DIY amp and such build gallery

[Fitz]

Thanks guys. It's definitely doable, although extending the shaft was a real pain because of how close the tolerances need to be.

[n_maher]

Too bad I only have one left.

[spritzer]

Here is the chassis mostly done on what will become a variation of the Egmont. I'm going to build this as cheaply as is possible so I'm going to stick with the ECC83 (I have a bunch of them) and use 6S4A's for the output duty since I have a lot of them as well. The stock Rudistor Egmont runs on a single +/-260v rail which is fine for the ECC83 but the 6S4A needs more voltage so I'll have to cram two separate PSU's into that tiny chassis. Should be fun though.

[n_maher]

Looking good!

Personally I've vowed to never again use a rear panel power switch if I can help it. I nearly burn myself every time I have to shut the Menace off.

[spritzer]

I like to have all the power stuff on the back panel to have less high current AC floating about the amp section. It also means less clutter on the front which suits me just fine.

[guzziguy]

Originally Posted by spritzer

<snip>
The stock Rudistor Egmont runs on a single +/-260v rail which is fine for the ECC83 but the 6S4A needs more voltage so I'll have to cram two separate PSU's into that tiny chassis. Should be fun though.

Will you have room for the boxes to cover all the sections in the box so that it looks authentic?

[spritzer]

Originally Posted by guzziguy

Will you have room for the boxes to cover all the sections in the box so that it looks authentic?

I'm sad to say no since the normal Egmonts come in the 40mm variation of this chassis and there simply isn't room for the ....ehhhhh...."extra shielding" there. This is the 80mm version so I have more room but most of it will be take up by the caps, two R-core transformers, the delay circuits for the B+.

Btw. Has anybody ever tried to use the sides of these Galaxy cases as heatsinks and if so how much powahhhhh they can handle? The plate resistors on this thing are tiny so no problem there but mounting the regulators to the sides would safe a lot of space.

[n_maher]

I wouldn't expect the sides to be all that good as heatsinks since they don't have that much more surface area than just flat material and the slots are horizontal so they won't flow great. How many W do you expect to have to deal with? And the other downer is that you won't get much if any thermal sharing between the top and the sides.

[luvdunhill]

Originally Posted by spritzer

Btw. Has anybody ever tried to use the sides of these Galaxy cases as heatsinks and if so how much powahhhhh they can handle? The plate resistors on this thing are tiny so no problem there but mounting the regulators to the sides would safe a lot of space.

I have some balanced buffers stuck to the side of my KGSS Galaxy case. I think you could probably get a few watts per side.

[spritzer]

I haven't done the math yet but it's not much that they will be required to cope with. I've seen Rudi do it on a few amps but that doesn't say much.

Thanks Marc for clearing that up for me.

[n_maher]

I'd agree about the few watts per side number and also it would seem like something that'd be pretty easy to monitor to makes sure you don't get a localized hot spot. An infrared thermometer would be quite handy if you've got one.

[luvdunhill]

Originally Posted by spritzer

I haven't done the math yet but it's not much that they will be required to cope with. I've seen Rudi do it on a few amps but that doesn't say much.

Thanks Marc for clearing that up for me.

it's worth a shot I say. Otherwise, just mount the regulators on heat sinks on the top of the case like many do. I think that looks pretty cool myself. How close are you to flipping the switch?

[spritzer]

Originally Posted by n_maher

I'd agree about the few watts per side number and also it would seem like something that'd be pretty easy to monitor to makes sure you don't get a localized hot spot. An infrared thermometer would be quite handy if you've got one.

I have one of those so I'll do that or just let them be exposed on top like Marc suggested.

Originally Posted by luvdunhill

How close are you to flipping the switch?

Depends on my free time and when the R-cores get here. I could scrounge parts for two old BH PSU's set for the right voltages and use the BH filament trafo to test the amp though. The only thing I could do tonight was wire up the IEC, fuse and power switch...

[pabbi1]

OK, the latest group grope - balanced Bijou:

http://home.swbell.net/pabbi/bijoufinal1.jpg

I had lots of help on this one, mainly because I rule as a DIY idiot. But, it sounds very sweet now that the tubes (6n1p input, 6n6p output, and ez81 rectifiers) have settled in.

Pity very few have a chance to hear them. It is the most _musical_ amp I have - der Staxen please forgive me.

[spritzer]

Looks great but needs moar blackgates!!!

[Vortex]

Originally Posted by spritzer

Btw. Has anybody ever tried to use the sides of these Galaxy cases as heatsinks and if so how much powahhhhh they can handle? The plate resistors on this thing are tiny so no problem there but mounting the regulators to the sides would safe a lot of space.

The side profiles of HiFi-2000 enclosure can serve as heatsink for couple of regulator very well.
In this amp, the two ±24V regulators are mounted on the side profiles (40mm H x 280mm L).
In all conditions, the regulators/heatsinks never get warmer than 40 degrees C.

[spritzer]

Thanks for the info. I'm still wiring up the amp section (had to get a bit creative with the Wima coupling caps) and there is a BH Hybrid PSU ready for a test run when I have the time. I should fire up the filaments before I do anything more though...

[Fitz]

Vortex: How many watts is each of those regulators dissipating?

[Fungi]

*injects some noobishness into this thread*



Still missing some parts...

[Beefy]

Originally Posted by Fungi

*injects some noobishness into this thread*

Looking good! But here's a tip......

Bend the legs of the Vishay Dale resistors so that the part number faces up when mounted on the board. It makes it much easier to troubleshoot in the event that something goes wrong. Same for any other part that uses a text label instead of colour bands.