The SqueezeOhCaster ---- Installing A Mic Into This Stomach Steinway wFotos

[RufusLeakin]

I got tired of clipping a mic onto the front of this little box, so I decided to do a little surgery and see if something a bit more convenient can be designed.

The mic is a gently used, most likely discontinued, Shure SM11 omni dynamic lav (dznt require phantom).

I decided to maintain the mic's balanced XLR output.

All in all, a fun install -- first time I ever something attempted this.

The Unsuspecting Victim




Hole Drilled For The Chassis Mount XLR - Connector will be attached with machine screws and nuts





OmniDirectional Mic Installed Facing Treble Side

NOTE: Sound is reasonably balanced as the treble side of the keyboard is a bit thinner than the bass side, and I wanted to stick with a single point source to capture the sound







Close Up Of My Stitchwork - The Mic Sits On A Foam Pad And Is Secured To The Grill With A Tie Tac Style Mic Clip







3 Fotos: XLR Soldering & Fitting -- Tight Clearance For Sure






Volume Control 10kΩ Linear





Wiring Diagram For A Low Impedance (150Ω) Mic


Arrow Points To The Tic Tac That Secures The Mic . . . . . Just To The Lower Right Of The BlueGold Logo





SqueezeOhCaster In Action


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[Waldo]

Nice work. Is that vintage wiring lace you used? A Paolo Soprani, I assume.

 

[JerryPH]

Good work, looks clean and functional. I think the only thing I would have changed is to use a MINI XLR instead of the full sized one, makes for a smaller hole. Just a fast comparison in size between the two:



So, what does this mic sound like in a recording?

 

[Ben-jammin]

Looks like a clean install. I’m curious why you decided to go linear for the pot. Most volume controls in audio circuits use logarithmic pots as the relationship between audio amplitude and perceived volume is not linear. When a linear pot is used it usually makes it so something 0 to 90% of the volume is controlled by the first 20% of the knobs turn.

 

[debra]

Looks like a clean install. I’m curious why you decided to go linear for the pot. Most volume controls in audio circuits use logarithmic pots as the relationship between audio amplitude and perceived volume is not linear. When a linear pot is used it usually makes it so something 0 to 90% of the volume is controlled by the first 20% of the knobs turn.

You are right that logarithmic is better in general, but that is assuming that the load has very high impedance. If the load is something like 600 Ohms then the linear 10K pot actually only gives you about 10% of the signal when you're already half way up... The load can vary a lot depending on the amp that is used, and as a result the "behavior" of the pot then varies a lot as well, resembling logarithmic with low impedance amp input and linear with very high impedance amp input.

 

[RufusLeakin]

Thanks everyone for your encouragement and comments -- this turned out to be more of a happy experiment that turned out well.

@Waldo - Thanks -- yuhp vintage Woolworth's thread (brings out the treble) and I agree with you, Paolo Soprani

@JerryPH - my initial intention was to install a mini XLR connector on the box and solder up a suitable cable as I had all the parts.

I also toyed with the idea of using a surface mount XLR.

However, once I started getting into nitty gritty of the install I saw that it would be possible to go standard full size. I like being "cord compatible" with the majority of the music world.

Mini XLR's compared to Standard Male XLR Chassis Connector



Surface Mount Standard Male Connector -- this was also a possibility



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@Ben-jammin @debra ----- Linear vs Audio taper - I received some advice from some of my more electronically knowledgeable friends (I know just enough that I need to keep a fire extinguisher nearby).

I use an older Fishman Loudbox Performer PRO-LBX-700 which has balanced mic inputs as well as high imp guitar inputs.

My circuit is passive and balanced and the consensus for this application seemed to be either 1kΩ or 10kΩ linear - I tried both and the 10k seemed to function better and gave me more control; altho the differences between the two values seemed pretty subtle

-- and FWIW I recently tore apart a pretty junky ancient Ernie Ball Volume Pedal and installed a long shaft 10kΩ.

That pedal will be used on a box that I prefer not to poke holes in -- master plan: fabricate a low profile external bracket, install it with velcro and put mics, volume and connector on that bracket. We shall see . . . . .

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