TR 12 H Rek-O-Kut (ROK) Broadcast Transcription Table

[adnick]

Just picked up what was advertised as a T12 but found T43H on the ams when I unpacked it. Based on design and the fact that it’s a factory 33 &45 it must be a later edition.

Started the process of cleaning it up, really not in bad shape.

Once it’s cleaned and working, I’ll strip it for a new paint job, right now it’s between, candy red, emerald green, candy gold....

Concurrently building a new plinth, just made one for my Rondine Deluxe, so it’s fresh in my mind.

 

[adnick]

Test runs were not bad:

1st without mat 33.5 w/f 1.30
2nd (soaked idlers overnight in hot soapy water) put original mat in place 33.34 w/f .34

w/f can be reduced even more with some sound dampening and a good leather mat.

Did some sanding, getting ready for paint...

 

[adnick]

Some parts on this table are labeled T12 others are T43, it is an H version. I’m assuming a later model because it’s labeled 45 & 33 and has corresponding idlers.

Idlers are sized based on rpm and are actually 2 idlers combined per side.

They are 1 inch tall and made of solid rubber, and the bearing shaft is 7/16” and hollow with oil wicks inside.

The platter shaft is 3/4”.

The diameter of each idler determines speed of the platter.

One each side, one wheel contacts the motor pulley and the other drives the platter rim.

There is no stepped pulley on the motor and nothing moves up/down.

All one has to do to play 78 rpm records is change out one of the idlers, nice design.

The 45 rpm idler is in fantastic condition, the 33 rpm is ok but has one small divot on the pulley wheel.

These idlers are considerably different than my Rondine idler, so they’ll require custom manufacturing.

It’s quite enough to us with the original idler but I’m pursuing a set of custom idlers.

Looking for someone with a 78 rpm idler, would like the diameter of each idler so it can play 78s also.

If anyone reading this has a 78 rpm for a T12 or 43, I’d appreciate the measurements (-:

 

[adnick]

Plinth is coming along.....going to incorporate a support for the platter shaft housing, not as involved as one I’ve seen here on AK, but it will provide extra support. Will add some photos of what iv come up with....

Have 2 tonearms for it:

First one is a Grado Micro Control and has been refreshed with Litz Cardas wire...

Next one is a Pickering 190D which needs a paint job.

 

[adnick]

Made some progress, paint is close to finished, have one more small piece to do , and need use some glaze on the rest.

Made my own platter shaft support, not as fancy as others I’ve seen but it works....

Also started the installation of my Grado tonearm, have the original instructions, mounting distance is 7&7/8 inches from center, but that seems too close?

The process continues

 

[adnick]

Did some research and now can give credit to the guys that gave me the bearing/platter shaft support concept.

@bob06 & @mfrench in thread https://www.audiokarma.org/forums/i...making-a-plinth-for-my-rok-l-34.635857/page-4

There solutions are much nicer than mine.....

Should also point out that the bearing/shaft housing goes through 4 layers of 3/4 inch Birch Plywood,, so it requires some careful planning/cutting to line things up....

VR

Andy

 

[adnick]

Decided not to paint the idler cover, did a quick polish, doesn’t look bad but need more work....

Installed the power outlet, not simple with 1” thick wood, took a while (-;



have to decide how I’m going to connect to the Grado tonearm, not sure if I’ll keep the Din connection, may add RCA terminals?

It’s alive!

Adjusted the speed, got it to 33.31....the motor is dead quite, no increase in ambient noise when it’s on but, I can hear the idler up close. Believe a new idler will solve this, it’s not bad have to be right next to it to hear so it will still get used until the new idler is done.

 

[adnick]

Working on the Pickering 190D, was in need of a paint job, got the arm done, not polished yet, but still need to do the base and rest....

Knew going in that 2 arms on here without making the plinth larger would have limited mount positions.

Believe the Pickering is going on the opposite side, as in the photo....have a GE chrome mono cart for it.

Only other viable mounting option is on the front, right behind the speed control, don’t much like that...







One thing of interest, this table’s orientation is different than most T12 & 43s many are oriented with the speed control in line with the front corner ( sorta at an angle). See the photo for an example.



This one has the speed control centered in the plate. I’ve searched the web and have not discovered any discussion on this, anyone have more information?


Other projects, for other people, are slowing me down (-; but I’m waiting on some custom made idlers anyways......

 

[adnick]

Finally figured out that the table is probably a TR12H, the recorder versions have the centered speed control.

First test spin today, some Frank Sinatra, Grado tonearm is outstanding with the Pickering XV15

The Pickering 190D will be my mono arm, has a GE RPX Pro, but will take me a bit to get it completely ready to use.

Also need to finish the plinth, still quite a bit to do underneath...

 

[truckrglenn]

Wish that I could do something like this.

 

[adnick]

Wish that I could do something like this.

While I believe “anyone” with some instruction/training can do these kind of things, there has to be the desire and commitment. That’s a bit of over simplification, but the point is still apropos.....

There was a lot of labor involved in the process I took, it could have been done with much less labor intensity.

The plinth could have been done by layers of plywood and new paint doesn’t add to function (-;

These old tables represents a near perfect example of form and function, especially in complexities.

Right now they are cheap, easy to rebuild, and most rumble (if there) can be eliminated with a new idler...would just make sure it has a Hysteresis motor that’s not effected by changing voltage, otherwise one needs some sort of voltage management system.

