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Old 23rd September 2013 | Show parent
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Originally Posted by Deleted 2ef94c53 ➡️
I have also discovered what SoSueMe said regarding multing mic signals between two preamps. The sound changes compared to a direct connection, and it usually affects one pre more so than the other. I agree that it must be an impedance issues that affects the high end in particular.
As far as I understand the impedance mismatch happens when you simply split the signal, for example with the help of a half-normalled patchbay. The impedance is then divided by the number of receiving devices. Each device might react differently to an impedance that is too low (for example, when people complain about "the frequency anomalies of the ADL 1500 coDeleted 2ef94c5essor", they feed it with an inappropriate impedance. The mid frequencies then sag the more the unit coDeleted 2ef94c5esses. With proper impedance matching it is a wonderful unit, and shows none of that behavior). What you will find out in such a test is how the unit reacts to impedance mismatch, and not how it sounds.

When you use splitters with transformers you isolate the circuits. The mic and the primary coil of the transformer form a closed circuit together, and each unit forms a closed circuit with their corresponding secondary coil. What the inputs of the units "see" then is the impedance of the secondary coil. So there is no impedance mismatch.
Still, they represent loads to each other (or whatever the correct word is - they are electromagnetically coupled), and that can affect their sound. And furthermore the transformer will add its sound.

I hope this is understandable - English is not my main language. And it might all be incorrect anyway. I hope someone with real knowledge in electricity will correct me if I'm wrong, or add data.

When someone explained to me that an amplifier doesn't amplify a signal, but makes a (more or less exact) copy of it with higher amplitude, I had the iDeleted 2ef94c5ession that I understand a little more about it all. There is no signal flowing through a unit. It's more like closed circuits that interact and affect each other.

Originally Posted by Deleted 2ef94c53 ➡️
Rumi, I am very sorry to hear about your burglary, where 21 mics were stolen. That is my worst nightmare. I am glad to see you rebounding so well and that your engineering spirit is obviously still intact.
Thank you very much!
It was an intense time, with a lot of changes. The mics were so easily accessible because I had stacked them all to test them, to see which ones I will keep. I sold about 2/3 of my studio equipment during that time, and went on long retreats.
Some of the mics stolen were one of a kind.
Thank God they didn't take the Wagner, and also some other mics.
That burglary was part of a much bigger transition, and the outcome of that transition is very wonderful. I also experienced so much support from the audio community! It was heart-warming.
I moved into a new studio in March, and it's thriving! I enjoy working with sound very much.

Originally Posted by Deleted 2ef94c53 ➡️
My suggested test (to be done in addition to the others) is to use your 3 CAD 350s as best you can. First confirm that their frequency responses are as close as possible using the same pre on each each mic, but across 3 performances. Then after confirming that the 3 CADs are 'matched' close enough for testing purposes, line up all three capsules as close as possible (pick an axis for all of them to share according to the instruments dispersion) and record a single instrument performance (solo acoustic guitar would be nice) with three different pres (and three 350s). You could even swap the pres and mics around for a second or third take to ensure the positioning and mic differences arent throwing off the test. Again, this would be just one test along the road...
Yes, I will do it that way. And I am a professional guitarist, so there will definitely be some guitar.

May I ask why you suggest the CADs, and not the Grosser-modified Gefells? The CADs are big, it might be hard to get them close enough to each other. Apart from that, they are great mics. Since I suggested them to so many people, I could organize at least six of them. But that would make quite an array, far from coincidence recording.
I will send the Gefells to Andreas Grosser this week. I bought them from someone else, but Andreas told me that I have to send them to him, and he will upgrade them for free, because he has found a better FET for them since. Andreas is such a nice being! Very commited to his work. And I will look for more Thiersch'd M70.

Originally Posted by Deleted 2ef94c53 ➡️
Your list of pres is the most iDeleted 2ef94c5essive gathering I have ever seen on GS or in any studio. Looking forward to your results. Don't forget to have fun!
Thank you, I wasn't aware of that! They have just come together over time...
But when I listened to the Lynn Fuston preamps DVD I realized that most of the ones I liked I own. There's still the Gordon, though... And I also liked Great River and Lipinski in that test.

And yes, I won't forget to have fun!

Thank you for your kind words.