My Ruby is on the way! (pics)

[syndromet]

As I told you yesterday, I was gonna start building the cabinet for my stereo Ruby today. It will be suited in a little suitcase, and it's starting to look good.
The controlls for each amp will be:
           power on/off (spdt toggle)
           Internal/extern speakers (2pdt toggle)
           Gain pot (w/ chickenhead knob)
           Volume pot (w/ chickenhead knob)

The controll panel will be mounted on a metal plate above the speakers( shown with white paper)

Showing the parts


Case closed


An illustration of what it will look like


Showing the size with a regular cd (You should check out that album if you like metal!!!)

So, here comes the questions
1. Shielding
The suitcase is made of some kind of paper, and should not provide shielding at all. Is the ruby sensitive to interference? What would be the best way to shield the box. I'm thinking of putting the circuit in a small metal box. Would it be possible to glue tin foil on the inside of the box for shielding? What would you have done?

2. Drilling the holes for the speaker
How do I do this? I don't have a router...

3. Battery
Anyone have a good suggestion for where to place the battery?

4. Opinions
What do you think?

[Herr Masel]

1. I think you will need to cover the interior of the suitcase with aluminium foil, or place the circuit in a metal box. Someone was talking about a shielding compound that comes in the form of a spray can.

2. Just use a drill...

3. I think the battery should have plenty of room inside that suitcase! Just duct-tape it to the bottom or something.

4. It looks very nice. I want to build an improved ruby and use it for busking (I'm not a bum , I just like street culture and street musicians), using a suitcase for that application would be great.

[syndromet]

Thanks for the advise Herr Masel.

I guess I have come as far as I can right now. Next step is finding a place where I can get a metal plate for the controlls, and wait for the parts to build the electronics in there...

I remeber someone her was talking about using batteries ment for RC planes in their pedals? I'm thinking of running this Ruby on 12V, and was wondering what battery would power this thing for the longest amount of time? I think it will suck regular batteries empty almost before powering it up, as it is two amps running on 12 V. Any sugestions?

[syndromet]

Anyone else think it looks like an old reel-to-reel tape recorder? 

Noone have any tips on what batteries I should use?

[B Tremblay]

I've used plastic boxes for 386-based amps like the Ruby and have had no issues with interference.  Also, there's a very good chance that the aluminum foil will vibrate audibly.

[Ge_Whiz]

Yeah, I built mine in an MDF box and used screened cable for off-board wiring. No noise issues.

I keep recommending the use of rechargeable 12V gel-cell batteries for this build - mine runs for hours on a small one - but it seems that, just like veroboard, the USA hasn't yet got up to speed with 20th Century technology... 

[TheBigMan]

If you're going to use batteries I'd suggest a 12V pack of AAs rather than a 9V.  I actually run my Ruby at 18V for maximum clean headroom.  I've got another Ruby as a headphone amp in a plastic belt clip case (Must post some pics of that one!) and there's no added noise over the other one in a metal enclosure.

Are you using a switch to route the signal between a speaker out jack and the internal speakers?  If so, I'd use a switching jack instead so that the internal speakers are disconnected when you stick a plug into the jack.

Your local DIY shop will sell holesaws for your drill, they'll make large round holes.

Finally, looks awesome!  If you check the archives there's a mini-amp pictures thread somewhere, you can see what other people have done with these brilliant little amps.

[RLBJR65]

That looks very cool

BigMan's suggestion works very well. Use 8 AA, C or D batteries in series for 12V. The bigger ones usually last longer but whatever you have room for.

I used to live less than a 1/4 mile from a 50,000 watt transmitter. If I used ceramic caps I could hear our crappy local radio station perfectly through my 386 amp. After building a couple that way I switched to poly caps and didn't have anymore RF noise. Even stuck a few in plastic computer speaker cabs.

I'm sure you will enjoy it very much when your finished. The Ruby is a great sounding little amp!

I like to use an ROG Fetzer Valve in mine as a pre-amp. If you use 12V all you have to do is adjust the trim pot so you have around 6V at the drain.

Richard

[syndromet]

That looks very cool

BigMan's suggestion works very well. Use 8 AA, C or D batteries in series for 12V. The bigger ones usually last longer but whatever you have room for.

I used to live less than a 1/4 mile from a 50,000 watt transmitter. If I used ceramic caps I could hear our crappy local radio station perfectly through my 386 amp. After building a couple that way I switched to poly caps and didn't have anymore RF noise. Even stuck a few in plastic computer speaker cabs.

I'm sure you will enjoy it very much when your finished. The Ruby is a great sounding little amp!

I like to use an ROG Fetzer Valve in mine as a pre-amp. If you use 12V all you have to do is adjust the trim pot so you have around 6V at the drain.

Richard

I have been thinking about using Fetzers as preamps. Thanks for the tip about biasing to 6v.


How do I wiri up switching jacks?

[TheBigMan]

There are four connections on the jack.  The nearest two are taken from the circuit, the furthest two go to the speaker.  When a plug is inserted the connections on the top are lifted and break the path to the internal speakers, disconnecting it.

If you follow the link in my sig there's a verified stripboard layout for the Fetzer-Ruby.

[syndromet]

Looks like switching jacks is on my "to-order-list"!! That is a great idea.
BigMan, I've been planing to use your fetzer-ruby layout since I started this project.

I have now bought a gel battery, but it was just a little to big to fit it in the box. Think I'm gonna use it as an external PS.

Thanx for all the help this far!

[syndromet]

So, I have decided to go for switching jacks to turn of the internal speakers when adding an external cabinett.
As told before, this is two rubys in one box. I'm now trying to figure out how I can run both speakers in series for 8 ohm when only running the first amp, but one speaker for each amp (4 ohm) when both both amps are engaged.. Anyone have any good ideas?