Just keep in mind, in most of these tasks, “failure is not fatal” although it might require more labor


VR
Andy

 

[adnick]

Had to re-wire the Pickering 190D it made much noise in its original configuration.

Sounds great after the re-wire, even with the el cheap o AT cartridge...

Have a Karmadon GRAY 108 clone, made of magnesium, coming so I’ll have to decide which arm will go where....

Filled the plinth with compressed jute, and added some adjustable feet, the inside of the plinth is sectioned off, left the motor area open for ventilation.

 

[adnick]

Picked up a Karmadon 16” Gray clone, very nicely done, made from magnesium, so it’s not as heavy as it appears.

Rewired with Litz wire and made an RCA junction box.

Not a good week for me but managed to get it installed.

Didn’t want to drill more holes in the deck, made a tonearm board to mount it on, however the Gray mounting hardware complicated the process...

Made the arm board adjustable, very easy to change overhang distance.

Speed adjustment is really simple and extremely precise with an app like RPM, the black is both the off/on switch and the speed adjustment, there are set screws for repeatability.



The height adjustment is based on the bolts protecting below the deck, without doing that one must get the bolts and arm board exact, otherwise the height adjustment will be incorrect.

Using a Shure M44e, very pleased with this arm.

Also made a removable arm board for the Grado arm, want to quickly change over to a Pickering 190 mono setup.

VR
Andy

 

[setup1]

Picked up a Karmadon 16” Gray clone, very nicely done, made from magnesium, so it’s not as heavy as it appears.
Andy

Congratulations on a fine choice!

The 16" Japanese clones are heavier than the original Gray 108, so Karmadon made a great choice using magnesium.

 

[adnick]

Congratulations on a fine choice!

The 16" Japanese clones are heavier than the original Gray 108, so Karmadon made a great choice using magnesium.

Thanks,

Very impressed with the arm, the damping is well worth the effort, needle oh so slowly engages the vinyl, and tracking is outstanding.

Started making a set of weights for the “headshell” to adjust VTF, then realized it was mounted far enough back that it allows access to the rear weight, not quick, but certainly not difficult.

Considering painting the top like Gray did to one model, believe the tuxedo black goes very well with a gray bottom....

This has quickly became my favorite table, just received the paint that was special ordered for it, House of Color, candy ruby red, just don’t want to stop using it now that both arms are functional ;-)

Have a few other things that are on my to do list, but these are incredible turntables.

VR
Andy

 

[adnick]

The selected Paint finally came, so it’s now candy ruby red.

Made a Black Walnut top to replace the outer support, also added tapered legs out of the same wood.

Dust cover is next, with a little more plinth work, and some mechanical upgrades.

The latest iteration:

 

[adnick]

The dust cover, my first attempt at one of these....did 45 all the edges, and used lexan.

Excuse the fact that it’s dirty, this is just a test fit, will post another photo of the finished product....

 

[adnick]

Received the custom made idlers from Abe Herbaugh, what an excellent job in design and craftsmanship.

Installed them and as expected, the 33 is so quite I can’t hear it, neither can my decibel app

The 45 has a slight sound so I’m going to explore that a bit, it’s not like the original, not nearly as loud, but it is detectable, most like the way I adjusted the arm....

Could not be more pleased with the results, very impressed with my refreshed ROKs, this one has exceeded my expectations.

 

[KentTeffeteller]

While I believe “anyone” with some instruction/training can do these kind of things, there has to be the desire and commitment. That’s a bit of over simplification, but the point is still apropos.....

There was a lot of labor involved in the process I took, it could have been done with much less labor intensity.

The plinth could have been done by layers of plywood and new paint doesn’t add to function (-;

These old tables represents a near perfect example of form and function, especially in complexities.

Right now they are cheap, easy to rebuild, and most rumble (if there) can be eliminated with a new idler...would just make sure it has a Hysteresis motor that’s not effected by changing voltage, otherwise one needs some sort of voltage management system.

Just keep in mind, in most of these tasks, “failure is not fatal” although it might require more labor


VR
Andy

It is beautiful, Andy. A note: The H models are truly broadcast grade when idler driven or the GH motor is used. The cheaper motors aren't quite broadcast, they're less expensive junior models often used at home and by those on a budget.

 

[adnick]

@KentTeffeteller really appreciate the comments, thanks.

Am familiar with your posts and obviously you have vast knowledge/experience with broadcast turntables, and as you can tell, I’m just a amateur hobbyist.

This all started with a Rondine B12 H Deluxe, thought it would be an interesting COVID project, never expected it would turn out to be such an outstanding table.

Had read multiple posts related to “unsolvable rumble” issues so it was destined to become a “shop” turntable, however after the clean up, new plinth and delrin o ring idler—wow! The thing was so quite, I even got out a microphone and db program to check for motor and/or idler noise, there was almost none, and the speed was dead on....

This experience peaked my interest in commercial grade transcription idler tables.

So I went looking for a “commercial grade” table, (broadcast grade is a more appropriate term, just showing my ignorance). Didn’t care who the maker was but new I wanted a hysteresis motor, with both 33 & 45 capabilities.

Came across several different ones but then saw what turned out to be the TR 12 H, at least that’s what my research indicated.

Had already been introduced to Abe, the maker of the delrin o ring idlers, so I asked him if he’d be interested in making some custom idlers for this beast, when he said yes, I purchased the table.

Was so impressed with the Deluxe, that it replaced my Denon DP 75 as my main sorta “presentation table” and the TR 12 H has now replaced the Deluxe.

My Regards,

Andy
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