Any one know the Focusrite mic pre topology?

[danielle]

[quote author="Samuel Groner"]BTW, if someone has nicely drawn info on the red or blue colored Foc-stuff, drop me a PM, please!

Samuel[/quote]

Hi Samuel,
Any luck yet?
Regards,
Daniel

 

[rich]

[quote author="SSLtech"]

Rich, I get the distinct impression from your postings that you're influenced more by what you think something should sound like rather than actually listening to it... I don't mean this as a criticism, but it sounds like your friend summed the original design up nicely: a transformer, a 5534 and a high gain stage (the transformer was omitted from his summary)

If it's simple, it might just sould like gold. That's how it frequently was for tubes, after all!

Keith[/quote]

And for the money that they charge you would think they were using something more than a 50 cent opamp, but maybe that's just all you need.

I also said this, " maybe that's all you need". That's what is fascinating to me about the preamp is that it sounds very good with out being overly complicated (no class A etc..). My point was really aimed more at the exorbitant cost of the Focusrite stuff considering it's a 5534 and two transformers. I really think a 5534 is a great neutral sounding opamp without being overly harsh sounding. One could probably make some very good sounding preamps with just a simple mic transformer and a 5534 opamp.

At the end of the day I just want it to sound good, doesn't matter if it's botique or whatever. At this point of the game the amount of money something costs doesn't influence me as far as audio goes. Visually though I'm still pretty influenced by those high priced babes.

 

[SSLtech]

Very fair.

However, those transformers are not cheap. The pumpkin is about $125 and the Lundahl is about $70 I'd guess... that very quickly jumps you into the $200 ballpark for a single channel DIY version, just to buy two of the components!

With that in mind, it's no wonder that every mic preamp came with a superbly engineered (though not entirely to my tastes a lot of the time) equaliser in the same package!

The 50-cent op-amp is the one precision part that's stamped out in the millions as opposed to being meticulously crafted like the iron bits were!

Keith

 

[rich]

I think it's the only preamp that uses an IC chip for gain that gets talked about as being in the same league as vintage Neve, Avalon, API etc... And even more remarkable is the fact that most people I hear go on and on about it have only used the Red series or even less expensive models. It makes me think a lot of people are hearing a name and reputation more than they are a mic preamp. I think I'm going to build several variations of the Focusrite and compare it to my botique stuff, I'll then feel like I'm part of the Myth Busters.

 

[rich]

ALSO IT WAS AROUND THE SAME TIME THE FOCUSRITE STUFF WAS FIRST COMMING OUT THAT PEOPLE WERE THROWING OUT THEIR NEVES API consoles etc... I remember my buddy picked up a blackface 1176 for $200 bucks from a well name studio. At that time the same studio had a awesome API console and a sweet Ampex 2" machine and they couldn't get rid of it. Everyone belived that Focusrite and SSL made their old gear worthless, that sure didn't last long. Not only is that funny, but it also prooves my point that a lot of times people's hearing is affected by the latest trend even professional engineers.

Also I'm not sure but I believe if you bought 2 channels of the Focusrite pre it only came with the pres. I don't think the red face had any output transformer, and 2 channels in a rack was 2k something. So you got 2 $50.oo input transformers and a few 50 cent opamps. I think the whole thing is poetic.

 

[Nickos]

Hi guys!
I'm still looking for the "pumpkin" transformer for the output.
Carnhill tell me that they can sell that part number only to Focusrite.

Do You have an idea of the caracteristics of that transformer so I can find a replacement? All I know now is that there is a tertiary winding and it's toroidal... any other details?

Thanks!

Nikos

 

[gyraf]

No further details yet, I think. We're still waiting for CJ to obtain a hacking-sample..

:razz:

 

[Nickos]

I can access some 110 module, but i think i can't extract too many informations...
If you tell me what i've to look at i can hack it
I can take some photo too....

Nickos

 

[gyraf]

I'm afraid it would need to be one of them "CJ Classic" hacksaw-jobs in order to extract the necessary information..

Jakob E.

 

[jensenmann]

CJ loves smashing Pumpkins :grin:

 

[Nickos]

There is nothing I can do about it?
I can try to test the transformer in several way...

I only need to know how...



Thanks,
Nickos

 

[CJ]

It's almost October.
I better have one of dem pupkins, or uber else.

 

[Svart]

yes someone get CJ one of those trafos please.

 

[justinheronmusic]

I'm resurrecting this thread. Did anyone ever find the specs on the pumpkin? As far as the Red 1 schematic, I saw one posted but these tired eyes can barely make out the resister values. Anyone have an updated scheme?

I am potentially interested in designing a two channel board for the Red 1.

 

[thomasdf]

For some reason I had missed this thread, lost of great info, which may be used in this project : https://groupdiy.com/threads/rouge-un-my-attempt-at-a-red-lundahl-5534-preamp.88241/