Apex 460 Mods
The Apex 460 is one of the best mod platforms on the market. We have multiple mod options for this mic, both sonic and cosmetic.
#1: Capsule Replacement
The 460's capsule is a common 32mm K67 type, found in nearly every inexpensive large-diaphragm condenser ever made. It is not a great-sounding capsule, due to its uncorrected high-frequency peak. And it's the wrong capsule for this circuit, in any case.
Our favorite (and best-selling) capsule for 460 mods is the RK-12, which is our version of the capsule in the famous C12 and ElaM 251. The RK-47 is another perfectly viable choice, if you're going for a U47 vibe.
See all of our large-diaphragm microphone capsules.
#2: Grille / Headbasket Replacement
Our C12-style grille for the Apex 460 provides an easy cosmetic upgrade.
#3: Circuit Replacement
We make two distinct circuit replacements for the Apex 460. Both offer user-controllable high-frequency EQ, so that you can adjust the mic's high frequency response at build time. Both circuit kits include custom circuit boards, best-in-class components, and US-made output transformers.
The Fox 460 circuit kit is a dual-triode cathode follower design; it uses the second triode of the included 6072 tube to reduce impedance before the audio signal hits the transformer. This topology allows the use of a lower-ratio transformer than the original mic used, which in turn gives the modified mic higher output. The transformer is a custom-wound 6.5:1 ratio. Click the image at right to see many 5-star reviews for this circuit. See also the reviews of the 12-251 microphone kit, which uses the Fox 460 circuit. (If you don't already own an Apex 460 to modify, you could skip the step of sourcing a beat-up 460 on Ebay and purchase the 12-251 instead.)
The new V-251 circuit kit is a single-stage triode design, more closely modeled on the original Telefunken ElaM 251. It uses a T/14 transformer (11.5:1 ratio). It has approximately 6dB lower output than the Fox 460 circuit, but 6dB more headroom. This circuit kit also offers an internal high-pass filter switch, and your choice of HPF behavior (rumble filter vs. high pass); two different HPF components are included, enabling you to choose which you prefer.
Both circuits offer excellent performance. When combined with our RK-series capsules, both will allow your Apex 460 to compete with, if not beat, commercial tube microphones in the $1500-$2500 range.
The Fox 460 has higher output, which means you'll have less preamp noise in your vocal tracks. It benefits from 3 years' worth of refinements and hundreds of customer installations. The V-251 has more headroom, switchable HPF, socketed high-frequency EQ cap, is easier to build, and has a nicer output capacitor, but it costs more, and it needs more preamp gain on quiet sources.
Both these circuits will significantly outperform "capacitor swap" and "tube swap" and "transformer swap" DIY upgrades. Only by designing the entire circuit, top to bottom, can the performance of any microphone be truly optimized.
#4: Cable Upgrade
The XLR7 cable included with the CV-12 is functional but compromised. We offer genuine Gotham GAC-7 cable, imported from Switzerland, hand-terminated in California with Neutrik connectors. The GAC-7 cable has two heavier conductors, which we use for the sensitive tube heater circuit, to minimize losses that would affect the operation of the tube and the sound of the mic.