[AcdNrg]

Hi to all!

So I´ve built my CP4500 a few weeks ago, was happy with the build process and am even happier with the results. Now there´s an appetite for more, hence this thread. My background is more in synths and modular, I´m not very experienced in the mixing and outboard processing world. That´s why choosing compressors is not the easiest for me and I´d like to ask the swarm intelligence a few things about the CP554. Apologies for referring to a second vendor, I´m trying to get the differences between the diode bridge compressors I find. 

0. What else is in my rack and what do I use that for?
dbx 560A
elysia mpressor 500
elysia xpressor 19"
100% electronic music, no mics, no vocals, no acoustic guitars. 80% material of the unts unts unts variety, techno, acid, sometimes house and the rest is soundscapes and ambient. Don´t look down on me for that, I played classic piano in my earlier life .

1. CP554 is a mono unit, so I´d need two for any bus application. That´s totally fine with me, as the ability to use it on two separate mono signals, probably earlier in the mixing process, is a welcome option. Money wise, 2x CP554 gets me close to the Heritage Successor, which brings stereo only -> it´s less flexible. However, there are some nice features like SC options and parallel compression. If only it was clear whether I´m looking for a channel or a bus compressor... but I mainly want to learn about bridge diode (BD) characteristics, try them out and apply them where they best fit. Thoughts about that?

2. There are some differences in timing and compression, and this leads to questions:
SS: Attack 0.5/1/2/4/8/16ms -- Release 100/400/800/1500ms/A1/A2 -- Compression 1.5/2/3/4/6/12:1
HA: Attack 0.05/0.2/0.5/2/5/20ms -- Release 25/50/100/400ms/A1/A2 -- Compression 1.5/2/3/4/6:1 + limiter


I wonder if these ranges lead to certain applications or types of signals. Probably not very black and white, more nuances (maybe big nuances), but I´m lost here. One can say that SS has benefits if longer release times are needed, whereas HA is super fast for attack and release. But I just can´t translate that into the use cases. Is it correct to say that the HA appears to be aimed at the master bus and that´s why they designed the timing in the way they did? And what does that say about the "best fit" for the CP554? Or is that maybe less related to the "where" of the signal chain, but more to the "what" as in "kind of material" (percussion heavy, transient rich, etc) or "how" the material is effected?

If I could, I´d just get both and experiment. But there aren´t any CP554 demo options and even if there were any: I already sold one of my kidneys for the eurorack modular . Reviews or demo videos are between rare and non-existent and most likely not for the genres I cover. And "just get both" isn´t the answer ^^. Same with plugins: the differences between those and their hardware counterparts are not exactly leading me to play with a DB compressor plugin to answer the questions above.

So maybe you can help me out?

[JPK]

1. What sets the Sound Skulptor CP554 appart from the other compressors you mention isn't really the diodes but the 3 Carnhill transformers in the signal path and the Neve output stage. It does give a richness to the sound which is not present on other compressors. In particular, if you try it on a drum bus, you will never remove it.

2. I don't believe there is so much difference in the attack times because these units all have the same origin. It is more a matter of how you measure the attack time: Is it when the signal gets to 100% or 90% or 70% (3dB) of the final level?

We plan making a demo video someday.

[AcdNrg]

Apologies for the late reply, but my day job was demanding these days .

After lengthy discussions, a good bit of research and fruitless reaching out to certain vendors, I decided that I´ll need to try and test and find out what actually fits my situation and taste in the best way. I need to start somewhere and decided to go with Sound Skulptor - mainly because of good experience with the CP4500, but also because no other vendor is even close in completeness, openness and transparency regarding the components in the box. Many companies try to get away with buzzwords sans detail and some seem to mislead you on purpose.

That said: Is there a strong reason to order 2x CP554 at once, just because I might want to run them as a stereo pair some day? Or is it possible to start with one, find out if the diode-bridge is something I like and then get a 2nd unit later on - without being concerned about matched pairs of parts etc.? How similar can those units be calibrated?

It may sound a little strange, but I´m still new here, trying to learn about the different characters and purposes.  So instead of getting a pair of CP554 to get familiar with a single type (diode bridge), I wonder if it makes sense to get 5176 + LA502 instead of the 2nd channel for now.  I don´t own any 1176/LA2A clones yet, just a few mid range dbx, bss, mindprint things plus the xpressor.

Comments welcome!

[JPK]

Thank you for the kind words!

You can start with one CP554 then add another one later, no problem.
The matching is done with the settings.
Any 2 units can be perfectly matched because the diodes have a very predictable behaviour.

I wonder if it makes sense to get 5176 + LA502 instead of the 2nd channel for now.
I think both approaches are valid. It's your own strategy.

[AcdNrg]

So I decided to go for a "compressor tasting session" and ordered CP5176, LA502 and CP554, let´s see which of these will get the "stereo upgrade" in the next weeks. I´m deeply concerned the answer will be "all of them", but that thought won´t spoil my soldering fun weekend I start right now. 

[JPK]

I can only approve!