"MS Mini" Basic Mid Side Board

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mediatechnology
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"MS Mini" Basic Mid Side Board

Post by mediatechnology »

"MS Mini" Basic Mid Side Board

Update September 9, 2021. The construction thread is located here: The construction thread for the Mid Side Mini is located here: viewtopic.php?f=7&t=1272

I've had a basic MS board on my list to replace the original I did over a dozen years ago.

The "MS Mini" incorporates the Mid Side gain offset capability of the MSII.
Using jumpers, Mid Encode level can be attenuated 6 dB [(L+R)/2] and an offset gain of +6 dB applied on decode to maintain MS ratio.
Using a jumper and an IC change (IC6 1240 or 1246) Side Encode level can be boosted 6 dB with a decode offset of -6dB.

Gain offsets in the Mid, Side or both Insert Sends present more-balanced levels to outboard gear.
Side is particularly level-challenged often being 10-20 dB below Mid.

The MS-Mini's decoder, identical to the MSII also prevents M+S and M-S from producing 2L and 2R.
This avoids having to incorporate a -6dB stage to maintain unity gain.

Image
MS-Mini PC Layout

The board is about 3.7" by 2.75".

I'll be ordering them in the next day or so and should have a small run in about 10 days.
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mediatechnology
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Re: "MS Mini" Basic Mid Side Board

Post by mediatechnology »

This is the schematic for the "Mid Side MIni."

Image
Mid Side MIni Compact MS Encoder/Decoder
emrr
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Re: "MS Mini" Basic Mid Side Board

Post by emrr »

Nice
Best,

Doug Williams
Electromagnetic Radiation Recorders
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Re: "MS Mini" Basic Mid Side Board

Post by Gold »

I still have a pile of the V1 PCB's that I get good use out of. This is a nice addition to the line.
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mediatechnology
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Re: "MS Mini" Basic Mid Side Board

Post by mediatechnology »

Thanks guys!
I'm expecting a small run of boards to arrive in the next hour or so.
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Re: "MS Mini" Basic Mid Side Board

Post by mediatechnology »

Just in...

Let's see if it runs.

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Mid Side Mini PC Board
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mediatechnology
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Re: "MS Mini" Basic Mid Side Board

Post by mediatechnology »

Works great!

The construction thread for the Mid Side Mini is located here: viewtopic.php?f=7&t=1272

Image
MS Mini PCB Assembled

Left > Right Crosstalk Full Encode/Decode

Image
MS Mini Crosstalk L Into R

The full encode/decode 20 kHz unweighted noise level is about -96 dBu.
The dynamic range is 123 dB with +/-15V supplies.

Image
MS Mini Noise Level 20kHz BW Full Encode Decode
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