Some info: 1176 Compressor

The reputation of this analog classic is well known throughout the audio industry. Originally designed and built during the 1960's, the 1176LN was the first to use a field effect transistor (FET) as a voltage-controlled variable resistor, and that innovation was the key to the product's unique character. An in-depth analysis of the 1176LN's "personality" allowed Universal Audio to methodically reproduce those results within a plug-in architecture, and now offer that same character to computer-based audio workstations.   source: Sydec Audio Engineering  

Hardware Compressor Types And Characteristics

Tube (valve) compressors are more typically know as Vari-Mu. Unlike some designs, which simply have a valve in the circuit, a Vari-Mu compressor uses the valve for gain control.  As pointed out by Case (2007) a circuit is sent to a valve by the level detection unit to alter its gain, which results in compression of the audio signal. Vari-Mu compressors do not have a ratio control and increasing amounts of gain reduction are achieved with louder levels (Izhaki 2008). Due to the use of a valve for gain reduction, Vari-Mu compressors are not as fast as the transistor-based units. This can make them a suitable choice for drum busses and full mixes when preservation of transients is desirable. The classic Fairchild 660/670, Altec 436 and modern Manley Variable Mu are all examples of compressors that use valves for gain reduction.


Optical compressors (more commonly known as Opto) use a light and a light sensitive resistor to alter gain (Case 2007). A bulb, illuminated by the level detection circuit, shines on a photo-resistant material to control the amount of gain change. As noted by Izhaki (2008) despite the fact that light is used, Opto compressors are slow to respond to rapidly changing musical dynamics making them a poor choice if quick clamping on transients is required.  The classic UA LA-2A and modern Tube Tech CL-1B are examples of popular Opto compressors.


VCA Compressors are arguably the most common design. These compressors use a transistor based voltage-controlled amplifier. When using a VCA in a compressors circuit the control voltage is derived from the input signal and any gain reduction is related to this level. In simple terms, more level, more voltage more gain reduction. VCA compressors are considered to be the most transparent of the hardware-based designs. As Paul White states “In very general terms, a well-designed VCA compressor will provide the most transparent gain reduction, which is ideal for controlling levels without changing the character too much” (White 2003). Examples of VCA compressors include the dbx 160, the SSL console compressorsand the Neve Portico 5043.


FET Compressors use a Field Effect Transistor. Like the VCA, FET compressors can achieve very fast attack and release times. FET compressors also tend to colour the signal somewhat due to the FETs non-linear transfer function (White 2000). The 1176 and the Empirical Labs Distressor are both examples of FET compressors.  source : Jorunal on the art of Record Production 


Tube and Optical = slow working
VCA and FET = fast working 

 
To be aware of:

Dynamics processors are essential when recording, mixing and editing music. But when it comes to compressing an entire sum signal, a lot of digital compressors turn out to be unusable, many of them were made to process single-track signals only.
On complex sources they tend to produce a 'pumping' sound, distort or just make your music lifeless. There are manufacturers telling you 'this is the only compressor you'll ever need'. Don't believe them. Sound signals are far too complex to be handled by a single device.
Your music deserves care and attention to details. This applies especially to the post-mixdown stage, often referred to as 'mastering'.
source : Sydec Audio Engineering
 

Klanghelm DC1A  was the best compressor listed in above post's and what i keept
it colors ( add ) a little in the low end around 200 -400 hz so it's not completely transparent
but the compression style is good.
DC1A is free! So try it out for yourself. Klanghelm DC1A

Any other freeware suggestions ?

Eddie TX
The Audiocation AC1 is a decent 1176-ish freeware comp:
 
https://www.audiocation.de/en/plugin
 
Cheers,
Eddie
 

I know that is a good freeware compressor and want to use it , but i cant get it to
work in X2a it will not show up...

Edit : to get it work i must use JBridge, cause bitbridge cant handle it.

EDIT (Solved): worked in X1d 32 bit install

Opinions vary on quality but there is an attempt at what you seek here: antress.blogspot.com. these plugins caused a stir when they were introduced because the interfaces were blatantly modeled after well known classic gear. I tried them years ago but did no formal comparison. Free and worth try

I would like to thank clintmartin for this link:
 
http://www.tokyodawn.net/tdr-feedback-compressor-2/
 
This is a seriously excellent compressor and it is free to boot. I have used the SMART C2 hardware compressor a lot in the past. (don't own it but borrowed it though) It just does very nice things to a mix and it also makes the VU meters move in a certain way too after the C2 is applied to a mix.
 
