Current Mic and Preamp Project

[StupendousChumley]

Greetings,
As a newbie to the group, thanks for having me. My current mic project revolves around the ORS inspired U87i stripped down circuit.

I got a PCB board from Hula Cow designed for a TLM103 body. My other build is a Jensen Twin-Servo preamp design, the J99 from Seventh Circle Audio.

QUESTION: Is there potential for attaining more preamp 'coloration' by engaging a -10db mic pad (for voice/acoustic) and driving the preamp more?

 

[kags]

I find the Jensen Twin servo and John Hardy preamps don't really saturate until they really break up - that's kind of the magic of those preamps - solid tone throughout the useable range. I love the Hardy M-1 on most everything and I use them a lot. I have only used a Boulder Twin Servo a few times—and for those recordings, the singers were so good nothing else mattered!

A pad might change the tone and/or noise floor in a noticeable way, but I doubt the preamp will provide more color either way.

I am interested in how the J99 turns out. I've used the Seventh Circle N72 and that one sounds very good.

 

[StupendousChumley]

Thank you kags, I'll share an update shortly when I complete it. I just got an Audient ID24 interface to use in conjunction with it as well, so I could bypass the internal preamps of the interface using the return insert they added.

 

[ruffrecords]

The Jensen preamp uses a lot of negative feedback which significantly reduces distortion (tone). If you place a 10dB pad before it then you will need to increase its gain to maintain the same output level. This is achieved by using less negative feedback which means its distortion will rise but I suspect the amount of increase will be so small as to be inaudible.

In addition, the distortion in almost every preamp is directly proportional to its output level. So, if you were to place a 10dB pad after the preamp you would need to raise its output by 10dB to maintain the same level which will increase its distortion by the same amount. However, the amount of distortion produced is probably so small as to be inaudible.

Cheers

Ian

 

[kags]

I agree with Ian and the Twin Servo is known for its solid tone at almost every gain level until it just blows up. In other words, it’s neutral until it’s unusable. I find the same with my Hardy M1s, in contrast to API or Neve that offer degrees of useable saturation.

That’s why producers chose the twin servo for vocalists like Celine Dion and Whitney, who could go from a whisper to a roar and the preamp handles it all.