Ohma Frequency Responses
Common Questions
What's a frequency response?
Frequency responses, also known as sensitivity responses, are one indicator that allows you to see some of the differences between microphones. They show the sensitivity of a microphone across the audible frequency spectrum.
Is the frequency response important?
The frequency response of a mic is a good starting point in understanding the general idea of a microphone, but it's only one indicator and cannot tell you what the actual tonality is.
Frequency responses do not take into account the differences in practical recording distance nor do they take into account proximity effect which occurs when recording from 2 to 10 inches away from the source- which is a typical distance used in modern recording.
At close distances, certain frequencies, specifically in the bass and midrange are affected in different ways.
Frequency responses also do not take into account how a microphone sounds off-axis from a source. Off-axis response is very important when recording instruments like drums and strings at a distance.
What's a big difference in frequencies?
When looking at a frequency response chart, a difference as much as 0.5dB can be significant in changing the sound of the mic- especially over the span of the entire frequency spectrum.
The overall shape of the frequency response might look similar between microphones, but those little dips and peaks can make a huge difference.
How did you do your testing?
Our testing was done at Harman Kardon US in their anechoic chambers at 1 meter away from the test speaker.
The microphones were measured with 50Hz to 20kHz sweep in a free field. This is the standard sensitivity test that Harmon does in this anechoic chamber to test microphones.
What's a good frequency response?
Many people believe that a flat frequency response is the best because it means your mic sounds transparent and therefore picks up sound in a natural way.
That's not true. Flat doesn't mean transparent. Flat just means that a microphone picks up an even amount of lows, mids, and highs at 1 meter. This response changes as you change your distance to the source. More importantly, flat doesn't necessarily mean your microphone sounds good.
Our favorite vintage microphones did not have flat frequency responses. They were all over the place. Sometimes the low end was bumped and sometimes the top end had a steep roll-off.
These attributes let us know certain aspects about microphones, but they don't tell the whole story. They're just ways to help interpret what a mic could be good for.
At the end of the day, putting a mic in front of a source and listening to it is the best way to know if it's the right mic to use.
Why does your ribbon mic roll-off the top end?
Ribbon microphones inherently roll-off the highs because they are a low-tuned system. This means that their resonant frequency is very low- lower than human hearing.
We tune our ribbon microphones to 20hz. Ribbons are linear above their resonant frequency. As you get higher into the frequency spectrum, they start to roll-off the top end.
By looking at a frequency response, you might think that it's a flaw in the microphones. But actually, this is something that makes ribbon microphones really special.
Ribbon microphones hear more like your ears. As you get older, your ears also roll-off the top end. One of our favorite ways to use a ribbon mic is to walk around a room while an instrument is playing. Wherever it sounds best, place your ribbon mic there. Often times, it sounds very similar to what you want the instrument to sound like.
Another benefit of a ribbon's high-frequency roll-off is that they can tame harsh sources. Instruments like cymbal and hi-hat bashers, distorted guitars, and strident vocals can all be smoothed out with a ribbon mic.
And if you feel like you need a bit more top end, you can always reach for a screen like Scales which boosts the top end starting around 6kHz.
Why does your condenser mic roll-off the top end?
Our condenser microphone is intentionally engineered with a gradual roll-off of high frequencies starting around 7.5kHz. This design choice stems from the inherent high resonant frequencies of condenser microphones, where a notable bump often accentuates frequencies in an unfavorable, harsh manner.
Our extensive development process of the Ohma condenser focused on achieving a seamlessly smooth top end tailored for various audio sources such as vocals, guitars, and drums.
The Ohma condenser incorporates a vintage Cinemag transformer which attenuates its top end while introducing harmonic saturation. These transformers contribute to a rich color and warmth in the sound.
We love our condenser's sound just like we love the distinctive tones of many of our favorite vintage condenser microphones. Most of these microphones had frequency responses that we consider wild. And yet they're still the go-to mic for many instruments.
What kind of smoothing did you use?
Most companies use 1/6th smoothing which makes their charts look significantly more smooth. It can be a bit misleading about the actual curve of the mics.
We chose to use 1/3rd smoothing so you can see as much detail as possible without the frequency response looking like noise.
What changes the sound of the microphone?
A microphone is electrical, acoustical, and mechanical. It is the sum of all three of these aspects working together.
The shape of the Ohma mic is a huge part of its sound. We've experiment with different body shapes, grille materials, fabrics, and grille shapes. Every aspect changes the mic's sound to some extent.
Using the interactive frequency chart: a guide.
Simply click on the screen icons below the chart to effortlessly show, hide, or overlay the curves of each screen type. It's a user-friendly approach to visualize and analyze how each screen compares to one another.
