Making The Vintage Amp Safe

Made the new Gibson safe with a 3 prong grounded plug yesterday. I talked with a buddy of mine who is a vintage tube amp guru and he suggested very highly that I get a grounded plug on this thing pronto and also remove the 'death cap' as well.

I did a bunch of research on how to get that done and went to work.

The cord is a 15 foot extension cord from Home Depot with the end cut off. I then made the necessary mods to the inside of the amp and installed the cord. That allowed me to also desolder the death cap at the same time.

The results are very good. Less buzz and a safe amp at the same time!

Finally A Good Blues Rig!

I've been playing through a series of different solid state amps for some time now. I've learned how to get the best tone from them, but at the end of the day, they are not a vintage tube amp, and they don't have the tone that I really wanted.

Searching Craigslist and Ebay and other sources had yielded a number of different good amps to buy in the 5 watt range ( Champ 500, VHT Special 6, etc) but every time I'd call on one, it was gone. What I really wanted was a Kalamazoo amp like Greg Heumann sells.

A couple days ago however, a Craigslist add popped up for a Gibson Skylark GA-5T. Looking it over in the add, it sure looked like a Kalamazoo. Some Googling yielded that it was made in the Kalamazoo factory. I don't yet know however if it is exactly the same circuit. More Googling to be done on that.

So I headed out to the shop and they had the amp. It was/is in awesome condition. I played it and several other 5 watt amps and this one beat the others hands down in the tone area. Price wise, I think they had it underpriced by about half- that did not bother me a bit. I walked out the door with the amp and its in my woodshed now for some playing. I'm still learning how to get the most out of it, but its got tone for days!

 

Opening up the amp, I can tell first that the covers have never been off, and that its never been worked on. This amp is perfect, just like it left the factory.

 



More Progress On the New Mic....

So I made some more progress on this mic.

First up, I had to find a good pot (potentiometer) for the volume control. That took a bit of doing. I ended up with a 5 meg ohm pot that I bought from Digikey. Pricey little thing, but it had a 22mm (basically 7/8") long shaft, which was necessary to get through the body of the mic. It also has a very small body itself, which fits behind the element nicely.

To make this fit, I had to drill out the hole that was previously used for the ground. This started as a hole for a 6-32 screw, and I progressively enlarged it with increasing bits up to the 1/4" hole needed for the pot. For those that have never seen one of these before, I'm putting a volume knob in the hole where the mic body would have been mounted on a post in its stock configuration.

The 'Before' picture.

 

And the 'After' Picture.

 

After that, I needed to drill out one of the molding posts to make a new ground. I actually decided to drill two of them before I painted it. Just in case I wanted to ground the pot and the element to opposite sides for some reason, or the tapping of one failed. I tapped this again for a 6-32 screw.

 

 

 

Now it is time to wire this thing back up. A couple minutes with my multimeter told me which pins on the pot were for control and which was ground. I soldered up the circuit. For those that I don't plan on desoldering for paint, I went ahead and heat-shrinked them. I left the others bare. Everything fits pretty nicely. I'll change out the wire coming from the Amphenol connector to a white wire for 'signal' to allow easy understanding of the circuit when I rebuild that portion.

 

 

With the wiring done, I was able to screw the thing back together and give it a go. I stole the knob off my other nice mic to give it a try (I ordered some good 1/8" post knobs that should arrive tomorrow that will go on this mic).

 

Results with the 5 meg ohm pot are dead on and exactly what I wanted. No tone change, just volume change.

 

Crushed blue velvet 'silk' to protect the element. 

 

 



 

 

Building A New Mic!





 

I've been looking for a new project, and decided to build myself a new harp mic. Don't really need one, but I wanted to build something new, so it was time. I found this one on Ebay and paid a good price for it. Looked pretty ugly when I pulled it out of the box, but it did have an element inside.

 

I was not sure if the element would work, but I was pleasantly surprised when I found that it did. Not only did it work, it sings! It has a great tone with my amp. Similar to the vintage crystal Astatic element in the Purple mic I built a few years ago. The element in this one is a Calrad C-3. Japanese made and has a good gasket with it.

 

For this one, I plan to clean it up, install a volume control, lay some cool paint and then do automotive clear on it. Unfortunately, the clear I laid on the Purple mic was just too delicate. I may also lay some Auto clear on that mic at the same time.

 

Here are the before pics.