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[Stu Gutz]

Quote:

...Klaus, Can I ask why you choose to edit my posts?

I guess you prefer your original post to the .... Klaus Heyne Edition?

[Barry Hufker]

Testing microphone frequency response:

You would have to do it in a manner similar to the method used in anechoic chambers.  But without the chamber, you will have to go outside, some place *extremely* quiet.  Put the speaker on a stand.  Raise it well off the ground to minimize ground reflections.  Put the microphone on a stand, placing it so it receives both tweeter and woofer very well.  Place it 1 meter away from the speaker.

Play a 1kHz tone, using this for calibrating output level of speaker, microphone and preamp.  With a sound pressure level meter, measure the speaker's SPL output.  Jot this down as it is now your reference.  Each time you play a new tone, don't measure the microphone's output until you guarantee it is the same SPL as the 1kHz tone.  Do this until you're sick of it or until you have the response.

This test assumes the preamp is totally linear.

Barry

[ssltech]

Barry, swivel your thinking around 90

[Barry Hufker]

Thanks for the better method, Keith.  It sounds "right" to me!

Barry

[Brian Kehew]

>>This test assumes the preamp is totally linear.<<<

I bet ya the mic pre is more linear than the speaker!

[Barry Hufker]

Yes, you're right!  That's why you have to keep measuring the SPL to make sure the speaker is playing each tone at the same level as 1kHz.

Barry

[Extreme Mixing]

Agreed.  It doesn't seem possible to get reasonable results at home.  I live in LA, so there will never be a quiet enough time, even at night.  I don't want to dig a hole, and by the way, it's been around 20 degrees at night!!!

I think I can come up with a comparative test that may be useful, using another mic with a published frequency response and  pink noise.  It's not really important, I suppose, if one goes with the "if it sounds good, it is good" mantra.

Thanks for the info.

Steve

[Barry Hufker]

Making the test indoors is problematic because of the standing waves.

It *might* be that there is somewhere in LA an anechoic chamber you might be able to use if someone takes an interest in the project... From what I understand, even Neumann has to extrapolate microphone response below 50 Hz because of the size of their chamber.

Barry

[Kris]

Extreme Mixing wrote on Tue, 09 January 2007 19:07

I took the mic back to Dave, and he changed out a bunch of stuff.  The mic is much fuller sounding now.  It's a pretty dramatic difference.  I'm going to use it for the next couple of days and see how it goes.  You know, like a guitar player with a new wah wah pedal. Steve

How many other mic manufacturers would do something like this?  I had a similar experience with Dave... Tried one version of his mic... didn't like something about the high end... he was HAPPY for me to sent it back... he followed up with another mic, which was PERFECT... a class act all the way!

[J.J. Blair]

Kris wrote on Mon, 29 January 2007 07:37

... a class act all the way!

100% agreed.

[Extreme Mixing]

Yes, Dave has treated me very well through the whole process.  I'm using the microphone, and I may make a couple more small changes, but all in all, it's worked out good for me.

On a lark, I ordered a couple of the Shiny Box ribbon mics.  I should get them in a couple of days.  I ordered one each of the Cinemag, and Lundahl transformers, with the intent of trading one to wind up with a matched pair.  Looking forward to hearing them too.

Steve