Small and large diaphragm Mic Differences - Continued

  • Thread starter Thread starter darnold
  • Start date Start date
What would explain the added depth in a U87 compared to a km184
 
night'schild said:
What would explain the added depth in a U87 compared to a km184
What is depth? Is it something you can define in objective terms, so I can know what you're talking about?
 
Well what I am thinking is that since sd's are more "directional" you lose alittle bit of the natural ambience a ld can pick up. Why would this happen?
 
Harvey Gerst said:
They answered the question and basically, it's a flaw in "dual diaphragm" condenser mics that lets them make that statement.

Yup, and the industry for the most part has been dealing with dual diaphragms so long that it didn't realize the new breed of singles were giving better LF response as long as the source distance (aka SPL) was tweaked to take advantage of the extra LF boost by removing the 2nd diaphragm.

I did find it interesting how the polar patterns change on the duals. Phase cancellations I assume can be attibuted to that. Lobing effects.

SoMm
 
Harvey Gerst said:
They answered the question and basically, it's a flaw in "dual diaphragm" condenser mics that lets them make that statement.

Below a certain frequency, the rear diaphragm adds enough resistance to the delay network to change the mic from a cardioid into an omni at very low frequencies.

Well, in fact, it is not as easy as they answer there. I re-read the article from Shure website. The difference in polar and frequency responses between single and dual diaphragms are proximity effect based, and depend very much on the distances from sound source, and the omni element in lowest frequency in dual diaphragms appears only at certain situations. In fact, at some distances, single diaphragm can have more proximity effect, as shown in article, contrary to what MG (and me above) have generally stated.
 
Last edited:
I went back and posted a long one...

Since my day job is a design engineer who has floated in and out of audio engineering for years I thought I could contribute to the large verses small issue.


SoMm
 
This is all very interesting. Its like we are getting into a little more advanced areas of mic design that is still a little unknown. Its awesome to see the design brainiacs discuss this stuff.

Night'schild - I think you are taking the comments and "stereotypes" a little too literal. Its not as simple as that. In general small diaphragms are little more directional but not always. It really has very little to do with diaphragm size, which is what we have been discussing here before. The factors of why a U87 sounds more in depth than a KM184 could have a million factors as to why. Could be because it picks up a little more of the room ambiences, it could be because the diaphragm is a different element, or the chips inside are different. But there are also going to be large diaphragms that sound less indepth and are less directional than the KM184s. Its different from mic to mic not based on the diaphragm size. How do you know that the KM184 is even more directional than the U87. You really dont know that, you are just assuming it because its a U87 is a large diaphragm and supposedly is less directional. So the factors of why a U87 would have more depth could be a million and not as simple as the fact that the U87 is a large diaphragm. Understand? In reality, even the fact that claiming the U87 has more depth than a KM184 is practically irrelevent to anything. On what source and for what reason?

Danny
 
Back
Top