Pluto - Done ! (With A design variation)

[vu2qx]

Hi

Yes ! I finished my Pluto project. Here is the story.

First, shopping for pipes and fittings. Got everything except the 4" to 5" Fernco Rubber coulper. Could not locate a replacement part made of rubber. Hence I decided to go for an all-PVC (well, almost) construction.

So, here is the starting point:



Everything except the top and bottom portions of the 4" pipe and botton portion of 2" pipe is exactly as designed by SL. Instead of the rubber coupler at the top, I decided to use a PVC coupler. And instead of the wooden base at the botton, a larger (4" to 6") PVC coupler will be used. For stability, I filled the base coupler with cement and sand mixture (1:4) and allowed it to dry for a couple of days. That makes a stable, heavy base - and gives an all-round form which I like better than the box in the original design.

Next, I sanded and primed everything:

DSC01615.JPG

Yes, you can see I have already started playing with colours. Painted the base black and I liked it. How would black and chrome look?



How about copper instead of chrome ?



I settled for Copper.

Mounting the woofer on PVC coupling posed a challenge. Solution was a custom made ring made out of MDF. It is designed to fit tight into the coupling and provide a neat mount for the driver. Got it done by one of the CNC shops:



Here are a few pictures to show the details:




The two pipes are joined at the bottom in this fashion:


These stainless stell fittings will be used to connect the pipes together at about 30" high from the bottom.


These are strong and also provide a neat way to route tweeter cable into the 4" pipe. However It needs to be closed with silicone gel to prevent air escaping into tweeter pipe.


Amplifiers will be placed along with rest of the equipment at the back of the room. I decided to use speakon connectors mounted on the base to connect to amp. These connectors are easy to use and quite rugged:

Yes, the gaps around the connector needs to be sealed tight as well.

Everything is ready for final assembly:


In progress...



And finally:


Now on to the electronics part. Both amplifiers were completed and wired up to the test setup. I used Speaker Workshop to generate test tones.



Well, I had my share of excitements ! 100HZ test failed on TP5 itself. OK, missed the shorting wire in place of C3. Got that fixed. Then TP6 failed on one of the boards. OK, that was becasue one of the pins of U2 was not soldred. Got that one fixed as well. 100Hz and 1KHz readings were done alright with DMM. However, it was not good enough to measure 5K and 10K test signal. It was time for oscilloscope. All tests were good ! Mission completed ! Time to sit back and enjoy !

Regards,
Jay

[kjen]

Very nice job Jay.
That is a really interesting shape and they look good in the copper color. I ended up with black and aluminum, I considered copper/gold but that was almost as much a negotiating position for the family to shoot down

I had a few items to debug with the boards as well (2 dry joints, 2 solder bridges, and one loosely seated U2 chip - I think). SL's test points worked very well for localizing problems.

Kevin

[vu2qx]

Thank you, Kevin. Yes, I played with a few colors, but settled for Copper. It went well with the color scheme of the room so I did not have to do much of convincing

And yes, voltage readings at test points immedietely pointed to faulty stages.

Overall, it was a fun project to do and quite rewarding in the end. And I already have my friends wanting a pair for themselves ! Well, more fun lined up !

Cheers,
Jay

[Bill Schneider]

That's very attractive!

I like the copper color, especially in the room pictured. The round base design simplifies the appearance of the Plutos, and adds a nice symmetry to the look.

Very nicely done! Now comes the question -- how do they sound?

Bill Schneider

[cameronthorne]

Jay,

Very well done. I think yours is one of my favorite PLUTO variations that I have seen to date. What process and materials did you use for painting the PVC? How much do they weigh?

I have thoughts of one day building new enclosures for my own PLUTOs if they ever change to a different room, so I am collecting ideas.

-- Cameron

[roehrig]

Jay,

Round, rounder, roundest! I like your Plutos very much.

Steve

[vu2qx]

That's very attractive!

I like the copper color, especially in the room pictured. The round base design simplifies the appearance of the Plutos, and adds a nice symmetry to the look.

Very nicely done! Now comes the question -- how do they sound?

Bill Schneider

Thank you, Bill. Yes, I liked the symmetry of the shape. It makes construction easier too.

How do they sound ? I listened to SL's pluto's in his house and I think these sound very similar. For listening to music, I move my chair up close to the sweet spot. I am happy with the sound stage created. I like the mid ranges better on Plutos, compared to the floor standers that used to be in their place. Violins, Pianos, Vocals, Snare drums.. all sound more lively on Plutos. Pluto's by themselves (without sub-woofers) are quite adequate for music that's largely mid/high oriented. With sub-woofers on, they rock !

-Jay

[vu2qx]

Thank you Cameron and Steve.

Cameron, here is the process I used to finish PVC pipes:

1. Sand, Sand, Sand. Started with 100, finished with 400, if I remeber right. Get a uniform, scratch-free, matt finish.

2. Acrylic Primer. I applied two coats. I brushed it on and quickly applied a roller to get an even finish.

3. Automotive spray paint made by Bosny:

(No.1139, Metallic Black and No. KT-180, Copper)
It was not easy to get this right. Two parameters decide how good the job is: The distance between the can and the surface (I found about 20cm Ideal) and the speed at which your hand moves. Both has to be kept constant for nice uniform finish - a steady hand. It took me a while to get it right. I applied two coats.

As for weight - Each is about 7.5Kg (16.5 Pounds)

-Jay

[grubyhalo]

Hi Jay,

You're Pluto looks amazing! I understand that you have the Orion in your 'to-do' list as well and am very interested in how that shapes up for you as I am hoping to 'DIY' the Orion myself. Also, it's good to know that there's another member in the forum from the same part of the world! Good Luck!

Cheers!

[fazambuja]

Wow Nice!