Modified Pro-Ject Genie3 turntable

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Hey everyone!
I've been here for a while, just reading. Great site, cool people around.
Now, I'm glad to publish here my modded turntable. It's Pro-Ject famous little bargain TT - RPM-1 Genie 3.
My modified turntable has got the new name :) - "Sphere"
OK, why I did this damage at the first place. Because it was something from the beginning I found not right, although I did fall in love with this unit from the first moment I saw it. It was extremely cheap to buy, and was fun to try some modding.
What I found wrong is very light boomerang base especially that left end with the huge hole in MDF where the motor goes.
The left side is just too lightweight and the other where the tone-arm sits quite heavy. Not good at all.
And in front there is half of the 1700 gr. platter always "hanging" free, and (when TT is off) with the small force on the edge of the platter the whole TT falls easily down, to the right. Whoever owns this device knows what I'm talking about ;)
The motor, ah motor, what a piece of toy. It is lightweight and it’s shaking every time when switched on and turns the belt. I was tired to watch this. A friend told me that I bought a toy. So, if toy I've decided to play with it :D
Let me point out that I'm not an electrician or a carpenter lol it is just a hobby.
So, to make the long story as short as possible (but with the images) here’s what I’ve done:
1.Displaced the motor, fixed it inside the metal ring and on the top of extra heavy weight – doorstopper! http://imageshack.us/photo/my-images/59/projectsphere2011motorb.jpg/
Yes, no mistake here lol
2.Closed the hole on the boomerang with a metal bonnet, from the bottom side http://imageshack.us/photo/my-images/263/projectsphere2011bonnet.jpg/
3.On top of it have put the glass holder with the marble sphere http://imageshack.us/photo/my-images/835/projectsphereglassbasem.jpg/
4.Replaced the silly plastic spikes with metal ones. http://imageshack.us/photo/my-images/534/projectsphere2011newspi.jpg/
5.And finally turned the metal RCA output box for 90° to the right – out http://imageshack.us/photo/my-images/15/projectsphere2011newspi.jpg/

+ new cartridge Denon MC DL-160 (something that I’ve done months before this mod)
(more to see here: http://img835.imageshack.us/slideshow/webplayer.php?id=projectsphereglassbasem.jpg )
I am very happy with the final result, however there are some more little details I would like to do in the future (not now, it’s too hot this summer here lol) . I wanted to keep this modding as simple and clean as possible, so no painting new color or such things, just few drills inside the base and glue where it needed and that’s all.
I have achieved that turntable got additional weight of 590 grams. So that gives total of some 3890 grams (excluding the Disc Stabilizer with its 280 grams) and also much better stability.
And finally the most important result is – the sound! Yes, sound is now more tight, cleaner and precise. Nice bass, simply all at the right place J
Turntable is connected via Yaqin MS12 preamp (tubes orig. China 12AX7 and RCA JRC-5814A) to the MengYue (Music Angel) EL84 (vintage Russian tubes 4x6P14P-K + 2x 6N1P-V). LS are Mordaunt-Shorts Avant 902i (and all in very small room). But here is enough room for more “toys” like two CD players, one DVD, another Music Angel preamp,.. OK, that’s it folks. Hope you do like it (or dislike it)?
Just don’t be too cruel on judging LOL
Any questions, comments or suggestions are welcome! cheers!
 
Cool! Thanks for sharing.

I wonder about the platter mat on picture 13, it seems EXTREMELY similar to the IKEA thingy for kitchen, protecting the other thingy. I wonder how the sound is, it was a cool idea, it's a nice alternative to the felt mat.

(sorry for my bad description, I am tired and my english could be better)
 
Cool! Thanks for sharing.

I wonder about the platter mat on picture 13, it seems EXTREMELY similar to the IKEA thingy for kitchen, protecting the other thingy. I wonder how the sound is, it was a cool idea, it's a nice alternative to the felt mat.

