[Scott B]

Have you ever wondered if it were possible to replace the stock 9" arm with a 10.5" LTD tonearm on your simplex? I did, but there was an obvious problem of the pre drilled cup hole being designed to take the current 9 inch arm.

My original idea was to just replace the cup with a threaded one to make adjusting the silicone fluid height much more fine-tuned and easy. I always found that the slightest adjustment to the cup can make a big difference in sound quality, and it's difficult to get right by having to loosen the bolt and adjusting by hand in the original design. 

Since I have a 3d printer I decided to design a threaded version of the cup, which I was able to do.  Before testing it out though, that got me thinking of whether or not it was possible to reverse engineer the LTD using all 3d printed parts to take advantage of the longer tonearm. I originally found this post:

http://calypso-tonearm.blogspot.com/2018/06/calypso-silicone-oil-tonearm-daniels.html?m=1

which was the original inspiration along with scouring through many other threads and taking my own measurements until I had enough information to get all the parts and relevant details together needed to complete the project. The key was to design a cylinder that would fit in the pre drilled cup hole and a "bridge" that would extend the cup far back enough to accommodate the 10.5" arm that went into. It turns out that the only non 3d printed parts needed were:

silicon fluid
fishing line
fine sand
tonearm wire (I used KAB SuperFlex)
cartridge clips (I used 1877 phono clips)
5 pin xlr connector
aluminum arrow shaft for the arm tube

I'm aware that others have successfully built well tempered clones, and I'm certainly not the first, but no other tools other than a hand drill, some sandpaper, and tap were needed to complete this. The counterweight was even 3d printed and filled with tungsten shot to get the right weight, but since the arm tube is the same diameter as the original arm, the original stock counterweights can be used.

So how does it sound?… While I can't say how it sounds in comparison to the LTD, which I've never heard, but it clearly sounds better than the original 9" arm that came with the simplex, by quite a bit to my ears.  The thing that stood out most to me was how much better the bass was in particular, but everything seemed more revealing and full bodied overall.

The goal here was just my curiosity to see if I could do it, but I'm so impressed with how it sounds that I won't be putting the old arm back in.


-Scott

[Rocket]

Hi,

Thanks for your write up. I found it very interesting .

Cheers Rod

[Scott B]

Thanks Rod!  Here are a few more pictures

[Rocket]

Hello Scott,

I am a total fool when it comes to turntables. I have a newish technics sl1200g turntable which I like because it is basically set and forget. I use a local turntable expert https://liquidaudio.com.au/ who sets up my turntables and services them for me.

You have far beyond capabilities of what I can do with turntables.

Thanks for your posting your adventure as I found it really interesting.

Cheers Rod

[VinceT]

Great work, you could be onto something here.

I know parts can be a bit of a wait with WTL sometimes. And the cup adjustment with the  wrenches is very clunky and difficult to make small incremental changes. That tweak alone is very useful, not to mention the tone arm.

[jjss49]

great job!!!

[Scott B]

Great work, you could be onto something here.

I know parts can be a bit of a wait with WTL sometimes. And the cup adjustment with the  wrenches is very clunky and difficult to make small incremental changes. That tweak alone is very useful, not to mention the tone arm.

Hey Vince, Thanks for the reply! The ability to make slight adjustments quickly with the threaded cup really is a game changer for getting the fluid height locked in.

Scott

[ketchup]

Very cool.  Bruce Thigpen 3d prints counterweight beams for his ET2 tonearms.

I have been printing some audio components here and there.  What filament did you use?

[Scott B]

Very cool.  Bruce Thigpen 3d prints counterweight beams for his ET2 tonearms.

I have been printing some audio components here and there.  What filament did you use?

Hi! The black parts are from polymaker polylite pro and the shiny bronze parts are colorfabb bronzefill, which I sanded and polished to get the metal shiny look. I love that filament!

The headshell is also made from bronzefill, which I designed to have a slight recessed guide so it attaches to the arm tube exactly at 19°. That means no stressing about alignment when installing 🙂

Scott

[mgalusha]

This is really cool, nice job! Looks like a Hagerman Cornet in the background.

[Scott B]

This is really cool, nice job! Looks like a Hagerman Cornet in the background.

Hey mgalusha, thanks! You got it, that absolutely is a Hagerman Cornet II in the background! 👍

[mick wolfe]

Nice piece of engineering all the way around  I really like the way you've incorporated a "saddle" where the arm tube attaches to the head shell. Really locks in that 19 degree relationship. I wish the original Amadeus would have featured a similar approach.

[Scott B]

Nice piece of engineering all the way around  I really like the way you've incorporated a "saddle" where the arm tube attaches to the head shell. Really locks in that 19 degree relationship. I wish the original Amadeus would have featured a similar approach.

Thanks, Mick! One of the goals was to tweak areas that I wished had been included in the original design. Another thing I wanted to do was to make it easier to change the VTA without messing up the silicone/golf ball relationship. With the Simplex, if you wanted to raise the arm pillar to adjust the VTA, you had to readjust the cup height all over again. But with this design (and I believe with the LTD arm too), you can raise and lower the whole thing without worrying about messing up the sweet spot of the cup height all over again. 

[mick wolfe]

You're welcome. I've marked the arm post and silicon vat with scotch tape to reference and assure both are equally adjusted. That said, your design puts that method to shame.