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The Equinox Q47 D Capsule

Review by Fox Audio Research

Q47 capsule in the case

Its always fun to get a new capsule and we got one into the shop that we have never tried before. The Equinox Q47-D came in via a customer, Graeme Spicer, who is a voice over artist. He had asked me to try and make a u47 sounding microphone for him and he had gone ahead and purchased his own capsule from the good people at Equinox.

We were both knocked out with the classy packaging. Graeme has an impressive history in the professional marketing world both on the agency and the client side of things, so when he's impressed it means something.

The published response was in the case as you an see in the photo which I always like and after it was installed it looked pretty similar when I measured it. You have consider that I don't have an anechoic chamber so my plots always look a little different that ones done in more accurate conditions, but it always makes me feel good to see I am in the ball park.

So Graeme Spicer, brought in a nice micrphone to put his new capsule in and it was the Advanced Audio CM-47. It's a very nice mic it's own right, with a nice big transformer tucked inside and an AK-67 capsule that is sourced by Advanced Audio. It looks and responds very much like the Peluso CEK47 capsule. It has tons of high end and a very flat, even response on the bottom. There is also a nice little lift in the mids and the anti-sibilance notch at 7..8 KHz. All in all a very nice mic for the money.

So when we put the CM-47 up in the shop the response looked like this with the stock capsule and electronics

CM47 cardiod response graph

Nothing to complain about at all. But Graeme was looking for a slightly more vintage sound. He uses a u87ai with the "Inner Tube (tm)" electronics and provides him with a nice bright sound. This is because the "Inner Tube" circuitry does not use "de-emphasis" to correct for the high end lift in the u87 capsule. So already he had a mic that gave him "bright". He wanted another mic to give him "warmth".

We did some examination of the CM47 electronics and found that it was adding some high end lift above 10KHz so we made some changes that flattened it out to better match a u47 preamp response. With the CCDA, two triode circuit that Dave Thomas uses, it was easy to achieve. (Dave and I both like that circuit)

We also replaced the bias resistor with our diode bias option. This increased the gain of the preamp by 4 dB and seems to add a bit of punch to the sound. Not totally necessary but I like it. I also did something to the output cap that gives a bit of that u47 low end woolliness to men's voices. Announcers love it.

Now the CM-47 chassis puts the capsule pretty high up into the cage and when we measured the Equinox pedestal it was going to go up even higher. I was not comfortable having the cross bar of the head basket crossing the capsule that low on the capsule so we elected not to use it.

The Equinox pedestal is a very nice innovative design, it just wasn't right for this mic particular chassis.

Q47 capsule and pedestal

So we put in the Q47-D capsule and put everything back together and it sounded pretty damned nice! Good mid-range pop so you know you are talking into a u47 type mic. And the highs roll off smoothly so the de-esser can stay in the closet most of the time.

Below is the final response and just for the record we compared it to a Peluso Capsule in the same kind of TCM1050 headbasket.

Q47 capsule cardiod response graph

CM47 with Peluso K47 capsule response graph

You can see the Peluso is flatter on the bottom and it has less mid-range lift, but they are definitely both K47 style capsules.

So how does it sound. Well here is Graeme Spicer using his modified CM-47. The recording is using a tube preamp with no compression or EQ. It is a .wav file so it's pretty big. About 5.5 Mb


Graeme Spicer on the CM-47 modified, with the Q47-D


So check them out.

I have only good things to say about the Equinox Q47-D.

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