I have been trying various software compressors to try and get as close to the C2 as I can with sometimes varying results from close to nothing like it. So far the mastering compressor in Harrison Mixbus has been very good. (Danny suggests the API 2500 and I am still keen to get it too)
 
But this compressor sounds very very good, very transparent and it makes the VU meters dance in a very similar way to the C2. Even when pushed very hard it does not sound like it is being pushed very hard and still maintains nice transparency. Excellent compressor. Highly recommended!!

Jeff Evans
I would like to thank clintmartin for this link:
 
http://www.tokyodawn.net/tdr-feedback-compressor-2/
 
This is a seriously excellent compressor and it is free to boot. I have used the SMART C2 hardware compressor a lot in the past. (don't own it but borrowed it though) It just does very nice things to a mix and it also makes the VU meters move in a certain way too after the C2 is applied to a mix.
 
I have been trying various software compressors to try and get as close to the C2 as I can with sometimes varying results from close to nothing like it. So far the mastering compressor in Harrison Mixbus has been very good. (Danny suggests the API 2500 and I am still keen to get it too)
 
But this compressor sounds very very good, very transparent and it makes the VU meters dance in a very similar way to the C2. Even when pushed very hard it does not sound like it is being pushed very hard and still maintains nice transparency. Excellent compressor. Highly recommended!!

Thank's a lot, this is indeed a decent compressor and will be in my collection.

I found out that i like the sound of FET compression like 1176 type emulations
to me they sound Fat and smooth in the compression behaviour.

dubdisciple
Opinions vary on quality but there is an attempt at what you seek here: antress.blogspot.com. these plugins caused a stir when they were introduced because the interfaces were blatantly modeled after well known classic gear. I tried them years ago but did no formal comparison. Free and worth try

Thanks, but i have already tried those, to be honest i am not quite sure about those compressors
have tried them many times but ended up deleting them again.. 
The antress " The lost Angel " and " Fire chainer ( 1176 type compressor ) " must be the better of them IMO.
I may have to test it one final time once more..    Antress

So far i use: Klanghelm DC1A and the TDR Feedback Compressor II
 

http://bedroomproducersblog.com/2012/02/18/bpb-freeware-studio-best-free-compressor-vstau-plugins/ 
This is a big list of free stuff. I don't recall ever seeing a 1176. If you have Sonar the PC76 in the Pro channel should do the trick.

Jeff Evans
I would like to thank clintmartin for this link:
 
http://www.tokyodawn.net/tdr-feedback-compressor-2/
 
This is a seriously excellent compressor and it is free to boot. I have used the SMART C2 hardware compressor a lot in the past. (don't own it but borrowed it though) It just does very nice things to a mix and it also makes the VU meters move in a certain way too after the C2 is applied to a mix.
 
I have been trying various software compressors to try and get as close to the C2 as I can with sometimes varying results from close to nothing like it. So far the mastering compressor in Harrison Mixbus has been very good. (Danny suggests the API 2500 and I am still keen to get it too)
 
But this compressor sounds very very good, very transparent and it makes the VU meters dance in a very similar way to the C2. Even when pushed very hard it does not sound like it is being pushed very hard and still maintains nice transparency. Excellent compressor. Highly recommended!!

Glad you liked it Jeff. Have you tried LimiterNo.6? http://vladgsound.wordpress.com/plugins/limiter6/
It has a good RMS limiter as the first module, but the Limiter is the best I've tried. I use it over Pro-L every time!

Cool those links are not unfamiliar with me, ill may also try the Molot Compressor again too.
think i have been trough most of the " known " free vst's on the market.
But i posted this just in case there was something i have missed out 

clintmartin
http://bedroomproducersblog.com/2012/02/18/bpb-freeware-studio-best-free-compressor-vstau-plugins/ 
This is a big list of free stuff. I don't recall ever seeing a 1176. If you have Sonar the PC76 in the Pro channel should do the trick.

I do not have Pro Channel, just my X1d studio, but i wish i had 

I will thank everyone that has been posting here, hope it may come
in handy for others too, that is working on a budget.