Impressive Mpressor!

What do you guys think?

http://www.youtube.com/watch?v=uzKJ36ovg18

http://www.youtube.com/watch?v=6ZWsCJKGan4

[quote author="fazeka"]What do you guys think?

http://www.youtube.com/watch?v=uzKJ36ovg18

http://www.youtube.com/watch?v=6ZWsCJKGan4[/quote]

Nice RAPressor! :thumb:
Looks like a good feed- forward regulator with EQ. I like design of a faceplate, it is interesting, especially going down meters!

WOW, when I first saw the demo, I thought it was a digital sidechain for sure. Well, wrong I was. They say it´s all analog and discreet, even sidechain and powersupply. There are great new ideas going on that thing. Impressive, I say!

Price?

Ruben Tilgner is the Inventor of the SPL Transient Designer.
He knows what he is doing with analog circuits :thumb:
and he is a nice guy, too

Very cool engineering (innovative parameters, temperature stabilization, et. al.) but I didn't care for it in practice. I can't say that I liked anything that was presented in the audio demo, including the plain vanilla compression. The one item that I would be interested in playing with would be the maximum gain reduction limit.

BTW, it should be pretty easy to add a negative ratio feature to the GSSL. My first build had that "feature" before I was aware of the 2150 to 2180 conversions.

-Chris

[quote author="rafafredd"]
Price?[/quote]

I think it's $5k USD MSRP

In Paris, another guy of that company, Dominik, gave me a demo of the compressor. I was impressed because they have features like a dry/wet mix function which is not so common (if not unknown) in analog compressors. I was furthermore impressed that these guys have the guts to develop one single product, which is in a high price segment BTW, and try to find their place on the market. In the first stage a kind of DIY approach too :wink:

[quote author="Emperor-TK"]BTW, it should be pretty easy to add a negative ratio feature to the GSSL. My first build had that "feature" before I was aware of the 2150 to 2180 conversions.

-Chris[/quote]

The dbx 903 has a negative ratio feature too. Also, Urei came out with a compressor that had a fully parametric EQ in the sidechain. I don't believe it sold very well though, or at least I never saw one outside of the showroom floor.

This compressor looks and sounds nice, although I'd like to hear it on something way less predictable than a drum machine...

I don't doubt that there is some pretty nifty design in there, but frankly I found that the drum sounded bloody awful after a while - find for synth tinglers!

That said - gimme the circuit!

The Barth Dynaset also has negative ratio on both the compressor & limiter !!

[quote author="Emperor-TK"]Very cool engineering (innovative parameters, temperature stabilization, et. al.) but I didn't care for it in practice.
-Chris[/quote]
I read the rave review in the latest TapeOp so got curious what was inside. I haven't seen or heard this box, but dunno how 'innovative' that temperature stabilization would be. I mean, it's a technique that's already out there and now happens to get declared relevant for a box like this (is it really ? it feels more like technicians delight).

Adding a mechanical gearbox to the controls for instance would then qualify as innovative as well :wink:

It'd be too easy to say that if a circuit needs this amount of temp-stabilisation then it's not the finest circuit to begin with, but OK, we're talking about the SPL-designer, who am I then ? But reading the full story gives a bit of a 'too much, too much' feeling.

Regards,

Peter

[quote author="[url]http://www.elysia.com/produkte/mpressor/technologie.html[/url]"]Thermal control of critical components
Some delicate circuit components can be influenced by the surrounding temperature easily. The main reason for this circumstance is the discrete transistors that can react very sensitively to variations in temperature (that can – depending on the place of installation and operating time – happen by all means).


With the T12 Heater elysia presents a system that arranges constant conditions and reduces the thermal fluctuation to a minimum. This system was inspired by high-precision measuring instruments. It features up to 12 discrete transistors in a massive copper ring that is warmed up to a definite temperature.


Once the system has reached its working temperature, it only needs little current to keep it at the same level. An electronic control circuit is responsible for a small variance of only a few degrees. The procedure is known from high end tube gear: the mpressor should be granted an adequate warm-up-time in order to experience it absolute top form.[/quote]

Man I want one of these so badly...I'll never afford one!
I agree that the blurb is a bit OTT, but the functions are great IMO.



So I have also wondered about adding similar features to a VCA comp.

The Elysia is a discrete VCA, feed-forwards with a sweepable tilit filter at the output. I think the G-SSL is mostly feedback - and after much thought I'm leaning to the Pico as it's also feedforward, so might be the ideal platform to modify?

The coolest features to me are the G.R limit control, the filter and the anti-log mode.

[quote author="Emperor-TK"]BTW, it should be pretty easy to add a negative ratio feature to the GSSL. My first build had that "feature" before I was aware of the 2150 to 2180 conversions.

-Chris[/quote]
I want to spend some time to figure out how to add something similar. Personally have been thinking about a discrete audio path, THAT VCA comp for while...with tilt filter at the output or switched into the SC - which the Elyisa can't do.

Anyone reckon it would be possible to add anti-log, negative ratios to the Pico or GSSL? It must be possible to add a limit function to the D.C sidechain feed.

The manual has plenty of nice AP plots to help.

-T

Interesting. But external isothermal operation, nice though it is, doesn't address signal-induced self-heating. For that you need clever design.