Ultra High Gain Mic Preamp

[JohnRoberts]

While the hype merchants would have us believe otherwise, premium mic preamps have been approaching theoretical noise performance for decades, while there is some noise performance differences at less than full gain, for your application, the room and mic should dominate the noise floor.  As an old mic preamp designer I'd love to argue otherwise, but spend you money on a good mic.

JR

 

[okgb]

We're not talking about gain staging but how much noise the actual mic generates based on
the load it's connected to ? as being the main factor ?

 

[nielsk]

JH M1 has TONS of gain, very low noise...

 

[gridcurrent]

While the hype merchants would have us believe otherwise, premium mic preamps have been approaching theoretical noise performance for decades

JR

So true.
A Langevin 116, circa 1947, can yield an equivalent input noise figure of -129 dBm; similar numbers from an Altec 1567a.

 

[BYacey]

Refrigerated preamp rack!

No, refrigerated mic/recording room!

The secret for quiet recordings is in the microphone and the room, not the preamp. Get a decent modern large-diagrphragm, transformerless condenser mic (just a random choice from my own list: Microtech-Gefell M930). These types have the lowest currently possible noise figure (around 7 dB-A) such that the background noise of most recording spaces will dominate and so high sensitivity that the preamp will not matter anymore.

If you insist on a different particular mic type (dynamic, ribbon, old condenser) for sonic reasons, you'll have to accept a compromise.

Samuel

That's all we need is to be unsticking some singers lips from the windscreen.

I still like the Valley circuit. It's so quiet you can hear the noise floor from a condenser mics preamp stage (AKG 414 BULS), in my tests. It really shines when using a dynamic mic.

 

[JohnRoberts]

That's all we need is to be unsticking some singers lips from the windscreen.

I still like the Valley circuit. It's so quiet you can hear the noise floor from a condenser mics preamp stage (AKG 414 BULS), in my tests. It really shines when using a dynamic mic.

I ASSume you are talking about the transamp? Paul Buff wrote a great article back in dec 1977 RE/P magazine about the importance of bandwidth in noise measurements and common mistakes when trying to compare dissimilar measurements related to termination impedance etc..

yup Paul had it figured out some time ago... So much of the claimed improvements since then is marketing fluff, while I do appreciate that now we can buy ICs that compete with old discrete designs.

JR

 

[[silent:arts]]

talking about transamp ...

http://www.schoeps.de/en/products/vsr5

 

[CJ]

lo noise hi gain is fun for listening to the outdoors at night, put a condenser out there and jack up the gain, you can hear all kinds of stuff, maybe sample a 57 buick going down the road,if you use a break before make rotary on the v76, you can wedge it in between clicks to get open loop gain, which is higher than any preamp out there, but lots of noise at this level,