Calling SSLtech, any SSL gurus...

Hey dudes!

Just a curious question concerning the SSL4000 and 6000 circuits.

On a 4000 in the stereo aux returns there are controls for level (stereo), balance and interestingly width.

This width control also crops up on the more featured SL611S stereo I/O module. Its in the channel section labelled image above the pan and can be turned on/off and has options for extra wide and also additonal filter switch to ensure anything below 250Hz isn't made too wide.

My questions are this:

Do you ever use this on an SSL? Find it too easy to do damge?
This has to be some form of M/S circuit and me likey!! So does anyone have a schemo?

I particularly like the way the stereo channel deals with positioning and could be great for mono'ing out reverbs/pads and panning them off...or enhancing the width of some delays.

I wouldn't mind cribbing a look at the circuit as I have have lost access to a 6000 manual

Cheers Tom

[quote author="TomWaterman"]Hey dudes!

Just a curious question concerning the SSL4000 and 6000 circuits.

On a 4000 in the stereo aux returns there are controls for level (stereo), balance and interestingly width.

This width control also crops up on the more featured SL611S stereo I/O module. Its in the channel section labelled image above the pan and can be turned on/off and has options for extra wide and also additonal filter switch to ensure anything below 250Hz isn't made too wide.

My questions are this:

Do you ever use this on an SSL? Find it too easy to do damge?
This has to be some form of M/S circuit and me likey!! So does anyone have a schemo?

I particularly like the way the stereo channel deals with positioning and could be great for mono'ing out reverbs/pads and panning them off...or enhancing the width of some delays.

I wouldn't mind cribbing a look at the circuit as I have have lost access to a 6000 manual

Cheers Tom[/quote]

I've seen the width too on our SSL (4000 E/G+) and wondered about it. Any light would be good. Also, the feedback knob!!! :green: How cool!

hmmmm it's been a long time since i used an SSL with a stereo channel in it. As for the reverb returns and the width control hmmmmm.. To be honest I never really engaged that function but IIRC it's not an M/S type function by a long shot... I have the 4000 manual @ work... I'll look up the stereo returns and see what I can dig up. Where is keef with the answer :?

I have a stereo module here... and a manual.

I'll take a look sometime, but it's just a reverse-polarity crossfeed from what I remember. It surpresses center information (try it with a mono signal and see what I mean!), widens 'half-panned' stuff to the sides, and makes hard-panned things appear opposite-polarity in the other channel.

yes, it's good for sidening narrow things, but for full-wide things, it causes loss of level when thngs get summed to mono... use with caution/taste.

Keith

[quote author="SSLtech"]I have a stereo module here... and a manual.

I'll take a look sometime, but it's just a reverse-polarity crossfeed from what I remember. It surpresses center information (try it with a mono signal and see what I mean!), widens 'half-panned' stuff to the sides, and makes hard-panned things appear opposite-polarity in the other channel.

yes, it's good for sidening narrow things, but for full-wide things, it causes loss of level when thngs get summed to mono... use with caution/taste.

Keith[/quote]

Surpresses center info? like when you put a stereo signal mono and flip phase on one of the channels :?

[quote author="pucho812"]Surpresses center info? like when you put a stereo signal mono and flip phase on one of the channels :?[/quote]
Well, yes, but without the mono step... no need for it, you see...

You can do EXACTLY the same thing with 4 mono modules:

Mult the signal to two L/R pairs. Pan the second pair OPPOSITE the first. (so if Left signal is fed to modules 1 and 3, and Right signal is fed to 2 and 4, pan 1 left, 2 right, 3 right and 4 left.

Now, put faders 1&2 at unity/zero on the fader, and play the music.

To progressively NARROW the image, bring up faders 3&4.

To progressively WIDEN the image, bring up faders 3&4... but with the polarity reversed on modules 3&4.

Same rules apply, same exact result: It widens 'half-panned' stuff to the sides, and makes hard-panned things appear opposite-polarity in the other channel. Center stuff gets quieter... At equal fader position ("full-wide") the center disappears... hello vocal reverb, goodbye vocal!

Eez seempul, -no?

Keef

[quote author="SSLtech"][quote author="pucho812"]Surpresses center info? like when you put a stereo signal mono and flip phase on one of the channels :?[/quote]
Well, yes, but without the mono step... no need for it, you see...

You can do EXACTLY the same thing with 4 mono modules:

Mult the signal to two L/R pairs. Pan the second pair OPPOSITE the first. (so if Left signal is fed to modules 1 and 3, and Right signal is fed to 2 and 4, pan 1 left, 2 right, 3 right and 4 left.

Now, put faders 1&2 at unity/zero on the fader, and play the music.

To progressively NARROW the image, bring up faders 3&4.

To progressively WIDEN the image, bring up faders 3&4... but with the polarity reversed on modules 3&4.

Same rules apply, same exact result: It widens 'half-panned' stuff to the sides, and makes hard-panned things appear opposite-polarity in the other channel. Center stuff gets quieter... At equal fader position ("full-wide") the center disappears... hello vocal reverb, goodbye vocal!

Eez seempul, -no?

Keef[/quote]

yes. yes it is...

Aha! thanks Keef!!!

I knew you'd come through - and thanks Pucho for kicking it off!

So its not at all what I expected and not as useful to me as I would have thought.

I think I'd prefer a M/S width control with standard stereo balance or pan.

The reason I thought it might have been M/S based is because the stereo channel accepts sum/diff signals or standard L/R.

-T

Yep - I'm intrigued about width controls on m-s encoded/decoded gear.
Maybe TedF would be as so kind to explain how it is implemented in his compressor - I think the P38 :?:

Have you seen these?

http://www.bbc.co.uk/rd/pubs/archive/pdffiles/monographs/bbc_monograph_38.pdf
http://www.uneeda-audio.com/ms-mat.htm

-Tom

You can achieve the same result by doing an M/S conversion, then a detented balance control, then an M/S conversion.

At the detent, in=out.

At full one way, All M (mono), no S (sides).

At full the other way, all S (side) = super-wide, and no middle... hence center suppression.

I have now sent the stereo module back, so no piccies I'm afraid, but I do still have the documentation.

Keith