standalone ms matrix

[jg1983]

Hello forum.

Slightly odd question but here we go...

Does anyone know of a device I can plug my mid and side mics into BEFORE they arrive at the preamps?

I'd like to be able to plug an MS mic into my Mackie mixer and mix with other mics and then record on the fly to stereo. But the mixer obviously doesn't have an MS decoder built in (unlike the 8-channel Onyx rackmount pre...). To keep costs down, I was wondering if a device existed that decoded a signal at mic level, rather than line level, so I can use the preamps I already have and not have to buy more preamps with an integral MS decoder?

I did search the forum but couldn't find anything.

Thanks...

Jonathan.

[NorseHorse]

I'm not familiar with anything like this. I mean, how much gear (other than preamps) EVER deals with signals at mic level?

[Matti]

Use 3 channels of your Mackie

Matti

[jg1983]

Thanks for the replies. I was just hoping that perhaps something would exist to let me use the equipment I already have without buying more.

As you suggest MATTI, that a mic splitter and three channels would work. But since I have only four preamps in my mixer (Onyx 1220) I'm one channel short because I'd like to have an MS main pair and omni outriggers.

Maybe it's time to buy the Mackie Onyx 8-channel rackmount preamp and have done with it.

(I was thinking of selling my Onyx 1220 and replacing it with a four channel ENG mixer like the Sound Devices 442 because that has everything I need in a really small package....... ....but then I saw how much it costs...)

Jonathan

[NorseHorse]

If you're doing CRITICAL/CLASSICAL type stuff, there are several rackmount preamps that have M/S.

Grace m201
Mackie Onyx 800
True Systems Precision 8 and P2Analogue
Amek 9098
Universal Audio DCS

Smaller names like Forsell and even Great River and Millennia should be able to add an M/S matrix to any of their dual channel pres if you asked nicely (and sent them some money!).

[stuntbutt]

Well an MS mic is going to have a built in matrix for Left/Right. If you are doing MS with two seperate mics, then the problem is the lack of polarity switch on the Mackie.

You could use an outboard matrix at line level via the channel inserts.

You could make up some special cabling and use three channels on the Mackie.

[Matti]

It seems the recording outs are balanced so you could make a special cable
from the DB25 connector to one of the stereo inputs to make the "side" channel,
tidy and neat

Matti

[jg1983]

Thanks a lot for suggestions.

You could use an outboard matrix at line level via the channel inserts.

That never even crossed my mind! But so simple. That would work. It is after all what the inserts were made for!

Do you know of any decent portable line-level ms matrixes? I've had trouble finding any that are in production.

It seems the recording outs are balanced so you could make a special cable from the DB25 connector to one of the stereo inputs to make the "side" channel, tidy and neat

...another "why didn't I think of that" moment...

[c.gymer]

Head on over to the Electrical Audio message boards (Electrical Audio :: View Forum - Tech Room) and ask Greg Norman about the EA matrix that he is building. They are very good and hand made by Greg.

[Corran]

If you use an XLR Y-cable (one female to two male) and a phase reverse plug, the mid mic should be good to go into two different channels, right? This is how I've done it for a while. I asked if splitting the mid mic with a passive splitter was bad or not a while ago but I was told it was not a big deal.

[jg1983]

What's the deal with phantom power with the Y cable? Presumably if my mixer has only a global phantom power on/off switch (which mine doesn't, luckily), sending 48V to the mic from both inputs of the mixer won't damage the mic?

I was wondering about the mic splitter thing. Jensen have a very informative article about them here:
http://www.jensen-transformers.com/an/an005.pdf

Does the fact that one of your two splits must be transformerless in order to pass the phantom power make a difference to the sound between the two channels? Presumably it does because one split would be transformerless whilst the other would have to pass through a transformer? I'm guessing this is not good since the two side channels should cancel each other out when mixed together, and that can only happen if the signals are identical?

I still cannot find a reasonably priced mic or line level passive or active decoder with a width control. A Sound Devices 302 would solve my problems with a couple of extra handy features, but at a price.

I'd make my own using Jensen transformers if they weren't so expensive. It's not the price that's concerning me, it's the risk. I'm not an expert in electronics, so I wouldn't want to pay for a pair of transformers without being confident of building something that worked reliably and at a good quality.

Jonathan.

[Matti]

Originally Posted by MATTI

It seems the recording outs are balanced so you could make a special cable
from the DB25 connector to one of the stereo inputs to make the "side" channel,
tidy and neat

Matti

He doesn´t want to lose any mic preamps, so I would do that with the direct
outs and one stereo channel ( and the levels of side channels would always be
ok between them )

Matti

[jg1983]

It seems the recording outs are balanced so you could make a special cable
from the DB25 connector to one of the stereo inputs to make the "side" channel,
tidy and neat

Matti

This does seem to be the 'cleanest' solution for now. Using the F/W outs, I can then make a backup multi-track to a DAW with the MS signals whilst at the same time making a mix with the encoded AB signals for the main recording.

Jonathan