Shure KSM8 Dualdyne Review

The US manufacturer of professional microphones Shure has over 90 years of experience in the audio industry. And just to think that initially they sold radio parts kits. Only later, from 1931 onwards, did the company start the construction of microphones, which would go on to mark milestones in the history of microphones for live and studio applications. In fact, in 1939 Shure introduced the Model 55 Unidyne, which would become one of the best known microphones in the world. Twenty years later, the Unidyne III marked another important stage, being the predecessor of the beloved SM57, introduced in 1965, together with the legendary SM58, just the two best selling microphones in the world!

Shure KSM8 Dualdyne

When Shure announced that it would present a new handheld microphone at the NAMM Show 2016, all the experts pricked up their ears. But no one ever would have expected a dual-diaphragm dynamic microphone! With the new KSM8 Dualdyne the Shure engineers have worked to bring the technology and performance of dynamic microphones to a new and innovative level, and in this review we will discover if they succeeded.

Shure KSM8 Dualdyne_gear2

First impression
Removing the KSM8 from his stylish pouch supplied, it immediately presents itself as a professional microphone with excellent craftsmanship and superior quality components. The die-cast aluminum body with black finish (or brushed nickel) and hardened steel grille give a feeling of great sturdyness. Unscrewing the grille lets you discover that the inside is lined with hydrophobic woven fabric, and only on the flat side of the tip there is the classic foam. On the sides instead is a particular synthetic material which in the upper part of the grille is flat but always slightly spongy, and in the lower part instead is very fine and smooth, with a perforated dense texture, to protect a dual-diaphragm capsule that in my opinion is spectacular in terms of appearance! Let’s discover what hides inside.

KSM8_Dualdyne cartridge side view

The Shure Dualdyne cartridge
The characteristics and construction of the Dualdyne capsule are really interesting! It uses two thin membranes (the front one is active and the other passive) and a reversed side entry airflow system. What does it mean? Sound enters the microphone via the side entry inlets and passes through the rear second diaphragm before striking the front diaphragm. By using the second diaphragm in the resistance network low frequencies are partially blocked from entering the cartridge resulting in a natural, low-end response with controlled proximity effect and no loss in clarity.

Proximity effect
We all know the effect of proximity, i.e. an increased low frequency response as the performer moves closer to the microphone. To counterbalance this effect, in conventional microphones the range around 4-5 kHz is often emphasized. The idea which is at the basis of the dual-diaphragm technology is instead to generate a natural response in the lower limit of the band, with a controlled proximity effect and no loss of clarity, and with wide response to high frequencies, eliminating the need for a strong presence peak.

capsula Dualdyne airflow

To make the optimum use of a traditional microphone, you are forced to stay with your mouth at a precise distance from the microphone, in order not to run into tonal variations. The balanced response of the dual-diaphragm microphone instead creates a bigger “sweet spot” and allows the performer to move more freely without affecting the sound quality.

Live sound engineers are often forced to use a heavy signal processing, like equalization, to mitigate both the proximity effect of traditional microphones or to compensate for improper microphone technique. The double diaphragm provides a broad response to the vocal range and is less sensitive to incorrect use of the microphone, with the result of having to make less signal corrections, thus obtaining a more natural sound.

The dual-diaphragm microphone delivers a smoother response throughout the vocal range and is less susceptible to improper microphone handling, requiring less corrective signal processing and resulting in a more natural sound.

Shure KSM8_esploso_nero_horizontale

Off-axis Linearity
When unwanted off-axis sources leak into vocal microphones, it can degrade phase coherence and compromise source quality. The KSM8 provides greater immunity to these problems, due to linear polar response across the entire frequency spectrum.

The Diaphragm Stabilization System (DSS™) works with the pumping pneumatic shock-mount to isolate and suspend the cartridge, reducing handling noise. In addition to diminishing unwanted movement, the moving piston and internal cavities have been precisely engineered to stabilise the diaphragm amidst mechanical vibration.

In trial
I tested the Shure KSM8 Dualdyne for two weeks, subjecting it to various tests in both live and studio environments.

First I connected the KSM8 to my sound card, performing a series of listening tests, on reference monitors, various headphones, PA systems and also with floor monitors.

Generally the mic reproduces the voice in a very balanced and natural way, with a warm and present sound. The signal is clear and detailed, but without emphasising a certain frequency range as we are used to in other microphones.

Listen to this file, a vocal arrangement of an old song of mine, recorded with the KSM8 Dualdyne, entering directly into a RME Fireface 800 interface. The vocal tracks that you hear are flat, that is nothing eq and no compression.


Well, let’s check out the various features as stated by the manufacturer:

The output level is higher than all other dynamic microphones I have in the studio.

Indeed, the proximity effect is much better controlled. There is low end, but less “muddy” than in the other microphones.

But the truly amazing thing is the great overall tone when you move the microphone away from the mouth. Even at a distance of 25/30 cm, and in contrast to the loss of volume from other dynamic microphones being heavily noticeable, the sound reproduced by the KSM8 remains full and balanced. Even moving a little off-axis, the microphone can reproduce the source much more faithfully than other handheld microphones I know of.


