Originally Posted by brianroth
The AM-16's were somewhat "typical" of the time that they were made. They have a fixed 45 dB of gain.
Is that enough? Too much?
"Enough" gain would depend upon whether or not you are recording a flute at 50' away with a ribbon mic.
"Too Much" gain could be a problem with a high output mic closely located to a Marshall stack with the volume contol at "11".
The second situation I mentioned is easy to correct, though. It's called PADDING, although you have to be careful how the pads are designed so the tonality isn't seriously compromised.
Later preamp designs, such as the API opamps, allowed a change of gain of the amplifier stage, but that is not without problems, either.
OTOH, the Langevin amps were intentionally designed to operate at a fixed gain, and various "kludges" to vary the gain that I've encountered are just that..a kludge!
To properly use something such as the Langevins, you need to use them as intended (and NOT as some folks have tried to mod them as "variable gain")...with input and/or out pads.
Just to give everyone an idea of what Brian is talking about
: My previous racking job of the Langevin AM-16's was done by a well known tech in Southern California. He blew all sorts of smoke up my rectal cavity about his skills. When I got the units back not only did they look like total crap they never actually seemed to work as well as they should. They sounded good but they never had enough gain for most things except maybe drums. After spending a number of years with them only working off and on and also that tech not returning any calls or emails I had pretty much shelved them as unreliable. Last year I decided that it was time to get them re racked and found Brian through Gearslutz and PSW. When I sent them to him he mentioned that they were wired wrong. The impedance was wrong, and the pad structure was wrong. We talked about how to properly pad the inputs and outputs and he went to work.
When he returned the units to me they looked great, Were racked really strong and bullet proof, and sounded amazing. Much more open, clear, and robust than I had ever heard them before. The other amazing thing is they had more gain than I ever would have thought. I rarely ever run them wide open now. With todays hot output mic's the gain is usually more than sufficient.
In my research I have seen a number of ways that guys are racking these and most of the time it is wrong. With these modules it will really affect the functionality of the pre's.
FWIW, The only people I have found who rack them correctly are Brian Roth, Helsing Audio, and JLM in Australia. All these guys do incredible work and are very reasonable on price. There are some who charge quite a bit more and do ok work but I have never felt that confident about when talking to them.