)
P1030664h presto4h presto17H presto19h presto20h

 

 

 

 

 

 

 

The table adds a special allure to vinyl activities. A heretofore ignored  pile of 78 rpm records have provided some very interesting listening!  It’s the record industry in its infancy. Various recording techniques can be discerned, qualities, different equipment eras, groove depth variances, etc can all be heard.

 

 

 

 

presto turntable t-68 transcription verrando txsound

 

There’s a million cheap 78s, lps and 45s still floating around out there, in thrift stores, estate sales, and flea markets.  Many found 78s  have never been played, and those make for remarkable listening. Back in the day, the commonly used steel needles would destroy a 78 after 20 plays. Many outstanding shellac records are still out there, They are remarkable examples of recording skills and standards through the era.

 

presto transcription vinyl txsound pickering tonearm trans.com txsound

The 60’s produced some remarkably well mastered LP’s as well.  I particularly like the Command 35mm series, which are still in plentiful supply at the above mentioned sources. See you at the Goodwill!

MORE ABOUT TRANSCRIPTION TURNTABLES….

In the US, professional transcription turntables were primarily made by RCA, Gates, Fairchild, Presto, and McCurdy in Canada. They also required a separately purchased  “transcription” tonearm, about 3″ longer than a standard tonearm. The extra “swing room” these arms create also reduce stylus tracking error, especially on 7″-12″ records.

I’d been searching for a 16″ transcription turntable for many years. These tables are a unique and dissappearing part of broadcasting history.  Unlike a 12″ platter, they can  accommodate vintage 16″ transcription vinyl records, popular in the radio industry through the 50’s, 60’s, and 70’s. Amazingly, for their size, these records only contain about 15 minutes of program material per side!  That’s because the grooves are spaced far apart. The discs typically cannot fit on a standard 12″ turntable platter without hitting the tonearm base. The US Armed Forces and Veterans Administration used these records extensively to distribute their radio programs. The records also were popular for distributing library music, jingles and commercials.
70-D_001

RCA 70 transcription turntable. Thousands of these used to reside US radio and TV stations.

Beardsley.press

A 16 inch record press

 

Gates transcription turntable txsound

Earliest version of the Gates CB-500 Transcription turntable.

The big turntables often came mounted on a cabinet, the size of a dishwasher. The earliest tables used this space for a complex, gear driven, flywheel-stabilized motor, These motors provided the necessary torque required for slip-cueing records and fast startup rotation.  Eventually, the torque came from smaller, hysteresis sync motors with idler/puck drives.  By the early 60’s these became the standard turntable design for radio/tv stations. In the early 80’s, Technics Corp. introduced powerful, direct drive, crystal controlled motors. They were adopted quickly by radio stations and used until CD’s replaced vinyl entirely…

rcaTTunderside
Huge flywheel motor affair that is under the platter of the early RCA transcription turntables.
Maybe there's still some hiding out there, somewhere?

Maybe there’s still some of these hiding out there, somewhere?

RCA BQ-2B 04

A more recent underside of a transcription turntable, the RCA BQ-2B. I do not recommend placing a tube amp in the cabinet!

 

 

 

 

If you’ve got room in your listening area for one of these behemoths, you’ll find them few and far between, and priced outrageously. And that’s before the freight shipping required to send to your place.  The most current and popular transcription unit is the Gates CB-500 ,  and the cabinet (if you can find it).

The Gates CB-500 and cabinet. The Holy Grail? This one's in Russia! The front panel controls are a sloppy, abortive add-on. 

The Gates CB-500 and cabinet. The Holy Grail? The front panel controls are a sloppy, abortive add-on.

 

 

 

gray-research-model-206-12-1 tx sound verrando

Grey Research Viscous Damped Tonearm with installation template.

 

 

 

 

 

 

 Personal Story Time: In my college days of Radio and Television (circa 1980), the school had a large, 3 camera TV Studio, with a huge cyclorama curtain surrounding the walls.  One day, while scrounging behind the curtain, I found two of the huge RCA transcription turntables, in their massive cabinets. They had the coveted Grey Research Damped Transcription Tonearms, so named, as the arm rode on a layer of oil to isolate it from the turntable’s vibrations. And also to minimize lateral friction. The RCA tables were in deplorable, but restorable condition. Piles of 16″ records cluttered the space around the machines. I had little interest in vintage gear in those days, and forgot about them.  20 years later, I  learned l that when the TV studio was renovated into a dance studio, the turntables had been unceremoniously trashed.  Truthfully, over 30 years later, I still have lucid dreams about finding vintage broadcast equipment in the bunkers and catwalks of my alma-mater’s fine arts building.  – by Pete VerrandoMeadows_School_of_the_Arts