To understand better, I compared the KSM8 with four other dynamic vocal microphones. In the following audio files you can listen to some voice samples recorded at three different distances (with the mouth attached to the grid / 10cm / 20cm). Find in sequence: 1. Shure SM58, Shure Beta58 2., 3. Sennheiser E855, Telefunken M80 4. and 5. Shure KSM8 Dualdyne. I  digitally standardised the recordings’ gain levels to be able to better demonstrate the timbre changes rather than volume.

Since I found on the internet the criticisms for a supposed problem on plosive sounds, I also added a file with examples using words with “p”. Judge for yourself.

The better performance on distance and off-axis could perhaps lead one to think that the KSM8 is more sensitive to feedback, but it is not. In addition to live shows with my power trio, where I was really happy with the microphone, I also tried the Dualdyne on my singing students, with different types of voices and “rock’n ‘ roll” monitor volumes. Even with no eq on the mic the sound that is coming out of the monitor is really nice, just the way it is, and the risk of feedback is very low.

Dualdyne @ Blue Note
In order to evaluate the KSM8 in action even as a listener off the stage, and to get an opinion from a great professional in the field, I involved Zoran Matejevic in the testing, resident engineer at the Blue Note in Milan, Italy. Matejvic proved to be very interested as soon as I had spoken about the test on He used the KSM8 for five days on British singer and saxophonist Ray Gelato, who inflamed the Blue Note with his Giants, with nine shows full of swing, rhythm and blues and jive. A stage not easy to manage acoustically, with grand piano, bass, drums and brass section (trumpet, trombone and tenor sax) and important monitor volumes.

Here is the testimony of Zoran Matejevic: “Shure says that with KSM8 the proximity effect is very controlled – it is true. But that’s not the only strong point of this microphone. Excessive dynamics in pronunciation or singing do not change the tone, making the management much easier. Both for monitor as PA I needed to apply very minimal eq corrections, lowering the 5th oktave about 1dB /1.5 dB, specifically from F#5 to C6 [the range from 740Hz to 1046Hz, ed]. I just added a high pass filter and the game was done. Awesome.
On a stage with high and challenging sound levels, the microphone gave me the feeling that the voice does not dominate with the volume or with the range of 1.6kHz but with the fundamentals. You never lose the lead and you have the feeling, as if the channel was super processed, a sound straight in the face. The intelligibility on the consonants, from dental to the hissing, finally allows you to concentrate on the music and voice. No disapprovals on nasals and plosives, under-stressing that sibilance and fricatives are very natural.
Everything is easier in the mix, the voice always comes out, without the need to constantly have your finger on the fader of the lead voice. This feature, which I like to call the ‘Pultec’ effect, allows you to work comfortably with the sound.  It’s important not only for the management on stage or the PA, but also because I am convinced that with its characteristics the KSM8 will be also very indicated for broadcast and streaming.
Two criticisms: I didn’t find the anti-shock system so effective, in fact that could create problems if the singer claps his hands with the microphone or abruptly puts the microphone into the stand clip, as Ray Gelato does continually. The supplied clip is one of the classic Shure clips, that forces you to apply pressure remove and insert the microphone. Maybe I would have preferred a soft clip that would allow you to fix the microphone with pressure from above. Apart from that,  I liked the KSM8 very much. Congratulations to Shure. “

As a listener of the Ray Gelato Giants concert I can only confirm what Zoran Matejevic said: The voice was always there, with a very balanced sound, even if the artist is certainly not one of those who stays in a fixed position or a constant distance from the microphone, but instead is continuously taking the mic from the stand, singing, passing the microphone from hand to hand, moving away and moving closer to the microphone, inserting the mic in the clip, making a sax solo, taking the mic again from the stand, having a dance, and so on. On stage he had two monitors, 400 watts each, with stratospheric volumes (you could hear these up to the FOH position), and there wasn’t one case of feedback.

Well, what to say … Shure has actually created something new, a new breed of microphone that has not yet been seen. Inserting a dual-diaphragm into a dynamic capsule with cardioid characteristic actually turned out to be a genius idea!

Final evaluation
The excellent craftsmanship, the increased level of output, reduced proximity effect, the increased working distance, and a clear and very detailed signal with minimal feedback, make the Shure KSM8 Dualdyne a professional high-level handheld voice microphone, even in the most demanding live environments. Unfortunately the price is high-level too: 500 dollars is not cheap, but I’ve convinced myself that it makes sense for a microphone of this quality.
SHURE_KSM_3Also, not to forget, that in addition to the versions in black or brushed nickel finish the KSM8 may also be purchased as part of a Shure wireless system, or as an upgrade to an existing wireless handheld transmitter.

Shure has also made a number of interesting video presentations and technical explanations, and they can be found at the following links:

Shure KSM8: Inside Dualdyne
Shure KSM8: Unidyne to Dualdyne


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