4301 datasheet compressor?

[jmejia]

Has anyone built the compressor in THAT's datasheet for this guy?

I'm totally new to analog electronics - and really don't know what I'm doing - but I'm laying out a little pcb based on the schematic - should I expect a decent useable compressor from it?

<edit to add link> http://www.thatcorp.com/datashts/4301data.pdf

fig. 14 is what I'm looking at.

 

[emrr]

I believe there are multiple variations and additions within their data sheets, and definitely many viable products on the market based on yet more variation.  I don't remember seeing an account of anyone building the exact sample circuit(s) and reporting in depth.  Perhaps this is for you to tackle?   

 

[JohnRoberts]

THAT corp is about the last VCA maker left standing, so I suspect there are many compressors out there using that chip set, or their earlier versions.

Perhaps review all of their applications notes, and even do some research into old DBX corp AES papers covering sundry aspects of dynamics design.

That chip set is the guts for many a DIY processor, but there is room to experiment with the details, depending on what you want to end up with.

JR

 

[PRR]

> should I expect a decent useable compressor from it?

Yes.... but...

It is unbalanced in and out. And the output is rated for 2K minimum load. When you get in a studio with "pro" pretentions, they whine about stuff that isn't "Balanced". And may sneer at anything that can't drive 600 ohms. This is "simple building-block" stuff, you can buy the interfaces as one-chip implementations.

It has no meter, not even a blinky-light. I can't use a limiter that way; anyhow meters/LEDs look cool.

THAT has a lot of stuff on their site, read it all and more.

If you just "need a limiter", you can buy fine boxes (often based on THAT chips/notes) for $100-$300 at Banjo World and other fine rock-shops. I got some $129 thing and had no complaint using it as a safety limiter (to tame the unexpected 6dB-over peak). If you need "a certain flavor" of limiting, you can spend a lifetime testing various models and samples.

Since tape faded, I recorded "without limiting", the limiter in-line only to cover my mis-guess about a piece's level. Most live performances must be squooshed to play-back well in typical listening spaces.... I did that on the PC, with an un-do function.

 

[strangeandbouncy]

Hi,


  I would just like to point out that here in our very professional studio, we actually don't have a single piece of gear with a 600ohm input! Everything is 10k on line ins. I don't know of a converter or interface that isn't 10k(anyone?), so something that'll only drive 2kohms would be fine here at least! And we don't do whining, just wining - ahem.


    kindest regards,


        ANdyP

 

[Biasrocks]

<edit to add link> http://www.thatcorp.com/datashts/4301data.pdf

fig. 14 is what I'm looking at.

You're probably better off building THAT's demo circuit, detailed here.

http://www.thatcorp.com/datashts/4301demo.pdf

You could add THAT's 1646 line driver (http://www.thatcorp.com/datashts/1600data.pdf) to the circuit for a balanced output.

Mark