(sorry for my bad description, I am tired and my english could be better)

Hi, the mat is made of EVA (Ethylene vinyl acetate) - EVA can be used as a substitute for cork in many applications as a shock absorber, for exp. So as cork mat is quite expensive I decided to give this a try, and it does the work very well, also looks more attractive. What's more, it's always more fun to do it yourself than just buy it
And the original felt mat is not just too thin, it usually sticks to the records - another thing that needed replacement the next day I bought it.
 
The biggest improvement I found was to supply the "toy" motor with a crystal controlled 50Hz sine wave, amplitude 16V.

Jadran how did you remove the plastic spikes? Are they just glued on to the base?

Can you provide the link to this improvement?

Plastic spikes are just silly. I was a bit crazy about those too, there are long screwes on top of boomerang (under the platter) that you need to remove first.
Then spikes need to push-pull on a side (use jaws if they don't go by hand) as spikes are also glued.
On the new metal ones I put the rubber stickers and just glued onto the base.
 
Can you provide the link to this improvement?

Plastic spikes are just silly. I was a bit crazy about those too, there are long screwes on top of boomerang (under the platter) that you need to remove first.
Then spikes need to push-pull on a side (use jaws if they don't go by hand) as spikes are also glued.
On the new metal ones I put the rubber stickers and just glued onto the base.

Attached is schematic, if you use Cadsoft Eagle Cad, you can PM me for files and source code (Designed by someone in Denmark I believe).

I think the spikes on my TT is only glued on as there are no screws on the "boomerang" under the platter.
 

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Attached is schematic, if you use Cadsoft Eagle Cad, you can PM me for files and source code (Designed by someone in Denmark I believe).

I think the spikes on my TT is only glued on as there are no screws on the "boomerang" under the platter.

Possible that on yours are just glued, more so if it's the first model, as they did "improve" later one. But not enough, for me though :D
Here's how it was on mine TT
An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


Thanks for pdf. I'll check it later and PM ;)
 
Hi, the mat is made of EVA (Ethylene vinyl acetate) - EVA can be used as a substitute for cork in many applications as a shock absorber, for exp. So as cork mat is quite expensive I decided to give this a try, and it does the work very well, also looks more attractive. What's more, it's always more fun to do it yourself than just buy it

Hello again.
Thanks for the information, it was really creative. I found more information about "my IKEA mat" : RATIONELL VARIERA article number 800.128.53 . I don't know what sort of plastic it is, I'll ask IKEA someday. DIY is fun! ;)
 
Second modification - Pro-ject Bamboo

I'm lifting up my old thread just to put some new pictures of my second mod on Pro-Ject RPM1.3 aka Genie. The first mod last year was fun but I lack some more courage to do more (I just didn't want to break something). That lightweight boomerang bothered me much all the time, or to be more precise – the resonant ring that surrounds motor, and the motor itself because it’s too light, just 300 g.
So this time I did cut off the ring, fix tight the rest of boomerang onto the new plinth, which is three bamboo boards glued with natural cork in sandwich. So basically the original design with the three cones is replaced with the heavy natural base that sits on three rubber feet.
This time I also have changed really cheap RCA sockets with something much better, and tonearm wire with Cardas and silver plated clips.

Here are few pictures, so perhaps someone could get idea and do something similar with this great wood-like material bamboo. (Must be Moso type)
cheers, Jadran

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Can you describe the sound improvements after your modifications?
Yes, I'm just listening some of the records that I didn't like the sound before and voilà - there are more details, highs not harsh as before, bass tight, fatter and pleasant. Sound is cleaner and dynamic range filled. Although I have to play with two different phono preamps., at the moment I use Hanss acoustics and have nothing but positive words for it. Yaqin MS12B is resting as I'm planning to replace the caps.
I did expect improvement in sound, there are many changes; from the total weight of unit 6,200 g. + 1,400 g. motor with it's base, no more resonant ring that I found absolutely useless, spikes also were not good choice, with the rubber feet stability is assured. Silver plated clips and RCA sockets certainly help to bring more details along with new wire. Cork mat that I also made is much better solution to dampen noise and absorb vibrations.
For what is was before it's like having a completely new TT ;)
 
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